WorldWideScience

Sample records for satellite mars climate

  1. MEMOS - Mars Environment Monitoring Satellite

    Science.gov (United States)

    Ott, T.; Barabash, S.; von Schéele, F.; Clacey, E.; Pokrupa, N.

    2007-08-01

    The Swedish Institute of Space Physics (IRF) in cooperation with the Swedish Space Corporation (SSC) has conducted first studies on a Mars Environment Monitoring Satellite (MEMOS). The MEMOS microsatellite (mass ELT) Proximity-1 transceiver will autonomously communicate with the parent satellite at inter-satellite ranges 2 kbit/s. The transceiver also implements a coherent transponding mode for orbit determination through two-way Doppler ranging between the parent satellite and MEMOS. In addition ELT is compatible with a future Martian communication and navigation network pursued by NASA, which could be taken advantage of in the future for relaying data or performing ranging via other satellites part of the network. A system design driver for inter-satellite communication at Mars is the high demand of power. This leads to a disk-shape and thus easy to accommodate spacecraft configuration of MEMOS comprising a single sun-pointing solar array favourable in terms of power and spin stability. Multi-junction solar cells, which currently have an efficiency of ~29% under laboratory conditions are a key factor to keep MEMOS solar array area of ~1.15 m2 small compared to the worst case system power requirements of ~105 W. During eclipse periods high-efficient Li-ion batteries (6 x 20 Wh) will ensure power supply. The spacecraft and payload design will incorporate new technology developments such as autonomous navigation, MicroElectroMechanical Systems MEMS, Micro- Opto-ElectroMechanical Systems MOEMS and new materials to achieve low mass at high performance. Thereby it will profit from Swedish developments and heritage in small- / microsatellites like Astrid-2, SMART-1 or the upcoming rendezvous and formation flying demonstration mission PRISMA.

  2. The Climate of Early Mars

    Science.gov (United States)

    Wordsworth, Robin D.

    2016-06-01

    The nature of the early martian climate is one of the major unanswered questions of planetary science. Key challenges remain, but a new wave of orbital and in situ observations and improvements in climate modeling have led to significant advances over the past decade. Multiple lines of geologic evidence now point to an episodically warm surface during the late Noachian and early Hesperian periods 3-4 Ga. The low solar flux received by Mars in its first billion years and inefficiency of plausible greenhouse gases such as CO2 mean that the steady-state early martian climate was likely cold. A denser CO2 atmosphere would have caused adiabatic cooling of the surface and hence migration of water ice to the higher-altitude equatorial and southern regions of the planet. Transient warming caused melting of snow and ice deposits and a temporarily active hydrological cycle, leading to erosion of the valley networks and other fluvial features. Precise details of the warming mechanisms remain unclear, but impacts, volcanism, and orbital forcing all likely played an important role. The lack of evidence for glaciation across much of Mars's ancient terrain suggests the late Noachian surface water inventory was not sufficient to sustain a northern ocean. Though mainly inhospitable on the surface, early Mars may nonetheless have presented significant opportunities for the development of microbial life.

  3. The Climate of Early Mars

    CERN Document Server

    Wordsworth, Robin

    2016-01-01

    The nature of the early Martian climate is one of the major unanswered questions of planetary science. Key challenges remain, but a new wave of orbital and in situ observations and improvements in climate modeling have led to significant advances over the last decade. Multiple lines of geologic evidence now point to an episodically warm surface during the late Noachian and early Hesperian periods 3-4 Ga. The low solar flux received by Mars in its first billion years and inefficiency of plausible greenhouse gases such as CO2 means that the steady-state early Martian climate was likely cold. A denser CO2 atmosphere would have caused adiabatic cooling of the surface and hence migration of water ice to the higher altitude equatorial and southern regions of the planet. Transient warming caused melting of snow and ice deposits and a temporarily active hydrological cycle, leading to erosion of the valley networks and other fluvial features. Precise details of the warming mechanisms remain unclear, but impacts, volca...

  4. The Mars Color Imager (MARCI) on the Mars Climate Orbiter

    Science.gov (United States)

    Malin, M. C.; Calvin, W.; Clancy, R. T.; Haberle, R. M.; James, P. B.; Lee, S. W.; Thomas, P. C.; Caplinger, M. A.

    2001-08-01

    The Mars Color Imager, or MARCI, experiment on the Mars Climate Orbiter (MCO) consists of two cameras with unique optics and identical focal plane assemblies (FPAs), Data Acquisition System (DAS) electronics, and power supplies. Each camera is characterized by small physical size and mass (~6 × 6 × 12 cm, including baffle; case downlink data rate. Under better downlink conditions the WA will provide kilometer-scale global maps of atmospheric phenomena such as clouds, hazes, dust storms, and the polar hood. Limb observations will provide additional detail on atmospheric structure at 13 scale-height resolution. The Medium Angle (MA) camera is designed to study selected areas of Mars at regional scale. From 400 km altitude its 6° FOV, which covers ~40 km at 40 m/pixel, will permit all locations on the planet except the poles to be accessible for image acquisitions every two mapping cycles (roughly 52 sols). Eight spectral channels between 425 and 1000 nm provide the ability to discriminate both atmospheric and surface features on the basis of composition. The primary science objectives of MARCI are to (1) observe Martian atmospheric processes at synoptic scales and mesoscales, (2) study details of the interaction of the atmosphere with the surface at a variety of scales in both space and time, and (3) examine surface features characteristic of the evolution of the Martian climate over time. MARCI will directly address two of the three high-level goals of the Mars Surveyor Program: Climate and Resources. Life, the third goal, will be addressed indirectly through the environmental factors associated with the other two goals.

  5. MarsCAT: Mars Array of ionospheric Research Satellites using the CubeSat Ambipolar Thruster

    Science.gov (United States)

    Bering, E. A., III; Pinsky, L.; Li, L.; Jackson, D. R.; Chen, J.; Reed, H.; Moldwin, M.; Kasper, J. C.; Sheehan, J. P.; Forbes, J.; Heine, T.; Case, A. W.; Stevens, M. L.; Sibeck, D. G.

    2015-12-01

    The MarsCAT (Mars Array of ionospheric Research Satellites using the CubeSat Ambipolar Thruster) Mission is a two 6U CubeSat mission to study the ionosphere of Mars proposed for the NASA SIMPLeX opportunity. The mission will investigate the plasma and magnetic structure of the Martian ionosphere, including transient plasma structures, magnetic field structure and dynamics, and energetic particle activity. The transit plan calls for a piggy back ride with Mars 2020 using a CAT burn for MOI, the first demonstration of CubeSat propulsion for interplanetary travel. MarsCAT will make correlated multipoint studies of the ionosphere and magnetic field of Mars. Specifically, the two spacecraft will make in situ observations of the plasma density, temperature, and convection in the ionosphere of Mars. They will also make total electron content measurements along the line of sight between the two spacecraft and simultaneous 3-axis local magnetic field measurements in two locations. Additionally, MarsCAT will demonstrate the performance of new CubeSat telemetry antennas designed at the University of Houston that are designed to be low profile, rugged, and with a higher gain than conventional monopole (whip) antennas. The two MarsCAT CubeSats will have five science instruments: a 3-axis DC magnetometer, adouble-Langmuir probe, a Faraday cup, a solid state energetic particle detector (Science Enhancement Option), and interspacecraft total electron content radio occulation experiment. The MarsCAT spacecraft will be solar powered and equipped with a CAT thruster that can provide up to 4.8 km/s of delta-V, which is sufficient to achieve Mars orbit using the Mars 2020 piggyback. They have an active attitude control system, using a sun sensor and flight-proven star tracker for determination, and momentum wheels for 3-axis attitude control.

  6. Chaos, storms and climate on Mars

    CERN Document Server

    Kite, Edwin S; Michaels, Timothy; Dietrich, William E; Manga, Michael

    2011-01-01

    Channel networks on the plateau adjacent to Juventae Chasma have the highest drainage densities reported on Mars.We model frozen precipitation on the Juventae plateau,finding that the trigger for forming these channel networks could have been ephemeral lakeshore precipitation,and that they do not require past temperatures higher than today.If short-lived and localized events explain some dendritic channel networks on Mars, this would weaken the link between dendritic valley networks and surface climate conditions that could sustain life. Our analysis uses MRAMS simulations and HiRISE DTMs.We model localized weather systems driven by water vapor release from ephemeral lakes during outflow channel formation.At Juventae Chasma,mean snowfall reaches a maximum of 0.9mm/hr water equivalent on the SW rim of the chasm.Radiative effects of the thick cloud cover raise maximum (minimum, mean) plateau surface temperatures by up to 24K(9K, 17K)locally.The key result is that the area of maximum modeled precipitation shows ...

  7. SATELLITE OBSERVATIONS FOR EDUCATION OF CLIMATE CHANGE

    Directory of Open Access Journals (Sweden)

    ILONA PAJTÓK-TARI

    2011-03-01

    Full Text Available This paper surveys the key statements of the IPCC (2007 Reportbased mainly on the satellite-borne observations to support teaching climatechange and geography by using the potential of this technology. In theIntroduction we briefly specify the potential and the constraints of remote sensing.Next the key climate variables for indicating the changes are surveyed. Snow andsea-ice changes are displayed as examples for these applications. Testing theclimate models is a two-sided task involving satellites, as well. Validation of theability of reconstructing the present climate is the one side of the coin, whereassensitivity of the climate system is another key task, leading to consequences onthe reality of the projected changes. Finally some concluding remarks arecompiled, including a few ideas on the ways how these approaches can be appliedfor education of climate change.

  8. Globally Gridded Satellite observations for climate studies

    Science.gov (United States)

    Knapp, K.R.; Ansari, S.; Bain, C.L.; Bourassa, M.A.; Dickinson, M.J.; Funk, C.; Helms, C.N.; Hennon, C.C.; Holmes, C.D.; Huffman, G.J.; Kossin, J.P.; Lee, H.-T.; Loew, A.; Magnusdottir, G.

    2011-01-01

    Geostationary satellites have provided routine, high temporal resolution Earth observations since the 1970s. Despite the long period of record, use of these data in climate studies has been limited for numerous reasons, among them that no central archive of geostationary data for all international satellites exists, full temporal and spatial resolution data are voluminous, and diverse calibration and navigation formats encumber the uniform processing needed for multisatellite climate studies. The International Satellite Cloud Climatology Project (ISCCP) set the stage for overcoming these issues by archiving a subset of the full-resolution geostationary data at ~10-km resolution at 3-hourly intervals since 1983. Recent efforts at NOAA's National Climatic Data Center to provide convenient access to these data include remapping the data to a standard map projection, recalibrating the data to optimize temporal homogeneity, extending the record of observations back to 1980, and reformatting the data for broad public distribution. The Gridded Satellite (GridSat) dataset includes observations from the visible, infrared window, and infrared water vapor channels. Data are stored in Network Common Data Format (netCDF) using standards that permit a wide variety of tools and libraries to process the data quickly and easily. A novel data layering approach, together with appropriate satellite and file metadata, allows users to access GridSat data at varying levels of complexity based on their needs. The result is a climate data record already in use by the meteorological community. Examples include reanalysis of tropical cyclones, studies of global precipitation, and detection and tracking of the intertropical convergence zone.

  9. Honey Bees, Satellites and Climate Change

    Science.gov (United States)

    Esaias, W.

    2008-05-01

    Life isn't what it used to be for honey bees in Maryland. The latest changes in their world are discussed by NASA scientist Wayne Esaias, a biological oceanographer with NASA Goddard Space Flight Center. At Goddard, Esaias has examined the role of marine productivity in the global carbon cycle using visible satellite sensors. In his personal life, Esaias is a beekeeper. Lately, he has begun melding his interest in bees with his professional expertise in global climate change. Esaias has observed that the period when nectar is available in central Maryland has shifted by one month due to local climate change. He is interested in bringing the power of global satellite observations and models to bear on the important but difficult question of how climate change will impact bees and pollination. Pollination is a complex, ephemeral interaction of animals and plants with ramifications throughout terrestrial ecosystems well beyond the individual species directly involved. Pollinators have been shown to be in decline in many regions, and the nature and degree of further impacts on this key interaction due to climate change are very much open questions. Honey bee colonies are used to quantify the time of occurrence of the major interaction by monitoring their weight change. During the peak period, changes of 5-15 kg/day per colony represent an integrated response covering thousands of hectares. Volunteer observations provide a robust metric for looking at spatial and inter-annual variations due to short term climate events, complementing plant phenology networks and satellite-derived vegetation phenology data. In central Maryland, the nectar flows are advancing by about -0.6 d/y, based on a 15 yr time series and a small regional study. This is comparable to the regional advancement in the spring green-up observed with MODIS and AVHRR. The ability to link satellite vegetation phenology to honey bee forage using hive weight changes provides a basis for applying satellite

  10. Climatic variations on Mars. I - Astronomical theory of insolation

    Science.gov (United States)

    Ward, W. R.

    1974-01-01

    Description of variations in the solar insolation on Mars that result from oscillations of the orbital eccentricity and the obliquity of the planet. Changes in the eccentricity and obliquity are produced by gravitation perturbations from the sun and the other planets, and a detailed account of the time evolution of these quantities is given. Particular attention is paid to the obliquity oscillations, which exert a strong influence on the climate of Mars. Changes in the earth's obliquity are also calculated, and its behavior is contrasted with that of Mars. Although the eccentricity produces important north-south seasonal asymmetries, a change in the obliquity causes a strong latitudinal redistribution of the solar insolation. Especially noteworthy is the fact that the yearly insolation at the poles of Mars varies by over 100% between the extremes of the obliquity range.

  11. Cadence and cause of lake-forming climates on Mars

    Science.gov (United States)

    Kite, Edwin; Goldblatt, Colin; Gao, Peter; Mayer, David; Sneed, Jonathan

    2016-10-01

    Paleolakes on Mars record a sustained hydrologic cycle, but soils upstream record a largely dry past, so lake-forming climates were intermittent. The cadence of lakes on Mars is constrained by relatively young (~3 Ga) deltas and alluvial fans. Deposit build-up required lakes to persist for >2 Kyr (assuming dilute flow), but the watersheds' little-weathered soils indicate a swift return to dry conditions. The lake-forming climates' duty cycle and trigger mechanism remain unknown. Here we show that these data are inconsistent with many previously-proposed triggers for lake-forming climates, but consistent with a novel CH4-burst mechanism. Assuming runoff was sourced from snowmelt, SO2- and impact-triggered warming are too brief, and H2-enabled warming too persistent, to match data. However, chaotic transitions in mean obliquity are a potential trigger with suitable cadence. Mean-obliquity transitions drive latitudinal shifts in temperature and ice loading that destabilize CH4 clathrate. For achievable hydrate stability zone occupancy fractions, CH4 builds up to levels whose direct radiative forcing is comparable to a quadrupling of CO2 (20 W/m2), and sufficient to modulate lake-forming climates. Sub-lake CH4 destabilization provides positive feedback. Photolysis of CH4 curtails individual lake-forming climates to 105-106 yr duration, and depletion of CH4-clathrate limits lake-forming climates to 1-3 in number, consistent with intermittency data. We further propose that Mars' first atmospheric collapse could drive ice sheets from highlands to poles, destabilizing sub-ice clathrate and triggering the formation of the ~4 Ga-old valley networks. Our results show how a warmer early Mars can undergo intermittent orbitally-triggered excursions to a warm, wet climate state.

  12. The present and past climates of planet Mars

    Directory of Open Access Journals (Sweden)

    Forget F.

    2009-02-01

    Full Text Available Mars is a small planet with a thin atmosphere of almost pure carbon dioxide. To first order, the Martian meteorology can be compared with what one would expect on a cold, dry desert-like Earth. However, several phenomena make the Martian climate system more complex than it appears. First, as much as 30% of the carbon dioxide atmosphere condenses every winter at high latitude to form CO2 ice polar caps, inducing large surface pressure variations all over the planet and an atmospheric circulation without equivalent on Earth. Second, a highly variable amount of suspended dust lifted by the winds modifies the radiative properties of the atmosphere, with sometime global dust storms able to totally shroud the planet. Last, a peculiar water cycle occurs on Mars, with water vapor transported by the atmosphere between the polar caps and possibly subsurface reservoirs, allowing the formation of clouds, hazes and frost. Telescopic and spacecraft observations have shown us that this complex climate system is highly variable, seasonally and from year to year, but these variations remain poorly understood. In fact, the Martian climate system has probably experienced large variations related to the oscillations in the parameters of the orbit and rotation of Mars (obliquity a few millions or even thousand of years ago. These oscillations affected surface temperatures and the water cycle, inducing the mobilization and accumulation of large ice deposits in various locations on the planets. In a much distant past, it is also likely that Mars may have been a completely different planet. The observations of the geology (dry riverbeds and deltas, lacustrine sediments and mineralogy (clay, sulfate of the oldest surface on Mars dating back to more than 3 billions years ago provide evidence that liquid water was then abundant on the surface, at least episodically. Mars may have been warmed by a thicker atmosphere containing greenhouse gas and clouds, high geothermal

  13. Satellite-based climate information within the WMO RA VI Regional Climate Centre on Climate Monitoring

    Science.gov (United States)

    Obregón, A.; Nitsche, H.; Körber, M.; Kreis, A.; Bissolli, P.; Friedrich, K.; Rösner, S.

    2014-05-01

    The World Meteorological Organization (WMO) established Regional Climate Centres (RCCs) around the world to create science-based climate information on a regional scale within the Global Framework for Climate Services (GFCS). The paper introduces the satellite component of the WMO Regional Climate Centre on Climate Monitoring (RCC-CM) for Europe and the Middle East. The RCC-CM product portfolio is based on essential climate variables (ECVs) as defined by the Global Climate Observing System (GCOS), spanning the atmospheric (radiation, clouds, water vapour) and terrestrial domains (snow cover, soil moisture). In the first part, the input data sets are briefly described, which are provided by the EUMETSAT (European Organisation for the Exploitation of Meteorological Satellites) Satellite Application Facilities (SAF), in particular CM SAF, and by the ESA (European Space Agency) Climate Change Initiative (CCI). In the second part, the derived RCC-CM products are presented, which are divided into two groups: (i) operational monitoring products (e.g. monthly means and anomalies) based on near-real-time environmental data records (EDRs) and (ii) climate information records (e.g. climatologies, time series, trend maps) based on long-term thematic climate data records (TCDRs) with adequate stability, accuracy and homogeneity. The products are provided as maps, statistical plots and gridded data, which are made available through the RCC-CM website (www.dwd.de/rcc-cm).

  14. Intraseasonal and Interannual Variability of Mars Present Climate

    Science.gov (United States)

    Hollingsworth, Jeffery L.; Bridger, Alison F. C.; Haberle, Robert M.

    1996-01-01

    This is a Final Report for a Joint Research Interchange (JRI) between NASA Ames Research Center and San Jose State University, Department of Meteorology. The focus of this JRI has been to investigate the nature of intraseasonal and interannual variability of Mars'present climate. We have applied a three-dimensional climate model based on the full hydrostatic primitive equations to determine the spatial, but primarily, the temporal structures of the planet's large-scale circulation as it evolves during a given seasonal advance, and, over multi-annual cycles. The particular climate model applies simplified physical parameterizations and is computationally efficient. It could thus easily be integrated in a perpetual season or advancing season configuration, as well as over many Mars years. We have assessed both high and low-frequency components of the circulation (i.e., motions having periods of Omicron(2-10 days) or greater than Omicron(10 days), respectively). Results from this investigation have explored the basic issue whether Mars' climate system is naturally 'chaotic' associated with nonlinear interactions of the large-scale circulation-regardless of any allowance for year-to-year variations in external forcing mechanisms. Titles of papers presented at scientific conferences and a manuscript to be submitted to the scientific literature are provided. An overview of a areas for further investigation is also presented.

  15. Early Mars Climate Modeling and the Faint Young Sun Paradox.

    Science.gov (United States)

    Haberle, Robert M.

    2015-01-01

    Today Mars is a cold, dry, desert planet. Liquid water is not stable on its surface. There are no lakes, seas, or oceans, and precipitation falls as snowfall. Yet early in its history during the Noachian epoch, there is geological and mineralogical evidence that liquid water from rainfall flowed on its surface creating drainage systems, lakes, and - possibly - seas and oceans. More recent observations by Curiosity in Gale crater hint that such conditions may have persited into the Hesperian. The implication is that early Mars had a wamer climate than it does today as a result of a thicker atmosphere with a more powerful greenhouse effect capable of producing an active hydrological cycle with rainfall, runoff, and evaporation. Since Mariner 9 began accumulating such evidence, researchers have been trying to understand what kind of a climate system could have created greenhouse conditions favorable for liquid water. Unfortunately, the problem is not yet solved.

  16. G. Marconi: A Data Relay Satellite for Mars Communications

    Science.gov (United States)

    Dionisio, C.; Marcozzi, M.; Landriani, C.

    2002-01-01

    Mars has always been a source of intrigue and fascination. Recent scientific discoveries have stimulated this longstanding interest, leading to a renaissance in Mars exploration. Future missions to Mars will be capable of long-distance surface mobility, hyperspectral imaging, subsurface exploration, and even life-detection. Manned missions and, eventually, colonies may follow. No mission to the Red Planet stands alone. New scientific and technological knowledge is passed on from one mission to the next, not only improving the journey into space, but also providing benefits here on Earth. The Mars Relay Network, an international constellation of Mars orbiters with relay radios, directly supports other Mars missions by relaying communications between robotic vehicles at Mars and ground stations on Earth. The ability of robotic visitors from Earth to explore Mars will take a gigantic leap forward in 2007 with the launch of the Guglielmo Marconi Orbiter (GMO), the first spacecraft primarily dedicated to providing communication relay, navigation and timing services at Mars. GMO will be the preeminent node of the Mars Relay Network. GMO will relay communications between Earth and robotic vehicles near Mars. GMO will also provide navigation services to spacecraft approaching Mars. GMO will receive transmissions from ground stations on Earth at X-band and will transmit to ground stations on Earth at X- and Ka-bands. GMO will transmit to robotic vehicles at Mars at UHF and receive from these vehicles at UHF and X-band. GMO's baseline 4450 km circular orbit provides complete coverage of the planet for telecommunication and navigation support. GMO will arrive at Mars in mid-2008, just before the NetLander and Mars Scout missions that will be its first users. GMO is designed for a nominal operating lifetime of 10 years and will support nominal commanding and data acquisition, as well as mission critical events such as Mars Orbit Insertion, Entry, Descent and Landing, and Mars

  17. Estimation of micrometeorites and satellite dust flux surrounding Mars in the light of MAVEN results

    Science.gov (United States)

    Pabari, J. P.; Bhalodi, P. J.

    2017-05-01

    Recently, MAVEN observed dust around Mars from ∼150 km to ∼1000 km and it is a puzzling question to the space scientists about the presence of dust at orbital altitudes and about its source. A continuous supply of dust from various sources could cause existence of dust around Mars and it is expected that the dust could mainly be from either the interplanetary source or the Phobos/Deimos. We have studied incident projectiles or micrometeorites at Mars using the existing model, in this article. Comparison of results with the MAVEN results gives a new value of the population index S, which is reported here. The index S has been referred in a power law model used to describe the number of impacting particles on Mars. In addition, the secondary ejecta from natural satellites of Mars can cause a dust ring or torus around Mars and remain present for its lifetime. The dust particles whose paths are altered by the solar wind over its lifetime, could present a second plausible source of dust around Mars. We have investigated escaping particles from natural satellites of Mars and compared with the interplanetary dust flux estimation. It has been found that flux rate at Mars is dominated (∼2 orders of magnitude higher) by interplanetary particles in comparison with the satellite originated dust. It is inferred that the dust at high altitudes of Mars could be interplanetary in nature and our expectation is in agreement with the MAVEN observation. As a corollary, the mass loss from Martian natural satellites is computed based on the surface erosion by incident projectiles.

  18. CONTRIBUTION OF SATELLITE-BORN INFORMATION TO CLIMATE SCIENCE

    Directory of Open Access Journals (Sweden)

    MIKA J.

    2015-03-01

    Full Text Available Observed climate processes play important role in understanding the ongoing changes in the climate system. Our paper intends to present this cross-section of climate science illustrated by selected satellite images and diagrams in four parts. (i. Technical possibilities of the observations are briefly surveyed first. Many satellite platforms and devices started working in the 1980 and 1990s, definitely for climate purposes. (ii. Climate forcing factors and their radiation effects are comprehended, including direct observation of solar irradiance and volcanic aerosol concentration allowing us to compare natural factors to the anthropogenic ones. (iii. Detection of changes in the Earth climate system follows next, including the atmosphere, the oceans and the cryosphere, as well. (iv. Finally, satellite-born results in validation of climate models are presented in three aspects: reconstruction of present climate, validation of simulated changes and investigation of feedback mechanisms driving climate sensitivity to the external forcing factors. The above possibilities of using satellite information in climate science are mostly illustrated by key figures of the IPCC AR5 Report (2013.

  19. The Mars climate for a photovoltaic system operation

    Science.gov (United States)

    Appelbaum, Joseph; Flood, Dennis J.

    1989-01-01

    Detailed information on the climatic conditions on Mars are very desirable for the design of photovoltaic systems for establishing outposts on the Martian surface. The distribution of solar insolation (global, direct and diffuse) and ambient temperature is addressed. This data are given at the Viking lander's locations and can also be used, to a first approximation, for other latitudes. The insolation data is based on measured optical depth of the Martian atmosphere derived from images taken of the sun with a special diode on the Viking cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation. The ambient temperature (diurnal and yearly distribution) is based on direct measurements with a thermocouple at 1.6 m above the ground at the Viking lander locations. The insolation and ambient temperature information are short term data. New information about Mars may be forthcoming in the future from new analysis of previously collected data or from future flight missions. The Mars climate data for photovoltaic system operation will thus be updated accordingly.

  20. Secular Climate Change on Mars: An Update Using One Mars Year of MSL Pressure Data

    Science.gov (United States)

    Haberle, R. M.; Gomez-Elvira, J.; de la Torre Juarez, M.; Harri, A-M.; Hollingsworth, J. L.; Kahanpaa, H.; Kahre, M. A.; Lemmon, M.; Martin-Torres, F. J.; Mischna, M.; Moores, J. E.; Newman, C.; Rafkin, S. C. R.; Renno, N.; Richardson, M. I.; Rodriguez-Manfredi, J. A.; Thomas, P.; Vasavada, A. R.; Wong, M. H.; Zorzano-Mier, M-P.

    2014-01-01

    . Given that there has been no unusual behavior in the climate system as observed by a variety of spacecraft at Mars since Phoenix, its seems more likely that the Phoenix data simply did not have a long enough record to accurately determine annual mean pressure changes as Haberle and Kahre (2010) cautioned. In the absence of a strong signal in the MSL data, we conclude that if the SPRC is loosing mass it is not going into the atmosphere reservoir.

  1. Assessing group dynamics by individual radio satellites in the Mars-500 project

    OpenAIRE

    Johannes, Bernd; Sitev, A. S.; Vinokhodova, A. G.; Salnitski, V.P.; Savchenko, Eduardo; Artyukhova, Anna; Bubeev, Yuri

    2013-01-01

    In a methodological feasibility experiment a wireless group structure (WLGS) monitor system was developed and tested during the Mars500 project. Twice a week each crew member brought a small short-distance radio satellite registering the presence of any other sensor in-room in five second intervals during the wake time. Six satellites were additionally attached to the wall of the simulator’s main compartments. The time being together was registered as well as the signal amplitude providing an...

  2. The Mars Climate Database (MCD version 5.3)

    Science.gov (United States)

    Millour, Ehouarn; Forget, Francois; Spiga, Aymeric; Vals, Margaux; Zakharov, Vladimir; Navarro, Thomas; Montabone, Luca; Lefevre, Franck; Montmessin, Franck; Chaufray, Jean-Yves; Lopez-Valverde, Miguel; Gonzalez-Galindo, Francisco; Lewis, Stephen; Read, Peter; Desjean, Marie-Christine; MCD/GCM Development Team

    2017-04-01

    Our Global Circulation Model (GCM) simulates the atmospheric environment of Mars. It is developped at LMD (Laboratoire de Meteorologie Dynamique, Paris, France) in close collaboration with several teams in Europe (LATMOS, France, University of Oxford, The Open University, the Instituto de Astrofisica de Andalucia), and with the support of ESA (European Space Agency) and CNES (French Space Agency). GCM outputs are compiled to build a Mars Climate Database, a freely available tool useful for the scientific and engineering communities. The Mars Climate Database (MCD) has over the years been distributed to more than 300 teams around the world. The latest series of reference simulations have been compiled in a new version (v5.3) of the MCD, released in the first half of 2017. To summarize, MCD v5.3 provides: - Climatologies over a series of synthetic dust scenarios: standard (climatology) year, cold (ie: low dust), warm (ie: dusty atmosphere) and dust storm, all topped by various cases of Extreme UV solar inputs (low, mean or maximum). These scenarios have been derived from home-made, instrument-derived (TES, THEMIS, MCS, MERs), dust climatology of the last 8 Martian years. The MCD also provides simulation outputs (MY24-31) representative of these actual years. - Mean values and statistics of main meteorological variables (atmospheric temperature, density, pressure and winds), as well as surface pressure and temperature, CO2 ice cover, thermal and solar radiative fluxes, dust column opacity and mixing ratio, [H20] vapor and ice columns, concentrations of many species: [CO], [O2], [O], [N2], [H2], [O3], ... - A high resolution mode which combines high resolution (32 pixel/degree) MOLA topography records and Viking Lander 1 pressure records with raw lower resolution GCM results to yield, within the restriction of the procedure, high resolution values of atmospheric variables. - The possibility to reconstruct realistic conditions by combining the provided climatology with

  3. Geochemistry of Carbonates on Mars: Implications for Climate History and Nature of Aqueous Environments

    OpenAIRE

    Niles, Paul B.; Catling, David C.; Berger, Gilles; Chassefière, Eric; Ehlmann, Bethany L.; Michalski, Joseph R.; Morris, Richard; Ruff, Steven W.; Sutter, Brad

    2013-01-01

    Ongoing research on martian meteorites and a new set of observations of carbonate minerals provided by an unprecedented series of robotic missions to Mars in the past 15 years help define new constraints on the history of martian climate with important crosscutting themes including: the CO_2 budget of Mars, the role of Mg-, Fe-rich fluids on Mars, and the interplay between carbonate formation and acidity. Carbonate minerals have now been identified in a wide range of localities on Mars as...

  4. The ESA climate change initiative: Satellite data records for essential climate variables

    DEFF Research Database (Denmark)

    Hollmann, R.; Merchant, C.J.; Saunders, R.

    2013-01-01

    The European Space Agency (ESA) has launched the Climate Change Initiative (CCI) to provide satellite-based climate data records (CDRs) that meet the challenging requirements of the climate community. The aim is to realize the full potential of the long-term Earth observation (EO) archives...... that both ESA and third parties have established. This includes aspects of producing a CDR, which involve data acquisition, calibration, algorithm development, validation, maintenance, and provision of the data to the climate research community. The CCI is consistent with several international efforts...... targeting the generation of satellite derived climate data records. One focus of the CCI is to provide products for climate modelers who increasingly use satellite data to initialize, constrain, and validate models on a wide range of space and time scales....

  5. A Sustained Greenhouse Climate on Mars following an Impact Event

    Science.gov (United States)

    Segura, T.; Toon, B.; Colaprete, T.; McKay, C.

    2007-12-01

    The existence of craters of size 200 km and greater proves that large (30-250 km diameter) impacts were abundant in the early history of Mars. Injected water from three sources (the impactor, water innate to the crater, and from melting of the polar caps) provide periods of rain following such impacts. Very hot, global debris blankets are another consequence of these large impacts, and these layers create a thermal pulse that propagates into the subsurface, melting additional water. The melted and precipitated water and debris blanket combine to produce a temporarily altered climate. This research shows time-dependent modeled calculations of this altered climate, and focuses in particular on a possible "runaway" greenhouse state that might be initiated as a result of the additional heat and a sufficiently rapid supply of the melted and precipitated water to the atmosphere. Our model is a 1-D radiative-convective model coupled to a 1-D model of the regolith to calculate the evolution of the surface and subsurface temperatures. The effects of latent heating, cloud condensation, precipitation, and evaporation are included in the model. We also show mathematically how the effects of large asteroid or comet impacts can cause a planet to reach the runaway greenhouse state, and illustrate how this solution is part of a bi-stable climate solution for terrestrial planets. One solution is found when a planet cools from high temperature, the other when the planet warms from a cool state. The hot solution represents a planet in the runaway regime, while the cold solution represents a planet with most of its water condensed at the surface. If a planet cools from a large temperature perturbation, caused by a large impact, it is possible that the planet will remain stable in the runaway climate rather than returning to the low temperature climate state.

  6. The South Residual CO 2 Cap on Mars: Investigations with a Mars Global Climate Model

    Science.gov (United States)

    Kahre, Melinda A.; Dequaire, Julie; Hollingsworth, Jeffery L.; Haberle, Robert

    2016-10-01

    The CO2 cycle is one of the three controlling climate cycles on Mars. One aspect of the CO2 cycle that is not yet fully understood is the existence of a residual CO2 ice cap that is offset from the south pole. Previous investigations suggest that the atmosphere could control the placement of the south residual cap (e.g., Colaprete et al., 2005). These investigations show that topographically forced stationary eddies in the south during southern hemisphere winter produce colder atmospheric temperatures and increased CO2 snowfall over the hemisphere where the residual cap resides. Since precipitated CO2 ice produces higher surface albedos than directly deposited CO2 ice, it is plausible that CO2 snowfall resulting from the zonally asymmetric atmospheric circulation produces surface ice albedos high enough to maintain a residual cap only in one hemisphere. Our current work builds on these initial investigations with a version of the NASA Ames Mars Global Climate Model (GCM) that includes a sophisticated CO2 cloud microphysical scheme. Processes of cloud nucleation, growth, sedimentation, and radiative effects are accounted for. Simulated results thus far agree well with the Colaprete et al. study—the zonally asymmetric nature of the atmospheric circulation produces enhanced snowfall over the residual cap hemisphere throughout much of the winter season. However, the predicted snowfall patterns vary significantly with season throughout the cap growth and recession phases. We will present a detailed analysis of the seasonal evolution of the predicted atmospheric circulation and snowfall patterns to more fully evaluate the hypothesis that the atmosphere controls the placement of the south residual cap.

  7. Properties of the moon, Mars, Martian satellites, and near-earth asteroids

    Science.gov (United States)

    Taylor, Jeffrey G.

    1989-01-01

    Environments and surface properties of the moon, Mars, Martian satellites, and near-earth asteroids are discussed. Topics include gravity, atmospheres, surface properties, surface compositions, seismicity, radiation environment, degradation, use of robotics, and environmental impacts. Gravity fields vary from large fractions of the earth's field such as 1/3 on Mars and 1/6 on the moon to smaller fractions of 0.0004 g on an asteroid 1 km in diameter. Spectral data and the analogy with meteor compositions suggest that near-earth asteroids may contain many resources such as water-rich carbonaceous materials and iron-rich metallic bodies. It is concluded that future mining and materials processing operations from extraterrestrial bodies require an investment now in both (1) missions to the moon, Mars, Phobos, Deimos, and near-earth asteroids and (2) earth-based laboratory research in materials and processing.

  8. Mars: A Planet with a Dynamic Climate System

    Science.gov (United States)

    Haberle, Robert M.

    2013-01-01

    Mars is a well-observed planet. Since the 1960s orbiters, landers, rovers, and earth-based telescopic observations show that its climate system is dynamic. Its dynamic nature, largely the result of atmosphere-surface interactions, is most obvious in the seasonal cycles of dust, water, and carbon dioxide that define the planet's climate system. These cycles are linked through the global circulation and MGS, Odyssey, Phoenix, MER, Mars Express, MRO, and now MSL have continuously observed them at Mars for the past 16 years. Their observations show that while the seasonal cycles are largely annually repeatable, there are interannual variations. Planet-encircling dust storms, for example, are quasi-triennial and originate over a broader range of seasons and locations than previously thought. Water moves from pole-to-pole each year in a largely, but not precisely, repeatable pattern that suggests but does not demand non-polar surface reservoirs. And the seasonal CO2 polar caps grow and retreat in a very predictable way with only minor deviations from year-to-year in spite of significant differences in atmospheric dust content. These behaviors suggest a complicated but robust coupled system in which these cycles interact to produce the greatest interannual variability in the dust cycle and least variability in the CO2 cycle. The nature of these interactions is the subject of ongoing research, but clouds, both water ice and CO2 ice, now appear to play a bigger role than believed at the end of the 20th century. There may also be some long-term trends in these cycles as there is evidence from imaging data, for example, that the south polar residual cap may not be stable on decadal to centennial time scales. On even longer time scales, the discovery of as much as 5 mb global equivalent of buried CO2 ice near the south pole, the detection of vast quantities of subsurface water ice at very shallow depths in midlatitudes of both hemispheres, and the presence of remnant glacial

  9. Rapid Climate Change and Implications for Habitability on Mars

    Science.gov (United States)

    Irwin, R. P.

    2012-12-01

    Ongoing work on Martian geomorphology suggests at least three phases of landscape modification: 1) ubiquitous crater degradation and development of intercrater geomorphic surfaces during at least the Middle and Late Noachian Epochs, 2) incision of valley networks around the Noachian/Hesperian transition, and 3) one or more intervals of lesser fluvial erosion in the Late Hesperian or Early Amazonian Epochs. Crater degradation was prolonged, but we do not know whether it was continuous or intermittent over long geologic timescales. It is also unknown whether the Hesperian decline in weathering and crater degradation was abrupt or gradual. Fluvial networks on dated surfaces suggest at least two periods of activity separated by significant time spans. For example, fluvial erosion occurred both before and well after the Gale crater and Holden crater impacts on opposite sides of Mars, and both before and after the development of the crustal dichotomy boundary scarp. Published estimates of discharge, runoff production, denudation, and drainage density are collectively consistent with geologically brief intervals of fluvial erosion. These results suggest that habitable surface environments may have been similarly short-lived, and that adaptation to subsurface environments would have been key to survival of microbial life. Studies of the Martian paleoclimate have tried to reconcile a faint young Sun with compelling evidence for past flowing and ponded water. Attempts to model a global mean temperature above 0°C have been mostly unsuccessful, suggesting either that input parameters are in error or that a different critical condition for fluvial erosion applied. Even assuming a thicker Noachian to Hesperian atmosphere, which would be necessary to support surface water, Mars would maintain cold traps at the poles under most axial obliquity conditions. An active water cycle would depend both on a thicker atmosphere and on liberating ice from the poles, perhaps temporarily

  10. Precise Orbit Determination of Earth's Satellites for Climate Change Investigation

    Science.gov (United States)

    Vespe, Francesco

    The tremendous improvement of the gravity field models which we are achieving with the last Earth's satellite missions like, CHAMP, GRACE and GOCE devoted to its recovery could make feasibile the use of precise orbit determination (POD) of Earth satellites as a tool for sensing global changes of some key atmosphere parameters like refractivity and extinction. Such improvements indeed, coupled with the huge number of running Earth's satellites and combinations of their orbital parameters (namely the nodes) in a gravity field free fashion (hereafter GFF) can magnify the solar radiation pressure acting on medium earth orbit satellites :GPS, Etalon and, in near real future GALILEO and its smooth modulation through the Earth's atmosphere (penumbra). We would remind that The GFF technique is able to cancel out with "n" satellite orbital parameters the first n-1 even zonal harmonics of the gravity field. Previously it was demonstrated that the signal we want to detect could in principle emerge from the noise threshold but, more refined models of the atmosphere would be needed to perform a more subtle analysis. So we will re-compute the signal features of penumbra by applying more refined atmospheric models. The analysis will be performed by including in GFF Earth's satellites equipped with DORIS systems (Jason, Spot 2-3-4-5, ENVISAT etc.) other than those ranged with SLR and GPS. The introduction of DORIS tracked satellites indeed will allow to cancel higher and higher order of even zonal harmonics and will make still more favourable the signal to noise budget. The analysis will be performed over a time span of at least few tens of years just to enhance probable climate signatures.

  11. Satellite Climate Data Records: Development, Applications, and Societal Benefits

    Directory of Open Access Journals (Sweden)

    Wenze Yang

    2016-04-01

    Full Text Available This review paper discusses how to develop, produce, sustain, and serve satellite climate data records (CDRs in the context of transitioning research to operation (R2O. Requirements and critical procedures of producing various CDRs, including Fundamental CDRs (FCDRs, Thematic CDRs (TCDRs, Interim CDRs (ICDRs, and climate information records (CIRs are discussed in detail, including radiance/reflectance and the essential climate variables (ECVs of land, ocean, and atmosphere. Major international CDR initiatives, programs, and projects are summarized. Societal benefits of CDRs in various user sectors, including Agriculture, Forestry, Fisheries, Energy, Heath, Water, Transportation, and Tourism are also briefly discussed. The challenges and opportunities for CDR development, production and service are also addressed. It is essential to maintain credible CDR products by allowing free access to products and keeping the production process transparent by making source code and documentation available with the dataset.

  12. Operational climate monitoring from space: the EUMETSAT satellite application facility on climate monitoring (CM-SAF

    Directory of Open Access Journals (Sweden)

    J. Schulz

    2008-05-01

    Full Text Available The Satellite Application Facility on Climate Monitoring (CM-SAF aims at the provision of satellite-derived geophysical parameter data sets suitable for climate monitoring. CM-SAF provides climatologies for Essential Climate Variables (ECV, as required by the Global Climate Observing System implementation plan in support of the UNFCCC. Several cloud parameters, surface albedo, radiation fluxes at the top of the atmosphere and at the surface as well as atmospheric temperature and humidity products form a sound basis for climate monitoring of the atmosphere. The products are categorized in monitoring data sets obtained in near real time and data sets based on carefully intercalibrated radiances. The CM-SAF products are derived from several instruments on-board operational satellites in geostationary and polar orbit, i.e., the Meteosat and NOAA satellites, respectively. The existing data sets will be continued using data from the instruments on-board the new EUMETSAT Meteorological Operational satellite (MetOP. The products have mostly been validated against several ground-based data sets both in situ and remotely sensed. The accomplished accuracy for products derived in near real time is sufficient to monitor variability on diurnal and seasonal scales. Products based on intercalibrated radiance data can also be used for climate variability analysis up to inter-annual scale. A central goal of the recently started Continuous Development and Operations Phase of the CM-SAF (2007–2012 is to further improve all CM-SAF data sets to a quality level that allows for studies of inter-annual variability.

  13. Monitoring Surface Climate With its Emissivity Derived From Satellite Measurements

    Science.gov (United States)

    Zhou, Daniel K.; Larar, Allen M.; Liu, Xu

    2012-01-01

    Satellite thermal infrared (IR) spectral emissivity data have been shown to be significant for atmospheric research and monitoring the Earth fs environment. Long-term and large-scale observations needed for global monitoring and research can be supplied by satellite-based remote sensing. Presented here is the global surface IR emissivity data retrieved from the last 5 years of Infrared Atmospheric Sounding Interferometer (IASI) measurements observed from the MetOp-A satellite. Monthly mean surface properties (i.e., skin temperature T(sub s) and emissivity spectra epsilon(sub v) with a spatial resolution of 0.5x0.5-degrees latitude-longitude are produced to monitor seasonal and inter-annual variations. We demonstrate that surface epsilon(sub v) and T(sub s) retrieved with IASI measurements can be used to assist in monitoring surface weather and surface climate change. Surface epsilon(sub v) together with T(sub s) from current and future operational satellites can be utilized as a means of long-term and large-scale monitoring of Earth 's surface weather environment and associated changes.

  14. Scientific Goals and Objectives for the Human Exploration of Mars: 1. Biology and Atmosphere/Climate

    Science.gov (United States)

    Levine, Joel S.; Garvin, J. B.; Anbar, A. D.; Beaty, D. W.; Bell, M. S.; Clancy, R. T.; Cockell, C. S.; Connerney, J. E.; Doran, P. T.; Delory, G.; Dickson, J. T.; Elphic, R. C.; Eppler, D. B.; Fernandez-Remolar, D. C.; Head, J. W.; Helper, M.; Gruener, J. E.; Heldmann, J.; Hipkin, V.; Lane, M. D.; Levy, J.; Moersch, J.; Ori, G. G.; Peach, L.; Poulet, F.

    2008-01-01

    To prepare for the exploration of Mars by humans, as outlined in the new national vision for Space Exploration (VSE), the Mars Exploration Program Analysis Group (MEPAG), chartered by NASA's Mars Exploration Program (MEP), formed a Human Exploration of Mars Science Analysis Group (HEM-SAG), in March 2007. HEM-SAG was chartered to develop the scientific goals and objectives for the human exploration of Mars based on the Mars Scientific Goals, Objectives, Investigations, and Priorities.1 The HEM-SAG is one of several humans to Mars scientific, engineering and mission architecture studies chartered in 2007 to support NASA s plans for the human exploration of Mars. The HEM-SAG is composed of about 30 Mars scientists representing the disciplines of Mars biology, climate/atmosphere, geology and geophysics from the U.S., Canada, England, France, Italy and Spain. MEPAG selected Drs. James B. Garvin (NASA Goddard Space Flight Center) and Joel S. Levine (NASA Langley Research Center) to serve as HEMSAG co-chairs. The HEM-SAG team conducted 20 telecons and convened three face-to-face meetings from March through October 2007. The management of MEP and MEPAG were briefed on the HEM-SAG interim findings in May. The HEM-SAG final report was presented on-line to the full MEPAG membership and was presented at the MEPAG meeting on February 20-21, 2008. This presentation will outline the HEM-SAG biology and climate/atmosphere goals and objectives. A companion paper will outline the HEM-SAG geology and geophysics goals and objectives.

  15. Arctic Climate Variability and Trends from Satellite Observations

    Directory of Open Access Journals (Sweden)

    Xuanji Wang

    2012-01-01

    Full Text Available Arctic climate has been changing rapidly since the 1980s. This work shows distinctly different patterns of change in winter, spring, and summer for cloud fraction and surface temperature. Satellite observations over 1982–2004 have shown that the Arctic has warmed up and become cloudier in spring and summer, but cooled down and become less cloudy in winter. The annual mean surface temperature has increased at a rate of 0.34°C per decade. The decadal rates of cloud fraction trends are −3.4%, 2.3%, and 0.5% in winter, spring, and summer, respectively. Correspondingly, annually averaged surface albedo has decreased at a decadal rate of −3.2%. On the annual average, the trend of cloud forcing at the surface is −2.11 W/m2 per decade, indicating a damping effect on the surface warming by clouds. The decreasing sea ice albedo and surface warming tend to modulate cloud radiative cooling effect in spring and summer. Arctic sea ice has also declined substantially with decadal rates of −8%, −5%, and −15% in sea ice extent, thickness, and volume, respectively. Significant correlations between surface temperature anomalies and climate indices, especially the Arctic Oscillation (AO index, exist over some areas, implying linkages between global climate change and Arctic climate change.

  16. Evidence for climate change in the satellite cloud record

    Science.gov (United States)

    Norris, Joel R.; Allen, Robert J.; Evan, Amato T.; Zelinka, Mark D.; O'Dell, Christopher W.; Klein, Stephen A.

    2016-08-01

    Clouds substantially affect Earth’s energy budget by reflecting solar radiation back to space and by restricting emission of thermal radiation to space. They are perhaps the largest uncertainty in our understanding of climate change, owing to disagreement among climate models and observational datasets over what cloud changes have occurred during recent decades and will occur in response to global warming. This is because observational systems originally designed for monitoring weather have lacked sufficient stability to detect cloud changes reliably over decades unless they have been corrected to remove artefacts. Here we show that several independent, empirically corrected satellite records exhibit large-scale patterns of cloud change between the 1980s and the 2000s that are similar to those produced by model simulations of climate with recent historical external radiative forcing. Observed and simulated cloud change patterns are consistent with poleward retreat of mid-latitude storm tracks, expansion of subtropical dry zones, and increasing height of the highest cloud tops at all latitudes. The primary drivers of these cloud changes appear to be increasing greenhouse gas concentrations and a recovery from volcanic radiative cooling. These results indicate that the cloud changes most consistently predicted by global climate models are currently occurring in nature.

  17. Investigating Satellite Microwave observations of Precipitation in Different Climate Regimes

    Science.gov (United States)

    Wang, N.; Ferraro, R. R.

    2013-12-01

    Microwave satellite remote sensing of precipitation over land is a challenging problem due to the highly variable land surface emissivity, which, if not properly accounted for, can be much greater than the precipitation signal itself, especially in light rain/snow conditions. Additionally, surfaces such as arid land, deserts and snow cover have brightness temperature characteristics similar to precipitation Ongoing work by GPM microwave radiometer team is constructing databases through a variety of means, however, there is much uncertainty as to what is the optimal information needed for the wide array of sensors in the GPM constellation, including examination of regional conditions. The original data sets will focus on stratification by emissivity class, surface temperature and total perceptible water. We'll perform sensitivity studies to determine the potential role of ancillary data (e.g., land surface temperature, snow cover/water equivalent, etc.) to improve precipitation estimation over land in different climate regimes, including rain and snow. In other words, what information outside of the radiances can help describe the background and subsequent departures from it that are active precipitating regions? It is likely that this information will be a function of the various precipitation regimes. Statistical methods such as Principal Component Analysis (PCA) will be utilized in this task. Databases from a variety of sources are being constructed. They include existing satellite microwave measurements of precipitating and non-precipitating conditions, ground radar precipitation rate estimates, surface emissivity climatology from satellites, surface temperature and TPW from NWP reanalysis. Results from the analysis of these databases with respect to the microwave precipitation sensitivity to the variety of environmental conditions in different climate regimes will be discussed.

  18. Inferring Early Mars Climate from Comparison of Drainage Basins' Morphologies on Mars and Earth

    Science.gov (United States)

    Stepinski, T. F.; Stepinski, A. P.

    2005-03-01

    A similarity map constructed for 94 Martian and terrestrial drainage basins reveals a systematic difference between the two planets. This difference is explained by climatic differences with Martian basins developing in extremely dry climate.

  19. Towards a satellite-based sea ice climate data record

    Science.gov (United States)

    Meier, W. N.; Fetterer, F.; Stroeve, J.; Cavalieri, D.; Parkinson, C.; Comiso, J.; Weaver, R.

    2005-12-01

    Sea ice plays an important role in the Earth's climate through its influence on the surface albedo, heat and moisture transfer between the ocean and the atmosphere, and the thermohaline circulation. Satellite data reveal that since 1979, summer Arctic sea ice has, overall, been declining at a rate of almost 8%/decade, with recent summers (beginning in 2002) being particularly low. The receding sea ice is having an effect on wildlife and indigenous peoples in the Arctic, and concern exists that these effects may become increasingly severe. Thus, a long-term, ongoing climate data record of sea ice is crucial for tracking the changes in sea ice and for assessing the significance of long-term trends. Since the advent of passive microwave satellite instruments in the early 1970s, sea ice has been one of the most consistently monitored climate parameters. There is now a 27+ year record of sea ice extent and concentration from multi-channel passive microwave radiometers that has undergone inter-sensor calibration and other quality controls to ensure consistency throughout the record. Several algorithms have been developed over the years to retrieve sea ice extent and concentration and two of the most commonly used algorithms, the NASA Team and Bootstrap, have been applied to the entire SMMR-SSM/I record to obtain a consistent time series. These algorithms were developed at NASA Goddard Space Flight Center and are archived at the National Snow and Ice Data Center. However, the complex surface properties of sea ice affect the microwave signature, and algorithms can yield ambiguous results; no single algorithm has been found to work uniformly well under all sea ice conditions. Thus there are ongoing efforts to further refine the algorithms and the time series. One approach is to develop data fusion methods to optimally combine sea ice fields from two or more algorithms. Another approach is to take advantage of the improved capabilities of JAXA's AMSR-E sensor on NASA's Aqua

  20. Climate Cycling on Early Mars Caused by the Carbonate-Silicate Cycle

    CERN Document Server

    Batalha, Natasha E; Haqq-Misra, Jacob; Kasting, James F

    2016-01-01

    For decades, scientists have tried to explain the evidence for fluvial activity on early Mars, but a consensus has yet to emerge regarding the mechanism for producing it. One hypothesis suggests early Mars was warmed by a thick greenhouse atmosphere. Another suggests that early Mars was generally cold but was warmed occasionally by impacts or by episodes of enhanced volcanism. These latter hypotheses struggle to produce the amounts of rainfall needed to form the martian valleys, but are consistent with inferred low rates of weathering compared to Earth. Here, we provide a geophysical mechanism that could have induced cycles of glaciation and deglaciation on early Mars. Our model produces dramatic climate cycles with extended periods of glaciation punctuated by warm periods lasting up to 10 Myr, much longer than those generated in other episodic warming models. The cycles occur because stellar insolation was low, and because CO2 outgassing is not able to keep pace with CO2 consumption by silicate weathering fo...

  1. Reconstructing regional climate networks from irregularly sampled satellite data

    Science.gov (United States)

    Wiedermann, Marc; Donner, Reik V.; Sykioti, Olga; Papadimitriou, Constantinos; Kurths, Jürgen

    2015-04-01

    With the increasing availability of remote sensing data Earth System Analysis has taken a great step forward. Satellite data with high resolution in time and space allow for an in-depth analysis of small-scale processes in the climate as well as ecosystems. This data type, however, also harbors crucial conceptual complications. First, depending on whether the satellite is orbiting on an ascending or descending path systematic biases are induced into the dataset and both measurements can not be evaluated simultaneously without an appropriate preprocessing. Second, remote sensing data are usually not produced with equidistant temporal sampling, but might contain huge gaps, due to cloud cover or maintenance work and irregular time steps, due to the orbiting time of the satellite. In this work, we utilize sea surface temperature (SST) data obtained from the SMOS satellite as part of ESA's Earth Explorer Mission to study small-scale regional interactions between different parts of the Mediterranean, Aegean and Black Sea. In a first step, we create homogeneous time series for each grid point by combining data from ascending and descending satellite paths by utilizing principal component and singular spectrum analysis. To address the issue of irregular temporal sampling we utilize a kernel weighted version of the linear cross-correlation function to compute lagged correlations between all pairs of grid points in the dataset. By setting a threshold to the thus obtained correlation matrix we obtain a binary matrix which can be interpreted as the adjacency matrix of a complex network. We then use tools from complex network theory to study regional interdependencies in the study area for different time lags of up to forty days. We find that the obtained networks represent well the observed average wind directions and speeds and display interaction structures between small regions in the Aegean Sea, which are in good agreement with earlier observations. The methods presented

  2. Delta and fan morphologies on Mars as climate indicators (Utrecht Studies in Geosciences 042)

    NARCIS (Netherlands)

    de Villiers, G.

    2013-01-01

    The presence, duration and quantity of water on Mars remains an important research topic in planetary science. Large valley networks, regional outflow channels, and small-scale gullies indicate the presence of water on the surface at certain points in the past. However, the climatic history and evol

  3. Delta and fan morphologies on Mars as climate indicators (Utrecht Studies in Geosciences 042)

    NARCIS (Netherlands)

    de Villiers, G.

    2013-01-01

    The presence, duration and quantity of water on Mars remains an important research topic in planetary science. Large valley networks, regional outflow channels, and small-scale gullies indicate the presence of water on the surface at certain points in the past. However, the climatic history and evol

  4. Mars

    CERN Document Server

    Elkins-Tanton, Linda T

    2010-01-01

    Mars exploration has never been more active, and our understanding of the planet is advancing rapidly. New discoveries reveal gullies carved by recent groundwater flow, thick ice deposits protected by rocks and soil even at the equator, and new evidence for lakes and seas in Mars' past. The Martian surface has some of the oldest planetary crust in the solar system, containing clues to conditions in early planets that cannot be obtained elsewhere.Beginning with a discussion of Mars as a planet in orbit, Mars, Revised Edition covers fundamental facts about this planet, including its mass and siz

  5. Morphology of drainage basins as an indicator of climate on early Mars

    Science.gov (United States)

    Stepinski, T. F.; Stepinski, A. P.

    2005-12-01

    We show that drainage basin morphology correlates with climate. Computational analysis of the 46 basins extracted from the western slopes of the Andes reveals the existence of four different basin morphologic classes. This purely geomorphic partition correlates with division of the same basins on the grounds of climate types. Basins are compared using circularity functions as their formal representations. Self-organizing maps and dendrograms are employed to provide basin classification. One class of basin morphologies corresponds to sites in the arid Atacama Desert, and the other class corresponds to sites in the Atacama exhibiting groundwater sapping landforms. Using the same technique, we study a larger sample of 94 basins that, in addition to the Andean basins, includes other terrestrial basins and 26 basins from Martian sites that show prominent valley networks. The classification of this larger set shows that morphologies of Martian and terrestrial basins bifurcate at the root of the dendrogram, forming two separate domains of basin morphologies. The similarity map reveals that, of all the terrestrial basins, the Atacama Desert basins are morphologically closest to the Martian basins. Extrapolating the terrestrial morphology-climate linkage to Mars points to formation of valley networks in a hyperarid climatic environment. We submit that the Atacama Desert provides the best possible terrestrial morphologic analog to valley network sites on Mars. We discuss climatic and hydrologic particularities of the Atacama Desert and hypothesize that a similar environment existed on early Mars.

  6. Satellite image analysis for surveillance, vegetation and climate change

    Energy Technology Data Exchange (ETDEWEB)

    Cai, D Michael [Los Alamos National Laboratory

    2011-01-18

    Recently, many studies have provided abundant evidence to show the trend of tree mortality is increasing in many regions, and the cause of tree mortality is associated with drought, insect outbreak, or fire. Unfortunately, there is no current capability available to monitor vegetation changes, and correlate and predict tree mortality with CO{sub 2} change, and climate change on the global scale. Different survey platforms (methods) have been used for forest management. Typical ground-based forest surveys measure tree stem diameter, species, and alive or dead. The measurements are low-tech and time consuming, but the sample sizes are large, running into millions of trees, covering large areas, and spanning many years. These field surveys provide powerful ground validation for other survey methods such as photo survey, helicopter GPS survey, and aerial overview survey. The satellite imagery has much larger coverage. It is easier to tile the different images together, and more important, the spatial resolution has been improved such that close to or even higher than aerial survey platforms. Today, the remote sensing satellite data have reached sub-meter spatial resolution for panchromatic channels (IKONOS 2: 1 m; Quickbird-2: 0.61 m; Worldview-2: 0.5 m) and meter spatial resolution for multi-spectral channels (IKONOS 2: 4 meter; Quickbird-2: 2.44 m; Worldview-2: 2 m). Therefore, high resolution satellite imagery can allow foresters to discern individual trees. This vital information should allow us to quantify physiological states of trees, e.g. healthy or dead, shape and size of tree crowns, as well as species and functional compositions of trees. This is a powerful data resource, however, due to the vast amount of the data collected daily, it is impossible for human analysts to review the imagery in detail to identify the vital biodiversity information. Thus, in this talk, we will discuss the opportunities and challenges to use high resolution satellite imagery and

  7. Geology and insolation-driven climatic history of Amazonian north polar materials on Mars.

    Science.gov (United States)

    Tanaka, Kenneth L

    2005-10-13

    Mariner 9 and Viking spacecraft images revealed that the polar regions of Mars, like those of Earth, record the planet's climate history. However, fundamental uncertainties regarding the materials, features, ages and processes constituting the geologic record remained. Recently acquired Mars Orbiter Laser Altimeter data and Mars Orbiter Camera high-resolution images from the Mars Global Surveyor spacecraft and moderately high-resolution Thermal Emission Imaging System visible images from the Mars Odyssey spacecraft permit more comprehensive geologic and climatic analyses. Here I map and show the history of geologic materials and features in the north polar region that span the Amazonian period (approximately 3.0 Gyr ago to present). Erosion and redeposition of putative circumpolar mud volcano deposits (formed by eruption of liquefied, fine-grained material) led to the formation of an Early Amazonian polar plateau consisting of dark layered materials. Crater ejecta superposed on pedestals indicate that a thin mantle was present during most of the Amazonian, suggesting generally higher obliquity and insolation conditions at the poles than at present. Brighter polar layered deposits rest unconformably on the dark layers and formed mainly during lower obliquity over the past 4-5 Myr (ref. 20). Finally, the uppermost layers post-date the latest downtrend in obliquity <20,000 years ago.

  8. Mars

    CERN Document Server

    Day, Trevor

    2006-01-01

    Discusses the fundamental facts concerning this mysterious planet, including its mass, size, and atmosphere, as well as the various missions that helped planetary scientists document the geological history of Mars. This volume also describes Mars'' seasons with their surface effects on the planet and how they have changed over time.

  9. Total cloud cover from satellite observations and climate models

    Directory of Open Access Journals (Sweden)

    P. Probst

    2010-09-01

    Full Text Available Global and zonal monthly means of cloud cover fraction for total cloudiness (CF from the ISCCP D2 dataset are compared to same quantity produced by the 20th century simulations of 21 climate models from the World Climate Research Programme's (WCRP's Coupled Model Intercomparison Project phase 3 (CMIP3 multi-model dataset archived by the Program for Climate Model Diagnosis and Intercomparison (PCMDI. The comparison spans the time frame from January 1984 to December 1999 and the global and zonal average of CF are studied. The restriction to total cloudiness depends on the output of some models that does not include the 3D cloud structure. It is shown that the global mean of CF for the PCMDI/CMIP3 models, averaged over the whole period, exhibits a considerable variance and generally underestimates the ISCCP value. Very large discrepancies among models, and between models and observations, are found in the polar areas, where both models and satellite observations are less reliable, and especially near Antarctica. For this reason the zonal analysis is focused over the 60° S–60° N latitudinal belt, which includes the tropical area and mid latitudes. The two hemispheres are analyzed separately to show the variation of the amplitude of the seasonal cycle. Most models overestimate the yearly averaged values of CF over all of the analysed areas, while differences emerge in their ability to capture the amplitude of the seasonal cycle. The models represent, in a qualitatively correct way, the magnitude and the weak sign of the seasonal cycle over the whole geographical domain, but overestimate the strength of the signal in the tropical areas and at mid-latitudes, when taken separately. The interannual variability of the two yearly averages and of the amplitude of the seasonal cycle is greatly underestimated by all models in each area analysed. This work shows that the climate models have an heterogeneous behaviour in simulating the CF over

  10. Mars

    CERN Document Server

    Payment, Simone

    2017-01-01

    This curriculum-based, fun, and approachable book offers everything young readers need to know to begin their study of the Red Planet. They will learn about the fundamental aspects of the Mars, including its size, mass, surface features, interior, orbit, and spin. Further, they will learn about the history of the missions to Mars, including the Viking spacecraft and the Curiosity and MAVEN rovers. Finally, readers will learn about why scientists think there's a chance that Mars is or was suitable for life. With stunning imagery from NASA itself, readers will have a front seat-view of the missi

  11. Evidence for Pervasive Cold Climates Throughout Most of Mars History

    Science.gov (United States)

    Christensen, P. R.

    2004-05-01

    Evidence from a variety of sources suggests that Mars has a significant water inventory. However, it appears that this inventory has been frozen throughout much of Mars history. Infrared spectral mapping by the TES and THEMIS orbital instruments has shown that the martian surface is dominated by unweathered volcanic rocks, including olivine-rich basalts in numerous areas. THEMIS 100-m scale multispectral imaging reveals compositional variations at these scales. However these compositional differences are due to differences in the composition of igneous materials. Regions of high (~20 percent) olivine abundance basalts have been mapped at the scales of individual flows and rock layers, including exposures at multiple layers with the Valles Marineris system, demonstrating that large regions of Mars have not experienced significant surface or sub-surface water at any time in their history. THEMIS has not detected mineralogical evidence for carbonate rock layers at 100-m scales, despite the discovery by the MGS TES of minor carbonate in the martian dust. The existing carbonates can be produced by surface-atmosphere interactions, without requiring the presence and erosion of a carbonate rock source. THEMIS imaging has, however, shown evidence for extensive ice deposits in the mid- to high-latitude regions, some of which show evidence for recent downslope flow. These mantles preferentially occur on pole-facing slopes in mid-latitudes and are interpreted to be remnants of once-extensive snows deposited during recent periods of high obliquity. Melting of these deposits during intervening warmer periods may form the young gullies that are also observed at these latitudes. A pervasive surface mantle found from 30 to 50o in both hemispheres has been interpreted by Mustard et al. (2001) to result from ice-cemented soils that have formed recently and are currently being devolatilized. The poleward transition from a dissected to continuous surface on this mantle corresponds to a

  12. Climate Cycling on Early Mars Caused by the Carbonate-Silicate Cycle

    Science.gov (United States)

    Kasting, J. F.; Batalha, N. E.; Haqq-Misra, J. D.; Kopparapu, R.

    2016-12-01

    For decades, scientists have tried to explain the evidence for fluvial activity on early Mars, but a consensus has yet to emerge regarding the mechanism for producing it. One hypothesis suggests early Mars was warmed by a thick greenhouse atmosphere [1]. Another suggests early Mars was generally cold but was warmed occasionally by impacts or by episodes of enhanced volcanism [2,3], with warming possibly extended by cirrus clouds [4]. These latter hypotheses struggle to produce the amounts of rainfall needed to form the martian valleys, but are consistent with inferred low rates of weathering compared to Earth. We suggest that both schools of thought are partly correct. Mars experienced dramatic climate cycles with extended periods of glaciation punctuated by warm periods lasting up to 10 Myr [5]. Cycles of repeated glaciation and deglaciation occurred because stellar insolation was low, and because CO2 outgassing could not keep pace with CO2 consumption by silicate weathering followed by deposition of carbonates. In order to deglaciate early Mars, substantial outgassing of molecular hydrogen from Mars' reduced crust and mantle was also required, as our own climate model is unable to do this without adding some greenhouse warming from H2 [6,7]. Our hypothesis can be tested by future Mars exploration that better establishes the time scale for valley formation. References: [1] Pollack JB, Kasting JF, Richardson SM, Poliakoff K. 1987. Icarus 71: 203-24 [2] Halevy I, Head JW. 2014. Nature Geoscience 7: 865-8 [3] Segura TL, Toon OB, Colaprete A, Zahnle K. 2002. Science 298: 1977-80 [4] Urata RA, Toon OB. 2013. Icarus 226: 229-50 [5] Batalha NE, Kopparapu RK, Haqq-Misra JD, Kasting JF. submitted. Climate cycling on early Mars caused by the carbonate-silicate cycle. EPSL [6] Ramirez RM, Kopparapu R, Zugger ME, Robinson TD, Freedman R, Kasting JF. 2014. Nature Geosci 7: 59-63 [7] Batalha N, Domagal-Goldman SD, Ramirez R, Kasting JF. 2015. Icarus 258: 337-49

  13. Cryolitozone of Mars- as the climatic indicator of the Martian relict ocean

    Science.gov (United States)

    Ozorovich, Y.; Fournier-Sicre, A.; Linkin, V.; Kosov, A.; Skulachev, D.; Gorbatov, S.; Ivanov, A.; Heggy, E.

    2015-10-01

    The existance of a large Martian cryolitozone consisting of different cryogenic formations both on the surface- polar caps ice and in subsurface layer (and probably overcooled salt solutions in lower horizons) is conditioned mostly by the planet's geological history and atmosphere evolution. The very structure of the cryolitozone with its strongly pronounced zone character owing to drying up of 0 to 200 m thick surface layer in the equatorial latitudes ranging from + 30 to - 300 was formed in the course of long-periodic climatic variations and at present is distincly heterogeneous both depthward and in latitudinal and longtudinal dimensions. The dryed up region of Martian frozen rocks is estimated to have been developing during more than 3.5 bln years, so the upper layer boundary of permafrost can serve as a sort of indicator reflecting the course of Martian climatic evolution. Since the emount of surface moisture and its distribition character are conditioned by the cryolitozone scale structure its investigation is considered to be an important aspect of the forthcoming Martian projects. In order to create Martian climate and atmosphere circulation models the whole complex information on surface provided by optical and infrared ranges observations, regional albedo surface measurements, ground layer thermal flow investigations, etc. must be carefully studed. The investigation of permafrost formation global distribution and their appearance in h ≤1 m thick subsurface layer may be provided successfully by using active-passive microwave remote sensing techniques [1]. Along with optical and infrared observations the method of orbital panoramic microwave radiometry in centi- and decimeter ranges would contribute to the mapping of the cryolitozone global surface distribution. This proposal discusses methodical and experimental possibilities of this global observation of Martian cryolitozone as the additional way for investigation subsurface of Mars. The main idea of

  14. Global warming and climate forcing by recent albedo changes on Mars

    Science.gov (United States)

    Fenton, L.K.; Geissler, P.E.; Haberle, R.M.

    2007-01-01

    For hundreds of years, scientists have tracked the changing appearance of Mars, first by hand drawings and later by photographs. Because of this historical record, many classical albedo patterns have long been known to shift in appearance over time. Decadal variations of the martian surface albedo are generally attributed to removal and deposition of small amounts of relatively bright dust on the surface. Large swaths of the surface (up to 56 million km2) have been observed to darken or brighten by 10 per cent or more. It is unknown, however, how these albedo changes affect wind circulation, dust transport and the feedback between these processes and the martian climate. Here we present predictions from a Mars general circulation model, indicating that the observed interannual albedo alterations strongly influence the martian environment. Results indicate enhanced wind stress in recently darkened areas and decreased wind stress in brightened areas, producing a positive feedback system in which the albedo changes strengthen the winds that generate the changes. The simulations also predict a net annual global warming of surface air temperatures by ???0.65 K, enhancing dust lifting by increasing the likelihood of dust devil generation. The increase in global dust lifting by both wind stress and dust devils may affect the mechanisms that trigger large dust storm initiation, a poorly understood phenomenon, unique to Mars. In addition, predicted increases in summertime air temperatures at high southern latitudes would contribute to the rapid and steady scarp retreat that has been observed in the south polar residual ice for the past four Mars years. Our results suggest that documented albedo changes affect recent climate change and large-scale weather patterns on Mars, and thus albedo variations are a necessary component of future atmospheric and climate studies. ??2007 Nature Publishing Group.

  15. Global warming and climate forcing by recent albedo changes on Mars.

    Science.gov (United States)

    Fenton, Lori K; Geissler, Paul E; Haberle, Robert M

    2007-04-05

    For hundreds of years, scientists have tracked the changing appearance of Mars, first by hand drawings and later by photographs. Because of this historical record, many classical albedo patterns have long been known to shift in appearance over time. Decadal variations of the martian surface albedo are generally attributed to removal and deposition of small amounts of relatively bright dust on the surface. Large swaths of the surface (up to 56 million km2) have been observed to darken or brighten by 10 per cent or more. It is unknown, however, how these albedo changes affect wind circulation, dust transport and the feedback between these processes and the martian climate. Here we present predictions from a Mars general circulation model, indicating that the observed interannual albedo alterations strongly influence the martian environment. Results indicate enhanced wind stress in recently darkened areas and decreased wind stress in brightened areas, producing a positive feedback system in which the albedo changes strengthen the winds that generate the changes. The simulations also predict a net annual global warming of surface air temperatures by approximately 0.65 K, enhancing dust lifting by increasing the likelihood of dust devil generation. The increase in global dust lifting by both wind stress and dust devils may affect the mechanisms that trigger large dust storm initiation, a poorly understood phenomenon, unique to Mars. In addition, predicted increases in summertime air temperatures at high southern latitudes would contribute to the rapid and steady scarp retreat that has been observed in the south polar residual ice for the past four Mars years. Our results suggest that documented albedo changes affect recent climate change and large-scale weather patterns on Mars, and thus albedo variations are a necessary component of future atmospheric and climate studies.

  16. Evidences of Wet Climate on Early Mars from Analysis of HRSC Observations

    Science.gov (United States)

    Jaumann, Ralf; Tirschj, Daniela; Adeli, Solmaz

    2017-04-01

    Both Geomorphological and mineralogical evidence point to the episodic availability of liquid water on the surface of early Mars. However, the distribution of water was not uniform over space and time. Considerable environmental and climate variations due to latitudinal or elevation effects combined with a diverse surface geology caused distinctively different of local conditions that influenced the planet`s water content. The history of water on Mars has been constantly revised and refined during the past years. Landforms such as widespread valley networks, fluvial deposits and associated assemblages of hydrated clay minerals support the hypothesis that the Martian climate was to some extend warm and wet during the early history of Mars [e.g.,1,2]. At the boundary between the Late Noachian and the Early Hesperian, environmental and climate conditions changed significantly and resulted in a transition towards a colder and dryer climate. The intensity of aqueous activity decreased throughout the Hesperian, including a transition from long-term and repeated precipitation-induced fluvial activity towards reduced, short-term, spatially isolated and groundwater-dominated fluvial erosion [e.g.,3,4,5,6]. At the end of the Hesperian, fluvial erosion has mostly ceased and volcanic, aeolian and glacial processes are interpreted to be dominant on Mars. The Early Amazonian was characterized most likely by a cold and dry climate that was similar to the conditions on recent Mars. However, Mars' climate and aqueous history, in particular the timing of the termination of fluvial activity and the transition from precipitation-induced toward groundwater-dominated erosion as well as the temperature with time, is still subject to debate. Modeling of flow transport processes revealed that the formation of deltas on Mars geologically requires only brief timespans [7] and, based on discharge estimates, the formation of erosional valleys also needs less than a few million years and seems

  17. Towards climate reconstruction on Mars using landscape analysis: Insights from terrestrial analogues

    Science.gov (United States)

    Hauber, E.; Ulrich, M.; Reiss, D.; Hiesinger, H.; Balme, M. R.; Gallagher, C. J.

    2011-12-01

    Many very young landforms on Mars resemble terrestrial glacial and periglacial surface features in permafrost regions and show a latitude-dependent geographic distribution. They include surface mantling, viscous flow features, polygonally fractured ground, patterned ground, fractured mounds, and gullies. Collectively, these landforms are hypothesized to represent the geomorphological surface record of Martian ice ages that were triggered by astronomical forcing and associated climate changes. Many previous studies of possible cold-climate features on Mars considered just one of them in isolation, e.g., polygons or fractured mounds. Such approaches do not consider the geomorphologic context of the landforms, and thus interpretations can be ambiguous due to the possible effect of equifinality. A more comprehensive investigation of the full assemblage of associated landforms (landscape analysis) has the potential to reduce this ambiguity. We use the permafrost landscape of Spitsbergen (Svalbard, Norway) as an analogue for the assemblage of cold-climate landforms that is typically found in mid-latitudes on Mars. Although relatively warm and wet as compared to other cold-climate analogues on Earth, Spitsbergen is a particularly instructive morphological analogue to Mars as it offers many surface features in a close spatial context that are strikingly similar to those on Mars. Based on this comparison, which uses remote sensing and field data from Svalbard, we identify similarities as well as differences, both of which are important in the use of analogues as a means to establish testable hypotheses. We then propose possible scenarios which may help to understand the evolution of Martian landforms into their present state. Of particular interest with respect to the habitability of Martian permafrost is whether liquid water was involved or not. Most phenomena on Mars, but not Svalbard, can plausibly be explained by "dry" permafrost scenarios without the need to invoke

  18. Climate Model Diagnostic and Evaluation: With a Focus on Satellite Observations

    Science.gov (United States)

    Waliser, Duane

    2011-01-01

    Each year, we host a summer school that brings together the next generation of climate scientists - about 30 graduate students and postdocs from around the world - to engage with premier climate scientists from the Jet Propulsion Laboratory and elsewhere. Our yearly summer school focuses on topics on the leading edge of climate science research. Our inaugural summer school, held in 2011, was on the topic of "Using Satellite Observations to Advance Climate Models," and enabled students to explore how satellite observations can be used to evaluate and improve climate models. Speakers included climate experts from both NASA and the National Oceanic and Atmospheric Administration (NOAA), who provided updates on climate model diagnostics and evaluation and remote sensing of the planet. Details of the next summer school will be posted here in due course.

  19. 3D Global Climate Modelling of the environmental effect of meteoritic impacts on Early Mars

    Science.gov (United States)

    Turbet, Martin; Forget, Francois; Gillmann, Cedric; Karatekin, Ozgur; Svetsov, Vladimir; Popova, Olga; Wallemacq, Quentin

    2016-10-01

    There are now robust evidences that liquid water flowed on ancient Mars: dry river beds and lakes, hydrated sedimentary minerals and high erosion rates. Climate models that consider only CO2/H2O as greenhouse gases have been unable yet to produce warm climates suitable for liquid water on Early Mars, given the lower solar luminosity at that time. It has been suggested that the warm conditions required to explain the formation of the 3.8 Gyrs old valley networks could have been transient and produced in response to the meteoritic impacts that occured during the contemporaneous Late Heavy Bombardment (LHB). This scenario is appealing because, in a predominately cold climate, the ice tends to accumulate preferentially in the regions where the rivers were sculpted ('Icy Highlands' scenario). This would be a very efficient mechanism of recharge of the valley network water sources between two impact-induced melting events.Using the LMD Global Climate Model (LMD-GCM) designed for flexible (from cold & dry to warm & wet) conditions, we explored the environmental effect of LHB impact events of various sizes on Early Mars. Our main result is that, whatever the initial impact-induced temperatures and water vapor content injected, warm climates cannot be stable and are in fact short-lived (lifetime of ~ 5 martian years/bar of H2O injected). Moreover, we will give preliminar estimates of the amount of rainfall/snowmelt that can be produced after impact events depending on their size, following three different approaches:1) For large impact events (Dimpactor energy conservation.2) For moderate-size events (5km geothermal heat fluxes using the StagYY Mantle Convection Model. These are used as input in the LMD-GCM to estimate the effiency of basal melting.

  20. Quasi-periodic climate changes on Mars - A review

    Science.gov (United States)

    Pollack, J. B.; Toon, O. B.

    1982-01-01

    The current understanding of the manner in which astronomical variations modulate the Martian climate and thereby lead to the occurrence of laminated polar terrain is considered. The seasonal cycles of dust, carbon dioxide and water, and their responses to astronomical variations, are studied. After an assessment of the way in which these cycles presently operate, for which pertinent spacecraft and ground-based observations are extant, attempts to predict how these cycles may differ under conditions of high and low obliquity and eccentricity are discussed. Attention is given not only to those areas in which there is broad agreement, but also to the controversial and speculative. Key questions include the proportion of dust and water ice in the laminae and its variations within individual layers, the relative importance of older laminae and lower-latitude material as sources of new laminae, and the factors responsible for the youth of the laminated terrain.

  1. What Are the Origins of Detached Layers of Dust on Mars ? Investigation with Global Climate Model

    Science.gov (United States)

    Bertrand, T.; Spiga, A.; Forget, F.

    2014-12-01

    The climate on Mars is strongly controlled by the amount of dust lifted and transported in the atmosphere, which causes fluctuations of air opacity and affects temperatures and winds. Recently, observations of the vertical dust distribution of the Martian atmosphere by the Mars Climate Sounder on board the Mars Reconnaissance Orbiter revealed a phenomenon which is still poorly understood: the formation of detached layers of dust. These detached layers, also confirmed by the Thermal Emission Spectrometer on-board the Mars Global Surveyor, reside above the planetary boundary layer typically at altitudes between 20 and 40 km and have been mostly observed at low latitudes. These detached layers of dust are not reproduced by Global Climate Models (GCM) and different atmospheric processes are discussed and can be combined to explain their origin, such as small-scale lifting, upslope topographic winds, scavenging by water ice clouds, dust storms… Here we use the Martian GCM developed at the Laboratoire de Météorologie Dynamique (LMD) to simulate the formation of detached layers of dust. To start, we developed a new implementation of the water cycle, taking into account nucleation on dust particles, ice particle growth, and scavenging of dust particles due to the condensation of ice. However, this method didn't yield to satisfying results in the GCM. Then, we performed the parameterization in the GCM of the so-called "rocket dust storms", governed by deep convection and able to inject dust at high altitudes in the Martian troposphere. By coupling this new parameterization with general circulation of the GCM, we succeed to model detached layers of dust. Here we present this parameterization and we discuss about the spatial and temporal variability of the detached layers of dust, in comparison with observations.

  2. Mars: History of Climate Change and Evolution of the Water Cycle (Runcorn-Florensky Medal Lecture)

    Science.gov (United States)

    Head, James W.

    2010-05-01

    Atmospheric general circulation models are becoming more and more sophisticated and can now be analyzed at various scales, and include variations in atmospheric water vapor content, orbital parameters and surface properties. A wide variety of geological evidence indicates that the climate on Mars has changed during its past history. We are now approaching the time when synergism is developing between studies of the observed geological record and predictions and results of climate models. Geological evidence for climate change ranges in physical scale from layering in the polar caps and sediments, to meters-thick ice-rich layers extending from high to mid-latitudes, to kilometers-thick polar and circumpolar deposits. Clear temporal changes in the mineralogy and alteration style of surface and subsurface materials signal long-term climate change. Evidence is found throughout the geologic record of Mars, ranging from interpreted Amazonian tropical mountain glaciers to much longer term trends implied by the temporal distribution of geological features such as valley networks and outflow channels. Furthermore, there is strong evidence for changes in the hydrological cycle of Mars that reflect long-term climate change. For the last ~80% of its history (the Hesperian and Amazonian) Mars appears to have been a very cold, hyper-arid polar desert, similar to the McMurdo Dry Valleys of Antarctica. During this time, the hydrologic system on Mars has been horizontally layered, with the near-surface hydrologic cycle involving water movement between the atmosphere, polar caps, the surface and regolith at various latitudes; variations in spin-axis orbital parameters caused significant surface redistribution of ice and dust, and abundant ice has been sequestered beneath glacial debris-cover in the mid-latitudes for several hundred million years. Existing groundwater is sequestered below a globally continuous cryosphere; liquid water occasionally emerged to the surface during

  3. Post-impact climate conditions on early Mars: preliminary results from GCM simulations

    Science.gov (United States)

    Steakley, Kathryn; Murphy, Jim; Kahre, Melinda A.; Haberle, Robert

    2016-10-01

    Observations imply that liquid water was stable on Mars' surface during the late Noachian/early Hesperian era, with valley networks forming roughly 3.5-3.75 billion years ago, possibly from precipitation and runoff (Fassett & Head 2008, Icarus 195, 61; Hynek et al., 2010, JGR Planets, 115, E09008). Climate models, however, struggle to reproduce such warm conditions (Forget et al., 2013, Icarus 21, 81). Volcanism and impacts have been suggested as mechanisms of either inducing a warm and wet environment or causing local melting in a cold and wet environment. Comets and asteroids are capable of injecting into the atmosphere both kinetic energy from the impact and water from the object itself and from vaporized surface and subsurface ice. Segura et al. (2008, JGR Planets 113, E11007) find using a 1-D atmospheric model that significant rainfall and periods of above-freezing temperatures lasting months to years can follow impacts of objects between 30 and 100 km in diameter. We revisit this work utilizing a 3-D global climate model (GCM) to consider the effects of dynamics, topography, global surface ice variations, etc. We present preliminary results from the NASA ARC Mars GCM investigating global temperature and precipitation behavior in a post-impact, early Mars environment.

  4. Clay Mineralogy and Crystallinity as a Climatic Indicator: Evidence for Both Cold and Temperate Conditions on Early Mars

    Science.gov (United States)

    Horgan, B.; Rutledge, A.; Rampe, E. B.

    2015-01-01

    Surface weathering on Earth is driven by precipitation (rain/snow melt). Here we summarize the influence of climate on minerals produced during surface weathering, based on terrestrial literature and our new laboratory analyses of weathering products from glacial analog sites. By comparison to minerals identified in likely surface environments on Mars, we evaluate the implications for early martian climate.

  5. Analysis of high altitude clouds in the martian atmosphere based on Mars Climate Sounder observations

    Science.gov (United States)

    Puspitarini, L.; Määttänen, A.; Fouchet, T.; Kleinboehl, A.; Kass, D. M.; Schofield, J. T.

    2016-11-01

    High altitude clouds have been observed in the Martian atmosphere. However, their properties still remain to be characterized. Mars Climate Sounder (MCS) aboard Mars Reconnaissance Orbiter (MRO) is an instrument that measures radiances in the thermal infrared, both in limb and nadir views. It allows us to retrieve vertical profiles of radiance, temperature and aerosols. Using the MCS data and radiative transfer model coupled with an automated inversion routine, we can investigate the chemical composition of the high altitude clouds. We will present the first results on the properties of the clouds. CO2 ice is the best candidate to be the main component of some high altitude clouds due to the most similar spectral variation compared to water ice or dust, in agreement with previous studies. Using cloud composition of contaminated CO2 ice (dust core surrounded by CO2 ice) might improve the fitting result, but further study is needed.

  6. Semi-automated operation of Mars Climate Simulation chamber - MCSC modelled for biological experiments

    Science.gov (United States)

    Tarasashvili, M. V.; Sabashvili, Sh. A.; Tsereteli, S. L.; Aleksidze, N. D.; Dalakishvili, O.

    2017-10-01

    The Mars Climate Simulation Chamber (MCSC) (GEO PAT 12 522/01) is designed for the investigation of the possible past and present habitability of Mars, as well as for the solution of practical tasks necessary for the colonization and Terraformation of the Planet. There are specific tasks such as the experimental investigation of the biological parameters that allow many terrestrial organisms to adapt to the imitated Martian conditions: chemistry of the ground, atmosphere, temperature, radiation, etc. MCSC is set for the simulation of the conduction of various biological experiments, as well as the selection of extremophile microorganisms for the possible Settlement, Ecopoesis and/or Terraformation purposes and investigation of their physiological functions. For long-term purposes, it is possible to cultivate genetically modified organisms (e.g., plants) adapted to the Martian conditions for future Martian agriculture to sustain human Mars missions and permanent settlements. The size of the chamber allows preliminary testing of the functionality of space-station mini-models and personal protection devices such as space-suits, covering and building materials and other structures. The reliability of the experimental biotechnological materials can also be tested over a period of years. Complex and thorough research has been performed to acquire the most appropriate technical tools for the accurate engineering of the MCSC and precious programmed simulation of Martian environmental conditions. This paper describes the construction and technical details of the equipment of the MCSC, which allows its semi-automated, long-term operation.

  7. A Cloud Greenhouse Effect on Mars: Significant Climate Change in the Recent Past

    Science.gov (United States)

    Haberle, Robert M.; Kahre, Melinda A.; Schaeffer, James R.; Montmessin, Frank; Phillips, R J.

    2012-01-01

    The large variations in Mars orbit parameters are known to be significant drivers of climate change on the Red planet. The recent discovery of buried CO2 ice at the South Pole adds another dimension to climate change studies. In this paper we present results from the Ames GCM that show within the past million years it is possible that clouds from a greatly intensified Martian hydrological cycle may have produced a greenhouse effect strong enough to raise global mean surface temperatures by several tens of degrees Kelvin. It is made possible by the ability of the Martian atmosphere to transport water to high altitudes where cold clouds form, reduce the outgoing longwave radiation, and drive up surface temperatures to maintain global energy balance.

  8. What Can the Curiosity Rover Tell Us About the Climate of Mars?

    Science.gov (United States)

    Haberle, Robert M.

    2013-01-01

    What Can the Curiosity Rover Tell Us About the Climate of Mars? Assessing the habitability of Gale Crater is the goal of the Curiosity Rover, which has been gathering data since landing on the Red Planet last August. To meet that goal, Curiosity brought with it a suite of instruments to measure the biological potential of the landing site, the geology and chemistry of its surface, and local environmental conditions. Some of these instruments illuminate the nature of the planet fs atmosphere and climate system, both for present day conditions as well as for conditions that existed billions of years ago. For present day conditions, Curiosity has a standard meteorology package that measures pressure, temperature, winds and humidity, plus a sensor the measures the UV flux. These data confirm what we learned from previous missions namely that today Mars is a cold, dry, and barren desert-like planet. For past conditions, however, wetter and probably warmer conditions are indicated. Curiosities cameras reveal gravel beds that must have formed by flowing rivers, and sedimentary deposits of layered sand and mudstones possibly associated with lakes. An ancient aqueous environment is further supported by the presence of sulfate veins coursing through some of the rocks in Yellowknife Bay where Curiosity is planning its first drilling activity. I will discuss these results and their implications in this lecture.

  9. A Sustained Greenhouse Climate and Erosion Period on Mars Following an Impact Event

    Science.gov (United States)

    Segura, T.; Toon, O. B.; Colaprete, T.

    2008-12-01

    The existence of craters of size 200 km and greater proves that large (> 30 km diameter) impacts were abundant in the early history of Mars. Injected water from three sources (the impactor, water innate to the crater, and from melting of the polar caps) provides periods of rain following such impacts. Very hot, global debris blankets are another consequence of these large impacts, and these layers create a thermal pulse that propagates into the subsurface, melting additional water. The melted and precipitated water and debris blanket combine to produce a temporarily altered climate. The effects of moderate-sized (30-100 km diameter) impacts on Mars were studied using a 1-dimensional radiative-convective model. The model computes the evolution of temperature following an impact and includes: a subsurface model to compute the evolution of the ground temperature; a hydrological cycle to follow the evaporation, condensation and precipitation of injected and surface evaporated water; a radiative transfer code to compute greenhouse warming by CO2, water vapor, and water clouds; and an atmospheric thermodynamics module to compute the latent heating due to cloud formation/dissipation. We have found that parts of the Martian regolith may be kept above freezing for 95 days to decades by the modeled events. However if we include the radiative effects of water clouds, a sustained greenhouse climate is computed for impactors 50 km in size that could be centuries-long. The amount of water precipitated out of the atmosphere from vaporization of impactor, target, and polar caps, yields global rainfall totals ranging from 40 cm to 18 m depending on the size of the impactor and assumed background CO2 atmosphere. We also estimate the surface erosion following precipitation events and find that the total erosion done by all impactors in time is the same order of magnitude as the total erosion estimated [Golombek and Bridges, 2000] to have occurred on Early Mars.

  10. TROPOMI: Solar backscatter satellite instrument for air quality and climate

    NARCIS (Netherlands)

    Vries, J.de; Laan, E.C.; Hoogeveen, R.W.M.; Jongma, R.T.; Aben, U.; Visser, H.; Boslooper, E.C.; Saari, H.; Dobber, M.; Veefkind, P.; Kleipool, Q.; Levelt, P.F.

    2007-01-01

    TROPOMI is a nadir-viewing grating-based imaging spectrograph in the line of OMI and SCIAMACHY. TROPOMI is part of the ESA Candidate Core Explorer Mission proposal TRAQ and also of the CAMEO satellite proposed for the US NRC decadal study. A TROPOMI-like instrument is part of the ESA/EU Sentinel 4&5

  11. Atmospheric profiling via satellite to satellite occultations near water and ozone absorption lines for weather and climate

    Science.gov (United States)

    Kursinski, E. R.; Ward, D.; Otarola, A. C.; McGhee, J.; Stovern, M.; Sammler, K.; Reed, H.; Erickson, D.; McCormick, C.; Griggs, E.

    2016-05-01

    Significantly reducing weather and climate prediction uncertainty requires global observations with substantially higher information content than present observations provide. While GPS occultations have provided a major advance, GPS observations of the atmosphere are limited by wavelengths chosen specifically to minimize interaction with the atmosphere. Significantly more information can be obtained via satellite to satellite occultations made at wavelengths chosen specifically to characterize the atmosphere. Here we describe such a system that will probe cm- and mmwavelength water vapor absorption lines called the Active Temperature, Ozone and Moisture Microwave Spectrometer (ATOMMS). Profiling both the speed and absorption of light enables ATOMMS to profile temperature, pressure and humidity simultaneously, which GPS occultations cannot do, as well as profile clouds and turbulence. We summarize the ATOMMS concept and its theoretical performance. We describe field measurements made with a prototype ATOMMS instrument and several important capabilities demonstrated with those ground based measurements including retrieving temporal variations in path-averaged water vapor to 1%, in clear, cloudy and rainy conditions, up to optical depths of 17, remotely sensing turbulence and determining rain rates. We conclude with a vision of a future ATOMMS low Earth orbiting satellite constellation designed to take advantage of synergies between observational needs for weather and climate, ATOMMS unprecedented orbital remote sensing capabilities and recent cubesat technological innovations that enable a constellation of dozens of very small spacecraft to achieve many critical, but as yet unfulfilled, monitoring and forecasting needs.

  12. Satellite-based assessment of climate controls on US burned area

    OpenAIRE

    D. C. Morton; G. J. Collatz; Wang, D.; Randerson, J. T.; Giglio, L.; Chen, Y.

    2013-01-01

    Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate–fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burne...

  13. Reconstructing the recent climate of Mars: What can we learn from periglacial terrestrial analogues?

    Science.gov (United States)

    Hauber, E.; Ulrich, M.; Reiss, D.; Hiesinger, H.; Johnsson, A.; Balme, M.; Gallagher, C.

    2012-04-01

    Many very young landforms on Mars resemble terrestrial glacial and periglacial surface features in permafrost regions and show a latitude-dependent geographic distribution. They include surface mantling, viscous flow features, polygonally fractured ground, patterned ground, fractured mounds, and gullies. Collectively, these landforms are hypothesized to represent the geomorphological surface record of Martian ice ages that were triggered by astronomical forcing and associated climate changes. We use the permafrost landscape of Spitsbergen (Svalbard, Norway) as an analogue to the assemblage of cold-climate landforms that is typically found in mid-latitudes on Mars. Although relatively warm and wet as compared to other cold-climate analogues on Earth, Spitsbergen is a particularly instructive morphological analogue to Mars as it offers many surface features in a close spatial context that are strikingly similar to those on Mars. Based on this comparison, which uses remote sensing and field data from Svalbard, we identify similarities as well as differences, both of which are important in the use of analogues as a means to establish testable hypotheses. We then propose possible scenarios which may help to understand the evolution of Martian landforms into their present state. Of particular interest with respect to the habitability of Martian permafrost is whether liquid water was involved or not. Most phenomena on Mars, but not Svalbard, can plausibly be explained by "dry" permafrost scenarios without the need to invoke freeze/thaw. Examples of such processes are the slow creep of ice-debris mixtures in permafrost, such as debris-covered glaciers, ice-cored moraines, rock glaciers or protalus ramparts. Dry scenarios can also be consistent with a significant role of snow or firn. The reduced gravity on the Martian surface implies that significantly thicker snowpacks are required to transform firn into glacier ice, hence thick perennial snowpacks and related nivation

  14. A pathway to generating Climate Data Records of sea-surface temperature from satellite measurements

    Science.gov (United States)

    Minnett, Peter J.; Corlett, Gary K.

    2012-11-01

    In addition to having known uncertainty characteristics, Climate Data Records (CDRs) of geophysical variables derived from satellite measurements must be of sufficient length to resolve signals that might reveal the signatures of climate change against a background of larger, unrelated variability. The length of the record requires using satellite measurements from many instruments over several decades, and the uncertainty requirement implies that a consistent approach be used to establish the errors in the satellite retrievals over the entire period. Retrieving sea-surface temperature (SST) from satellite is a relatively mature topic, and the uncertainties of satellite retrievals are determined by comparison with collocated independent measurements. To avoid the complicating effects of near-surface temperature gradients in the upper ocean, the best validating measurements are from ship-board radiometers that measure, at source, the surface emission that is measured in space, after modification by its propagation through the atmosphere. To attain sufficient accuracy, such ship-based radiometers must use internal blackbody calibration targets, but to determine the uncertainties in these radiometric measurements, i.e. to confirm that the internal calibration is effective, it is necessary to conduct verification of the field calibration using independent blackbodies with accurately known emissivity and at very accurately measured temperatures. This is a well-justifiable approach to providing the necessary underpinning of a Climate Data Record of SST.

  15. Regional climate network analysis from irregularly sampled satellite data

    Science.gov (United States)

    Wiedermann, Marc; Sykioti, Olga; Papadimitriou, Constantinos; Balasis, George; Kurths, Jürgen; Donner, Reik V.

    2016-04-01

    With the increasing availability of remote sensing data Earth System Analysis has taken a great step forward. This type of data, however, also harbors a variety of conceptual complications. First, depending on whether the satellite is orbiting on an ascending or descending path systematic biases are induced into the data, and both measurements cannot be evaluated simultaneously without an appropriate preprocessing. Second, remote sensing data are usually not produced with equidistant temporal sampling, but might contain huge gaps and irregular time steps. Third, the time period covered by the data is often too short to perform an appropriate seasonal detrending. Here, we propose a general framework to create homogeneous anomalized time series for a (multivariate) satellite data set by combining time series from ascending and descending satellite paths or even different missions using principal component and singular spectrum analysis. We then exemplarily apply our method to sea surface temperature data obtained from the SMOS satellite mission to study small-scale regional correlative patterns covering different parts of the Aegean Sea. To address the issue of irregular temporal sampling we utilize a kernel weighted version of the linear cross-correlation function to compute lagged correlations between all pairs of grid points in the data set. By binarizing the thus obtained matrices, we obtain a network representation of the system's similarity structure. Ultimately, we use tools from complex network theory to study regional interdependencies in the study area for different time lags of up to forty days. We find that the obtained networks represent well the observed average wind directions and speeds and display interaction structures between small regions in the Aegean Sea, which are in good agreement with earlier observations. In a second step, we extend the study area to the whole Mediterranean and Black Sea and investigate lagged interactions between these two

  16. Estimating Greenland ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR

    NARCIS (Netherlands)

    Fettweis, X.; Franco, B.; Tedesco, M.; van Angelen, J.H.; Lenaerts, J.T.M.; van den Broeke, M.R.; Gallee, H

    2012-01-01

    We report future projections of Surface Mass Balance (SMB) over the Greenland ice sheet (GrIS) obtained with the regional climate model MAR, forced by the outputs of three CMIP5 General Circulation Models (GCMs) when considering two different warming scenarios (RCP 4.5 and RCP 8.5). The GCMs selecte

  17. Formation of Valley Networks in a Cold and Icy Early Mars Climate: Predictions for Erosion Rates and Channel Morphology

    Science.gov (United States)

    Cassanelli, J. P.; Head, J. W.

    2017-10-01

    Climate models suggest early Mars was cold and icy. To test this prediction we assess the influence of cold conditions and the presence of an ice-cemented substrate on the formation of the valley networks and compare results to morphometric data.

  18. Cloud cover diurnal cycles in satellite data and regional climate model simulations

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifroth, Uwe; Ahrens, Bodo [Frankfurt Univ., Frankfurt am Main (Germany). Inst. for Atmospheric and Environmental Sciences; Hollmann, Rainer [Deutscher Wetterdienst, Offenbach (Germany)

    2012-12-15

    The amount and diurnal cycle of cloud cover play an important role in the energy and water cycle of the earth-atmosphere system and influence the radiation budget of the earth. Due to its importance and the challenging nature of its quantification, cloud cover is considered the biggest uncertainty factor in climate modeling. There is a clear need for reliable cloud datasets suitable for climate model evaluation studies. This study analyzes two datasets of cloud cover and its diurnal cycle derived from satellite observations by the International Satellite Cloud Climatology Project (ISCCP) and by EUMETSAT's Satellite Application Facility on Climate Monitoring (CM SAF) in Africa and Europe. Two regions, Europe and the subtropical southern Atlantic Ocean, were identified as offering distinct cloud cover diurnal cycles reasonably observed by both satellite datasets. In these regions, simulations by the regional climate model COSMO-CLM (CCLM) were evaluated in terms of cloud cover and its diurnal cycle during the time period of 1990 to 2007. Results show that the satellite derived cloud diurnal cycles largely agree, while discrepancies occur under extreme conditions like in the Sahara region. The CCLM is able to simulate the diurnal cycle observed consistently in the two satellite datasets in the South-Atlantic ocean, but not in Europe. CCLM misses the afternoon maximum cloud cover in Summer in Europe, which implies deficiencies in the parameterization of convection and in the treatment of surface-atmosphere interactions. The simulation of the diurnal cycle of the more stratiform cloud cover over the subtropical Atlantic was satisfactory in CCLM. (orig.)

  19. MIRI: Comparison of Mars Express MARSIS ionospheric data with a global climate model

    Science.gov (United States)

    Gonzalez-Galindo, Francisco; Forget, Francois; Gurnett, Donald; Lopez-Valverde, Miguel; Morgan, David D.; Nemec, Frantisek; Chaufray, Jean-Yves; Diéval, Catherine

    2016-07-01

    Observations and computational models are the two fundamental stones of our current knowledge of the Martian atmosphere, and both are expected to contribute to the MIRI effort. Data-model comparisons are thus necessary to identify possible bias in the models and to complement the information provided by the observations. Here we present the comparison of the ionosphere determined from Mars Express MARSIS AIS observations with that simulated by a ground-to-exosphere Global Climate Model for Mars, the LMD-MGCM. We focus the comparison on the density and altitude of the main ionospheric peak. In general, the observed latitudinal and solar zenith angle variability of these parameters is well reproduced by the model, although the model tends to slightly underestimate both the electron density and altitude of the peak. The model predicts also a latitudinal variability of the peak electron density that is not observed. We will discuss the different factors affecting the predicted ionosphere, and emphasize the importance of a good knowledge of the electronic temperature in producing a correct representation of the ionosphere by the model.

  20. Satellite Earth observation data to identify climate and anthropogenic pressures on Bucharest periurban forests

    Energy Technology Data Exchange (ETDEWEB)

    Zoran, Maria; Savastru, Roxana; Savastru, Dan [National Institute of R& D for Optoelectronics, MG5 Bucharest-Magurele, 077125 Romania (Romania); Dida, Adrian [University Transylvania of Brasov, Brasov (Romania)

    2016-03-25

    Satellite Earth observation data in the visible and near-infrared (VNIR) wavelengths represent a useful source of information for forest systems monitoring through derived biogeophysical parameters (vegetation index, leaf area index, canopy cover, fraction of absorbed photosynthetically active radiation, chlorophyll content, net primary production, canopy water stress, etc.). Use of satellite remote sensing data to assess forest spatio-temporal changes due to climatic or anthropogenic stressors is an excellent example of the value of multispectral and multitemporal observations. Fusion technique was applied to time-series multispectral and multitemporal satellite imagery (NOAA AVHRR, MODIS Terra/Aqua, Landsat ETM and IKONOS satellite data) for periurban forest areas Cernica-Branesti, placed in the neighboring of Bucharest town, Romania, over 2002-2014 period.

  1. The Radiative Impact of Water Ice Clouds from a Reanalysis of Mars Climate Sounder Data

    Science.gov (United States)

    Steele, L.; Lewis, S.; Patel, M.

    2014-12-01

    We use a data assimilation scheme coupled to a global climate model (GCM) to investigate the radiative impact of water ice clouds in the atmosphere of Mars. Temperature profiles from Mars Climate Sounder (MCS) are assimilated directly into the GCM. The water ice opacity profiles are used to build a four-dimensional time-space map of water ice clouds, which is then used by the GCM to produce the radiative forcing associated with clouds. This procedure allows clouds to be inserted into the model at the correct time and location, producing the most realistic state from which to analyse cloud radiative effects. The resulting data set allows a detailed study of the atmospheric state that is not possible using observations or models alone. The results show that tropical clouds have a greater impact on the local atmosphere than polar hood clouds, increasing diurnally-averaged temperatures at the 10 Pa level by around 10-15 K. The small radiative impact of the polar hood clouds may be caused by limitations of the MCS retrieval algorithm, meaning optically thick near-surface clouds are not retrieved. Tropical clouds also strengthen the meridional overturning circulation, leading to increased temperatures in the polar warmings by around 6-8 K, and increased temperatures in the tropics by around 2 K due to increased dust loading. The positions and wind speeds of the tropical and high-latitude jets are also modified through changes to the meridional temperature gradients. Work is ongoing to couple the assimilation of ice opacities to a model including an active water cycle.

  2. Mapping the northern plains of Mars: origins, evolution and response to climate change

    Science.gov (United States)

    Balme, Matthew; Conway, Susan; Costard, François; Gallagher, Colman; van Gasselt, Stephan; Hauber, Ernst; Johnsson, Andreas; Kereszturi, Akos; Platz, Thomas; Ramsdale, Jason; Reiss, Dennis; Séjourné, Antoine; Skinner, James; Swirad, Zuzanna

    2014-05-01

    An ISSI (International Space Science Institute) international team has been convened to study the Northern Plain of Mars. The northern plains are extensive, geologically young, low-lying areas that contrast in age and relief to Mars' older, heavily cratered, southern highlands. Mars' northern plains are characterised by a wealth of landforms and landscapes that have been inferred to be related to the presence of ice or ice-rich material near, beneath, or at the surface. Such landforms include 'scalloped' pits and depressions, polygonally-patterned grounds, and viscous flow features similar in form to terrestrial glacial or ice-sheet landforms. Furthermore, new (within the last few years) impact craters have exposed ice in the northern plains, and spectral data from orbiting instruments have revealed the presence of tens of percent by weight of water within the upper most ~50 cm of the martian surface at high latitudes. The northern plains comprise three linked zones: Acidalia Planitia, Utopia Planitia and Arcadia Planitia. Each region consists of a shallow basin, with the three areas are separated by low topographic divides. Our aim is to study the ice-related geomorphology of each region in order to understand the origins, evolution and response to climate change of ice on Mars. In particular, by comparing and contrasting the three separate basins we hope to determine if the processes that created the ice-related terrains are regional (perhaps basin limited) or global in scope, and whether the differing geology of each basin has an effect on the ice-related features observed there. The ISSI team is using planetary geomorphological mapping to meet this aim. Three long strips, each about 250 km wide and spanning the ~30N to ~80N latitude range have been defined and sub-teams are each mapping a single area. The group contains experts in mapping, GIS and crater counting (details in the size-frequency distribution of impact craters on a planetary surface can reveal

  3. Climatology and first-order composition estimates of mesospheric clouds from Mars Climate Sounder limb spectra

    Science.gov (United States)

    Sefton-Nash, E.; Teanby, N. A.; Montabone, L.; Irwin, P. G. J.; Hurley, J.; Calcutt, S. B.

    2013-01-01

    Mesospheric clouds have been previously observed on Mars in a variety of datasets. However, because the clouds are optically thin and most missions have performed surface-focussed nadir sounding, geographic and seasonal coverage is sparse. We present new detections of mesospheric clouds using a limb spectra dataset with global coverage acquired by NASA's Mars Climate Sounder (MCS) aboard Mars Reconnaissance Orbiter. Mesospheric aerosol layers, which can be CO2 ice, water ice or dust clouds, cause high radiances in limb spectra, either by thermal emission or scattering of sunlight. We employ an object recognition and classification algorithm to identify and map aerosol layers in limb spectra acquired between December 2006 and April 2011, covering more than two Mars years. We use data from MCS band A4, to show thermal signatures of day and nightside features, and A6, which is sensitive to short wave IR and visible daytime features only. This large dataset provides several thousand detections of mesospheric clouds, more than an order of magnitude more than in previous studies. Our results show that aerosol layers tend to occur in two distinct regimes. They form in equatorial regions (30°S-30°N) during the aphelion season/northern hemisphere summer (Ls 150°) a greater number of features are observed and are distributed in two mid-latitude bands, with a southern hemisphere bias. We observe temporal and longitudinal clustering of cloud occurrence, which we suggest is consistent with a formation mechanism dictated by interaction of broad temperature regimes imposed by global circulation and the propagation to the mesosphere of small-scale dynamics such as gravity waves and thermal tides. Using calculated frost point temperatures and a parameterization based on synthetic spectra we find that aphelion clouds are present in generally cooler conditions and are spectrally more consistent with H2O or CO2 ice. A significant fraction has nearby temperature retrievals that are

  4. Dry Climate as Major Factor Controlling Formation of Hydrated Sulfate Minerals in Valles Marineris on Mars

    Science.gov (United States)

    Szynkiewicz, A.

    2016-12-01

    In this study, a model for the formation of hydrated sulfate salts (Mg-Ca-Na sulfates) in the Rio Puerco watershed of New Mexico, a terrestrial analog site from the semi-arid Southwest U.S., was used to assess the origin and climate condition that may have controlled deposition of hydrated sulfates in Valles Marineris on Mars. In this analog site, the surface accumulation of sulfate minerals along canyon walls, slopes and valley surfaces closely resemble occurrences of hydrated sulfates in Valles Marineris on Mars. Significant surface accumulations of Mg-Ca-Na sulfates are a result of prevailing semiarid conditions and a short-lived hydrological cycle that mobilizes sulfur present in the bedrock as sulfides, sulfate minerals, and atmospheric deposition. Repeating cycles of salt dissolution and re-precipitation appear to be the underpinning processes that serve to transport sulfate from bedrock to sulfate salts (e.g., efflorescences) and into surface water. This process occurs in the shallow surface environment and is not accompanied by deep groundwater flow because of prevailing dry conditions and low annual precipitation. Generally, close resemblance of surface occurrence and mineralogical composition of sulfate salts between the studied terrestrial analog and Valles Marineris suggest that a similar sulfate cycle, involving limited water activity during formation of hydrated sulfates, was once present in Valles Marineris. Measured as efflorescence, the distributed surface mass of hydrated sulfates in Valles Marineris is relatively small (4 to 42%) when compared to terrestrial settings with higher surface accumulation of sulfate minerals such as the White Sands gypsum dune field. Under semi-arid conditions similar to the studied analog in the Rio Pueurco watershed, it would take only 100 to 1,000 years to activate an equivalent flux of aqueous sulfate in Valles Marineris, when comparing terrestrial annual sulfate fluxes from the Rio Puerco watershed with the amount

  5. Improved sea level record over the satellite altimetry era (1993-2010) from the Climate Change Initiative project

    DEFF Research Database (Denmark)

    Ablain, M.; Cazenave, A.; Larnicol, G.;

    2015-01-01

    Sea level is one of the 50 Essential Climate Variables (ECVs) listed by the Global Climate Observing System (GCOS) in climate change monitoring. In the past two decades, sea level has been routinely measured from space using satellite altimetry techniques. In order to address a number of importan...

  6. Web-Based Satellite Products Database for Meteorological and Climate Applications

    Science.gov (United States)

    Phan, Dung; Spangenberg, Douglas A.; Palikonda, Rabindra; Khaiyer, Mandana M.; Nordeen, Michele L.; Nguyen, Louis; Minnis, Patrick

    2004-01-01

    The need for ready access to satellite data and associated physical parameters such as cloud properties has been steadily growing. Air traffic management, weather forecasters, energy producers, and weather and climate researchers among others can utilize more satellite information than in the past. Thus, it is essential that such data are made available in near real-time and as archival products in an easy-access and user friendly environment. A host of Internet web sites currently provide a variety of satellite products for various applications. Each site has a unique contribution with appeal to a particular segment of the public and scientific community. This is no less true for the NASA Langley's Clouds and Radiation (NLCR) website (http://www-pm.larc.nasa.gov) that has been evolving over the past 10 years to support a variety of research projects This website was originally developed to display cloud products derived from the Geostationary Operational Environmental Satellite (GOES) over the Southern Great Plains for the Atmospheric Radiation Measurement (ARM) Program. It has evolved into a site providing a comprehensive database of near real-time and historical satellite products used for meteorological, aviation, and climate studies. To encourage the user community to take advantage of the site, this paper summarizes the various products and projects supported by the website and discusses future options for new datasets.

  7. Snow and firn density variability on the Greenland and Antarctic Ice Sheets from observations, the MAR regional climate model, and the RACMO firn model

    Science.gov (United States)

    Alexander, P. M.; Koenig, L.; Datta, R.; Tedesco, M.; Kuipers Munneke, P.; Ligtenberg, S.; Fettweis, X.; van den Broeke, M.

    2015-12-01

    The density of snow and firn of the Greenland and Antarctic Ice Sheets (GrIS and AIS) is an important parameter in ice sheet surface mass balance (SMB). Snow and firn densities are needed to convert satellite- and airborne-derived snow thickness changes into surface mass changes. Moreover, density directly impacts SMB by influencing the amount of liquid water that can be stored in firn and snow at the ice sheet surface. Using recently updated density profiles from the SUMup community dataset, we examine spatial and temporal variations in measured densities over the GrIS and AIS, and evaluate modeled profiles from the Modèle Atmosphérique Régionale (MAR) RCM and the firn model of the Regional Atmospheric Climate Model (RACMO2). The MAR model tends to underestimate densities in the first meter of the snowpack over both ice sheets, although the biases are spatially variable. We provide results regarding the relationship between modeled biases and parameters such as the time and location of the sample profile, and climatology at the profile location. We also explore whether recent increases in surface air temperature and melting over the Greenland ice have led to changes in simulated density profiles.

  8. Utilizing Satellite Precipitation Products to Understand the Link Between Climate Variability and Malaria

    Science.gov (United States)

    Maggioni, V.; Mousam, A.; Delamater, P. L.; Cash, B. A.; Quispe, A.

    2015-12-01

    Malaria is a public health threat to people globally leading to 198 million cases and 584,000 deaths annually. Outbreaks of vector borne diseases such as malaria can be significantly impacted by climate variables such as precipitation. For example, an increase in rainfall has the potential to create pools of water that can serve as breeding locations for mosquitos. Peru is a country that is currently controlling malaria, but has not been able to completely eliminate the disease. Despite the various initiatives in order to control malaria - including regional efforts to improve surveillance, early detection, prompt treatment, and vector management - malaria cases in Peru have risen between 2011 and 2014. The purpose of this study is to test the hypothesis that climate variability plays a fundamental role in malaria occurrence over a 12-year period (2003-2014) in Peru. When analyzing climate variability, it is important to obtain high-quality, high-resolution data for a time series long enough to draw conclusion about how climate variables have been and are changing. Remote sensing is a powerful tool for measuring and monitoring climate variables continuously in time and space. A widely used satellite-based precipitation product, the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA), available globally since 1998, was used to obtain 3-hourly data with a spatial resolution of 0.25° x 0.25°. The precipitation data was linked to weekly (2003-2014) malaria cases collected by health centers and available at a district level all over Peru to investigate the relationship between precipitation and the seasonal and annual variations in malaria incidence. Further studies will incorporate additional climate variables such as temperature, humidity, soil moisture, and surface pressure from remote sensing data products and climate models. Ultimately, this research will help us to understand if climate variability impacts malaria incidence

  9. Potential and limitations of multidecadal satellite soil moisture observations for selected climate model evaluation studies

    Directory of Open Access Journals (Sweden)

    A. Loew

    2013-09-01

    Full Text Available Soil moisture is an essential climate variable (ECV of major importance for land–atmosphere interactions and global hydrology. An appropriate representation of soil moisture dynamics in global climate models is therefore important. Recently, a first multidecadal, observation-based soil moisture dataset has become available that provides information on soil moisture dynamics from satellite observations (ECVSM, essential climate variable soil moisture. The present study investigates the potential and limitations of this new dataset for several applications in climate model evaluation. We compare soil moisture data from satellite observations, reanalysis and simulations from a state-of-the-art land surface model and analyze relationships between soil moisture and precipitation anomalies in the different dataset. Other potential applications like model parameter optimization or model initialization are not investigated in the present study. In a detailed regional study, we show that ECVSM is capable to capture well the interannual and intraannual soil moisture and precipitation dynamics in the Sahelian region. Current deficits of the new dataset are critically discussed and summarized at the end of the paper to provide guidance for an appropriate usage of the ECVSM dataset for climate studies.

  10. Implementing earth observation and advanced satellite based atmospheric sounders for water resource and climate modelling

    DEFF Research Database (Denmark)

    Boegh, E.; Dellwik, Ebba; Hahmann, Andrea N.;

    This paper discusses preliminary remote sensing (MODIS) based hydrological modelling results for the Danish island Sjælland (7330 km2) in relation to project objectives and methodologies of a new research project “Implementing Earth observation and advanced satellite based atmospheric sounders...... for effective land surface representation in water resource modeling” (2009- 2012). The purpose of the new research project is to develop remote sensing based model tools capable of quantifying the relative effects of site-specific land use change and climate variability at different spatial scales....... For this purpose, a) internal catchment processes will be studied using a Distributed Temperature Sensing (DTS) system, b) Earth observations will be used to upscale from field to regional scales, and c) at the largest scale, satellite based atmospheric sounders and meso-scale climate modelling will be used...

  11. Environmental Satellites: Strategy Needed to Sustain Critical Climate and Space Weather Measurements

    Science.gov (United States)

    2010-04-01

    together. For example, climate measurements have allowed scientists to better understand the effect of deforestation on how the earth absorbs heat, retains...Geostationary Operational Environmental Satellites: Progress Has Been Made, but Improvements Are Needed to Effectively Manage Risks, GAO-08-18 (Washington...color; and atmospheric observations such as greenhouse gas levels (e.g., carbon dioxide), aerosol and dust particles, and moisture concentration. When

  12. Improved sea level record over the satellite altimetry era (1993-2010) from the Climate Change Initiative project

    DEFF Research Database (Denmark)

    Ablain, M.; Cazenave, A.; Larnicol, G.

    2015-01-01

    Sea level is one of the 50 Essential Climate Variables (ECVs) listed by the Global Climate Observing System (GCOS) in climate change monitoring. In the past two decades, sea level has been routinely measured from space using satellite altimetry techniques. In order to address a number of importan...... present preliminary independent validations of the SL_cci products, based on tide gauges comparison and a sea level budget closure approach, as well as comparisons with ocean reanalyses and climate model outputs....

  13. In Situ Atmospheric Pressure Measurements in the Martian Southern Polar Region: Mars Volatiles and Climate Surveyor Meteorology Package on the Mars Polar Lander

    Science.gov (United States)

    Harri, A.-M.; Polkko, J.; Siili, T.; Crisp, D.

    1998-01-01

    Pressure observations are crucial for the success of the Mars Volatiles and Climate Surveyor (MVACS) Meteorology (MET) package onboard the Mars Polar Lander (MPL), due for launch early next year. The spacecraft is expected to land in December 1999 (L(sub s) = 256 degrees) at a high southern latitude (74 degrees - 78 degrees S). The nominal period of operation is 90 sols but may last up to 210 sols. The MVACS/MET experiment will provide the first in situ observations of atmospheric pressure, temperature, wind, and humidity in the southern hemisphere of Mars and in the polar regions. The martian atmosphere goes through a large-scale atmospheric pressure cycle due to the annual condensation/sublimation of the atmospheric CO2. Pressure also exhibits short period variations associated with dust storms, tides, and other atmospheric events. A series of pressure measurements can hence provide us with information on the large-scale state and dynamics of the atmosphere, including the CO2 and dust cycles as well as local weather phenomena. The measurements can also shed light on the shorter time scale phenomena (e.g., passage of dust devils) and hence be important in contributing to our understanding of mixing and transport of heat, dust, and water vapor.

  14. Combining Satellite and in Situ Data with Models to Support Climate Data Records in Ocean Biology

    Science.gov (United States)

    Gregg, Watson

    2011-01-01

    The satellite ocean color data record spans multiple decades and, like most long-term satellite observations of the Earth, comes from many sensors. Unfortunately, global and regional chlorophyll estimates from the overlapping missions show substantial biases, limiting their use in combination to construct consistent data records. SeaWiFS and MODIS-Aqua differed by 13% globally in overlapping time segments, 2003-2007. For perspective, the maximum change in annual means over the entire Sea WiFS mission era was about 3%, and this included an El NinoLa Nina transition. These discrepancies lead to different estimates of trends depending upon whether one uses SeaWiFS alone for the 1998-2007 (no significant change), or whether MODIS is substituted for the 2003-2007 period (18% decline, P less than 0.05). Understanding the effects of climate change on the global oceans is difficult if different satellite data sets cannot be brought into conformity. The differences arise from two causes: 1) different sensors see chlorophyll differently, and 2) different sensors see different chlorophyll. In the first case, differences in sensor band locations, bandwidths, sensitivity, and time of observation lead to different estimates of chlorophyll even from the same location and day. In the second, differences in orbit and sensitivities to aerosols lead to sampling differences. A new approach to ocean color using in situ data from the public archives forces different satellite data to agree to within interannual variability. The global difference between Sea WiFS and MODIS is 0.6% for 2003-2007 using this approach. It also produces a trend using the combination of SeaWiFS and MODIS that agrees with SeaWiFS alone for 1998-2007. This is a major step to reducing errors produced by the first cause, sensor-related discrepancies. For differences that arise from sampling, data assimilation is applied. The underlying geographically complete fields derived from a free-running model is unaffected

  15. Very high resolution surface mass balance over Greenland modeled by the regional climate model MAR with a downscaling technique

    Science.gov (United States)

    Kittel, Christoph; Lang, Charlotte; Agosta, Cécile; Prignon, Maxime; Fettweis, Xavier; Erpicum, Michel

    2016-04-01

    This study presents surface mass balance (SMB) results at 5 km resolution with the regional climate MAR model over the Greenland ice sheet. Here, we use the last MAR version (v3.6) where the land-ice module (SISVAT) using a high resolution grid (5km) for surface variables is fully coupled while the MAR atmospheric module running at a lower resolution of 10km. This online downscaling technique enables to correct near-surface temperature and humidity from MAR by a gradient based on elevation before forcing SISVAT. The 10 km precipitation is not corrected. Corrections are stronger over the ablation zone where topography presents more variations. The model has been force by ERA-Interim between 1979 and 2014. We will show the advantages of using an online SMB downscaling technique in respect to an offline downscaling extrapolation based on local SMB vertical gradients. Results at 5 km show a better agreement with the PROMICE surface mass balance data base than the extrapolated 10 km MAR SMB results.

  16. Observing upper troposphere-lower stratosphere climate with radio occultation data from the CHAMP satellite

    Energy Technology Data Exchange (ETDEWEB)

    Foelsche, Ulrich; Borsche, Michael; Steiner, Andrea K.; Gobiet, Andreas; Pirscher, Barbara; Kirchengast, Gottfried [University of Graz, Wegener Center for Climate and Global Change (WegCenter) and Institute for Geophysics, Astrophysics, and Meteorology (IGAM), Graz (Austria); Wickert, Jens; Schmidt, Torsten [GeoForschungsZentrum Potsdam (GFZ), Potsdam (Germany)

    2008-07-15

    High quality observations of the atmosphere are particularly required for monitoring global climate change. Radio occultation (RO) data, using Global Navigation Satellite System (GNSS) signals, are well suited for this challenge. The special climate utility of RO data arises from their long-term stability due to their self-calibrated nature. The German research satellite CHAllenging Minisatellite Payload for geoscientific research (CHAMP) continuously records RO profiles since August 2001 providing the first opportunity to create RO based climatologies for a multi-year period of more than 5 years. A period of missing CHAMP data from July 3, 2006 to August 8, 2006 can be bridged with RO data from the GRACE satellite (Gravity Recovery and Climate Experiment). We have built seasonal and zonal mean climatologies of atmospheric (dry) temperature, microwave refractivity, geopotential height and pressure with 10 latitudinal resolution. We show representative results with focus on dry temperatures and compare them with analysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF). Although we have available only about 150 CHAMP profiles per day (compared to millions of data entering the ECMWF analyses) the overall agreement between 8 and 30 km altitude is in general very good with systematic differences <0.5 K in most parts of the domain. Pronounced systematic differences (exceeding 2 K) in the tropical tropopause region and above Antarctica in southern winter can almost entirely be attributed to errors in the ECMWF analyses. Errors resulting from uneven sampling in space and time are a potential error source for single-satellite climatologies. The average CHAMP sampling error for seasonal zonal means is <0.2 K, higher values occur in restricted regions and time intervals which can be clearly identified by the sampling error estimation approach we introduced (which is based on ECMWF analysis fields). The total error of this new type of temperature

  17. Climate change on Mars and the formation of gullies, lobate debris aprons, and softened craters

    Science.gov (United States)

    Parsons, Reid Allen

    Recent data acquired from spacecraft missions has bettered our understanding of the nature and distribution of ice- and water-related features formed during recent periods of climate change on Mars. Numerical modeling of physical processes constrained by these newly acquired observations is an important tool with which hypotheses relating to the Martian climate can be tested. This work describes the development and implementation of a set of these models focused on the formation of a few young, ice- and water-related features. The subjects of this research are gullies, lobate debris aprons (LDAs), and craters with subdued topography known as "softened" craters. Flow of liquid water and ice over and/or within the Martian surface has been invoked in the formation of these features. Quantifying processes such as fluvial erosion and ice deformation using laboratory experiments is a Rosetta stone with which we can read into the climate history of Mars that is written on its surface. We test the hypothesis that sediment transport on gully slopes occurs via fluvial transport processes by developing a numerical sediment transport model based on steep flume experiments performed by Smart [1984]. At 20° slopes, channels 1 m deep by 8m wide and 0.1 m deep by 3 m wide transport a sediment volume equal to the alcove volume of 6 x 105 m3 in 10 hours and 40 days, respectively, under constant flow conditions. Snowpack melting cannot produce the water discharge rates necessary for fluvial sediment transport, unless long-term (kyr) storage of the resulting meltwater occurs. If these volumes of water are discharged as groundwater, the required aquifer thicknesses and aquifer drawdown lengths would be unrealistically large for a single discharge event. More plausibly, the water volume required by the fluvial transport model could be discharged in ˜ 10 episodes for an aquifer 30 m thick, with a recurrence interval similar to that of Martian obliquity cycles (˜0.1 My). Radar

  18. Assessment of radiative feedback in climate models using satellite observations of annual flux variation.

    Science.gov (United States)

    Tsushima, Yoko; Manabe, Syukuro

    2013-05-07

    In the climate system, two types of radiative feedback are in operation. The feedback of the first kind involves the radiative damping of the vertically uniform temperature perturbation of the troposphere and Earth's surface that approximately follows the Stefan-Boltzmann law of blackbody radiation. The second kind involves the change in the vertical lapse rate of temperature, water vapor, and clouds in the troposphere and albedo of the Earth's surface. Using satellite observations of the annual variation of the outgoing flux of longwave radiation and that of reflected solar radiation at the top of the atmosphere, this study estimates the so-called "gain factor," which characterizes the strength of radiative feedback of the second kind that operates on the annually varying, global-scale perturbation of temperature at the Earth's surface. The gain factor is computed not only for all sky but also for clear sky. The gain factor of so-called "cloud radiative forcing" is then computed as the difference between the two. The gain factors thus obtained are compared with those obtained from 35 models that were used for the fourth and fifth Intergovernmental Panel on Climate Change assessment. Here, we show that the gain factors obtained from satellite observations of cloud radiative forcing are effective for identifying systematic biases of the feedback processes that control the sensitivity of simulated climate, providing useful information for validating and improving a climate model.

  19. Investigating Mars South Residual CO2 Cap with a Global Climate Model

    Science.gov (United States)

    Kahre, M. A.; Dequaire, J.; Hollingsworth, J. L.; Haberle, R. M.

    2016-01-01

    The CO2 cycle is one of the three controlling climate cycles on Mars. One aspect of the CO2 cycle that is not yet fully understood is the existence of a residual CO2 ice cap that is offset from the south pole. Previous investigations suggest that the atmosphere may control the placement of the south residual cap (e.g., Colaprete et al., 2005). These investigations show that topographically forced stationary eddies in the south during southern hemisphere winter produce colder atmospheric temperatures and increased CO2 snowfall over the hemisphere where the residual cap resides. Since precipitated CO2 ice produces higher surface albedos than directly deposited CO2 ice, it is plausible that CO2 snowfall resulting from the zonally asymmetric atmospheric circulation produces surface ice albedos high enough to maintain a residual cap only in one hemisphere. The goal of the current work is to further evaluate Colaprete et al.'s hypothesis by investigating model-predicted seasonally varying snowfall patterns in the southern polar region and the atmospheric circulation components that control them.

  20. Vegetation coupling to global climate: Trajectories of vegetation change and phenology modeling from satellite observations

    Science.gov (United States)

    Fisher, Jeremy Isaac

    Important systematic shifts in ecosystem function are often masked by natural variability. The rich legacy of over two decades of continuous satellite observations provides an important database for distinguishing climatological and anthropogenic ecosystem changes. Examples from semi-arid Sudanian West Africa and New England (USA) illustrate the response of vegetation to climate and land-use. In Burkina Faso, West Africa, pastoral and agricultural practices compete for land area, while degradation may follow intensification. The Nouhao Valley is a natural experiment in which pastoral and agricultural land uses were allocated separate, coherent reserves. Trajectories of annual net primary productivity were derived from 18 years of coarse-grain (AVHRR) satellite data. Trends suggested that pastoral lands had responded rigorously to increasing rainfall after the 1980's droughts. A detailed analysis at Landsat resolution (30m) indicated that the increased vegetative cover was concentrated in the river basins of the pastoral region, implying a riparian wood expansion. In comparison, riparian cover was reduced in agricultural regions. We suggest that broad-scale patterns of increasing semi-arid West African greenness may be indicative of climate variability, whereas local losses may be anthropogenic in nature. The contiguous deciduous forests, ocean proximity, topography, and dense urban developments of New England provide an ideal landscape to examine influences of climate variability and the impact of urban development vegetation response. Spatial and temporal patterns of interannual climate variability were examined via green leaf phenology. Phenology, or seasonal growth and senescence, is driven by deficits of light, temperature, and water. In temperate environments, phenology variability is driven by interannual temperature and precipitation shifts. Average and interannual phenology analyses across southern New England were conducted at resolutions of 30m (Landsat

  1. A simplified satellite navigation system for an autonomous Mars roving vehicle.

    Science.gov (United States)

    Janosko, R. E.; Shen, C. N.

    1972-01-01

    The use of a retroflecting satellite and a laser rangefinder to navigate a Martian roving vehicle is considered in this paper. It is shown that a simple system can be employed to perform this task. An error analysis is performed on the navigation equations and it is shown that the error inherent in the scheme proposed can be minimized by the proper choice of measurement geometry. A nonlinear programming approach is used to minimize the navigation error subject to constraints that are due to geometric and laser requirements. The problem is solved for a particular set of laser parameters and the optimal solution is presented.

  2. PlanetServer: Innovative approaches for the online analysis of hyperspectral satellite data from Mars

    Science.gov (United States)

    Oosthoek, J. H. P.; Flahaut, J.; Rossi, A. P.; Baumann, P.; Misev, D.; Campalani, P.; Unnithan, V.

    2014-06-01

    PlanetServer is a WebGIS system, currently under development, enabling the online analysis of Compact Reconnaissance Imaging Spectrometer (CRISM) hyperspectral data from Mars. It is part of the EarthServer project which builds infrastructure for online access and analysis of huge Earth Science datasets. Core functionality consists of the rasdaman Array Database Management System (DBMS) for storage, and the Open Geospatial Consortium (OGC) Web Coverage Processing Service (WCPS) for data querying. Various WCPS queries have been designed to access spatial and spectral subsets of the CRISM data. The client WebGIS, consisting mainly of the OpenLayers javascript library, uses these queries to enable online spatial and spectral analysis. Currently the PlanetServer demonstration consists of two CRISM Full Resolution Target (FRT) observations, surrounding the NASA Curiosity rover landing site. A detailed analysis of one of these observations is performed in the Case Study section. The current PlanetServer functionality is described step by step, and is tested by focusing on detecting mineralogical evidence described in earlier Gale crater studies. Both the PlanetServer methodology and its possible use for mineralogical studies will be further discussed. Future work includes batch ingestion of CRISM data and further development of the WebGIS and analysis tools.

  3. Satellite remotely-sensed land surface parameters and their climatic effects for three metropolitan regions

    Science.gov (United States)

    Xian, George

    2008-01-01

    By using both high-resolution orthoimagery and medium-resolution Landsat satellite imagery with other geospatial information, several land surface parameters including impervious surfaces and land surface temperatures for three geographically distinct urban areas in the United States – Seattle, Washington, Tampa Bay, Florida, and Las Vegas, Nevada, are obtained. Percent impervious surface is used to quantitatively define the spatial extent and development density of urban land use. Land surface temperatures were retrieved by using a single band algorithm that processes both thermal infrared satellite data and total atmospheric water vapor content. Land surface temperatures were analyzed for different land use and land cover categories in the three regions. The heterogeneity of urban land surface and associated spatial extents were shown to influence surface thermal conditions because of the removal of vegetative cover, the introduction of non-transpiring surfaces, and the reduction in evaporation over urban impervious surfaces. Fifty years of in situ climate data were integrated to assess regional climatic conditions. The spatial structure of surface heating influenced by landscape characteristics has a profound influence on regional climate conditions, especially through urban heat island effects.

  4. The Strengths and Limitations of Satellite Data for Evaluating Tropospheric Processes in Chemistry-Climate Models

    Science.gov (United States)

    Duncan, Bryan

    2012-01-01

    There is now a wealth of satellite data products available with which to evaluate a model fs simulation of tropospheric composition and other model processes. All of these data products have their strengths and limitations that need to be considered for this purpose. For example, uncertainties are introduced into a data product when 1) converting a slant column to a vertical column and 2) estimating the amount of a total column of a trace gas (e.g., ozone, nitrogen dioxide) that resides in the troposphere. Oftentimes, these uncertainties are not well quantified and the satellite data products are not well evaluated against in situ observations. However, these limitations do not preclude us from using these data products to evaluate our model processes if we understand these strengths and limitations when developing diagnostics. I will show several examples of how satellite data products are being used to evaluate particular model processes with a focus on the strengths and limitations of these data products. In addition, I will introduce the goals of a newly formed team to address issues on the topic of "satellite data for improved model evaluation and process studies" that is established in support of the IGAC/SPARC Global Chemistry ]Climate Modeling and Evaluation Workshop.

  5. Gray Wave of the Great Transformation: A Satellite View of Urbanization, Climate Change, and Food Security

    Science.gov (United States)

    Imhoff, Marc Lee; Kamiell, Arnon Menahem

    2010-01-01

    Land cover change driven by human activity is profoundly affecting Earth's natural systems with impacts ranging from a loss of biological diversity to changes in regional and global climate. This change has been so pervasive and progressed so rapidly, compared to natural processes, scientists refer to it as "the great transformation". Urbanization or the 'gray wave' of land transformation is being increasingly recognized as an important process in global climate change. A hallmark of our success as a species, large urban conglomerates do in fact alter the land surface so profoundly that both local climate and the basic ecology of the landscape are affected in ways that have consequences to human health and economic well-being. Fortunately we have incredible new tools for planning and developing urban places that are both enjoyable and sustainable. A suite of Earth observing satellites is making it possible to study the interactions between urbanization, biological processes, and weather and climate. Using these Earth Observatories we are learning how urban heat islands form and potentially ameliorate them, how urbanization can affect rainfall, pollution, and surface water recharge at the local level and climate and food security globally.

  6. Multiple satellite estimates of urban fractions and climate effects at regional scale

    Science.gov (United States)

    Jia, G.; Xu, R.; He, Y.

    2014-12-01

    Regional climate is controlled by large scale forcing at lateral boundary and physical processes within the region. Landuse in East Asia has been changed substantially in the last three decades, featured with expansion of urban built-up at unprecedented scale and speed. The fast expansion of urban areas could contribute to local even regional climate change. However, current spatial datasets of urban fractions do not well represent extend and expansion of urban areas in the regions, and the best available satellite data and remote sensing techniques have not been well applied to serve regional modeling of urbanization impacts on near surface temperature and other climate variables. Better estimates of localized urban fractions and urban climate effects are badly needed. Here we use high and mid resolution satellite data to estimate urban fractions and to assess effects of urban heat islands at local and regional scales. With our fractional cover, data fusion, and differentiated threshold approaches, estimated urban extent was greater than previously reported in many global datasets. Many city clusters were merging into each other, with gradual blurring boundaries and disappearing of gaps among member cities. Cities and towns were more connected with roads and commercial corridors, while wildland and urban greens became more isolated as patches among built-up areas. Those new estimates are expected to effectively improve climate simulation at local and regional scales in East Asia. There were significant positive relations between urban fraction and urban heat island effects as demonstrated by VNIR and TIR data from multiple satellites. Stronger warming was detected at the meteorological stations that experienced greater urbanization, i.e., those with a higher urbanization rate. While the total urban area affects the absolute temperature values, the change of the urban area (urbanization rate) likely affects the temperature trend. Increases of approximately 10% in

  7. Satellite altimetry reveals spatial patterns of variations in the Baltic Sea wave climate

    Science.gov (United States)

    Kudryavtseva, Nadezhda; Soomere, Tarmo

    2017-08-01

    The main properties of the climate of waves in the seasonally ice-covered Baltic Sea and its decadal changes since 1990 are estimated from satellite altimetry data. The data set of significant wave heights (SWHs) from all existing nine satellites, cleaned and cross-validated against in situ measurements, shows overall a very consistent picture. A comparison with visual observations shows a good correspondence with correlation coefficients of 0.6-0.8. The annual mean SWH reveals a tentative increase of 0.005 m yr-1, but higher quantiles behave in a cyclic manner with a timescale of 10-15 years. Changes in the basin-wide average SWH have a strong meridional pattern: an increase in the central and western parts of the sea and a decrease in the east. This pattern is likely caused by a rotation of wind directions rather than by an increase in the wind speed.

  8. Simulation of land surface temperatures: comparison of two climate models and satellite retrievals

    Directory of Open Access Journals (Sweden)

    J. M. Edwards

    2009-03-01

    Full Text Available Recently there has been significant progress in the retrieval of land surface temperature from satellite observations. Satellite retrievals of surface temperature offer several advantages, including broad spatial coverage, and such data are potentially of great value in assessing general circulation models of the atmosphere. Here, retrievals of the land surface temperature over the contiguous United States are compared with simulations from two climate models. The models generally simulate the diurnal range realistically, but show significant warm biases during the summer. The models' diurnal cycle of surface temperature is related to their surface flux budgets. Differences in the diurnal cycle of the surface flux budget between the models are found to be more pronounced than those in the diurnal cycle of surface temperature.

  9. Climate Change Impacts and Vulnerabilities Assessment on Forest Vegetation Through Time-Series Multisensor Satellite Data

    Science.gov (United States)

    Zoran, Maria; Savastru, Dan; Dida, Adrian

    2016-08-01

    Sustaining forest resources in Romania requires a better understanding of forest ecosystem processes, and how management decisions and climate and anthropogenic change may affect these processes in the future. Spatio- temporal forest vegetation dynamics have been quantified as the total amount of vegetation (mean NDVI) and the seasonal difference (annual NDVI amplitude) by a time series analysis of NDVI LAI satellite images over 2000 - 2015 period for a forest ecosystem placed in the North-Eastern part of Bucharest town, Romania, from MODIS Terra/Aqua, LANDSAT TM/ETM and Sentinel satellite and meteorological data. For investigated test area, considerable NDVI decline was observed for drought events during 2003, 2007 and 2010 years. Under stress conditions, it is evident that environmental factors such as soil type, parent material, and topography are not correlated with NDVI dynamics. EO-based estimates of forest biophysical variables were shown to be similar to predictions derived from forest field inventories.

  10. Gridded sunshine duration climate data record for Germany based on combined satellite and in situ observations

    Science.gov (United States)

    Walawender, Jakub; Kothe, Steffen; Trentmann, Jörg; Pfeifroth, Uwe; Cremer, Roswitha

    2017-04-01

    The purpose of this study is to create a 1 km2 gridded daily sunshine duration data record for Germany covering the period from 1983 to 2015 (33 years) based on satellite estimates of direct normalised surface solar radiation and in situ sunshine duration observations using a geostatistical approach. The CM SAF SARAH direct normalized irradiance (DNI) satellite climate data record and in situ observations of sunshine duration from 121 weather stations operated by DWD are used as input datasets. The selected period of 33 years is associated with the availability of satellite data. The number of ground stations is limited to 121 as there are only time series with less than 10% of missing observations over the selected period included to keep the long-term consistency of the output sunshine duration data record. In the first step, DNI data record is used to derive sunshine hours by applying WMO threshold of 120 W/m2 (SDU = DNI ≥ 120 W/m2) and weighting of sunny slots to correct the sunshine length between two instantaneous image data due to cloud movement. In the second step, linear regression between SDU and in situ sunshine duration is calculated to adjust the satellite product to the ground observations and the output regression coefficients are applied to create a regression grid. In the last step regression residuals are interpolated with ordinary kriging and added to the regression grid. A comprehensive accuracy assessment of the gridded sunshine duration data record is performed by calculating prediction errors (cross-validation routine). "R" is used for data processing. A short analysis of the spatial distribution and temporal variability of sunshine duration over Germany based on the created dataset will be presented. The gridded sunshine duration data are useful for applications in various climate-related studies, agriculture and solar energy potential calculations.

  11. Signals of astronomical climate forcing in the exposure topography of the North Polar Layered Deposits of Mars

    Science.gov (United States)

    Becerra, Patricio; Sori, Michael M.; Byrne, Shane

    2017-01-01

    Using high-resolution topography, we link the stratigraphy of layered ice deposits at the north pole of Mars to astronomically driven climate variability. Observations of trough exposures within these deposits are used to construct virtual ice cores at 16 sites, to which we apply wavelet analysis to identify periodicities in layer properties. To confidently relate these periodicities to climatic forcing, we identify overlapping dominant stratigraphic wavelengths and compare their ratios to that of the two dominant modes of insolation variability. The average ratio of stratigraphic wavelengths in the profiles is 1.9 ± 0.1, lower than the ratio of 2.3 between dominant insolation periodicities. A similar analysis of synthetic stratigraphic profiles created with a climate-driven model of ice and dust accumulation shows that this lower stratigraphic ratio is a natural consequence of time-variable ice accumulation rates.

  12. Estimating the Greenland ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR

    NARCIS (Netherlands)

    Fettweis, X.; Franco, B.; Tedesco, M.; van Angelen, J.H.; Lenaerts, J.T.M.; van den Broeke, M.R.; Gallée, H.

    2013-01-01

    To estimate the sea level rise (SLR) originating from changes in surface mass balance (SMB) of the Greenland ice sheet (GrIS), we present 21st century climate projections obtained with the regional climate model MAR (Mod`ele Atmosph´erique R´egional), forced by output of three CMIP5 (Coupled Model I

  13. SNC Meteorites: Atmosphere Implantation Ages and the Climatic Evolution of Mars

    Science.gov (United States)

    Moyano-Cambero, C. E.; Trigo-Rodríguez, Josep M.; Martín-Torres, F. Javier

    SNC meteorites are Martian rocks that provide valuable information about the atmospheric composition of Mars over time. These meteorites experienced significant shock during the impact that released them from Mars, and during the flight through the Martian atmosphere some of the gases were retained in the melted shock-altered glasses. As using different radiogenic systems can precisely date such shock processes, SNC achondrites can be considered time capsules capable of providing significant insight into the atmospheric evolution of Mars. Different SNCs were released by impacts at different times, having then different atmosphere-implantation ages, so in practice we can obtain clues on the composition of Mars' atmosphere at different times. Taking this information into account, we have developed a 1D model of the evolution of Martian Mars' atmosphere mass, near surface temperature and pressure.

  14. Advancing Coastal Climate Adaptation in Denmark by Land Subsidence Mapping using Sentinel-1 Satellite Imagery

    DEFF Research Database (Denmark)

    Sørensen, Carlo Sass; Broge, Niels H.; Mølgaard, Mads R.

    2016-01-01

    There are still large uncertainties in projections of climate change and sea level rise. Here, land subsidence is an additional factor that may adversely affect the vulnerability towards floods in low-lying coastal communities. The presented study performs an initial assessment of subsidence...... mapping using Sentinel-1 satellite imagery and leveling at two coastal locations in Denmark. Within both investigated areas current subsidence rates of 5-10 millimeters per year are found. This subsidence is related to the local geology, and challenges and potentials in bringing land subsidence mapping...... and geology into climate adaptation are discussed in relation to perspectives of a national subsidence monitoring system partly based on the findings from the two coastal locations. The current lack of subsidence data and a fragmentation of geotechnical information are considered as hindrances to optimal...

  15. Climate model biases in seasonally of continental water storage revealed by satellite gravimetry

    Science.gov (United States)

    Swenson, S.C.; Milly, P.C.D.

    2006-01-01

    Satellite gravimetric observations of monthly changes in continental water storage are compared with outputs from five climate models. All models qualitatively reproduce the global pattern of annual storage amplitude, and the seasonal cycle of global average storage is reproduced well, consistent with earlier studies. However, global average agreements mask systematic model biases in low latitudes. Seasonal extrema of low-latitude, hemispheric storage generally occur too early in the models, and model-specific errors in amplitude of the low-latitude annual variations are substantial. These errors are potentially explicable in terms of neglected or suboptimally parameterized water stores in the land models and precipitation biases in the climate models. Copyright 2006 by the American Geophysical Union.

  16. Comparing wind directions inferred from Martian dust devil tracks analysis with those predicted by the Mars Climate Database

    Science.gov (United States)

    Statella, T.; Pina, P.; Silva, E. A.; Nervis Frigeri, Ary Vinicius; Neto, Frederico Gallon

    2016-10-01

    We have calculated the prevailing dust devil tracks direction as a means of verifying the Mars Climate Database (MCD) predicted wind directions accuracy. For that purpose we have applied an automatic method based on morphological openings for inferring the prevailing tracks direction in a dataset comprising 200 Mars Orbiter Camera (MOC) Narrow Angle (NA) and High Resolution Imaging Science Experiment (HiRISE) images of the Martian surface, depicting regions in the Aeolis, Eridania, Noachis, Argyre and Hellas quadrangles. The prevailing local wind directions were calculated from the MCD predicted speeds for the WE and SN wind components. The results showed that the MCD may not be able to predict accurately the locally dominant wind direction near the surface. In adittion, we confirm that the surface wind stress alone cannot produce dust lifting in the studied sites, since it never exceeds the threshold value of 0.0225 Nm-2 in the MCD.

  17. Estimating Greenland ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR

    Directory of Open Access Journals (Sweden)

    X. Fettweis

    2012-08-01

    Full Text Available We report future projections of Surface Mass Balance (SMB over the Greenland ice sheet (GrIS obtained with the regional climate model MAR, forced by the outputs of three CMIP5 General Circulation Models (GCMs when considering two different warming scenarios (RCP 4.5 and RCP 8.5. The GCMs selected in this study have been chosen according to their ability to simulate the current climate over Greenland. Our results indicate that in a warmer climate (i the mass gained due to increased precipitation over GrIS does not compensate the mass lost through increased run-off; (ii the surface melt increases non-linearly with rising temperatures due to the positive feedback between surface albedo and melt, associated with the expansion of bare ice zones which, in addition, decreases the ice sheet refreezing capacity; (iii most of the precipitation is expected to fall as rainfall in summer, which further increases surface melt; (iv no considerable change is expected on the length of the melting season, since heavier winter snowfall dampens the melt increase at the end of spring; (v the increase of meltwater run-off versus temperature anomalies is dependent of the GCM-forced MAR ability to simulate the current climate; (vi the MAR-simulated SMB changes can be approximated using the annual accumulated snowfall and summer 600 hPa temperature increase simulated by the forcing GCMs. In view of the large range in the CMIP5 future projections for the same future scenario, the GCM-based SMB approximations allow us to estimate what future projections are most likely within the CMIP5 multi-model ensemble. In 2100, the ensemble mean projects a sea level rise, resulting from a GrIS SMB decrease, estimated to be +4 ± 2 cm and +9 ± 4 cm for the RCP 4.5 and RCP 8.5 scenarios, respectively. The GrIS SMB should remain positive with respect to RCP 4.5 scenario and becomes negative around 2070 in the case of the RCP 8.5 scenario since a global warming >+3 °C is needed

  18. Satellite-based assessment of climate controls on US burned area

    Directory of Open Access Journals (Sweden)

    D. C. Morton

    2012-06-01

    Full Text Available Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate-fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA, the Global Fire Emissions Database (GFED, 1997–2010 and Monitoring Trends in Burn Severity (MTBS, 1984–2009 BA products. For each US National Climate Assessment (NCA region, we analyzed the relationships between monthly BA and potential evaporation (PE derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE} and fire activity in the Alaska, while water deficit (precipitation – PE was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6–12 months. Fire season PE increased from the 1980s–2000s, enhancing climate-driven fire risk in the southern and western US where PE-BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990s–2000s highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the diversity of

  19. Satellite-based assessment of climate controls on US burned area

    Science.gov (United States)

    Morton, D. C.; Collatz, G. J.; Wang, D.; Randerson, J. T.; Giglio, L.; Chen, Y.

    2013-01-01

    Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate-fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA), the Global Fire Emissions Database (GFED, 1997-2010) and Monitoring Trends in Burn Severity (MTBS, 1984-2009) BA products. For each US National Climate Assessment (NCA) region, we analyzed the relationships between monthly BA and potential evaporation (PE) derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for the entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE and fire activity in Alaska, while water deficit (precipitation - PE) was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6-12 months). Fire season PE increased from the 1980's-2000's, enhancing climate-driven fire risk in the southern and western US where PE-BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990's-2000's highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the diversity of fire types

  20. Rainfall variability over southern Africa: an overview of current research using satellite and climate model data

    Science.gov (United States)

    Williams, C.; Kniveton, D.; Layberry, R.

    2009-04-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. In this research, satellite-derived rainfall data are used as a basis for undertaking model experiments using a state-of-the-art climate model, run at both high and low spatial resolution. Once the model's ability to reproduce extremes has been assessed, idealised regions of sea surface temperature (SST) anomalies are used to force the model, with the overall aim of investigating the ways in which SST anomalies influence rainfall extremes over southern Africa. In this paper, a brief overview is given of the authors' research to date, pertaining to southern African rainfall. This covers (i) a description of present-day rainfall variability over southern Africa; (ii) a comparison of model simulated daily rainfall with the satellite-derived dataset; (iii) results from sensitivity testing of the model's domain size; and (iv) results from the idealised SST experiments.

  1. Future projections of the Greenland ice sheet energy balance driving the surface melt, developed using the regional climate MAR model

    Directory of Open Access Journals (Sweden)

    B. Franco

    2012-07-01

    Full Text Available In this study, 25 km-simulations are performed over the Greenland ice sheet (GrIS throughout the 20th and 21st centuries, using the regional climate model MAR forced by four RCP scenarios from two CMIP5 global circulation models, in order to investigate the projected changes of the surface energy balance (SEB components driving the surface melt. Analysis of 2000–2100 melt anomalies compared to melt results over 1980–1999 reveals an exponential relationship of the GrIS surface melt rate simulated by MAR to the near-surface temperature (TAS anomalies, mainly due to the surface albedo positive feedback associated with the extension of bare ice areas in summer. On the GrIS margins, the future melt anomalies are rather driven by stronger sensible heat fluxes, induced by enhanced warm air advections over the ice sheet. Over the central dry snow zone, the increase of melt surpasses the negative feedback from heavier snowfall inducing therefore a decrease of the summer surface albedo even at the top of the ice sheet. In addition to the incoming longwave flux increase associated to the atmosphere warming, MAR projects an increase of the cloud cover decreasing the ratio of the incoming shortwave versus longwave radiation and dampening the albedo feedback. However, it should be noted that this trend in the cloud cover is contrary to that simulated by ERA-INTERIM-forced MAR over current climate, where the observed melt increase since the 1990's seems rather to be a consequence of more anticyclonic atmospheric conditions. Finally, no significant change is projected in the length of the melt season. This timing highlights the importance of solar radiation in the melt SEB.

  2. Satellite-based assessment of climate controls on US burned area

    Directory of Open Access Journals (Sweden)

    D. C. Morton

    2013-01-01

    Full Text Available Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate–fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA, the Global Fire Emissions Database (GFED, 1997–2010 and Monitoring Trends in Burn Severity (MTBS, 1984–2009 BA products. For each US National Climate Assessment (NCA region, we analyzed the relationships between monthly BA and potential evaporation (PE derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for the entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE and fire activity in Alaska, while water deficit (precipitation – PE was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6–12 months. Fire season PE increased from the 1980's–2000's, enhancing climate-driven fire risk in the southern and western US where PE–BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990's–2000's highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the

  3. Assessment of soil moisture fields from imperfect climate models with uncertain satellite observations

    Directory of Open Access Journals (Sweden)

    G. Schumann

    2009-03-01

    Full Text Available We demonstrate that global satellite products can be used to evaluate climate model soil moisture predictions but conclusions should be drawn with care. The quality of a limited area climate model (LAM was compared to a general circulation model (GCM using soil moisture data from two different Earth observing satellites within a model validation scheme that copes with the presence of uncertain data. Results showed that in the face of imperfect models and data, it is difficult to investigate the quality of current land surface schemes in simulating hydrology accurately. Nevertheless, a LAM provides, in general, a better representation of spatial patterns and dynamics of soil moisture. However, in months when data uncertainty is higher, particularly in colder months and in periods when vegetation cover and soil moisture are out of phase (e.g. August in the case of Western Europe, it is not possible to draw firm conclusions about model acceptability. Our work indicates that a higher resolution LAM has more benefits to soil moisture prediction than are due to the resolution alone and can be attributed to an overall intensification of the hydrological cycle relative to the GCM.

  4. Characterization of interfade duration for satellite communication systems design and optimization in a temperate climate

    Science.gov (United States)

    Jorge, Flávio; Riva, Carlo; Rocha, Armando

    2016-03-01

    The characterization of the fade dynamics on Earth-satellite links is an important subject when designing the so called fade mitigation techniques that contribute to the proper reliability of the satellite communication systems and the customers' quality of service (QoS). The interfade duration, defined as the period between two consecutive fade events, has been only poorly analyzed using limited data sets, but its complete characterization would enable the design and optimization of the satellite communication systems by estimating the system requirements to recover in time before the next propagation impairment. Depending on this analysis, several actions can be taken ensuring the service maintenance. In this paper we present for the first time a detailed and comprehensive analysis of the interfade events statistical properties based on 9 years of in-excess attenuation measurements at Ka band (19.7 GHz) with very high availability that is required to build a reliable data set mainly for the longer interfade duration events. The number of years necessary to reach the statistical stability of interfade duration is also evaluated for the first time, providing a reference when accessing the relevance of the results published in the past. The study is carried out in Aveiro, Portugal, which is conditioned by temperate Mediterranean climate with Oceanic influences.

  5. Soil Moisture Drought Monitoring and Forecasting Using Satellite and Climate Model Data over Southwestern China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xuejun; Tang, Qiuhong; Liu, Xingcai; Leng, Guoyong; Li, Zhe

    2017-01-01

    Real-time monitoring and predicting drought development with several months in advance is of critical importance for drought risk adaptation and mitigation. In this paper, we present a drought monitoring and seasonal forecasting framework based on the Variable Infiltration Capacity (VIC) hydrologic model over Southwest China (SW). The satellite precipitation data are used to force VIC model for near real-time estimate of land surface hydrologic conditions. As initialized with satellite-aided monitoring, the climate model-based forecast (CFSv2_VIC) and ensemble streamflow prediction (ESP)-based forecast (ESP_VIC) are both performed and evaluated through their ability in reproducing the evolution of the 2009/2010 severe drought over SW. The results show that the satellite-aided monitoring is able to provide reasonable estimate of forecast initial conditions (ICs) in a real-time manner. Both of CFSv2_VIC and ESP_VIC exhibit comparable performance against the observation-based estimates for the first month, whereas the predictive skill largely drops beyond 1-month. Compared to ESP_VIC, CFSv2_VIC shows better performance as indicated by the smaller ensemble range. This study highlights the value of this operational framework in generating near real-time ICs and giving a reliable prediction with 1-month ahead, which has great implications for drought risk assessment, preparation and relief.

  6. In Situ Sedimentological Evidence for Climate Change in Early Mars Provided by the Curiosity Rover in Gale Crater

    Science.gov (United States)

    Heydari, Ezat; Fairen, Alberto G.

    2016-10-01

    The Striated formation is one of the rock units that was deposited in Gale crater, Mars, during the Late Noachian to Hesperian time (4.2 to 3.6 billion years ago). It crops out for 3 km along the Curiosity's traverse. The Striated formation strikes N65○E and has a depositional dip of 10○ - 20○ to SE. It consists of 500 m to 1000 m of highly rhythmic layers each 1 m to 4 m in thickness. Study of MAHLI and MastCam images provided by the Curiosity Rover indicates that layers form fining-upward cycles consisting of thick-bedded to massive conglomerate at the base that grades upward to thinly bedded conglomerate, then to pebbly sandstone, and topped by laminated, fine grained sandstone. Layers show slump folds, soft sediment deformation, and cross-beddings.The highly rhythmic occurrence and the fining-upward grain size characteristic indicate that each layer within the Striated formation is a coarse-grained turbidite: a type of rock that forms when sediments move down-hill by gravity-driven turbidity flows and deposit in deep waters. We propose that turbidite layers of the Striated formation are related to delivery of sediments to Gale crater by megafloods through its northern rim. Upon entering Gale crater, sediments moved down-hill and deposited as turbidite layers when the crater may have been filled to the rim with water. About 1000 to 3000 turbidite layers are present suggesting the occurrences of as many megafloods during hothouse climatic intervals when Mars was warmer than the Present and had plenty of liquid water. Floods were generated by one or a combination of the following processes: (1) torrential rain along the margins of Mars's Northern Ocean, 500 km to 1000 km to the north, (2) rapid melting of ice in highland areas, and (3) tsunamis formed by impacts on the Northern Ocean. Cold and/or dry climate of icehouse intervals may have followed each warming episode. Mars's climate forcing mechanism and periodicities of climate change are not clear at this

  7. Interannual Variability of Tropical Precipitation: How Well Do Climate Models Agree With Current Satellite Estimates?

    Science.gov (United States)

    Robertson, Franklin R.; Marshall, Susan; Roads, John; Oglesby, Robert J.; Fitzjarrald, Dan; Goodman, H. Michael (Technical Monitor)

    2001-01-01

    Since the beginning of the World Climate Research Program's Global Precipitation Climatology Project (GPCP) satellite remote sensing of precipitation has made dramatic improvements, particularly for tropical regions. Data from microwave and infrared sensors now form the most critical input to precipitation data sets and can be calibrated with surface gauges to so that the strengths of each data source can be maximized in some statistically optimal sense. Recent availability of the TRMM (Tropical Rainfall Measuring Mission) has further aided in narrowing uncertainties in rainfall over die tropics and subtropics. Although climate modeling efforts have long relied on space-based precipitation estimates for validation, we now are in a position to make more quantitative assessments of model performance, particularly in tropical regions. An integration of the CCM3 using observed SSTs as a lower boundary condition is used to examine how well this model responds to ENSO forcing in terms of anomalous precipitation. An integration of the NCEP spectral model used for the Reanalysis-H effort is also examined. This integration is run with specified SSTs, but with no data assimilation. Our analysis focuses on two aspects of inter-annual variability. First are the spatial anomalies that are indicative of dislocations in Hadley and Walker circulations. Second, we consider the ability of models to replicate observed increases in oceanic precipitation that are noted in satellite observations for large ENSO events. Finally, we consider a slab ocean version of the CCM3 model with prescribed ocean beat transports that mimic upwelling anomalies, but which still allows the surface energy balance to be predicted. This less restrictive experiment is used to understand why model experiments with specified SSTs seem to have noticeably less interannual variability in precipitation than do the satellite observations.

  8. Earth Radiation Imbalance from a Constellation of 66 Iridium Satellites: Climate Science Aspects

    Science.gov (United States)

    Wiscombe, W.; Chiu, CJ. Y.

    2012-01-01

    The "global warming hiatus" since the 1998 El Nino, highlighted by Meehl et al., and the resulting "missing energy" problem highlighted by Trenberth et al., has opened the door to a more fundamental view of climate change than mere surface air temperature. That new view is based on two variables which are strongly correlated: the rate of change of ocean heat content d(OHC)/dt; and Earth Radiation Imbalance (ERI) at the top of the atmosphere, whose guesstimated range is 0.4 to 0.9 Watts per square meters (this imbalance being mainly due to increasing CO2). The Argo float array is making better and better measurements of OHC. But existing satellite systems cannot measure ERI to even one significant digit. So, climate model predictions of ERI are used in place of real measurements of it, and the satellite data are tuned to the climate model predictions. Some oceanographers say "just depend on Argo for understanding the global warming hiatus and the missing energy", but we don't think this is a good idea because d(OHC)/dt and ERI have different time scales and are never perfectly correlated. We think the ERB community needs to step up to measuring ERI correctly, just as oceanographers have deployed Argo to measure OHC correctly. This talk will overview a proposed constellation of 66 Earth radiation budget instruments, hosted on Iridium satellites, that will actually be able to measure ERI to at least one significant digit, thus enabling a crucial test of climate models. This constellation will also be able to provide ERI at two-hourly time scales and 500-km spatial scales without extrapolations from uncalibrated narrowband geostationary instruments, using the highly successful methods of GRACE to obtain spatial resolution. This high time resolution would make ERI a synoptic variable like temperature, and allow studies of ERI's response to fast-evolving phenomena like dust storms and hurricanes and even brief excursions of Total Solar Irradiance. Time permitting, we

  9. Deriving required model structures to predict global wildfire burned area from multiple satellite and climate observations

    Science.gov (United States)

    Forkel, Matthias; Dorigo, Wouter; Lasslop, Gitta; Teubner, Irene; Chuvieco, Emilio; Thonicke, Kirsten

    2017-04-01

    Vegetation fires have important effects on human infrastructures and ecosystems, and affect atmospheric composition and the climate system. Consequently, it is necessary to accurately represent fire dynamics in global vegetation models to realistically represent the role of fires in the Earth system. However, it is unclear which model structures are required in global vegetation/fire models to represent fire activity at regional to global scales. Here we aim to identify required structural components and necessary complexities of global vegetation/fire models to predict spatial-temporal dynamics of burned area. For this purpose, we developed the SOFIA (satellite observations for fire activity) modelling approach to predict burned area from several satellite and climate datasets. A large ensemble of SOFIA models was generated and each model was optimized against observed burned area data. Models that account for a suppression of fire activity at wet conditions result in the highest performances in predicting burned area. Models that include vegetation optical depth data from microwave satellite observations reach higher performances in predicting burned area than models that do not include this dataset. Vegetation optical depth is a proxy for vegetation biomass, density and water content and thus indicates a strong control of vegetation states and dynamics on fire activity. We further compared the best performing SOFIA models with the global process-oriented vegetation/fire model JSBACH-SPITFIRE, and with the GFED and Fire_CCI burned area datasets. SOFIA models outperform JSBACH-SPITFIRE in predicting regional variabilities of burned area. We further applied the best SOFIA model to identify controlling factors for burned area. The results indicate that fire activity is controlled by regionally diverse and complex interactions of human, vegetation and climate factors. Our results demonstrate that the use of multiple observational datasets on climate, hydrological

  10. Secular Climate Change on Mars: An Update Using MSL Pressure Data

    Science.gov (United States)

    Haberle, R. M.; Gomez-Elvira, J.; Juarez, M. de la Torre; Harri, A.-M.; Hollingsworth, J. L.; Kahanpaa, H.; Kahre, M. A.; Lemmon, M.; Martin-Torres, F. J.; Mischna, M.; Moores, J. E.; Newman, C.; Rafkin, S. C. R.; Renno, N.; Richardson, M. I.; Rodriguez-Manfredi, J. A.; Thomas, P.; Vasavada, A. R.; Wong, M. H.; Zorzano-Mier, M.-P.

    2013-01-01

    The South Polar Residual Cap (SPRC) on Mars is an icy reservoir of CO2. If all the CO2 trapped in the SPRC were released to the atmosphere the mean annual global surface pressure would rise by approx. 20 Pa. Repeated MOC and HiRISE imaging of scarp retreat rates within the SPRC have led to the suggestion that the SPRC is losing mass. Estimates for the loss rate vary between 0.5 Pa per Mars Deacde to 13 Pa per Mars Decade. Assuming 80% of this loss goes directly to the atmosphere, and that the loss is monotonic, the global annual mean surface pressure should have increased between approx. 1-20 Pa since the Viking mission (19 Mars years ago).

  11. Examining Traveling Waves in Mars Atmosphere Reanalyses

    Science.gov (United States)

    Greybush, Steven J.; Wilson, R. John

    2015-11-01

    Synoptic-scale eddies (traveling waves) are a key feature of the variability of Mars atmosphere weather in the extratropics, and are linked to the initiation of dust storms. Mars reanalyses, which combine satellite observations with simulations from a Mars Global Climate Model (MGCM), provide a four-dimensional picture of the evolution of these waves in terms of temperature, winds, pressure, and aerosol fields. The Ensemble Mars Atmosphere Reanalysis System (EMARS) has created multiple years of Mars weather maps through the assimilation of Thermal Emission Spectrometer (TES) and Mars Climate Sounder (MCS) temperature profiles using the ensemble Kalman filter and the GFDL MGCM. We investigate the robustness of the synoptic eddies to changes in the aerosol fields, model parameters, data assimilation system design, and observation dataset (TES vs. MCS). We examine the evolution of wavenumber regimes, their seasonal evolution, and interannual variability. Finally, reanalysis fields are combined with spacecraft visible imagery (e.g. MGS Mars Orbital Camera), demonstrating the link between meteorological fields (temperature, pressure, and wind) and dust fronts.

  12. Complexity in Climatic Controls on Plant Species Distribution: Satellite Data Reveal Unique Climate for Giant Sequoia in the California Sierra Nevada

    OpenAIRE

    Waller, Eric Kindseth

    2014-01-01

    ABSTRACTComplexity in Climatic Controls on Plant Species Distribution: Satellite Data Reveal Unique Climate for Giant Sequoia in the California Sierra NevadabyEric Kindseth WallerDoctor of Philosophy in Environmental Science, Policy, and ManagementUniversity of California, BerkeleyProfessor Dennis D. Baldocchi, ChairA better understanding of the environmental controls on current plant species distribution is essential if the impacts of such diverse challenges as invasive species, changing fir...

  13. Grid-Mapping of Hellas Planitia, Mars - Geostatistical Analyses of Cold-Climate Landforms

    Science.gov (United States)

    Voelker, Martin; Hauber, Ernst; Jaumann, Ralf

    2016-10-01

    Hellas Planitia is one of the largest impact basins on Mars, with a diameter of 2,300 km and located in the southern mid-latitudes. The basin also contains the topographically lowest parts of the planet, making it of special interest for water and ice-related geomorphological activities. We applied a Grid-Mapping method to analyze the geographical distribution of possibly ice-related landforms (e.g., latitude-dependent mantle [LDM] and scalloped terrain) in a visual and statistical manner. Thus, we are able to look for yet unrecognized correlations between the landforms themselves and external parameters such as elevation, slope inclination, slope aspect (azimuth), and thermal inertia.By using this method, the study area is separated into 20,100 grids, each 20×20 km. Mapping is based on CTX images at a scale of 1:30,000 in a GIS environment. Because of the huge size of the study area, only every second grid has been mapped. For 21 different landforms, we attributed one of the five following classes to each grid: "dominant", "present", "possible", "absent", and "no data". The non-mapped grids were interpolated later. Statistical calculations have only considered "dominant" and "present" values for reliable results. In normalized distribution diagrams only bins with more than 30 samples are shown.Despite LDM covers Hellas almost entirely, our map shows an elliptical 800×200 km gap in NE Hellas. We suggest this lack of LDM may be the result of the dominant wind circulation pattern within the basin. According to global climate models, cold south-polar wind currents enter Hellas at a breach in its SW rim and rotate clockwise in Hellas. When they reach the northern parts of the Hellas floor around 30°S they warm up, and begin to move south again, subliming or preventing the evolution of LDM in the NE portions of Hellas because of the higher air temperature. In contrast to LDM, scalloped terrain occurs on higher inclined slopes between 6° to 9°. As they are

  14. Satellite cloud and precipitation property retrievals for climate monitoring and hydrological applications

    Science.gov (United States)

    Wolters, E. L. A.

    2012-03-01

    This thesis presents the retrieval, evaluation, and application of cloud physical property datasets (cloud phase, cloud particle effective radius, and precipitation occurrence and intensity) obtained from Spinning Enhanced Visible and Infrared Imager (SEVIRI) reflectance measurements using the Cloud Physical Properties (CPP) retrieval algorithm. In Chapter 3 it is shown that the CPP cloud-phase retrieval algorithm has sufficient accuracy (West Africa. During the afternoon, precipitation occurrence frequency over dry soils becomes significantly higher than over wet soils, whereas for precipitation intensity no significant difference is discerned. The study demonstrates that the combination of satellite-based soil moisture and precipitation observations can be helpful in improving the understanding of the land surface-precipitation interaction over tropical areas. The thesis concludes with a number of recommendations on future algorithm improvements and potential research applications. For both cloud phase and precipitation properties, extension of the algorithm to include nighttime observations would be desirable to enable detailed studies on the full diurnal cycle. Further, the SEVIRI High-Resolution Visible (HRV) channel could be incorporated to correct retrieved cloud physical properties for broken and inhomogeneous cloud cases. Finally, the accurate cloud phase and precipitation datasets combined with the high SEVIRI spatial and temporal sampling resolution enables possibilities for detailed research on climate monitoring, nowcasting applications, evaluation of cloud schemes in climate models, studies on land surface-precipitation interactions (with a special focus on the diurnal cycle), and assimilation of the datasets in weather and climate models

  15. Several thoughts for using new satellite remote sensing and global modeling for aerosol and cloud climate studies

    Science.gov (United States)

    Nakajima, Teruyuki; Hashimoto, Makiko; Takenaka, Hideaki; Goto, Daisuke; Oikawa, Eiji; Suzuki, Kentaroh; Uchida, Junya; Dai, Tie; Shi, Chong

    2017-04-01

    The rapid growth of satellite remote sensing technologies in the last two decades widened the utility of satellite data for understanding climate impacts of aerosols and clouds. The climate modeling community also has received the benefit of the earth observation and nowadays closed-collaboration of the two communities make us possible to challenge various applications for societal problems, such as for global warming and global-scale air pollution and others. I like to give several thoughts of new algorithm developments, model use of satellite data for climate impact studies and societal applications related with aerosols and clouds. Important issues are 1) Better aerosol detection and solar energy application using expanded observation ability of the third generation geostationary satellites, i.e. Himawari-8, GOES-R and future MTG, 2) Various observation functions by directional, polarimetric, and high resolution near-UV band by MISR, POLDER&PARASOL, GOSAT/CAI and future GOSAT2/CAI2, 3) Various applications of general purpose-imagers, MODIS, VIIRS and future GCOM-C/SGLI, and 4) Climate studies of aerosol and cloud stratification and convection with active and passive sensors, especially climate impact of BC aerosols using CLOUDSAT&CALIPSO and future Earth Explorer/EarthCARE.

  16. Mars Atmosphere and Volatile EvolutioN (MAVEN) mission's Red Planet program: Bridging the gap in elementary school science through climate studies of Mars

    Science.gov (United States)

    Wood, E. L.

    2012-12-01

    Although reading, writing, and math examinations are often conducted early in elementary school, science is not typically tested until 4th or 5th grade. The result is a refocus on the tested topics at the expense of the untested ones, despite that standards exist for each topic at all grades. On a national level, science instruction is relegated to a matter of a few hours per week. A 2007 Education Policy study states that elementary school students spend an average of 178 minutes a week on science while spending 500 minutes on literacy. A recent NSTA report in July of 2011 of elementary and middle school teachers confirms that teachers feel pressured to teach math and literacy at the expense of other programs. In our interaction with elementary teachers, it is also apparent that many are uncomfortable with science concepts. In order for us to successfully address the Next Generation Science Standards, teachers must be able to reconcile all of the different requirements placed on them in a given school day and in a given school environment. A unique way to combat the lack of science instruction at elementary grades is to combine literacy into an integrated science program, thereby increasing the number of science contact hours. The Red Planet: Read, Write, Explore program, developed for the MAVEN mission, is a science, art, and literacy program designed to easily fit into a typical 3rd-5th grade instructional day. Red Planet tackles climate change through Mars' geologic history and makes Mars-Earth comparisons, while encouraging students to reflect on the environmental requirements needed to keep a biological organisms (including humans) happy, healthy, and alive. The Red Planet program is currently being pilot tested at Acres Green Elementary School in Colorado.

  17. SAT-MAP-CLIMATE project results[SATellite base bio-geophysical parameter MAPping and aggregation modelling for CLIMATE models

    Energy Technology Data Exchange (ETDEWEB)

    Bay Hasager, C.; Woetmann Nielsen, N.; Soegaard, H.; Boegh, E.; Hesselbjerg Christensen, J.; Jensen, N.O.; Schultz Rasmussen, M.; Astrup, P.; Dellwik, E.

    2002-08-01

    Earth Observation (EO) data from imaging satellites are analysed with respect to albedo, land and sea surface temperatures, land cover types and vegetation parameters such as the Normalized Difference Vegetation Index (NDVI) and the leaf area index (LAI). The observed parameters are used in the DMI-HIRLAM-D05 weather prediction model in order to improve the forecasting. The effect of introducing actual sea surface temperatures from NOAA AVHHR compared to climatological mean values, shows a more pronounced land-sea breeze effect which is also observable in field observations. The albedo maps from NOAA AVHRR are rather similar to the climatological mean values so for the HIRLAM model this is insignicant, yet most likely of some importance in the HIRHAM regional climate model. Land cover type maps are assigned local roughness values determined from meteorological field observations. Only maps with a spatial resolution around 25 m can adequately map the roughness variations of the typical patch size distribution in Denmark. A roughness map covering Denmark is aggregated (ie area-average non-linearly) by a microscale aggregation model that takes the non-linear turbulent responses of each roughness step change between patches in an arbitrary pattern into account. The effective roughnesses are calculated into a 15 km by 15 km grid for the HIRLAM model. The effect of hedgerows is included as an added roughness effect as a function of hedge density mapped from a digital vector map. Introducing the new effective roughness maps into the HIRLAM model appears to remedy on the seasonal wind speed bias over land and sea in spring. A new parameterisation on the effective roughness for scalar surface fluxes is developed and tested on synthetic data. Further is a method for the estimation the evapotranspiration from albedo, surface temperatures and NDVI succesfully compared to field observations. The HIRLAM predictions of water vapour at 12 GMT are used for atmospheric correction of

  18. Extratropical Cyclogenesis and Frontal Waves on Mars: Influences on Dust, Weather and the Planet's climate

    Science.gov (United States)

    Hollingsworth, J. L.; Kahre, Melinda A.

    2012-01-01

    Between late autumn and early spring, middle and high latitudes on Mars exhibit strong equatortopole mean temperature contrasts (i.e., "baroclinicity"). Data collected during the Viking era and observations from both the Mars Global Surveyor (MGS) and Mars Reconnaissance Orbiter (MRO) indicate that this strong baroclinicity supports vigorous, large-scale eastward traveling weather systems (i.e., transient synoptic periodwaves) [1,2]. For a rapidly rotating, differentially heated, shallow atmosphere such as on Earth and Mars, these large-scale, extratropical weather disturbances are critical components of the global circulation. The wavelike disturbances act as agents in the transport of heat and momentum between low and high latitudes of the planet. Through cyclonic/anticyclonic winds, intense shear deformations, contractions-dilatations in temperature and density, and sharp perturbations amongst atmospheric tracers (i.e., dust, volatiles (e.g., water vapor) and condensates (e.g., water-ice cloud particles)), Mars extratropical weather systems have significant subsynoptic scale ramifications by supporting atmospheric frontal waves (Fig. 1).

  19. Erosion rates at the Mars Exploration Rover landing sites and long-term climate change on Mars

    Science.gov (United States)

    Golombek, M.P.; Grant, J. A.; Crumpler, L.S.; Greeley, R.; Arvidson, R. E.; Bell, J.F.; Weitz, C.M.; Sullivan, R.J.; Christensen, P.R.; Soderblom, L.A.; Squyres, S. W.

    2006-01-01

    Erosion rates derived from the Gusev cratered plains and the erosion of weak sulfates by saltating sand at Meridiani Planum are so slow that they argue that the present dry and desiccating environment has persisted since the Early Hesperian. In contrast, sedimentary rocks at Meridiani formed in the presence of groundwater and occasional surface water, and many Columbia Hills rocks at Gusev underwent aqueous alteration during the Late Noachian, approximately coeval with a wide variety of geomorphic indicators that indicate a wetter and likely warmer environment. Two-toned rocks, elevated ventifacts, and perched and undercut rocks indicate localized deflation of the Gusev plains and deposition of an equivalent amount of sediment into craters to form hollows, suggesting average erosion rates of ???0.03 nm/yr. Erosion of Hesperian craters, modification of Late Amazonian craters, and the concentration of hematite concretions in the soils of Meridiani yield slightly higher average erosion rates of 1-10 nm/yr in the Amazonian. These erosion rates are 2-5 orders of magnitude lower than the slowest continental denudation rates on Earth, indicating that liquid water was not an active erosional agent. Erosion rates for Meridiani just before deposition of the sulfate-rich sediments and other eroded Noachian areas are comparable with slow denudation rates on Earth that are dominated by liquid water. Available data suggest the climate change at the landing sites from wet and likely warm to dry and desiccating occurred sometime between the Late Noachian and the beginning of the Late Hesperian (3.7-3.5 Ga). Copyright 2006 by the American Geophysical Union.

  20. The Destabilizing Effect of Water Ice Clouds in Mars Climate Models: Challenges and Solutions

    Science.gov (United States)

    Pottier, A.; Forget, F.; Montmessin, F.; Navarro, T.; Madeleine, J.-B.; Millour, E.; Spiga, A.

    2014-07-01

    Radiatively active water ice clouds in global climat models are very important to understand the martian climate and water cycle. However, challenges arise. Solution developed for the LMD GCM are presented: microphysics and subgrid scale nebulosity.

  1. Satellite observations of the role and impacts of dry season climate limitations on tropical forest fates

    Science.gov (United States)

    Huete, A. R.; Restrepo-Coupe, N.; Wu, J.; Devadas, R.; Guan, K.; Liu, Y.; Ratana, P.; Sun, Q.; Schaaf, C.; Saleska, S. R.

    2015-12-01

    Climate change scenarios projected for the 21st century predict drying of the Amazon, greening of monsoon tropical Asia and no change in the tropics of Australia. Dry season variability is increasing with complex associated forest responses and feedbacks as they become exposed to longer and/or more intense dry seasons. The functional response of tropical forests to dry seasonal periods is thus crucial to forest resilience, as forests may respond with either enhanced photosynthesis (due to more sunlight) or may dry down with greater susceptibility to fires and release of greenhouse gases and severe public health haze alerts. In this study, we use multiple satellite remote sensing datasets representing forest canopy states, environmental drivers (light and water status), and disturbance (fires), along with in situ flux tower measures of photosynthesis to assess whole ecosystem patterns and test mechanisms of forest- dry season climate interactions. We compare photosynthesis patterns and dry season responses of Asia-Oceania tropical forests with neotropical forests to better understand forest resilience to climate change and human impacts. In contrast to the neotropics, human activities in monsoon tropical Asia have resulted in intensive transformations of tropical forests. We find forest disturbance exerts a strong influence on tropical forest functioning and a partial loss or degradation of tropical forests can reverse dry seasonal responses with substantial impacts on carbon fluxes. Neotropical forests displayed large variations in dry season forest responses due to spatially variable dry season lengths and magnitude, whereas most of monsoon Asia tropical forests lacked well-defined dry seasons, yet were highly sensitive to shorter term, intense drought events that impacted severely upon the disturbed forests. Our results highlight the interactions among rainfall, radiation and forest health with the relative importance of each factor varying with the

  2. Mutual influence between climate and vegetation cover through satellite data in Egypt

    Science.gov (United States)

    El-Shirbeny, Mohammed A.; Aboelghar, Mohamed A.; Arafat, Sayed M.; El-Gindy, Abdel-Ghany M.

    2011-11-01

    The effect of vegetation cover on climatic change has not yet observed in Egypt. In the current study, Ismailia Governorate was selected as a case study to assess the impact of the vegetation cover expansion on both land surface and air temperature during twenty-eight years from 1983 to 2010. This observation site was carefully selected as a clear example for the highly rate of reclamation and vegetation expansion process in Egypt. Land Surface Temperature (LST) that were extracted from NOAA/AVHRR satellite data and air temperature (Tair) data that were collected from ground stations, were correlated with the expansion of vegetation cover that was delineated using Landsat TM and Landsat ETM+ data. The result showed that (LST) decreased by about 2.3°C while (Tair) decreased by about 1.6°C with the expansion of the cultivated land during twenty-eight years.

  3. Assessment and Comparison of TMPA Satellite Precipitation Products in Varying Climatic and Topographic Regimes in Morocco

    Directory of Open Access Journals (Sweden)

    Adam Milewski

    2015-05-01

    Full Text Available TRMM Multi-satellite Precipitation Analysis (TMPA satellite precipitation products have been utilized to quantify, forecast, or understand precipitation patterns, climate change, hydrologic models, and drought in numerous scientific investigations. The TMPA products recently went through a series of algorithm developments to enhance the accuracy and reliability of high-quality precipitation measurements, particularly in low rainfall environments and complex terrain. In this study, we evaluated four TMPA products (3B42: V6, V7temp, V7, RTV7 against 125 rain gauges in Northern Morocco to assess the accuracy of TMPA products in various regimes, examine the performance metrics of new algorithm developments, and assess the impact of the processing error in 2012. Results show that the research products outperform the real-time products in all environments within Morocco, and the newest algorithm development (3B42 V7 outperforms the previous version (V6, particularly in low rainfall and high-elevation environments. TMPA products continue to overestimate precipitation in arid environments and underestimate it in high-elevation areas. Lastly, the temporary processing error resulted in little bias except in arid environments. These results corroborate findings from previous studies, provide scientific data for the Middle East, highlight the difficulty of using TMPA products in varying conditions, and present preliminary research for future algorithm development for the GPM mission.

  4. Analysis of TRMM Satellite Data in Varying Climates and Elevation in Morocco

    Science.gov (United States)

    Milewski, A.; El Kadiri, R.; Durham, M.

    2012-12-01

    The use of satellite precipitation data (TRMM, SSM/I) in scientific investigations has been on the rise due to the general paucity or unavailability of adequate rain gauge data for the majority of the Earth's surface. Unfortunately, the number of research studies integrating TRMM data into various scientific applications (e.g., water resources, rainfall analysis, climate change, hydrologic modeling, etc.) has far outweighed those studying the accuracy, uncertainty, and usefulness of TRMM data. Even less research has been conducted on the viability of TRMM rainfall products as an adequate substitute for field gauges in data sparse and arid to semi-arid environments; the most critical area in need of satellite rainfall. An assessment on the accuracy and uncertainty of TRMM in these critical areas (ungauged basins, low rainfall) was conducted by comparing in-situ rain gauge stations in Northern Morocco against both the TRMM 3B42.v6 and recently processed 3B42.v7 precipitation products. We compared average annual precipitation values from 79 wide-spread field gauges in three watersheds (Oum Er Rbia, Sebou, Melouya Watersheds) originating in the Atlas Mountains to the TRMM datasets. In addition, we assessed the effect that different variables (elevation, climate regime, and season) have on both the version 6 and version 7 TRMM products. Gauges were divided into three elevation classes (Low: 0-500m; Medium: 500-1000m; High: >1000m) and precipitation/climate (Arid: 100-300mm/yr; Semi-Arid: 300-500mm/yr; Humid: >500mm/yr) classes to evaluate the impact of rainfall and elevation on satellite-based rainfall products. Results indicate that 3B42.v7 is more accurate than 3B42.v6 data using average annual precipitation data from 1998-2009 for the Oum Er Rbia Watershed (0.47 to 0.18 R2), however produces similar correlations for the 79 gauges combined (0.30 to 0.29 R2). The R2 values were improved using the version 7 products for the different elevation (Low: 0.30 v7 to 0.46 v6

  5. The High Resolution Stereo Camera (HRSC) of Mars Express and its approach to science analysis and mapping for Mars and its satellites

    Science.gov (United States)

    Gwinner, K.; Jaumann, R.; Hauber, E.; Hoffmann, H.; Heipke, C.; Oberst, J.; Neukum, G.; Ansan, V.; Bostelmann, J.; Dumke, A.; Elgner, S.; Erkeling, G.; Fueten, F.; Hiesinger, H.; Hoekzema, N. M.; Kersten, E.; Loizeau, D.; Matz, K.-D.; McGuire, P. C.; Mertens, V.; Michael, G.; Pasewaldt, A.; Pinet, P.; Preusker, F.; Reiss, D.; Roatsch, T.; Schmidt, R.; Scholten, F.; Spiegel, M.; Stesky, R.; Tirsch, D.; van Gasselt, S.; Walter, S.; Wählisch, M.; Willner, K.

    2016-07-01

    The High Resolution Stereo Camera (HRSC) of ESA's Mars Express is designed to map and investigate the topography of Mars. The camera, in particular its Super Resolution Channel (SRC), also obtains images of Phobos and Deimos on a regular basis. As HRSC is a push broom scanning instrument with nine CCD line detectors mounted in parallel, its unique feature is the ability to obtain along-track stereo images and four colors during a single orbital pass. The sub-pixel accuracy of 3D points derived from stereo analysis allows producing DTMs with grid size of up to 50 m and height accuracy on the order of one image ground pixel and better, as well as corresponding orthoimages. Such data products have been produced systematically for approximately 40% of the surface of Mars so far, while global shape models and a near-global orthoimage mosaic could be produced for Phobos. HRSC is also unique because it bridges between laser altimetry and topography data derived from other stereo imaging instruments, and provides geodetic reference data and geological context to a variety of non-stereo datasets. This paper, in addition to an overview of the status and evolution of the experiment, provides a review of relevant methods applied for 3D reconstruction and mapping, and respective achievements. We will also review the methodology of specific approaches to science analysis based on joint analysis of DTM and orthoimage information, or benefitting from high accuracy of co-registration between multiple datasets, such as studies using multi-temporal or multi-angular observations, from the fields of geomorphology, structural geology, compositional mapping, and atmospheric science. Related exemplary results from analysis of HRSC data will be discussed. After 10 years of operation, HRSC covered about 70% of the surface by panchromatic images at 10-20 m/pixel, and about 97% at better than 100 m/pixel. As the areas with contiguous coverage by stereo data are increasingly abundant, we also

  6. Complexity in Climatic Controls on Plant Species Distribution: Satellite Data Reveal Unique Climate for Giant Sequoia in the California Sierra Nevada

    Science.gov (United States)

    Waller, Eric Kindseth

    A better understanding of the environmental controls on current plant species distribution is essential if the impacts of such diverse challenges as invasive species, changing fire regimes, and global climate change are to be predicted and important diversity conserved. Climate, soil, hydrology, various biotic factors fire, history, and chance can all play a role, but disentangling these factors is a daunting task. Increasingly sophisticated statistical models relying on existing distributions and mapped climatic variables, among others, have been developed to try to answer these questions. Any failure to explain pattern with existing mapped climatic variables is often taken as a referendum on climate as a whole, rather than on the limitations of the particular maps or models. Every location has a unique and constantly changing climate so that any distribution could be explained by some aspect of climate. Chapter 1 of this dissertation reviews some of the major flaws in species distribution modeling and addresses concerns that climate may therefore not be predictive of, or even relevant to, species distributions. Despite problems with climate-based models, climate and climate-derived variables still have substantial merit for explaining species distribution patterns. Additional generation of relevant climate variables and improvements in other climate and climate-derived variables are still needed to demonstrate this more effectively. Satellite data have a long history of being used for vegetation mapping and even species distribution mapping. They have great potential for being used for additional climatic information, and for improved mapping of other climate and climate-derived variables. Improving the characterization of cloud cover frequency with satellite data is one way in which the mapping of important climate and climate-derived variables can be improved. An important input to water balance models, solar radiation maps could be vastly improved with a

  7. Ship and satellite observations over the ocean for verification of the shortwave cloud radiative effect in climate models

    Directory of Open Access Journals (Sweden)

    T. Hanschmann

    2012-07-01

    Full Text Available In this study the accuracy of the radiative transfer scheme of the ECHAM-5 climate model for reproducing the shortwave cloud radiative effect (SWCRE at the sea surface has been investigated. A characterization of both the observed state of the atmosphere and the surface radiation budget from ship and satellite is used for this purpose. The ship observations yield cloud fraction, liquid water path from a microwave radiometer, cloud bottom height as well as temperature and humidity profiles from radiosonde ascents. Level-2 products of the Satellite Application Facility on Climate Monitoring (CM-SAF from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI have been used to characterize clouds. Within a closure study six different experiments have been defined to find the optimal set of measurements to calculate downward shortwave radiation (DSR and the SWCRE from the model, and their results have been evaluated under seven different synoptic situations. Four of these experiments are defined to investigate the advantage of including the satellite-based cloud droplet effective radius as additional cloud property. The modeled SWCRE based on satellite retrieved cloud properties has a comparable accuracy to the modeled SWCRE based on ship data. For several cases, an improvement through introducing the satellite-based estimate of effective radius as additional information to the ship based data was found. Due to their different measuring characteristics, however, each dataset shows best results for different atmospheric conditions.

  8. CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate

    Science.gov (United States)

    Renno, N.; Williams, E.; Rosenfeld, D.; Fischer, D.; Fischer, J.; Kremic, T.; Agrawal, A.; Andreae, M.; Bierbaum, R.; Blakeslee, R.; Boerner, A.; Bowles, N.; Christian, H.; Dunion, J.; Horvath, A.; Huang, X.; Khain, A.; Kinne, S.; Lemos, M.-C.; Penner, J.

    2012-04-01

    The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. Knowledge of these interactions is foundational to our understanding of weather and climate. The Intergovernmental Panel on Climate Change (IPCC) and the Decadal Survey (NRC 2007) indicate that the uncertainty in how clouds adjust to aerosol perturbations dominates the uncertainty in the overall quantification of the radiative forcing attributable to human activities. The Clouds, Hazards, and Aerosols Survey for Earth Researchers (CHASER) mission concept responds to the IPCC and Decadal Survey concerns by studying the activation of CCN and their interactions with clouds and storms. CHASER proposes to revolutionize our understanding of the interactions of aerosols with clouds by making the first global measurements of the fundamental physical entity linking them: activated cloud condensation nuclei. The CHASER mission was conceptualized to measure all quantities necessary for determining the interactions of aerosols with clouds and storms. Measurements by current satellites allow the determination of crude profiles of cloud particle size but not of the activated CCN that seed them. CHASER uses a new technique (Freud et al. 2011; Rosenfeld et al. 2012) and high-heritage instruments to produce the first global maps of activated CCN and the properties of the clouds associated with them. CHASER measures the CCN concentration and cloud thermodynamic forcing simultaneously, allowing their effects to be distinguished. Changes in the behavior of a group of weather systems in which only one of the quantities varies (a partial derivative of the intensity with the desirable quantity) allow the determination of each effect statistically. The high uncertainties of current climate predictions limit their much-needed use in decision-making. CHASER mitigates this

  9. The South Polar Residual Cap and Secular Climate Change on Mars: What Can We Learn From Observations and Models?

    Science.gov (United States)

    Haberle, R. M.; Kahre, M.; Hollingsworth, J.; Barnes, J.; Forget, F.

    2009-12-01

    The prospect for multi-decadal secular climate change on Mars is a new concept that stems from observations of an apparently eroding South Polar Residual Cap (SPRC). Several years ago MOC images of the growth of circular depressions in the SPRC were interpreted to imply a net annual loss of approximately 2-10 x 10**9 m**3 of CO2 between 1999 and 2001 [1]. More recent studies using CTX images suggest a smaller loss, but one that is still potentially significant [2]. Taken together these data imply that if the all the CO2 sublimating from the SRPC goes into the atmosphere, as seems likely [3], an upper limit for the equivalent rate of increase in globally averaged surface pressure should be ~ 4 Pa per Mars Decade. About one and a half Mars decades have elapsed since the beginning of the Viking mission and the end of the Phoenix mission. If the net erosion of the SPRC has been steady during this period at the rate listed above, it would have produced about a 6 Pa increase in the global and annual mean surface pressure. Could such an increase be detected in the Viking and Phoenix pressure data? Clearly, this is a challenging question to answer, but one we feel needs careful examination. We report here the analysis of these data sets and the use of models to interpret them. Models are needed because surface pressure measurements at a few sites do not directly yield global mass budgets because dynamical processes and scale height changes influence surface pressure as well as seasonal exchange with the polar caps [4]. To reduce model uncertainties, we employ an ensemble of independently developed models including the NASA/Ames and LMD General Circulation Models, and the OSU MMM5 Mesoscale Model. References: [1] Malin, M.C. et al. (2001), Science, 294, 2146-2148. [2] Thomas, P. et al. (2009), Icarus, submitted. [3] Haberle, R.M. et al. (2009), 3rd International Workshop on Mars Polar Energy Balance and the CO2 Cycle (/http://www.lpi.usra.edu/meetings/mpeb2009). [4] Hourdin

  10. Satellite Observations and Chemistry Climate Models - A Meandering Path Towards Better Predictions

    Science.gov (United States)

    Douglass, Anne R.

    2011-01-01

    Knowledge of the chemical and dynamical processes that control the stratospheric ozone layer has grown rapidly since the 1970s, when ideas that depletion of the ozone layer due to human activity were put forth. The concept of ozone depletion due to anthropogenic chlorine increase is simple; quantification of the effect is much more difficult. The future of stratospheric ozone is complicated because ozone is expected to increase for two reasons: the slow decrease in anthropogenic chlorine due to the Montreal Protocol and its amendments and stratospheric cooling caused by increases in carbon dioxide and other greenhouse gases. Prediction of future ozone levels requires three-dimensional models that represent physical, photochemical and radiative processes, i.e., chemistry climate models (CCMs). While laboratory kinetic and photochemical data are necessary inputs for a CCM, atmospheric measurements are needed both to reveal physical and chemical processes and for comparison with simulations to test the conceptual model that CCMs represent. Global measurements are available from various satellites including but not limited to the LIMS and TOMS instruments on Nimbus 7 (1979 - 1993), and various instruments on the Upper Atmosphere Research Satellite (1991 - 2005), Envisat (2002 - ongoing), Sci-Sat (2003 - ongoing) and Aura (2004 - ongoing). Every successful satellite instrument requires a physical concept for the measurement, knowledge of physical chemical properties of the molecules to be measured, and stellar engineering to design an instrument that will survive launch and operate for years with no opportunity for repair but providing enough information that trend information can be separated from any instrument change. The on-going challenge is to use observations to decrease uncertainty in prediction. This talk will focus on two applications. The first considers transport diagnostics and implications for prediction of the eventual demise of the Antarctic ozone hole

  11. Assessment of the MAR regional climate model over the Antarctic Peninsula (1999 - 2009) through spaceborne enhanced spatial resolution melting maps and near-surface observations

    Science.gov (United States)

    Datta, R.; Tedesco, M.; Alexander, P. M.; Fettweis, X.; Steiner, N.; Gallee, H.

    2012-12-01

    We report results assessing the outputs of the regional climate model Modèle Atmosphérique Régionale (MAR) over the Antarctic peninsula for the period 1999 - 2009. Specifically, we compare maps of melt extent and duration generated by MAR with those obtained from the enhanced spatial resolution product (~ 5 km) distributed by the NASA Scatterometer Climate Record Pathfinder (SCP), at Brigham Young University (Utah, USA). Snowmelt is estimated from remote sensing observations using both a canonical threshold-based approach and a novel method based on wavelet methodology. MAR outputs are also evaluated against available surface observations (e.g., near-surface temperature, wind speed and direction, etc.). The additional effects of blowing snow upon the surface and energy balance can be uniquely explored by simulations in Antarctica (as compared to Greenland, for example). Because of this, as of the time of abstract submission, MAR is set up to run for a scenario with blowing snow as well as a scenario without blowing snow. Our final assessment will present the results of both, providing insight into the sensitivity of MAR outputs to the blowing snow model.

  12. Future climate and surface mass balance of Svalbard glaciers in an RCP8.5 climate scenario: a study with the regional climate model MAR forced by MIROC5

    Science.gov (United States)

    Lang, C.; Fettweis, X.; Erpicum, M.

    2015-05-01

    We have performed a future projection of the climate and surface mass balance (SMB) of Svalbard with the MAR (Modèle Atmosphérique Régional) regional climate model forced by MIROC5 (Model for Interdisciplinary Research on Climate), following the RCP8.5 scenario at a spatial resolution of 10 km. MAR predicts a similar evolution of increasing surface melt everywhere in Svalbard followed by a sudden acceleration of melt around 2050, with a larger melt increase in the south compared to the north of the archipelago. This melt acceleration around 2050 is mainly driven by the albedo-melt feedback associated with the expansion of the ablation/bare ice zone. This effect is dampened in part as the solar radiation itself is projected to decrease due to a cloudiness increase. The near-surface temperature is projected to increase more in winter than in summer as the temperature is already close to 0 °C in summer. The model also projects a stronger winter west-to-east temperature gradient, related to the large decrease of sea ice cover around Svalbard. By 2085, SMB is projected to become negative over all of Svalbard's glaciated regions, leading to the rapid degradation of the firn layer.

  13. Feasibility of Single and Dual Satellite Systems to Enable Continuous Communication Capability to a Manned Mars Mission

    Science.gov (United States)

    2014-09-01

    the layer or envelope of gases surrounding a planet (Merriam Webster, 2014). It is critical and largely causal to the morphology of a planet...Mars lasercom terminal. Retrieved IEEE Photonic Society from http://photonicssociety.org/ newsletters /oct05/lasercom.html Seahen. (n.d.). Conic

  14. Extended contingency table: Performance metrics for satellite observations and climate model simulations

    Science.gov (United States)

    AghaKouchak, A.; Mehran, A.

    2013-10-01

    Validation of gridded satellite observations and climate model simulations are fundamental to future improvements in retrieval algorithms and model developments. Among the metrics, the contingency table, which includes a number of categorical indices, is extensively used in evaluation studies. While the categorical indices offer invaluable information, they do not provide any insight into the volume of the variable detected correctly/incorrectly. In this study, the contingency table categorical metrics are extended to volumetric indices for evaluation of gridded data. The suggested indices include (a) Volumetric Hit Index (VHI): volume of correctly detected simulations relative to the volume of the correctly detected simulations and missed observations; (b) Volumetric False Alarm Ratio (VFAR): volume of false simulations relative to the sum of simulations; (c) Volumetric Miss Index (VMI): volume of missed observations relative to the sum of missed observations and correctly detected simulations; and (d) the Volumetric Critical Success Index (VCSI). The latter provides an overall measure of volumetric performance including volumetric hits, false alarms, and misses. First, using two synthetic time series, the volumetric indices are evaluated against the contingency table categorical metrics. Then, the volumetric indices are used to evaluate a gridded data set at the continental scale. The results show that the volumetric indices provide additional information beyond the commonly used categorical metrics that can be useful in evaluating gridded data sets.

  15. Prototype of the Mexican spatial data infrastructure for climate raster models and satellite imagery (“VISTA-C”)

    Science.gov (United States)

    Couturier, S.; Osorno Covarrubias, J.; Magaña Rueda, V.; Martínez Zazueta, I.; Vázquez Cruz, G.

    2017-01-01

    In the face of climatic uncertainty and its impacts on agriculture yields, there is a growing need for public institutions of subtropical countries to access as reliable as possible meteorological models and transmit a representation of their results in an effective way to stakeholders in agriculture. In many of these countries however, broad climatic regions and point-based statistics remain the core of these representations. The use of satellite imagery is largely limited to visual assessment, although it could serve as complementary data to meteorological raster models and the basis for spatially consistent quantitative impact assessments of meteorological events. In view of this situation in Mexico, a project developed by the Institute of Geography at UNAM university, and promoted by the National Institute of Geography and Statistics, consisted in the development of a climate monitoring system, which includes three main features: 1) a modular array storage system containing NOAA and GOES satellite imagery acquired though a receiving station (ERISA), 2) a climate modeling squeme based on successive error corrections of climate raster maps and associated models using the above mentioned imagery, and 3) an online, dynamic geovisualization of the results of the models. We discuss the implemented technologies and illustrate the VISTA-C prototype which has been released.

  16. Duration and rapid shutdown of Mars lake-forming climates explained by methane bursts

    CERN Document Server

    Kite, Edwin S; Gao, Peter; Mayer, David P

    2016-01-01

    Build-up of relatively young ($$3 Kyr (assuming dilute flow), but the watersheds' little-weathered soils indicate a climate history that was $>$99% dry. The lake-forming climates' trigger mechanism remains unknown. Here we show that these intermittency constraints, while inconsistent with many previously-proposed triggers for lake-forming climates, are consistent with a novel CH$_4$-burst mechanism. Chaotic transitions in mean obliquity drive latitudinal shifts in temperature and ice loading that destabilize CH$_4$ clathrate. For past clathrate hydrate stability zone occupancy fractions $>\\sim$0.2, we show that CH$_4$($\\pm$C$_2$H$_6$) builds up to levels whose radiative forcing ($>$15 W/m$^2$, plus feedbacks) is sufficient to modulate lake-forming climates. Such occupancy fractions are consistent with CH$_4$+C$_2$H$_6$ production by $>$3 Ga water-rock reactions. Sub-lake CH$_4$ destabilization provides positive feedback. UV-limited CH$_4$ photolysis curtails individual lake-forming climates to $<$10$^6$ yr...

  17. Updates on Modeling the Water Cycle with the NASA Ames Mars Global Climate Model

    Science.gov (United States)

    Kahre, M. A.; Haberle, R. M.; Hollingsworth, J. L.; Montmessin, F.; Brecht, A. S.; Urata, R.; Klassen, D. R.; Wolff, M. J.

    2017-01-01

    Global Circulation Models (GCMs) have made steady progress in simulating the current Mars water cycle. It is now widely recognized that clouds are a critical component that can significantly affect the nature of the simulated water cycle. Two processes in particular are key to implementing clouds in a GCM: the microphysical processes of formation and dissipation, and their radiative effects on heating/ cooling rates. Together, these processes alter the thermal structure, change the dynamics, and regulate inter-hemispheric transport. We have made considerable progress representing these processes in the NASA Ames GCM, particularly in the presence of radiatively active water ice clouds. We present the current state of our group's water cycle modeling efforts, show results from selected simulations, highlight some of the issues, and discuss avenues for further investigation.­

  18. Tracking Climate Effects on Plant-Pollinator Interaction Phenology with Satellites and Honey Bee Hives

    Science.gov (United States)

    Esaias, Wayne E.; Nickeson, Jaime E.; Tan, Bin; Ma, Peter L.; Nightingale, Joanne M.; Wolfe, Robert E.

    2011-01-01

    Background/Question/Methods: The complexity of plant-pollinator interactions, the large number of species involved, and the lack of species response functions present challenges to understanding how these critical interactions may be impacted by climate and land cover change on large scales. Given the importance of this interaction for terrestrial ecosystems, it is desirable to develop new approaches. We monitor the daily weight change of honey bee (Apis mellifera) colonies to record the phenology of the Honey Bee Nectar Flow (HBNF) in a volunteer network (honeybeenet.gsfc.nasa.gov). The records document the successful interaction of a generalist pollinator with a variety of plant resources. We extract useful HBNF phenology metrics for three seasons. Sites currently exist in 35 states/provinces in North America, with a concentration in the Mid-Atlantic region. HBNF metrics are compared to standard phenology metrics derived from remotely sensed vegetation indices from NASA's MODIS sensor and published results from NOAA's A VHRR. At any given time the percentage of plants producing nectar is usually a sma11 fraction of the total satellite sensor signal. We are interested in determining how well the 'bulk' satellite vegetation parameters relate to the phenology of the HBNF, and how it varies spatially on landscape to continental scales. Results/Conclusions: We found the median and peak seasonal HBNF dates to be robust, with variation between replicate scale hives of only a few days. We developed quality assessment protocols to identify abnormal colony artifacts. Temporally, the peak and median of the HBNF in the Mid-Atlantic show a significant advance of 0.58 d/y beginning about 1970, very similar to that observed by the A VHRR since 1982 (0.57 d/y). Spatially, the HBNF metrics are highly correlated with elevation and winter minimum temperature distribution, and exhibit significant but regionally coherent inter-annual variation. The relationship between median of the

  19. The impact of orbital sampling, monthly averaging and vertical resolution on climate chemistry model evaluation with satellite observations

    Directory of Open Access Journals (Sweden)

    A. M. Aghedo

    2011-07-01

    Full Text Available Ensemble climate model simulations used for the Intergovernmental Panel on Climate Change (IPCC assessments have become important tools for exploring the response of the Earth System to changes in anthropogenic and natural forcings. The systematic evaluation of these models through global satellite observations is a critical step in assessing the uncertainty of climate change projections. This paper presents the technical steps required for using nadir sun-synchronous infrared satellite observations for multi-model evaluation and the uncertainties associated with each step. This is motivated by need to use satellite observations to evaluate climate models. We quantified the implications of the effect of satellite orbit and spatial coverage, the effect of variations in vertical sensitivity as quantified by the observation operator and the impact of averaging the operators for use with monthly-mean model output. We calculated these biases in ozone, carbon monoxide, atmospheric temperature and water vapour by using the output from two global chemistry climate models (ECHAM5-MOZ and GISS-PUCCINI and the observations from the Tropospheric Emission Spectrometer (TES instrument on board the NASA-Aura satellite from January 2005 to December 2008.

    The results show that sampling and monthly averaging of the observation operators produce zonal-mean biases of less than ±3 % for ozone and carbon monoxide throughout the entire troposphere in both models. Water vapour sampling zonal-mean biases were also within the insignificant range of ±3 % (that is ±0.14 g kg−1 in both models. Sampling led to a temperature zonal-mean bias of ±0.3 K over the tropical and mid-latitudes in both models, and up to −1.4 K over the boundary layer in the higher latitudes. Using the monthly average of temperature and water vapour operators lead to large biases over the boundary layer in the southern-hemispheric higher latitudes and in the upper

  20. The impact of orbital sampling, monthly averaging and vertical resolution on climate chemistry model evaluation with satellite observations

    Directory of Open Access Journals (Sweden)

    A. M. Aghedo

    2011-03-01

    Full Text Available Ensemble climate model simulations used for the Intergovernmental Panel on Climate Change (IPCC assessments have become important tools for exploring the response of the Earth System to changes in anthropogenic and natural forcings. The systematic evaluation of these models through global satellite observations is a critical step in assessing the uncertainty of climate change projections. This paper presents the technical steps required for using nadir sun-synchronous infrared satellite observations for multi-model evaluation and the uncertainties associated with each step. This is motivated by need to use satellite observations to evaluate climate models. We quantified the implications of the effect of satellite orbit and spatial coverage, the effect of variations in vertical sensitivity as quantified by the observation operator and the impact of averaging the operators for use with monthly-mean model output. We calculated these biases in ozone, carbon monoxide, atmospheric temperature and water vapour by using the output from two global chemistry climate models (ECHAM5-MOZ and GISS-PUCCINI and the observations from the Tropospheric Emission Spectrometer (TES satellite from January 2005 to December 2008.

    The results show that sampling and monthly averaging of the observation operators produce biases of less than ±3% for ozone and carbon monoxide throughout the entire troposphere in both models. Water vapour sampling biases were also within the insignificant range of ±3% (that is ±0.14 g kg−1 in both models. Sampling led to a temperature bias of ±0.3 K over the tropical and mid-latitudes in both models, and up to −1.4 K over the boundary layer in the higher latitudes. Using the monthly average of temperature and water vapour operators lead to large biases over the boundary layer in the southern-hemispheric higher latitudes and in the upper troposphere, respectively. Up to 8% bias was calculated in the upper

  1. Management and climate contributions to satellite-derived active fire trends in the contiguous United States

    Science.gov (United States)

    Lin, Hsiao-Wen; McCarty, Jessica L.; Wang, Dongdong; Rogers, Brendan M.; Morton, Douglas C.; Collatz, G. James; Jin, Yufang; Randerson, James T.

    2014-04-01

    Fires in croplands, plantations, and rangelands contribute significantly to fire emissions in the United States, yet are often overshadowed by wildland fires in efforts to develop inventories or estimate responses to climate change. Here we quantified decadal trends, interannual variability, and seasonality of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) observations of active fires (thermal anomalies) as a function of management type in the contiguous U.S. during 2001-2010. We used the Monitoring Trends in Burn Severity database to identify active fires within the perimeter of large wildland fires and land cover maps to identify active fires in croplands. A third class of fires defined as prescribed/other included all residual satellite active fire detections. Large wildland fires were the most variable of all three fire types and had no significant annual trend in the contiguous U.S. during 2001-2010. Active fires in croplands, in contrast, increased at a rate of 3.4% per year. Cropland and prescribed/other fire types combined were responsible for 77% of the total active fire detections within the U.S and were most abundant in the south and southeast. In the west, cropland active fires decreased at a rate of 5.9% per year, likely in response to intensive air quality policies. Potential evaporation was a dominant regulator of the interannual variability of large wildland fires, but had a weaker influence on the other two fire types. Our analysis suggests it may be possible to modify landscape fire emissions within the U.S. by influencing the way fires are used in managed ecosystems.

  2. The poles of Mars, past and present: A high-resolution observational study of the martian polar regions and their connection to climate

    Science.gov (United States)

    Becerra, Patricio

    The poles of Mars, much like Earth's polar regions, are covered by kilometer-thick sheets of ice that interact with the Martian atmosphere and can record climatic changes in their stratigraphy. These polar caps are composed of several icy sections that interact with the Martian environment over different timescales. This dissertation describes my investigation of two of these units: The South Polar Residual Cap (SPRC), and the North Polar Layered Deposits (NPLD). The overarching theme of my work is to explore the connections between these caps and the current (SPRC) and past (NPLD) climate of Mars using a wide variety of data from spacecraft missions, and applying numerical models of surface properties and processes to interpret the observations. (Abstract shortened by ProQuest.).

  3. Satellite-Based Thermophysical Analysis of Volcaniclastic Deposits: A Terrestrial Analog for Mantled Lava Flows on Mars

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    Mark A. Price

    2016-02-01

    Full Text Available Orbital thermal infrared (TIR remote sensing is an important tool for characterizing geologic surfaces on Earth and Mars. However, deposition of material from volcanic or eolian activity results in bedrock surfaces becoming significantly mantled over time, hindering the accuracy of TIR compositional analysis. Moreover, interplay between particle size, albedo, composition and surface roughness add complexity to these interpretations. Apparent Thermal Inertia (ATI is the measure of the resistance to temperature change and has been used to determine parameters such as grain/block size, density/mantling, and the presence of subsurface soil moisture/ice. Our objective is to document the quantitative relationship between ATI derived from orbital visible/near infrared (VNIR and thermal infrared (TIR data and tephra fall mantling of the Mono Craters and Domes (MCD in California, which were chosen as an analog for partially mantled flows observed at Arsia Mons volcano on Mars. The ATI data were created from two images collected ~12 h apart by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER instrument. The results were validated with a quantitative framework developed using fieldwork that was conducted at 13 pre-chosen sites. These sites ranged in grain size from ash-sized to meter-scale blocks and were all rhyolitic in composition. Block size and mantling were directly correlated with ATI. Areas with ATI under 2.3 × 10−2 were well-mantled with average grain size below 4 cm; whereas values greater than 3.0 × 10−2 corresponded to mantle-free surfaces. Correlation was less accurate where checkerboard-style mixing between mantled and non-mantled surfaces occurred below the pixel scale as well as in locations where strong shadowing occurred. However, the results validate that the approach is viable for a large majority of mantled surfaces on Earth and Mars. This is relevant for determining the volcanic history of Mars, for

  4. A stable, unbiased, long-term satellite based data record of sea surface temperature from ESA's Climate Change Initiative

    Science.gov (United States)

    Rayner, Nick; Good, Simon; Merchant, Chris

    2013-04-01

    The study of climate change demands long-term, stable observational records of climate variables such as sea surface temperature (SST). ESA's Climate Change Initiative was set up to unlock the potential of satellite data records for this purpose. As part of this initiative, 13 projects were established to develop the data records for different essential climate variables - aerosol, cloud, fire, greenhouse gases, glaciers, ice sheets, land cover, ocean colour, ozone, sea ice, sea level, soil moisture and SST. In this presentation we describe the development work that has taken place in the SST project and present new prototype data products that are available now for users to trial. The SST project began in 2010 and has now produced two prototype products. The first is a long-term product (covering mid-1991 - 2010 currently, but with a view to update this in the future), which prioritises length of data record and stability over other considerations. It is based on data from the Along-Track Scanning Radiometer (ATSR) and Advanced Very-High Resolution Radiometer (AVHRR) series of satellite instruments. The product aims to combine the favourable stability and bias characteristics of ATSR data with the geographical coverage achieved with the AVHRR series. Following an algorithm selection process, an optimal estimation approach to retrieving SST from the satellite measurements from both sensors was adopted. The retrievals do not depend on in situ data and so this data record represents an independent assessment of SST change. In situ data are, however, being used to validate the resulting data. The second data product demonstrates the coverage that can be achieved using the modern satellite observing system including, for example, geostationary satellite data. Six months worth of data have been processed for this demonstration product. The prototype SST products will be released in April to users to trial in their work. The long term product will be available as

  5. Geology and Mineralogy of Ancient Sea Deposits in Eridania Basin, Mars: Implications for Noachian Climate

    Science.gov (United States)

    Michalski, J. R.; Noe Dobrea, E. Z.; Cuadros, J.; Niles, P. B.

    2016-12-01

    At the same time when life appeared in seafloor deposits on Earth (>3.8 billion years ago), the Eridania basin on Mars was the site of a vast (>106 km2), deep (>1 km) inland sea. Though the Eridania basin has been eroded and largely resurfaced by subsequent volcanism, deep basin seafloor deposits are recognizable. Thick (>500 m) deposits found in the deepest parts of the basin - the oldest observable basin deposits - contain no evidence of bedding at the scale of meters-decameters, but display mottled colour patterns and contain pervasive irregular and boxwork veins. We show that the most ancient subaqueous basin deposits correspond to saponite, talc-saponite, Fe-rich mica (e.g. glauconite-nontronite), Fe- and Mg-serpentine, and Mg-Fe-Ca-carbonate that likely formed in a hydrothermal seafloor setting. Jarosite within the same unit likely indicates that sulphides were present in the deep-water deposits, but have been weathered upon exposure at the surface. While thin deposits of chloride salts at high elevations near the interior basin margins are indicative of evaporite deposits in shallow water, the deep water mineral assemblages cannot be explained by an evaporite-playa setting. The thick, deep basin deposits in Eridania formed in deep water, likely in a hydrothermal seafloor setting. The Eridania sea likely persisted over a geologically significant period of time in the Late Noachian. Abundant Fe present in the seafloor deposits likely indicates reducing conditions, which could have formed in a stratified sea in contact with an oxidizing atmosphere, a reduced sea beneath a reduced atmosphere, or an ice-covered sea.

  6. Redefining climate regions in the United States of America using satellite remote sensing and machine learning for public health applications

    Directory of Open Access Journals (Sweden)

    Alexander Liss

    2014-12-01

    Full Text Available Existing climate classification has not been designed for an efficient handling of public health scenarios. This work aims to design an objective spatial climate regionalization method for assessing health risks in response to extreme weather. Specific climate regions for the conterminous United States of America (USA were defined using satellite remote sensing (RS data and compared with the conventional Köppen-Geiger (KG divisions. Using the nationwide database of hospitalisations among the elderly (≥65 year olds, we examined the utility of a RS-based climate regionalization to assess public health risk due to extreme weather, by comparing the rate of hospitalisations in response to thermal extremes across climatic regions. Satellite image composites from 2002-2012 were aggregated, masked and compiled into a multi-dimensional dataset. The conterminous USA was classified into 8 distinct regions using a stepwise regionalization approach to limit noise and collinearity (LKN, which exhibited a high degree of consistency with the KG regions and a well-defined regional delineation by annual and seasonal temperature and precipitation values. The most populous was a temperate wet region (10.9 million, while the highest rate of hospitalisations due to exposure to heat and cold (9.6 and 17.7 cases per 100,000 persons at risk, respectively was observed in the relatively warm and humid south-eastern region. RS-based regionalization demonstrates strong potential for assessing the adverse effects of severe weather on human health and for decision support. Its utility in forecasting and mitigating these effects has to be further explored.

  7. Preface to the Special Issue on "Geophysical and Climate Change Studies in Tibet, Xinjiang, and Siberia (TibXS from Satellite Geodesy"

    Directory of Open Access Journals (Sweden)

    Cheinway Hwang

    2013-01-01

    Full Text Available This special issue publishes papers on recent results in geophysical and climate change studies over Tibet, Xinjiang and Siberia (TibXS based upon some of the key sensors used in satellite geodesy, including satellite gravimetric sensors (GRACE and GOCE, satellite altimeters (TOPEX, Jason-1 and -2, and ENVISAT, and Global Positioning System satellites. Results from ground- and airborne-based geodetic observations, notably those based on airborne gravimeter, superconducting gravimeter (SG and seismometers are also included in the special issue. In all, 22 papers were submitted for this special issue; 17 papers were accepted.

  8. Lightning hazard region over the maritime continent observed from satellite and climate change threat

    Science.gov (United States)

    Ilhamsyah, Y.; Koesmaryono, Y.; Hidayat, R.; Murjaya, J.; Nurjaya, I. W.; Rizwan

    2017-02-01

    Climate change would lead to such hydrometeorological disaster as: flash-flood, landslide, hailstone, lightning, and twister become more likely to happen in the future. In terms of lightning event, one research question arise of where lightning would be mostly to strike over the Maritime Continent (MC)?. The objective of the research is to investigate region with high-density of lightning activity over MC by mapping climatological features of lightning flashes derived from onboard NASA-TRMM Satellite, i.e. Optical Transient Detector/Lightning Imaging Sensor (OTD/LIS). Based on data retrieved since 1995-2013, it is seasonally observed that during transition season March to May, region with high vulnerability of lightning flashes cover the entire Sumatra Island, the Malacca Strait, and Peninsular Malaysia as well as Java Island. High-frequent of lightning activity over the Malacca Strait is unique since it is the only sea-region in the world where lightning flashes are denser. As previously mentioned that strong lightning activity over the strait is driven by mesoscale convective system of Sumatra Squalls due to convergences of land breeze between Sumatra and Peninsular Malaysia. Lightning activity over the strait is continuously observed throughout season despite the intensity reduced. Java Island, most populated island, receive high-density of lightning flashes during rainy season (December to February) but small part in the northwestern of Java Island, e.g., Bogor and surrounding areas, the density of lightning flashes are high throughout season. Northern and southern parts of Kalimantan and Central part of Sulawesi are also prone to lightning activity particularly during transition season March to May and September to November. In the eastern part of MC, Papua receive denser lightning flashes during September to November. It is found that lightning activity are mostly concentrated over land instead of ocean which is in accordance with diurnal convective

  9. Synergy use of satellite remote sensing and in-situ monitoring data for air pollution impacts on urban climate

    Science.gov (United States)

    Savastru, Dan M.; Zoran, Maria A.; Savastru, Roxana S.

    2016-10-01

    The increase of urban atmospheric pollution due to particulate matters (PM) in different fraction sizes affects seriously not only human health and environment, but also city climate directly and indirectly. In the last decades, with the economic development and the increased emissions from industrial, traffic and domestic pollutants, the urban atmospheric pollution with remarkable high PM2.5 (particulate matters with aerodynamic diameter less than 2.5 μm) and PM10 (particulate matters with aerodynamic diameter less than 10 μm) concentration levels became serious in the metropolitan area of Bucharest in Romania. Both active as well as satellite remote sensing are key applications in global change science and urban climatology. The aerosol parameters can be measured directly in situ or derived from satellite remote sensing observations. All these methods are important and complementary. The current study presents a spatiotemporal analysis of the aerosol concentrations in relation with climate parameters in two size fractions (PM10 and PM2.5) in Bucharest metropolitan area. Daily average particle matters concentrations PM10 and PM2.5 for Bucharest metropolitan area have been provided by 8 monitoring stations belonging to air pollution network of Environmental Protection Agency. The C005 (version 5.1) Level 2 and Level 3 Terra and Aqua MODIS AOD550 time-series satellite data for period 01/01/2011- 31/12/2012 have been also used. Meteorological variables (air temperature, relative humidity, sea level atmospheric pressure) have been provided by in-situ measurements. Both in-situ monitoring data as well as MODIS Terra/Aqua time-series satellite data for 2011-2012 period provided useful tools for particle matter PM2.5 and PM10 monitoring.

  10. Mars Atmospheric CO2 Condensation Above the North and South Poles as Revealed by Radio Occultation, Climate Sounder, and Laser Ranging Observations

    Science.gov (United States)

    Hu, Renyu; Cahoy, Kerri; Zuber, Maria T.

    2012-01-01

    We study the condensation of CO2 in Mars atmosphere using temperature profilesretrieved from radio occultation measurements from Mars Global Surveyor (MGS) as wellas the climate sounding instrument onboard the Mars Reconnaissance Orbiter (MRO),and detection of reflective clouds by the MGS Mars Orbiter Laser Altimeter (MOLA). Wefind 11 events in 1999 where MGS temperature profiles indicate CO2 condensation andMOLA simultaneously detects reflective clouds. We thus provide causal evidence thatMOLA non-ground returns are associated with CO2 condensation, which strongly indicatestheir nature being CO2 clouds. The MGS and MRO temperature profiles together revealthe seasonal expansion and shrinking of the area and the vertical extent of atmosphericsaturation. The occurrence rate of atmospheric saturation is maximized at high latitudes inthe middle of winter. The atmospheric saturation in the northern polar region exhibits moreintense seasonal variation than in the southern polar region. In particular, a shrinking ofsaturation area and thickness from LS 270 to 300 in 2007 is found; this is probablyrelated to a planet-encircling dust storm. Furthermore, we integrate the condensation areaand the condensation occurrence rate to estimate cumulative masses of CO2 condensatesdeposited onto the northern and southern seasonal polar caps. The precipitation flux isapproximated by the particle settling flux which is estimated using the impulse responses ofMOLA filter channels. With our approach, the total atmospheric condensation mass canbe estimated from these observational data sets with average particle size as the onlyfree parameter. By comparison with the seasonal polar cap masses inferred from thetime-varying gravity of Mars, our estimates indicate that the average condensate particleradius is 822 mm in the northern hemisphere and 413 mm in the southern hemisphere.Our multi-instrument data analysis provides new constraints on modeling the global climateof Mars.

  11. A Satellite-Based Surface Radiation Climatology Derived by Combining Climate Data Records and Near-Real-Time Data

    Directory of Open Access Journals (Sweden)

    Bodo Ahrens

    2013-09-01

    Full Text Available This study presents a method for adjusting long-term climate data records (CDRs for the integrated use with near-real-time data using the example of surface incoming solar irradiance (SIS. Recently, a 23-year long (1983–2005 continuous SIS CDR has been generated based on the visible channel (0.45–1 μm of the MVIRI radiometers onboard the geostationary Meteosat First Generation Platform. The CDR is available from the EUMETSAT Satellite Application Facility on Climate Monitoring (CM SAF. Here, it is assessed whether a homogeneous extension of the SIS CDR to the present is possible with operationally generated surface radiation data provided by CM SAF using the SEVIRI and GERB instruments onboard the Meteosat Second Generation satellites. Three extended CM SAF SIS CDR versions consisting of MVIRI-derived SIS (1983–2005 and three different SIS products derived from the SEVIRI and GERB instruments onboard the MSG satellites (2006 onwards were tested. A procedure to detect shift inhomogeneities in the extended data record (1983–present was applied that combines the Standard Normal Homogeneity Test (SNHT and a penalized maximal T-test with visual inspection. Shift detection was done by comparing the SIS time series with the ground stations mean, in accordance with statistical significance. Several stations of the Baseline Surface Radiation Network (BSRN and about 50 stations of the Global Energy Balance Archive (GEBA over Europe were used as the ground-based reference. The analysis indicates several breaks in the data record between 1987 and 1994 probably due to artefacts in the raw data and instrument failures. After 2005 the MVIRI radiometer was replaced by the narrow-band SEVIRI and the broadband GERB radiometers and a new retrieval algorithm was applied. This induces significant challenges for the homogenisation across the satellite generations. Homogenisation is performed by applying a mean-shift correction depending on the shift size of

  12. Constructing new satellite-only time series of global mean, sea surface temperature data for climate from ATSR data

    Science.gov (United States)

    Veal, Karen; Remedios, John; Ghent, Darren

    2013-04-01

    The Along Track Scanning Radiometers (ATSRs) have provided a near-continuous record of sea surface temperature (SST) data for climate from the launch of ATSR-1 in 1991 to the loss of the Advanced ATSR (AATSR) in April 2012. The intention was always to provide an SST record, independent of in situ data, to corroborate and improve climate data records in recent times. We show that the ATSR record provides a very suitable data set with which to study the recent climate record, particularly during the ATSR-2 and AATSR periods (1995 to 2012) in three major respects. First, ATSR climate time series achieve anomaly accuracies of better than 0.05 K (and high stability). Second, the overlap between instruments allows for excellent determination and removal of biases; between ATSR-2 and AATSR, these are less than 0.05 K for the highest accuracy SST data. Finally, uncertainties on global monthly mean data are less than 0.02 K and hence comparable to those achieved by in situ analyses such as HadSST3. A particular hallmark of the ATSR instruments was their exceptional design for accuracy incorporating high accuracy radiometric calibration, dual-view of the Earth's surface and the use of three thermal emission channels; additional channels are included for cloud clearing in this context. The use of dual-view and multiple thermnal wavelengths allows a number of combinations for retrievals of SST, the most accurate being the dual-view, three-channel retrieval (D3) at nighttime. This restriction is due to the use of the 3.7 micron channel which is sensitive to solar radiation during the day. Extensive work has resulted in a major advances recently resulting in both an operational V2.0 SST product and a further improved ATSR Re-analysis for Climate (ARC) product, a particular feature of the latter being the development of a depth SST product in addition to the skin SST directly determined from satellite data. We will discuss the characteristics of these data sets in terms of

  13. Satellite Remote Sensing Missions for Monitoring Water, Carbon, and global Climate Change

    Science.gov (United States)

    In recent years, the subjects of water, carbon, and global climate change have attracted worldwide attention by scientists and the media. Climate change, whether associated with human- induced or natural variations, has and will continue to be important to policy makers and the public. It is clear t...

  14. Improved sea level record over the satellite altimetry era (1993–2010 from the Climate Change Initiative Project

    Directory of Open Access Journals (Sweden)

    M. Ablain

    2014-08-01

    Full Text Available Sea level is one of the 50 Essential Climate Variables (ECVs listed by the Global Climate Observing System (GCOS in climate change monitoring. In the last two decades, sea level has been routinely measured from space using satellite altimetry techniques. In order to address a number of important scientific questions such as: "Is sea level rise accelerating?", "Can we close the sea level budget?", "What are the causes of the regional and interannual variability?", "Can we already detect the anthropogenic forcing signature and separate it from the internal/natural climate variability?", and "What are the coastal impacts of sea level rise?", the accuracy of altimetry-based sea level records at global and regional scales needs to be significantly improved. For example, the global mean and regional sea level trend uncertainty should become better than 0.3 and 0.5 mm year−1, respectively (currently of 0.6 and 1–2 mm year−1. Similarly, interannual global mean sea level variations (currently uncertain to 2–3 mm need to be monitored with better accuracy. In this paper, we present various respective data improvements achieved within the European Space Agency (ESA Climate Change Initiative (ESA CCI project on "Sea Level" during its first phase (2010–2013, using multi-mission satellite altimetry data over the 1993–2010 time span. In a first step, using a new processing system with dedicated algorithms and adapted data processing strategies, an improved set of sea level products has been produced. The main improvements include: reduction of orbit errors and wet/dry atmospheric correction errors, reduction of instrumental drifts and bias, inter-calibration biases, intercalibration between missions and combination of the different sea level data sets, and an improvement of the reference mean sea surface. We also present preliminary independent validations of the SL_cci products, based on tide gauges comparison and sea level budget closure approach

  15. Salt or ice diapirism origin for the honeycomb terrain in Hellas basin, Mars?: Implications for the early martian climate

    Science.gov (United States)

    Weiss, David K.; Head, James W.

    2017-03-01

    The "honeycomb" terrain is a Noachian-aged cluster of ∼7 km wide linear cell-like depressions located on the northwestern floor of Hellas basin, Mars. A variety of origins have been proposed for the honeycomb terrain, including deformation rings of subglacial sediment, frozen convection cells from a Hellas impact melt sheet, a swarm of igneous batholiths, salt diapirism, and ice diapirism. Recent work has shown that the salt or ice diapirism scenarios appear to be most consistent with the morphology and morphometry of the honeycomb terrain. The salt and ice diapirism scenarios have different implications for the ancient martian climate and hydrological cycle, and so distinguishing between the two scenarios is critical. In this study, we specifically test whether the honeycomb terrain is consistent with a salt or ice diapir origin. We use thermal modeling to assess the stability limits on the thickness of an ice or salt diapir-forming layer at depth within the Hellas basin. We also apply analytical models for diapir formation to evaluate the predicted diapir wavelengths in order to compare with observations. Ice diapirism is generally predicted to reproduce the observed honeycomb wavelengths for ∼100 m to ∼1 km thick ice deposits. Gypsum and kieserite diapirism is generally predicted to reproduce the observed honeycomb wavelengths for ≥ 600-1000 m thick salt deposits, but only with a basaltic overburden. Halite diapirism generally requires approx. ≥ 1 km thick halite deposits in order to reproduce the observed honeycomb wavelengths. Hellas basin is a distinctive environment for diapirism on Mars due to its thin crust (which reduces surface heat flux), low elevation (which allows Hellas to act as a water/ice/sediment sink and increases the surface temperature), and location within the southern highlands (which may provide proximity to inflowing saline water or glacial ice). The plausibility of an ice diapir mechanism generally requires temperatures ≤ 250

  16. Monitoring global climate change using SLR data from LARES and other geodetic satellites

    Science.gov (United States)

    Paolozzi, Antonio; Paris, Claudio; Pavlis, Erricos C.; Sindoni, Giampiero; Ciufolini, Ignazio

    2016-04-01

    The Earth Orientation Parameters (EOP), i.e. the spin axis of the Earth, is influenced by the mass redistribution inside and on the surface of the Earth. On the Earth surface, global ice melting, sea level change and atmospheric circulation are the prime contributors. Recent studies have unraveled the majority of the mysteries behind the Chandler wobble, the annual motion and the secular motion of the pole. The differences from the motion of a pole for a rigid Earth is indeed due to the mass redistribution and transfer of angular momentum among the atmosphere, the oceans and solid Earth. The technique of laser ranging and the use of laser ranged satellites such as LARES along with other techniques such Very Long Baseline Interferometry (VLBI) allow to measure the EOP with accuracies at the level of ~200 μas which correspond to few millimeters at the Earth's surface, while the use of Global Navigation Satellite System (GNSS) data can reach an accuracy even below 100 μas. At these unprecedented high levels of accuracy, even tiny anomalous behavior in EOP can be observed and thus correlated to global environmental changes such as ice melting on Greenland and the polar caps, and extreme events that involve strong ocean-atmosphere coupling interactions such as the El Niño. The contribution of Satellite Laser Ranging (SLR) data such as from the LARES mission and similar satellites to this area is outlined in this paper.

  17. Satellite monitoring the rangeland degradation under the impacts of climatic and socio-economic changes over central Asia

    Science.gov (United States)

    Wang, K.; Zhang, L.; Dai, L.; Yan, D.

    2012-12-01

    Central Asia, encompassing the republics of Kazakhstan, Kyrgyz, Uzbekistan, Turkmenistan, Tajikistan and China's western Sinkiang, is a typical arid and semi-arid area. The climate in Central Asia is extreme arid, where summer is hot, cloudless and dry, and winter is moist and relatively warm in the south and cold and dry in the north. Rangeland, accounting for 46% of the entire area, is the main vegetation type in this area. Recent findings showed that climate change had caused unprecedented rangeland degradation in Central Asia over the past 30 years. Socio-economical change and environmental change due to the collapse of Soviet Union also accelerated rangeland degradation. Rangeland degradation adversely further deteriorated the environment. With the development of high resolution remote sensing images, an increasing attention has paid to study rangeland degradation in this area. However, previous investigations based on either Advanced Very High Resolution Radiometer (AVHRR) or Moderate Resolution Imaging Spectroradiometer (MODIS) data, has not integrate multi-resolution satellite data for investigating vegetation change and its response to climatic and socio-economic change . In this paper, we employed 30 years' remote sensing data, including both AVHRR ( 1982-2006) and MODIS (2000-2011) satellite data, and in-situ meteorological and social data (e.g. population, economic, and land use change data), to investigate rangeland degradation in the central Asia. We 1) analyzed the spatial-temporal variations of vegetation changes during the past 30 years, and 2) evaluated the roles of climatic and socio-economic factors as potential causes of observed vegetation changes. The results showed extensive area had statistically significant degradation trends (p<0.05). Precipitation was the main driver of rangeland degradation, while there were relatively weaker relationships between temperature and NDVI, indicating that water deficit largely limited vegetation activity

  18. Identifying Local Scale Climate Zones of Urban Heat Island from HJ-1B Satellite Data Using Self-Organizing Maps

    Science.gov (United States)

    Wei, C. Z.; Blaschke, T.

    2016-10-01

    With the increasing acceleration of urbanization, the degeneration of the environment and the Urban Heat Island (UHI) has attracted more and more attention. Quantitative delineation of UHI has become crucial for a better understanding of the interregional interaction between urbanization processes and the urban environment system. First of all, our study used medium resolution Chinese satellite data-HJ-1B as the Earth Observation data source to derive parameters, including the percentage of Impervious Surface Areas, Land Surface Temperature, Land Surface Albedo, Normalized Differential Vegetation Index, and object edge detector indicators (Mean of Inner Border, Mean of Outer border) in the city of Guangzhou, China. Secondly, in order to establish a model to delineate the local climate zones of UHI, we used the Principal Component Analysis to explore the correlations between all these parameters, and estimate their contributions to the principal components of UHI zones. Finally, depending on the results of the PCA, we chose the most suitable parameters to classify the urban climate zones based on a Self-Organization Map (SOM). The results show that all six parameters are closely correlated with each other and have a high percentage of cumulative (95%) in the first two principal components. Therefore, the SOM algorithm automatically categorized the city of Guangzhou into five classes of UHI zones using these six spectral, structural and climate parameters as inputs. UHI zones have distinguishable physical characteristics, and could potentially help to provide the basis and decision support for further sustainable urban planning.

  19. Recent climate cycles on Mars: Stratigraphic relationships between multiple generations of gullies and the latitude dependent mantle

    Science.gov (United States)

    Dickson, James L.; Head, James W.; Goudge, Timothy A.; Barbieri, Lindsay

    2015-05-01

    Reconstructions of the orbital parameters of Mars spanning the last ∼20 Myr, combined with global circulation models, predict multiple cycles of accumulation and degradation of an ice-rich mantle in the mid-latitudes, driven primarily by insolation at the poles during periods when obliquity was more than ten degrees greater than it is today (i.e., >∼35°). While evidence of an ice-rich "latitude dependent mantle" (LDM) consistent with these predictions is abundant, features indicative of cycles of emplacement and degradation of this unit are isolated and rare. In addition, fundamental physical properties of the LDM, such as paleo-thickness maxima, have not been determined. Gullies, which are sinuous channels found on steep slopes in mid- and high-latitudes, interact with the LDM and provide a stratigraphic feature useful for documenting both cyclical emplacement/removal and thickness estimates in past climate regimes. In the southern hemisphere, where gullies are most common, we present extensive evidence of (1) cyclical degradation and removal of gullies in the lower mid-latitudes (30-40°S), and (2) burial and exhumation of inverted gully channels in the transitional latitude band between dissected and preserved LDM (40-50°S), which can only be accounted for if an additional tens of meters of LDM were present at these locations during channel formation. These relationships support a model in which end-to-end gully evolution is controlled by the behavior of the LDM: at lower latitudes, gullies incise an ice-rich substrate and are removed when that ice becomes unstable, and at higher latitudes gullies are buried by successive emplacement of LDM where ice remains stable near the surface. Further, the presence of dormant buried gullies implies that present-day activity within gullies, likely to be controlled by the behavior of CO2 frost, is insufficient to explain the entire gully population, and that conditions conducive to increased gully activity preceded the

  20. Remote Sensing of Aerosols from Satellites: Why Has It Been Do Difficult to Quantify Aerosol-Cloud Interactions for Climate Assessment, and How Can We Make Progress?

    Science.gov (United States)

    Kahn, Ralph A.

    2015-01-01

    The organizers of the National Academy of Sciences Arthur M. Sackler Colloquia Series on Improving Our Fundamental Understanding of the Role of Aerosol-Cloud Interactions in the Climate System would like to post Ralph Kahn's presentation entitled Remote Sensing of Aerosols from Satellites: Why has it been so difficult to quantify aerosol-cloud interactions for climate assessment, and how can we make progress? to their public website.

  1. Satellite theory

    Science.gov (United States)

    Kozai, Y.

    1981-04-01

    The dynamical characteristics of the natural satellite of Mars, Jupiter, Saturn, Uranus and Neptune are analyzed on the basis of the solar tidal perturbation factor and the oblateness factor of the primary planet for each satellite. For the inner satellites, for which the value of the solar tidal factor is much smaller than the planetary oblateness factor, it is shown that the eccentricity and inclination of satellite orbits are generally very small and almost constant; several pairs of inner satellites are also found to exhibit commensurable mean motions, or secular accelerations in mean longitude. In the case of the outer satellites, for which solar perturbations are dominant, secular perturbations and long-period perturbations may be derived by the solution of equations of motion reduced to one degree of freedom. The existence of a few satellites, termed intermediary satellites, for which the solar tidal perturbation is on the order of the planetary oblateness factor, is also observed, and the pole of the orbital plane of the satellite is noted to execute a complex motion around the pole of the planet or the orbital plane of the planet.

  2. Variability of the thermospheric temperatures of Mars during 9 Martian Years as given by a ground-to-exosphere Global Climate Model

    Science.gov (United States)

    Gonzalez-Galindo, Francisco; Forget, Francois; Garcia-Comas, Maya; Millour, Ehouarn; Lopez-Valverde, Miguel; Montabone, Luca

    2016-07-01

    The temperature of the Martian upper thermosphere is one of the main factors affecting the rate of the different escape to space processes which shape the Martian atmosphere and its long-term evolution. A good knowledge of the variability of this parameter is thus very important in order to gain a deeper understanding of the present-day escape rate and of the evolutive history of Mars. We have used a ground-to-exosphere Global Climate Model, the LMD-MGCM, to simulate the variability of the temperatures at the Martian exobase during the last 9 Martian Years (MY24-MY32, approximately 17 terrestrial years). The simulations include for the first time a realistic day-to-day variability of the UV solar flux. The simulated temperatures are in good agreement with the exospheric temperatures derived from Precise Orbit Determination of Mars Global Surveyor. A significant inter-annual variability of the temperatures, due to both the 11 year solar cycle and the variability of the dust load in the lower atmosphere, is predicted by the model. The variation in the solar output produced by the 27 day solar rotation cycle is seen in the simulated exobase temperatures. We also find that the global dust storms in MY25 and MY28 significantly impact the temperatures at the exobase. These results underline the importance of properly taking into account the dust and solar variabilities to simulate the upper atmosphere of Mars.

  3. Combining Satellite Data and Models to Assess the Impacts of Urbanization on the Continental US Surface Climate

    Science.gov (United States)

    Bounoua, L.; Zhang, P.; Imhoff, M.; Santanello, J.; Kumar, S.; Shepherd, M.; Quattrochi, D.; Silva, J.; Rosenzweigh, C.; Gaffin, S.; Mostovoy, G.

    2013-01-01

    Urbanization is one of the most important and long lasting forms of land transformation. Urbanization affects the surface climate in different ways: (1) by reduction of the vegetation fraction causing subsequent reduction in photosynthesis and plant s water transpiration, (2) by alternation of surface runoff and infiltration and their impacts on soil moisture and the water table, (3) by change in the surface albedo and surface energy partitioning, and (4) by transformation of the surface roughness length and modification of surface fluxes. Land cover and land use change maps including urban areas have been developed and will be used in a suite of land surface models of different complexity to assess the impacts of urbanization on the continental US surface climate. These maps and datasets based on a full range of available satellite data and ground observations will be used to characterize distant-past (pre-urban), recent-past (2001), present (2010), and near future (2020) land cover and land use changes. The main objective of the project is to assess the impacts of these land transformation on past, current and near-future climate and the potential feedbacks from these changes on the atmospheric, hydrologic, biological, and socio-economic properties beyond the immediate metropolitan regions of cities and their near suburbs. The WRF modeling system will be used to explore the nature and the magnitude of the two-way interactions between urban lands and the atmosphere and assess the overall regional dynamic effect of urban expansion on the northeastern US weather and climate

  4. Analysis of the role of urban vegetation in local climate of Budapest using satellite measurements

    Science.gov (United States)

    Pongracz, Rita; Bartholy, Judit; Dezso, Zsuzsanna; Fricke, Cathy

    2016-08-01

    Urban areas significantly modify the natural environment due to the concentrated presence of humans and the associated anthropogenic activities. In order to assess this effect, it is essential to evaluate the relationship between urban and vegetated surface covers. In our study we focused on the Hungarian capital, Budapest, in which about 1.7 million inhabitants are living nowadays. The entire city is divided by the river Danube into the hilly, greener Buda side on the west, and the flat, more densely built-up Pest side on the east. Most of the extended urban vegetation, i.e., forests are located in the western Buda side. The effects of the past changing of these green areas are analyzed using surface temperature data calculated from satellite measurements in the infrared channels, and NDVI (Normalized Difference Vegetation Index) derived from visible and near-infrared satellite measurements. For this purpose, data available from sensor MODIS (Moderate Resolution Imaging Spectroradiometer) of NASA satellites (i.e., Terra and Aqua) are used. First, the climatological effects of forests on the urban heat island intensity are evaluated. Then, we also aim to evaluate the relationship of surface temperature and NDVI in this urban environment with special focus on vegetation-related sections of the city where the vegetation cover either increased or decreased remarkably.

  5. Estimating the Greenland ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR

    Directory of Open Access Journals (Sweden)

    X. Fettweis

    2013-03-01

    Full Text Available To estimate the sea level rise (SLR originating from changes in surface mass balance (SMB of the Greenland ice sheet (GrIS, we present 21st century climate projections obtained with the regional climate model MAR (Modèle Atmosphérique Régional, forced by output of three CMIP5 (Coupled Model Intercomparison Project Phase 5 general circulation models (GCMs. Our results indicate that in a warmer climate, mass gain from increased winter snowfall over the GrIS does not compensate mass loss through increased meltwater run-off in summer. Despite the large spread in the projected near-surface warming, all the MAR projections show similar non-linear increase of GrIS surface melt volume because no change is projected in the general atmospheric circulation over Greenland. By coarsely estimating the GrIS SMB changes from GCM output, we show that the uncertainty from the GCM-based forcing represents about half of the projected SMB changes. In 2100, the CMIP5 ensemble mean projects a GrIS SMB decrease equivalent to a mean SLR of +4 ± 2 cm and +9 ± 4 cm for the RCP (Representative Concentration Pathways 4.5 and RCP 8.5 scenarios respectively. These estimates do not consider the positive melt–elevation feedback, although sensitivity experiments using perturbed ice sheet topographies consistent with the projected SMB changes demonstrate that this is a significant feedback, and highlight the importance of coupling regional climate models to an ice sheet model. Such a coupling will allow the assessment of future response of both surface processes and ice-dynamic changes to rising temperatures, as well as their mutual feedbacks.

  6. Climate Monitoring Network on Maunakea - Master Station at Summit and Lower Elevation Satellite Stations

    Science.gov (United States)

    McKenzie, M. M.; Klasner, F.; Giambelluca, T. W.; Businger, S.

    2014-12-01

    Maunakea, a dormant shield volcano on the Big Island of Hawai'i, rises 13,796 feet above sea level, making it the highest point in the Pacific Basin. From sea floor to summit, it's the tallest mountain in the world. The high elevation, low air and light pollution, as well as dry weather year round make it the best location in the world for astronomy observations. The summit is home to 13 ground based telescope facilities. Like all alpine regions, it is an extremely fragile and unique ecosystem because of the harsh conditions and short growing seasons located at high altitudes. The summit is home to several federal and/or state protected species. It supports 11 species of arthropods found nowhere else on Earth. Most noted of these is the Wēkiu bug, whose habitat has been altered by the infrastructural development on the mountain. Arthropod habitat model development has highlighted gaps in climate information, for example, lack of climate precipitation data, snow data and reliable temperature data. Furthermore, in tropical regions, precipitation is the most variable climate component due to topography and local winds. The telescopes collect weather data for the purpose of knowing when it is dry and clear for astronomical observation. Although existing weather stations associated with the telescopes meet some weather and climate monitoring needs, it cannot address the full range of issues needed due to technological limitation and site design. Precipitation does not occur often and is likely to be in the form of snow or ice. Snow cover data has not been directly recorded despite astronomical recording of other meteorological data that began in the1960s. Therefore, the need to monitor the weather and climate in a long-term and well-calibrated way is critical for management of the ecosystems on the slopes of Maunakea. Long-term weather and climate monitoring stations are the primary building blocks for research partnerships, which encourage collaboration and ultimately

  7. Land surface phenological response to decadal climate variability across Australia using satellite remote sensing

    Science.gov (United States)

    Broich, M.; Huete, A.; Tulbure, M. G.; Ma, X.; Xin, Q.; Paget, M.; Restrepo-Coupe, N.; Davies, K.; Devadas, R.; Held, A.

    2014-05-01

    Land surface phenological cycles of vegetation greening and browning are influenced by variability in climatic forcing. Quantitative information on phenological cycles and their variability is important for agricultural applications, wildfire fuel accumulation, land management, land surface modeling, and climate change studies. Most phenology studies have focused on temperature-driven Northern Hemisphere systems, where phenology shows annually reoccurring patterns. Yet, precipitation-driven non-annual phenology of arid and semi-arid systems (i.e. drylands) received much less attention, despite the fact that they cover more than 30% of the global land surface. Here we focused on Australia, the driest inhabited continent with one of the most variable rainfall climates in the world and vast areas of dryland systems. Detailed and internally consistent studies investigating phenological cycles and their response to climate variability across the entire continent designed specifically for Australian dryland conditions are missing. To fill this knowledge gap and to advance phenological research, we used existing methods more effectively to study geographic and climate-driven variability in phenology over Australia. We linked derived phenological metrics with rainfall and the Southern Oscillation Index (SOI). We based our analysis on Enhanced Vegetation Index (EVI) data from the MODerate Resolution Imaging Spectroradiometer (MODIS) from 2000 to 2013, which included extreme drought and wet years. We conducted a continent-wide investigation of the link between phenology and climate variability and a more detailed investigation over the Murray-Darling Basin (MDB), the primary agricultural area and largest river catchment of Australia. Results showed high inter- and intra-annual variability in phenological cycles. Phenological cycle peaks occurred not only during the austral summer but at any time of the year, and their timing varied by more than a month in the interior of the

  8. Land surface phenological response to decadal climate variability across Australia using satellite remote sensing

    Directory of Open Access Journals (Sweden)

    M. Broich

    2014-05-01

    Full Text Available Land surface phenological cycles of vegetation greening and browning are influenced by variability in climatic forcing. Quantitative information on phenological cycles and their variability is important for agricultural applications, wildfire fuel accumulation, land management, land surface modeling, and climate change studies. Most phenology studies have focused on temperature-driven Northern Hemisphere systems, where phenology shows annually reoccurring patterns. Yet, precipitation-driven non-annual phenology of arid and semi-arid systems (i.e. drylands received much less attention, despite the fact that they cover more than 30% of the global land surface. Here we focused on Australia, the driest inhabited continent with one of the most variable rainfall climates in the world and vast areas of dryland systems. Detailed and internally consistent studies investigating phenological cycles and their response to climate variability across the entire continent designed specifically for Australian dryland conditions are missing. To fill this knowledge gap and to advance phenological research, we used existing methods more effectively to study geographic and climate-driven variability in phenology over Australia. We linked derived phenological metrics with rainfall and the Southern Oscillation Index (SOI. We based our analysis on Enhanced Vegetation Index (EVI data from the MODerate Resolution Imaging Spectroradiometer (MODIS from 2000 to 2013, which included extreme drought and wet years. We conducted a continent-wide investigation of the link between phenology and climate variability and a more detailed investigation over the Murray–Darling Basin (MDB, the primary agricultural area and largest river catchment of Australia. Results showed high inter- and intra-annual variability in phenological cycles. Phenological cycle peaks occurred not only during the austral summer but at any time of the year, and their timing varied by more than a month in

  9. Detection and Mapping of Ice Clouds in Mars' Mesosphere

    Science.gov (United States)

    Sefton-Nash, E.; Teanby, N. A.; Calcutt, S. B.; Hurley, J.; Irwin, P. G. J.

    2012-03-01

    We map ice cloud occurrence in Mars' mesosphere using > 2 Mars years worth of limb spectra acquired by the Mars Climate Sounder. We find two distinct seasonal regimes with short periods/latitudes of increased formation and limited longitudinal bias.

  10. Assessment of Satellite-Derived Essential Climate Variables in the Terrestrial Domain: Overview and Status of the CEOS LPV Subgroup

    Science.gov (United States)

    Roman, M. O.

    2015-12-01

    The validation of satellite-derived terrestrial observations has perennially faced the challenge of finding a consistent set of in-situ measurements that can both cover a wide range of surface conditions and provide timely and traceable product accuracy and uncertainty information. The Committee on Earth Observation Satellites (CEOS), the space arm of the Group on Earth Observations (GEO), plays a key role in coordinating the land product validation process. The Land Product Validation (LPV) sub-group of the CEOS Working Group on Calibration and Validation (WGCV) aims to address the challenges associated with the validation of global land products. This paper will provide a status of LPV subgroup focus area activities, which cover seven Global Climate Observing System (GCOS) terrestrial Essential Climate Variables (ECVs): (1) Snow Cover, (2) Surface Albedo, (3) Land Cover, (4) Leaf Area Index, (5) Fraction of Absorbed Photosynthetically Active Radiation (FAPAR), (6) Active Fires, and (7) Soil Moisture; as well as two additional variables (Land Surface Phenology and Land Surface Temperature), which are deemed of high priority of the LPV community. A primary focus of LPV is the implementation of a global validation framework for product intercomparison and validation (fig. 1). This framework is based on a citable protocol, fiducial reference data, and automated subsetting. Ideally, each of these parts will be integrated into an online platform where quantitative tests are run, and standardized intercomparison and validation results reported for all products used in the validation exercise. The establishment of consensus guidelines for in situ measurements as well as inter-comparison of trends derived from independently-obtained reference data and derived products will enhance coordination of the scientific needs of the Earth system communities with global LPV activities (http://lpvs.gsfc.nasa.gov/).

  11. Mapping the northern plains of Mars: origins, evolution and response to climate change - a new overview of the recent ice-related landforms in Utopia Planitia

    Science.gov (United States)

    Costard, Francois; Sejourne, Antoine; Losiak, Ania; Swirad, Zusanna; Balm, Matthew; Conway, Susan; Gallagher, Colman; van-Gassel, Stephan; Hauber, Ernst; Johnsson, Andreas; Kereszturi, Akos; Platz, Thomas; Ramsdale, Jason; Reiss, Dennis; Skinner, James

    2015-04-01

    An ISSI (International Space Science Institute) international team has been convened to study the Northern Plain of Mars. The northern plains of Mars are extensive, geologically young, low-lying areas that contrast in age and relief to Mars' older, heavily cratered, southern highlands. Mars' northern plains are characterised by a wealth of landforms and landscapes that have been inferred to be related to the presence of ice or ice-rich material. Such landforms include 'scalloped' pits and depressions, polygonally-patterned grounds, and viscous flow features similar in form to terrestrial glacial or ice-sheet landforms. Furthermore, new (within the last few years) impact craters have exposed ice in the northern plains, and spectral data from orbiting instruments have revealed the presence of tens of percent by weight of water within the upper most ~50 cm of the martian surface at high latitudes. The western Utopia Planitia contains numerous relatively young ice-related landforms (Utopia Planitia along a long strip from ~30N to ~80N latitude and about 250km wide. The goals are to: (i) map the geographical distribution of the ice-related landforms; (ii) identify their association with subtly-expressed geological units and; (iii) discuss the climatic modifications of the ice-rich permafrost in UP. Our work combines a study with CTX (5-6 m/pixel) and HRSC (~12.5-50 m/pixel) images, supported by higher resolution HiRISE (25 cm/pixel) and MOC (~2 m/pixel) and a comparison with analogous landforms on Earth.

  12. An Evaluation of Antarctica as a Calibration Target for Passive Microwave Satellite Missions with Climate Data Record Applications

    Science.gov (United States)

    Kim, E. J.

    2011-12-01

    surface salinity, both important climate variables. Science studies involving these variables can now take advantage of new satellite L-band observations. The first mission with regular global passive microwave observations at L-band is the European Space Agency's Soil Moisture and Ocean Salinity (SMOS), launched November, 2009. A second mission, NASA's Aquarius, was launched June, 2011. A third mission, NASA's Soil Moisture Active Passive (SMAP) is scheduled to launch in 2014. Together, these three missions may provide a decade-long data record-provided that they are intercalibrated. The intercalibration is best performed at the radiance (brightness temperature) level, and Antarctica is proving to be a key calibration target. However, Antarctica has thus far not been fully characterized as a potential target. This paper will present evaluations of Antarctica as a microwave calibration target for the above satellite missions. Preliminary analyses have identified likely target areas, such as the vicinity of Dome-C and larger areas within East Antarctica. Physical sources of temporal and spatial variability of polar firn are key to assessing calibration uncertainty. These sources include spatial variability of accumulation rate, compaction, surface characteristics (dunes, micro-topography), wind patterns, and vertical profiles of density and temperature. Using primarily SMOS data, variability is being empirically characterized and attempts are being made to attribute observed variability to physical sources. One expected outcome of these studies is the potential discovery of techniques for remotely sensing--over all of Antarctica-parameters such as surface temperature.

  13. Seeking an optimal algorithm for a new satellite-based Sea Ice Drift Climate Data Record : Motivations, plans and initial results from the ESA CCI Sea Ice project

    DEFF Research Database (Denmark)

    Lavergne, T.; Dybkjær, Gorm; Girard-Ardhuin, Fanny

    relevant satellite and “ground-truth” data, building the Round-Robin Data Package for testing the algorithms, and finally selection of the most promising algorithm(s) for processing of a new sea ice drift climate dataset. Specific efforts are dedicated to the definition of per-grid-cell uncertainties...

  14. Seeking an optimal algorithm for a new satellite-based Sea Ice Drift Climate Data Record : Motivations, plans and initial results from the ESA CCI Sea Ice project

    DEFF Research Database (Denmark)

    Lavergne, T.; Dybkjær, Gorm; Girard-Ardhuin, Fanny

    relevant satellite and “ground-truth” data, building the Round-Robin Data Package for testing the algorithms, and finally selection of the most promising algorithm(s) for processing of a new sea ice drift climate dataset. Specific efforts are dedicated to the definition of per-grid-cell uncertainties...

  15. Spatial and Temporal Patterns of Blowing Snow Flux and Related Near-Surface Atmospheric Processes over Antarctica (2001-2011) from the Modèle Atmosphérique Régionale (MAR), Assessed With In Situ and Satellite Data

    Science.gov (United States)

    Datta, Rajashree; Tedesco, Marco; Fettweis, Xavier; Gallee, Hubert; Booth, James

    2015-04-01

    The effects of blowing snow (both erosion and sublimation) have a substantial impact on thermodynamic processes on the Antarctic Ice sheet and are a significant source of uncertainty in surface mass balance estimates. In order to capture effects specific to blowing snow at the continental scale, two versions of the model Modèle Atmosphérique Régionale (MAR) RCM have been run at a 50 km resolution over Antarctica for the period 2000-2011. The two MAR configurations are identical except for the implementation of blowing snow dynamics. The model is forced at the boundaries with 6-hourly reanalysis data provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). The differences in surface and atmospheric outputs between the models can highlight the cumulative effects of blowing snow. Due to the difficulty of obtaining reliable large-scale measurements of blowing snow phenomena directly, comparisons of near-surface atmospheric variables between model outputs and satellite as well as in-situ data are necessary to assess the success of the blowing snow physics implemented in the model. For the purposes of assessment, we will use available surface temperature and pressure data from Automatic Weather Stations as well as radiosonde data at the ice sheet margins (made available by the University of Wisconsin-Madison). Additionally, satellite data at multiple atmospheric levels will be provided from the Atmospheric Infrared Sounder (available from NASA Goddard and the Jet Propulsion Labs). Finally, Empirical Orthogonal Function (EOF) analysis will be employed to find the most prominent spatio-temporal patterns of blowing snow flux with the seasonal and decadal trend removed. Model output composites of anomalies for the time series produced can suggest the large-scale climate dynamics which contribute to prominent patterns of blowing snow flux. Spatial trends of correlations between model output and satellite/in situ during these time-series should help to

  16. Satellite-based characterization of climatic conditions before large-scale general flowering events in Peninsular Malaysia

    Science.gov (United States)

    Azmy, Muna Maryam; Hashim, Mazlan; Numata, Shinya; Hosaka, Tetsuro; Noor, Nur Supardi Md.; Fletcher, Christine

    2016-08-01

    General flowering (GF) is a unique phenomenon wherein, at irregular intervals, taxonomically diverse trees in Southeast Asian dipterocarp forests synchronize their reproduction at the community level. Triggers of GF, including drought and low minimum temperatures a few months previously has been limitedly observed across large regional scales due to lack of meteorological stations. Here, we aim to identify the climatic conditions that trigger large-scale GF in Peninsular Malaysia using satellite sensors, Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS), to evaluate the climatic conditions of focal forests. We observed antecedent drought, low temperature and high photosynthetic radiation conditions before large-scale GF events, suggesting that large-scale GF events could be triggered by these factors. In contrast, we found higher-magnitude GF in forests where lower precipitation preceded large-scale GF events. GF magnitude was also negatively influenced by land surface temperature (LST) for a large-scale GF event. Therefore, we suggest that spatial extent of drought may be related to that of GF forests, and that the spatial pattern of LST may be related to that of GF occurrence. With significant new findings and other results that were consistent with previous research we clarified complicated environmental correlates with the GF phenomenon.

  17. Using records from submarine, aircraft and satellite to evaluate climate model simulations of Arctic sea ice thickness

    Directory of Open Access Journals (Sweden)

    J. Stroeve

    2014-04-01

    Full Text Available Arctic sea ice thickness distributions from models participating in the World Climate Research Programme Coupled Model Intercomparison Project Phase 5 are evaluated against observations from submarines, aircraft and satellites. While it's encouraging that the mean thickness distributions from the models are in general agreement with observations, the spatial patterns of sea ice thickness are poorly represented in most models. The poor spatial representation of thickness patterns is associated with a failure of models to represent details of the mean atmospheric circulation pattern that governs the transport and spatial distribution of sea ice. The climate models as a whole also tend to underestimate the rate of ice volume loss from 1979 to 2013, though the multi-model ensemble mean trend remains within the uncertainty of that from the Pan-Arctic Ice Ocean Modeling and Assimilation System. These results raise concerns regarding the ability of CMIP5 models to realistically represent the processes driving the decline of Arctic sea ice and project the timing of when a seasonally ice-free Arctic may be realized.

  18. Using Satellite Data to Build Climate Resilience: A Novel East Africa Drought Monitor

    Science.gov (United States)

    Slinski, K.; Hogue, T. S.; McCray, J. E.

    2016-12-01

    East Africa is affected by recurrent drought. The 2015-2016 El Niño triggered a severe drought across East Africa causing serious impacts to regional water security, health, and livelihoods. Ethiopia was the hardest hit, with the United Nations Office for the Coordination of Humanitarian Affairs calling the recent drought the worst in 50 years. Resources to monitor the severity and progression of droughts are a critical component to disaster risk reduction, but are challenging to implement in regions with sparse data collection networks such as East Africa. Satellite data is used by the United Nations Food and Agriculture Organization Global Information and Early Warning System, the USAID Famine Early Warning System, and the Africa Drought and Flood Monitor. These systems use remotely sensed vegetation, soil moisture, and meteorological data to develop drought indices. However, they do not directly monitor impacts to water resources, which is necessary to appropriately target drought mitigation efforts. The current study combines new radar data from the European Space Agency's Sentinel-1 mission with satellite imagery to perform a retrospective analysis of the impact of the 2015-2016 drought in East Africa on regional surface water. Inland water body extents during the drought are compared to historical trends to identify the most severely impacted areas. The developed tool has the potential to support on-the-ground humanitarian relief efforts and to refine predictions of water scarcity and crop impacts from existing hydrologic models and famine early warning systems.

  19. A New Formulation for Fresh Snow Density over Antarctica for the regional climate model Modèle Atmosphérique Régionale (MAR).

    Science.gov (United States)

    Tedesco, M.; Datta, R.; Fettweis, X.; Agosta, C.

    2015-12-01

    Surface-layer snow density is important to processes contributing to surface mass balance, but is highly variable over Antarctica due to a wide range of near-surface climate conditions over the continent. Formulations for fresh snow density have typically either used fixed values or been modeled empirically using field data that is limited to specific seasons or regions. There is also currently limited work exploring how the sensitivity to fresh snow density in regional climate models varies with resolution. Here, we present a new formulation compiled from (a) over 1600 distinct density profiles from multiple sources across Antarctica and (b) near-surface variables from the regional climate model Modèle Atmosphérique Régionale (MAR). Observed values represent coastal areas as well as the plateau, in both West and East Antarctica (although East Antarctica is dominant). However, no measurements are included from the Antarctic Peninsula, which is both highly topographically variable and extends to lower latitudes than the remainder of the continent. In order to assess the applicability of this fresh snow density formulation to the Antarctic Peninsula at high resolutions, a version of MAR is run for several years both at low-resolution at the continental scale and at a high resolution for the Antarctic Peninsula alone. This setup is run both with and without the new fresh density formulation to quantify the sensitivity of the energy balance and SMB components to fresh snow density. Outputs are compared with near-surface atmospheric variables available from AWS stations (provided by the University of Wisconsin Madison) as well as net accumulation values from the SAMBA database (provided from the Laboratoire de Glaciologie et Géophysique de l'Environnement).

  20. Life, death and revival of debris-flow fans on Earth and Mars : fan dynamics and climatic inferences

    NARCIS (Netherlands)

    de Haas, T.

    2016-01-01

    Alluvial fans are ubiquitous landforms in high-relief regions on Earth and Mars. They have a semi-conical shape and are located at the transition between highlands and adjacent basins. Alluvial fans can form by a range of processes including debris flows, which are water-laden masses of soil and

  1. Life, death and revival of debris-flow fans on Earth and Mars : fan dynamics and climatic inferences

    NARCIS (Netherlands)

    de Haas, T.

    2016-01-01

    Alluvial fans are ubiquitous landforms in high-relief regions on Earth and Mars. They have a semi-conical shape and are located at the transition between highlands and adjacent basins. Alluvial fans can form by a range of processes including debris flows, which are water-laden masses of soil and roc

  2. Understanding Hydrological and Climate Conditions on Early Mars Through Sulfate Cycling and Microbial Activity in Terrestrial Volcanic Systems

    Science.gov (United States)

    Szynkiewicz, A.; Mikucki, J.; Vaniman, D.

    2017-10-01

    Our study is a type of Earth-based investigation in a Mars-analog environment that allows for determination of how changing wet and dry conditions in active volcanic/hydrothermal system affect sulfate fluxes into surface water and groundwater.

  3. Life, death and revival of debris-flow fans on Earth and Mars : fan dynamics and climatic inferences

    NARCIS (Netherlands)

    de Haas, T.

    2016-01-01

    Alluvial fans are ubiquitous landforms in high-relief regions on Earth and Mars. They have a semi-conical shape and are located at the transition between highlands and adjacent basins. Alluvial fans can form by a range of processes including debris flows, which are water-laden masses of soil and roc

  4. Elevated Heat Pump hypothesis validation by using satellite data and CMIP5 climate model simulations

    Science.gov (United States)

    Biondi, R.; Cagnazzo, C.; Cairo, F.; Fierli, F.

    2016-12-01

    Air pollution assumes an important role for the health of the south Asian countries population due to the increasing emission of atmospheric pollutants connected to the population growth and industrial development. At the same time the monsoon rainfall trends and patterns have been changed causing serious economic and societal impacts. In this study we have analyzed the link between the aerosols and the monsoon system focusing the attention on a specific mechanism: the Elevated Heat Pump (EHP) hypothesis. According to the EHP the load of dust, organic carbon and black carbon in the pre-monsoon season over the Indo-Gangetic Plain and the foothills of the Himalayas induces enhanced warming in the middle and upper troposphere and changes the convection patterns. As a consequence the rainfall over northern India in late spring and early summer increases and the rainfall in all India in late summer decreases. However, there are still debated conclusions and large uncertainties in this proposed mechanism with ambiguity and uncertainties coming from the lack of real observations and to the consistency of the measurements. By using Historical Natural runs of 3 different Coupled Model Intercomparison Project Phase 5 (CMIP5) models with interactive aerosol loading, we have analysed the variation of precipitation and atmospheric temperature in correspondence to high and low aerosol load years in a time range of 160 years. For deepening the study and validating the model results, we have also included in our analyses the International Satellite Cloud Climatology Project (ISCCP) Deep Convective Tracking Database and the GPS Radio Occultation (RO) measurements. Our preliminary results with models and the two satellite measurements do not show significant evidence of EHP in terms of convection patterns, while the middle and upper troposphere thermal structure is consistent with previous findings.

  5. Application of Satellite Remote Sensing to Identify Climatic and Anthropogenic Changes Related to Water and Health Conditions in Emerging Megacities

    Science.gov (United States)

    Akanda, A. S.; Serman, E. A.; Jutla, A.

    2014-12-01

    focuses on stretching this understanding to water and health implications in this growing megacity and adjoining slum areas, and how satellite remote sensing data products and derived knowledge can inform urban planning, water management, and public health sectors to adapt to these climatic and anthropogenic changes for the benefit of societies.

  6. A Satellite-Derived Upper-Tropospheric Water Vapor Transport Index for Climate Studies

    Science.gov (United States)

    Jedlovec, Gray J.; Lerner, Jeffrey A.; Atkinson, Robert J.

    1998-01-01

    A new approach is presented to quantify upper-level moisture transport from geostationary satellite data. Daily time sequences of Geostationary Operational Environmental Satellite GOES-7 water vapor imagery were used to produce estimates of winds and water vapor mixing ratio in the cloud-free region of the upper troposphere sensed by the 6.7- microns water vapor channel. The winds and mixing ratio values were gridded and then combined to produce a parameter called the water vapor transport index (WVTI), which represents the magnitude of the two-dimensional transport of water vapor in the upper troposphere. Daily grids of WVTI, meridional moisture transport, mixing ratio, pressure, and other associated parameters were averaged to produce monthly fields for June, July, and August (JJA) of 1987 and 1988 over the Americas and surrounding oceanic regions, The WVTI was used to compare upper-tropospheric moisture transport between the summers of 1987 and 1988, contrasting the latter part of the 1986/87 El Nino event and the La Nina period of 1988. A similar product derived from the National Centers for Environmental Prediction (NCEP)-National Center for Atmospheric Research (NCAR) 40-Year Reanalysis Project was used to help to validate the index. Although the goal of this research was to describe the formulation and utility of the WVTI, considerable insight was obtained into the interannual variability of upper-level water vapor transport. Both datasets showed large upper-level water vapor transport associated with synoptic features over the Americas and with outflow from tropical convective systems. Minimal transport occurred over tropical and subtropical high pressure regions where winds were light. Index values from NCEP-NCAR were 2-3 times larger than that determined from GOES. This difference resulted from large zonal wind differences and an apparent overestimate of upper-tropospheric moisture in the reanalysis model. A comparison of the satellite-derived monthly

  7. An Evaluation of Antarctica as a Calibration Target for Passive Microwave Satellite Missions with Climate Data Record Applications

    Science.gov (United States)

    Kim, Edward

    2011-01-01

    Passive microwave remote sensing at L-band (1.4 GHz) is sensitive to soil moisture and sea surface salinity, both important climate variables. Science studies involving these variables can now take advantage of new satellite L-band observations. The first mission with regular global passive microwave observations at L-band is the European Space Agency's Soil Moisture and Ocean Salinity (SMOS), launched November, 2009. A second mission, NASA's Aquarius, was launched June, 201 I. A third mission, NASA's Soil Moisture Active Passive (SMAP) is scheduled to launch in 2014. Together, these three missions may provide a decade-long data record-provided that they are intercalibrated. The intercalibration is best performed at the radiance (brightness temperature) level, and Antarctica is proving to be a key calibration target. However, Antarctica has thus far not been fully characterized as a potential target. This paper will present evaluations of Antarctica as a microwave calibration target for the above satellite missions. Preliminary analyses have identified likely target areas, such as the vicinity of Dome-C and larger areas within East Antarctica. Physical sources of temporal and spatial variability of polar firn are key to assessing calibration uncertainty. These sources include spatial variability of accumulation rate, compaction, surface characteristics (dunes, micro-topography), wind patterns, and vertical profiles of density and temperature. Using primarily SMOS data, variability is being empirically characterized and attempts are being made to attribute observed variability to physical sources. One expected outcome of these studies is the potential discovery of techniques for remotely sensing--over all of Antarctica-parameters such as surface temperature.

  8. A sedimentary origin for intercrater plains north of the Hellas basin: Implications for climate conditions and erosion rates on early Mars

    Science.gov (United States)

    Salese, Francesco; Ansan, Veronique; Mangold, Nicolas; Carter, John; Ody, Anouck; Poulet, Francois; Ori, Gian Gabriele

    2016-11-01

    Understanding the origin (volcanic or sedimentary) and timing of intercrater plains is crucial for deciphering the geological evolution of Mars. We have produced a detailed geological map of the intercrater plains north of the Hellas basin, based on images from the Mars Express High-Resolution Stereo Camera, the Mars Reconnaissance High-Resolution Imaging Science Experiment, and Context. Erosional windows and fresh impact craters provide a way of studying the lithology of intercrater plain units. They are composed predominantly of light-toned sedimentary rocks with subhorizontal bedding over a broad extent (greater than tens of kilometers), showing cross-bedding stratifications locally. The broad extent, geometry, and flat topography of these sediments favor a formation by aqueous processes (alluvial and lacustrine) rather than airfall (eolian and volcaniclastic). The Late Noachian ( 3.7 Ga) sedimentary plains are locally covered by dark-toned, rough-textured lava flows of Late Hesperian age ( 3.3 Ga). Fe/Mg phyllosilicates were detected within sedimentary rocks, whereas volcanic rocks contain pyroxene and lack signatures of alteration, in agreement with interpretations made from texture and morphology. In erosional windows, the superimposition of sedimentary rocks by younger volcanic flows enables the estimation of an erosion rate of 1000 nm yr-1 during the Hesperian period (3.3-3.7 Ga). Thus, our study shows that an intense sedimentary cycle occurred on the northern rim of the Hellas basin before and during the Late Noachian, leading to the formation of widespread sedimentary plains, which were then eroded, in agreement with a gradual change in the climatic conditions in this period, and later covered by volcanic flows.

  9. Monitoring Crop Yield in USA Using a Satellite-Based Climate-Variability Impact Index

    Science.gov (United States)

    Zhang, Ping; Anderson, Bruce; Tan, Bin; Barlow, Mathew; Myneni, Ranga

    2011-01-01

    A quantitative index is applied to monitor crop growth and predict agricultural yield in continental USA. The Climate-Variability Impact Index (CVII), defined as the monthly contribution to overall anomalies in growth during a given year, is derived from 1-km MODIS Leaf Area Index. The growing-season integrated CVII can provide an estimate of the fractional change in overall growth during a given year. In turn these estimates can provide fine-scale and aggregated information on yield for various crops. Trained from historical records of crop production, a statistical model is used to produce crop yield during the growing season based upon the strong positive relationship between crop yield and the CVII. By examining the model prediction as a function of time, it is possible to determine when the in-season predictive capability plateaus and which months provide the greatest predictive capacity.

  10. Formation of gullies on Mars: link to recent climate history and insolation microenvironments implicate surface water flow origin.

    Science.gov (United States)

    Head, James W; Marchant, David R; Kreslavsky, Mikhail A

    2008-09-09

    Features seen in portions of a typical midlatitude Martian impact crater show that gully formation follows a geologically recent period of midlatitude glaciation. Geological evidence indicates that, in the relatively recent past, sufficient snow and ice accumulated on the pole-facing crater wall to cause glacial flow and filling of the crater floor with debris-covered glaciers. As glaciation waned, debris-covered glaciers ceased flowing, accumulation zones lost ice, and newly exposed wall alcoves continued as the location for limited snow/frost deposition, entrapment, and preservation. Analysis of the insolation geometry of this pole-facing crater wall, and similar occurrences in other craters at these latitudes on Mars, shows that they are uniquely favored for accumulation of snow and ice, and a relatively more rapid exposure to warmer summer temperatures. We show that, after the last glaciation, melting of residual snow and ice in alcoves could have formed the fluvial channels and sedimentary fans of the gullies. Recent modeling shows that top-down melting can occur in these microenvironments under conditions similar to those currently observed on Mars, if small amounts of snow or frost accumulate in alcoves and channels. Accumulation and melting is even more favored in the somewhat wetter, relatively recent geological past of Mars, after the period of active glaciation.

  11. Impact of spatial resolution on the modelling of the Greenland ice sheet surface mass balance between 1990–2010, using the regional climate model MAR

    Directory of Open Access Journals (Sweden)

    B. Franco

    2012-02-01

    Full Text Available With the aim to force an ice dynamical model, the Greenland ice sheet (GrIS surface mass balance (SMB was modelled at different spatial resolutions (15–50 km for the period 1990–2010, using the regional climate model MAR (Modèle Atmosphérique Régional forced by the ERA-INTERIM reanalysis. This comparison revealed that (i the inter-annual variability of the SMB components is consistent within the different spatial resolutions investigated, (ii the MAR model simulates heavier precipitation on average over the GrIS with diminishing spatial resolution, and (iii the SMB components (except precipitation can be derived from a simulation at lower resolution with an ''intelligent'' interpolation. This interpolation can also be used to approximate the SMB components over another topography/ice sheet mask of the GrIS. These results are important for the forcing of an ice dynamical model, needed to enable future projections of the GrIS contribution to sea level rise over the coming centuries.

  12. Assessment of climate variability of the Greenland ice sheet: Integration of in situ and satellite data

    Science.gov (United States)

    Steffen, K.; Abdalati, W.; Stroeve, J.; Stober, M.; Nolin, A.; Key, J.

    1995-01-01

    The proposed research involves the application of multispectral satellite data in combination with ground truth measurements to monitor surface properties of the Greenland ice sheet which are essential for describing the energy and mass of the ice sheet. Several key components of the energy balance are parameterized using satellite data and in situ measurements. The analysis will be done for a ten year time period in order to get statistics on the seasonal and interannual variations of the surface processes and the climatology. Our goal is to investigate to what accuracy and over what geographic areas large scale snow properties and radiative fluxes can be derived based upon a combination of available remote sensing and meterological data sets. Data analysis showed the following results: (1)cloud classification based on longwave sky radiation revealed that overcast sky occurred for 25% of the time in winter, and for 15% in spring and summer respectively (winter and summer both show the same occurrence of clear sky of approximately 26%); (2) comparison of aerodynamic profile method with eddy correlation method to derive sensible and latent heat flux showed good agreement in the diurnal cycle and the turbulent fluxes were underestimated with the aerodynamic method by 10 - 30% as compared to the in situ eddy flux method; (3) the katabatic wind shows a distinct diurnal cycle with a maximum in the morning (7-9 h solar time) and a minimum in the later afternoon (18 h solar time); (4) snow grain size was modeled with a surface energy balance model (SNTHERM) and compared with in situ measurements. Sharp decreases in the modeled snow grain size, caused by accumulation events such as precipitation and deposition, could be verified with observational data; (4) radiative transfer modeling of firn supports our beliefs that the observed trends in 18 and 19 GHz passive microwave brightness temperatures are attributable to accumulation rate changes (modeling also indicates the

  13. Seasonal Climate Variation and Caribou Availability: Modeling Sequential Movement Using Satellite-Relocation Data

    Directory of Open Access Journals (Sweden)

    Craig Nicolson

    2013-06-01

    Full Text Available Livelihood systems that depend on mobile resources must constantly adapt to change. For people living in permanent settlements, environmental changes that affect the distribution of a migratory species may reduce the availability of a primary food source, with the potential to destabilize the regional social-ecological system. Food security for Arctic indigenous peoples harvesting barren ground caribou (Rangifer tarandus granti depends on movement patterns of migratory herds. Quantitative assessments of physical, ecological, and social effects on caribou distribution have proven difficult because of the significant interannual variability in seasonal caribou movement patterns. We developed and evaluated a modeling approach for simulating the distribution of a migratory herd throughout its annual cycle over a multiyear period. Beginning with spatial and temporal scales developed in previous studies of the Porcupine Caribou Herd of Canada and Alaska, we used satellite collar locations to compute and analyze season-by-season probabilities of movement of animals between habitat zones under two alternative weather conditions for each season. We then built a set of transition matrices from these movement probabilities, and simulated the sequence of movements across the landscape as a Markov process driven by externally imposed seasonal weather states. Statistical tests showed that the predicted distributions of caribou were consistent with observed distributions, and significantly correlated with subsistence harvest levels for three user communities. Our approach could be applied to other caribou herds and could be adapted for simulating the distribution of other ungulates and species with similarly large interannual variability in the use of their range.

  14. Long Range River Discharge Forecasting Using the Gravity Recovery and Climate Experiment (GRACE) Satellite to Predict Conditions for Endemic Cholera

    Science.gov (United States)

    Jutla, A.; Akanda, A. S.; Colwell, R. R.

    2014-12-01

    Prediction of conditions of an impending disease outbreak remains a challenge but is achievable if the associated and appropriate large scale hydroclimatic process can be estimated in advance. Outbreaks of diarrheal diseases such as cholera, are related to episodic seasonal variability in river discharge in the regions where water and sanitation infrastructure are inadequate and insufficient. However, forecasting river discharge, few months in advance, remains elusive where cholera outbreaks are frequent, probably due to non-availability of geophysical data as well as transboundary water stresses. Here, we show that satellite derived water storage from Gravity Recovery and Climate Experiment Forecasting (GRACE) sensors can provide reliable estimates on river discharge atleast two months in advance over regional scales. Bayesian regression models predicted flooding and drought conditions, a prerequisite for cholera outbreaks, in Bengal Delta with an overall accuracy of 70% for upto 60 days in advance without using any other ancillary ground based data. Forecasting of river discharge will have significant impacts on planning and designing intervention strategies for potential cholera outbreaks in the coastal regions where the disease remain endemic and often fatal.

  15. Estimating carbon flux phenology with satellite-derived land surface phenology and climate drivers for different biomes: a synthesis of AmeriFlux observations.

    Directory of Open Access Journals (Sweden)

    Wenquan Zhu

    Full Text Available Carbon Flux Phenology (CFP can affect the interannual variation in Net Ecosystem Exchange (NEE of carbon between terrestrial ecosystems and the atmosphere. In this study, we proposed a methodology to estimate CFP metrics with satellite-derived Land Surface Phenology (LSP metrics and climate drivers for 4 biomes (i.e., deciduous broadleaf forest, evergreen needleleaf forest, grasslands and croplands, using 159 site-years of NEE and climate data from 32 AmeriFlux sites and MODIS vegetation index time-series data. LSP metrics combined with optimal climate drivers can explain the variability in Start of Carbon Uptake (SCU by more than 70% and End of Carbon Uptake (ECU by more than 60%. The Root Mean Square Error (RMSE of the estimations was within 8.5 days for both SCU and ECU. The estimation performance for this methodology was primarily dependent on the optimal combination of the LSP retrieval methods, the explanatory climate drivers, the biome types, and the specific CFP metric. This methodology has a potential for allowing extrapolation of CFP metrics for biomes with a distinct and detectable seasonal cycle over large areas, based on synoptic multi-temporal optical satellite data and climate data.

  16. Estimating carbon flux phenology with satellite-derived land surface phenology and climate drivers for different biomes: a synthesis of AmeriFlux observations.

    Science.gov (United States)

    Zhu, Wenquan; Chen, Guangsheng; Jiang, Nan; Liu, Jianhong; Mou, Minjie

    2013-01-01

    Carbon Flux Phenology (CFP) can affect the interannual variation in Net Ecosystem Exchange (NEE) of carbon between terrestrial ecosystems and the atmosphere. In this study, we proposed a methodology to estimate CFP metrics with satellite-derived Land Surface Phenology (LSP) metrics and climate drivers for 4 biomes (i.e., deciduous broadleaf forest, evergreen needleleaf forest, grasslands and croplands), using 159 site-years of NEE and climate data from 32 AmeriFlux sites and MODIS vegetation index time-series data. LSP metrics combined with optimal climate drivers can explain the variability in Start of Carbon Uptake (SCU) by more than 70% and End of Carbon Uptake (ECU) by more than 60%. The Root Mean Square Error (RMSE) of the estimations was within 8.5 days for both SCU and ECU. The estimation performance for this methodology was primarily dependent on the optimal combination of the LSP retrieval methods, the explanatory climate drivers, the biome types, and the specific CFP metric. This methodology has a potential for allowing extrapolation of CFP metrics for biomes with a distinct and detectable seasonal cycle over large areas, based on synoptic multi-temporal optical satellite data and climate data.

  17. Assessing the impact of urbanization on urban climate by remote satellite perspective: a case study in Danang city, Vietnam

    Science.gov (United States)

    Hoang Khanh Linh, N.; Van Chuong, H.

    2015-04-01

    Urban climate, one of the challenges of human being in 21 century, is known as the results of land use/cover transformation. Its characteristics are distinguished by different varieties of climatic conditions in comparison with those of less built-up areas. The alterations lead to "Urban Heat Island", in which temperature in urban places is higher than surrounding environment. This happens not only in mega cities but also in less urbanized sites. The results determine the change of land use/cover and land surface temperature in Danang city by using multi-temporal Landsat and ASTER data for the period of 1990-2009. Based on the supervised classification method of maximum likelihood algorithm, satellite images in 1990, 2003, 2009 were classified into five classes: water, forest, shrub, agriculture, barren land and built-up area. For accuracy assessment, the error metric tabulations of mapped classes and reference classes were made. The Kappa statistics, derived from error matrices, were over 80% for all of land use maps. An comparison change detection algorithm was made in three intervals, 1990-2003, 2003-2009 and 1990-2009. The results showed that built-up area increased from 8.95% to 17.87% between 1990 and 2009, while agriculture, shrub and barren decreased from 12.98% to 7.53%, 15.72% to 9.89% and 3.88% to 1.77% due to urbanization that resulted from increasing of urban population and economic development, respectively. Land surface temperature (LST) maps were retrieved from thermal infrared bands of Landsat and ASTER data. The result indicated that the temperature in study area increased from 39oC to 41oC for the period of 1990-2009. Our analysis showed that built-up area had the highest LST values, whereas water bodies had the least LST. This study is expected to be useful for decision makers to make an appropriate land use planning which can mitigate the effect to urban climate.

  18. Reconstructing the Paleo-Climate and Hydrology of Gale Crater, Mars in the Late Noachian and Hesperian Epochs

    Science.gov (United States)

    Horvath, D. G.; Andrews-Hanna, J. C.

    2017-10-01

    Using indicators of paleo-lake levels and the observed extent of aqueous alteration, hydrological modeling is used to constrain the climate and hydrology at Gale crater during the Noachian and Hesperian.

  19. Measuring the Value of Earth Observation Information with the Gravity Research and Climate Experiment (GRACE) Satellite

    Science.gov (United States)

    Bernknopf, R.; Kuwayama, Y.; Brookshire, D.; Macauley, M.; Zaitchik, B.; Pesko, S.; Vail, P.

    2014-12-01

    Determining how much to invest in earth observation technology depends in part on the value of information (VOI) that can be derived from the observations. We design a framework and then evaluate the value-in-use of the NASA Gravity Research and Climate Experiment (GRACE) for regional water use and reliability in the presence of drought. As a technology that allows measurement of water storage, the GRACE Data Assimilation System (DAS) provides information that is qualitatively different from that generated by other water data sources. It provides a global, reproducible grid of changes in surface and subsurface water resources on a frequent and regular basis. Major damages from recent events such as the 2012 Midwest drought and the ongoing drought in California motivate the need to understand the VOI from remotely sensed data such as that derived from GRACE DAS. Our conceptual framework models a dynamic risk management problem in agriculture. We base the framework on information from stakeholders and subject experts. The economic case for GRACE DAS involves providing better water availability information. In the model, individuals have a "willingness to pay" (wtp) for GRACE DAS - essentially, wtp is an expression of savings in reduced agricultural input costs and for costs that are influenced by regional policy decisions. Our hypothesis is that improvements in decision making can be achieved with GRACE DAS measurements of water storage relative to data collected from groundwater monitoring wells and soil moisture monitors that would be relied on in the absence of GRACE DAS. The VOI is estimated as a comparison of outcomes. The California wine grape industry has features that allow it to be a good case study and a basis for extrapolation to other economic sectors. We model water use in this sector as a sequential decision highlighting the attributes of GRACE DAS input as information for within-season production decisions as well as for longer-term water reliability.

  20. Time Scales for Discharge of Near-Equatorial WEH on Mars: Implications for a Recent Climate Change

    Science.gov (United States)

    Feldman, W. C.; Mellon, M. T.; Nelli, S.; Murphy, J. R.; Maurice, S.; Gasnault, O.

    2005-12-01

    Geomorphic studies of Martian mid-latitude features suggest that Mars has recently experienced an ice age. A mid-latitude water-ice cover could result from enhanced sublimation of residual water ice that presently covers portions of both polar caps. Such a change could be driven by changes in the orbital state of Mars, or in atmospheric conditions that led to a removal of the present residual south-polar CO2-ice veneer. Regardless of origin, such conditions would lead to the filling of near-surface pore volumes with water ice. After a change back to the present orbital or atmospheric state where low to mid latitude water-ice deposits are unstable, the pore-filling water ice would sublimate, and the ice table (the top of the ice-cemented layer) would recede downward. If the water-equivalent hydrogen (WEH) now observed at low to mid latitudes of Mars reflects such a process, then we can predict the time of the change from stable to unstable conditions as a function of surface temperature and apparent abundance of WEH. Resultant time scales range from about one hundred to 5000 Martian years. Such short time scales rule out an interpretation of the presently observed WEH distribution in terms of water-ice deposits from past obliquity cycles. If removal of the south polar CO2-ice veneer cannot increase the average hydration state of the atmosphere by a factor of two or more, then the measured low to mid latitude WEH distribution most likely does not reflect water ice. Instead, it must reflect the existence of one or more hydratable minerals.

  1. Life, death and revival of debris-flow fans on Earth and Mars : fan dynamics and climatic inferences

    OpenAIRE

    Haas, T.

    2016-01-01

    Alluvial fans are ubiquitous landforms in high-relief regions on Earth and Mars. They have a semi-conical shape and are located at the transition between highlands and adjacent basins. Alluvial fans can form by a range of processes including debris flows, which are water-laden masses of soil and rock with volumetric sediment concentrations exceeding 40%. In this thesis, I aim to (1) unravel the formative dynamics of debris-flow fans and, building on these insights, to (2) reconstruct hydrolog...

  2. SPHERES Mars Orbiting Sample Return External Orbiting Capture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Mars Sample Return (MSR) mission scenario utilizes a small Orbiting Sample (OS) satellite, launched from the surface of Mars, which will rendezvous with an...

  3. Assessing the response of area burned to changing climate in western boreal North America using a Multivariate Adaptive Regression Splines (MARS) approach

    Science.gov (United States)

    Balshi, M. S.; McGuire, A.D.; Duffy, P.; Flannigan, M.; Walsh, J.; Melillo, J.

    2009-01-01

    Fire is a common disturbance in the North American boreal forest that influences ecosystem structure and function. The temporal and spatial dynamics of fire are likely to be altered as climate continues to change. In this study, we ask the question: how will area burned in boreal North America by wildfire respond to future changes in climate? To evaluate this question, we developed temporally and spatially explicit relationships between air temperature and fuel moisture codes derived from the Canadian Fire Weather Index System to estimate annual area burned at 2.5?? (latitude ?? longitude) resolution using a Multivariate Adaptive Regression Spline (MARS) approach across Alaska and Canada. Burned area was substantially more predictable in the western portion of boreal North America than in eastern Canada. Burned area was also not very predictable in areas of substantial topographic relief and in areas along the transition between boreal forest and tundra. At the scale of Alaska and western Canada, the empirical fire models explain on the order of 82% of the variation in annual area burned for the period 1960-2002. July temperature was the most frequently occurring predictor across all models, but the fuel moisture codes for the months June through August (as a group) entered the models as the most important predictors of annual area burned. To predict changes in the temporal and spatial dynamics of fire under future climate, the empirical fire models used output from the Canadian Climate Center CGCM2 global climate model to predict annual area burned through the year 2100 across Alaska and western Canada. Relative to 1991-2000, the results suggest that average area burned per decade will double by 2041-2050 and will increase on the order of 3.5-5.5 times by the last decade of the 21st century. To improve the ability to better predict wildfire across Alaska and Canada, future research should focus on incorporating additional effects of long-term and successional

  4. Understanding of crop phenology using satellite-based retrievals and climate factors - a case study on spring maize in Northeast China plain

    Science.gov (United States)

    Shuai, Yanmin; Xie, Donghui; Wang, Peijuan; Wu, Menxin

    2014-03-01

    Land surface phenology is an efficient bio-indicator for monitoring terrestrial ecosystem variation in response to climate change. Numerous studies point out climate change plays an important role in modulating vegetation phenological events, especially in agriculture. In turn, surface changes caused by geo-biological processes can affect climate transition regionally and perhaps globally, as concluded by Intergovernmental Panel on Climate Change (IPCC) in 2001. Large amounts of research concluded that crops, as one of the most sensitive bio-indicators for climate change, can be strongly influenced by local weather such as temperature, moisture and radiation. Thus, investigating the details of weather impact and the feedback from crops can help improve our understanding of the interaction between crops and climate change at satellite scale. Our efforts start from this point, via case studies over the famous agriculture region in the Northeast China's plain to examine the response of spring maize under temperature and moisture stress. MODIS-based daily green vegetation information together with frequent field specification of the surface phenology as well as continuous measurements of the routine climatic factors during seven years (2003-2009) is used in this paper. Despite the obvious difference in scale between satellite estimations and field observations, the inter- and intra-annual variation of maize in seven-years' growth was captured successfully over three typical spring maize regions (Fuyu, Changling, and Hailun) in Northeast China. The results demonstrate that weather conditions such as changes of temperature and moisture stress provide considerable contribution to the year-to-year variations in the timing of spring maize phenological events.

  5. Parameterizing atmosphere-land surface exchange for climate models with satellite data: A case study for the Southern Great Plains CART site

    Science.gov (United States)

    Gao, W.

    High-resolution satellite data provide detailed, quantitative descriptions of land surface characteristics over large areas so that objective scale linkage becomes feasible. With the aid of satellite data, researchers examined the linearity of processes scaled up from 30 m to 15 km. If the phenomenon is scale invariant, then the aggregated value of a function or flux is equivalent to the function computed from aggregated values of controlling variables. The linear relation may be realistic for limited land areas having no large surface contrasts to cause significant horizontal exchange. However, for areas with sharp surface contrasts, horizontal exchange and different dynamics in the atmospheric boundary may induce nonlinear interactions, such as at interfaces of land-water, forest-farm land, and irrigated crops-desert steppe. The linear approach, however, represents the simplest scenario and is useful for developing an effective scheme for incorporating subgrid land surface processes into large-scale models. Our studies focus on coupling satellite data and ground measurements with a satellite-data-driven land surface model to parameterize surface fluxes for large-scale climate models. In this case study, we used surface spectral reflectance data from satellite remote sensing to characterize spatial and temporal changes in vegetation and associated surface parameters in an area of about 350 x 400 km covering the southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site of the US Department of Energy's Atmospheric Radiation Measurement (ARM) Program.

  6. Late Noachian Climate Of Mars: Constraints From Valley Network System Formation Times And The Intermittencies (Episodic/Periodic And Punctuated).

    Science.gov (United States)

    Head, James

    2017-04-01

    Formation of Late Noachian-Early Hesperian (LN-EH) valley network systems (VNS) signaled the presence of warm/wet conditions generating several hypotheses for climates permissive of these conditions. To constrain options for the ambient Noachian climate, we examine estimates for time required to carve channels/deltas and total duration implied by plausible intermittencies. Formation Times for VN, OBL, Deltas, Fans: A synthesis of required timescales show that even with the longest estimated continuous duration of VN formation/intermittencies, total time to carve the VN does not exceed 106 years, 273 K, hydrological system vertically integrated, and rainfall occurs to recharge the aquifer. Two subtypes: a) "Rainfall/Fluvial Erosion-Dominated Warm and Wet Model": "Rainfall and surface runoff" persist throughout Noachian to explain crater degradation, and a LN-EH short rapidly ending terminal epoch. b) "Recharge Evaporation/Evaporite Dominated Warm and Wet Model": Sustained period of equatorial/mid-latitude precipitation and a vertically integrated hydrological system driven by evaporative upwelling and fluctuating shallow water table playa environments account for sulfate evaporate environments at Meridiani Planum. Sustained temperatures >273 K are required for extended periods (107-108 years). 2) Cold and icy climate: Sustained background temperatures extremely low (MAT ˜225 K), cryosphere is globally continuous, hydrological system is horizontally stratified, separating groundwater system from surface; no combination of spin-axis/orbital perturbations can raise MAT to 273 K. Adiabatic cooling effects transfer water to high altitudes, leading to "Late Noachian Icy Highlands Model". VNS cannot form in this nominal climate environment without special circumstances (e.g., impacts or volcanic eruptions elevate of temperatures by >˜50 K to induce melting and fluvial/lacustrine activity). 3) Cold and Icy climate warmed by greenhouse gases: The climate is sustained cold

  7. Satellite-measured interannual variability of turbid river plumes off central-southern Chile: Spatial patterns and the influence of climate variability

    Science.gov (United States)

    Saldías, Gonzalo S.; Largier, John L.; Mendes, Renato; Pérez-Santos, Iván; Vargas, Cristian A.; Sobarzo, Marcus

    2016-08-01

    Ocean color imagery from MODIS (Moderate Resolution Imaging Spectroradiometer) onboard the Aqua platform is used to characterize the interannual variability of turbid river plumes off central-southern Chile. Emphasis is placed on the influence of climate fluctuations, namely El Niño Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), and the Antarctic Oscillation (AAO). Additional satellite data on wind, boat-based hydrographic profiles, and regional climate indices are used to identify the influence of climate variability on the generation of anomalous turbid river plumes. The evolution of salinity at a coastal station on the 90 m isobath between the Itata and Biobío Rivers shows a freshwater surface layer with salinity importance of long-term and high-resolution ocean color observations for studying the temporal evolution of river plumes.

  8. Mapping daily and seasonal evapotranspiration from irrigated crops using global climate grids and satellite imagery: Automation and methods comparison

    Science.gov (United States)

    Biggs, Trent W.; Marshall, Michael; Messina, Alex

    2016-09-01

    The surface energy balance algorithm for land (SEBAL) estimates land surface evapotranspiration (ET) from radiometric surface temperature (TR), but requires manual selection of calibration pixels, which can be impractical for mapping seasonal ET. Here pixel selection is automated and SEBAL implemented using global climate grids and satellite imagery. SEBAL is compared with the MOD16 algorithm, which uses remotely sensed data on vegetation condition to constrain reference ET from the Penman-Monteith equation. The difference between the evaporative fraction (Λ, range 0-1) from SEBAL and six eddy flux correlation towers was less than 0.10 for three of six towers, and less than 0.24 for all towers. SEBAL ET was moderately sensitive to surface roughness length and implementation over regions smaller than ˜10,000 km2 provided lower error than larger regions. Pixel selection based on TR had similar errors as those based on a vegetation index. For maize, MOD16 had lower error in mean seasonal evaporative fraction (-0.02) compared to SEBAL Λ (0.23), but MOD16 significantly underestimated the evaporative fraction from rice (-0.52) and cotton fields (-0.67) compared with SEBAL (-0.09 rice, -0.09 cotton). MOD16 had the largest error over short crops in the early growing season when vegetation cover was low but land surface was wet. Temperature-based methods like SEBAL can be automated and likely outperform vegetation-based methods in irrigated areas, especially under conditions of low vegetation cover and high soil evaporation.

  9. Climatic variability of transport in the upper layer of the Antarctic Circumpolar Current from hydrological and satellite data

    Science.gov (United States)

    Artamonov, Ju. V.; Fedirko, A. V.; Skripaleva, E. A.

    2016-12-01

    Based on the satellite altimetry dataset of sea level anomalies, the climatic hydrological database World Ocean Atlas-2009, ocean reanalysis ECMWF ORA-S3, and wind velocity components from NCEP/NCAR reanalysis, the interannual variability of Antarctic Circumpolar Current (ACC) transport in the ocean upper layer is investigated for the period 1959-2008, and estimations of correlative connections between ACC transport and wind velocity components are performed. It has been revealed that the maximum (by absolute value) linear trends of ACC transport over the last 50 years are observed in the date-line region, in the Western and Eastern Atlantic and the western part of the Indian Ocean. The greatest increase in wind velocity for this period for the zonal component is observed in Drake Passage, at Greenwich meridian, in the Indian Ocean near 90° E, and in the date-line region; for the meridional component, it is in the Western and Eastern Pacific, in Drake Passage, and to the south of Africa. It has been shown that the basic energy-carrying frequencies of interannual variability of ACC transport and wind velocity components, as well as their correlative connections, correspond to the periods of basic large-scale modes of atmospheric circulation: multidecadal and interdecadal oscillations, Antarctic Circumpolar Wave, Southern Annual Mode, and Southern Oscillation. A significant influence of the wind field on the interannual variability of ACC transport is observed in the Western Pacific (140° E-160° W) and Eastern Pacific; Drake Passage and Western Atlantic (90°-30° W); in the Eastern Atlantic and Western Indian Ocean (10°-70° E). It has been shown in the Pacific Ocean that the ACC transport responds to changes of the meridional wind more promptly than to changes of the zonal wind.

  10. Impact of leadership styles on the institutional climate of the Unidad María Auxiliadora High School in Riobamba

    Directory of Open Access Journals (Sweden)

    Luisa Lozado

    2013-12-01

    Full Text Available This article describes two variables that are key in any organization: leadership styles and institutional climate. I analyze different key factors that come into play: the influence that institutional climate and leadership has over members in an educational community. For this purpose, I examine various leadership theories by different authors that highlight the warmth and quality perceived by its members, theories that reflect people ́s behavior, manifested in a diversity of styles, which have been selected based on the classification proposed by Bass and Avolio in “Transformational, transactional, and laissez-faire leadership styles” (Estilos de liderazgo transformacionales, transaccionaes y de laissez-faire.The mixed qualitative and quantitative focus with a correlational descriptive reach, shows that leadership styles put into practice in an institution have an impact on its climate, generating a pleasant, motivating, happy, familiar environment with a sense of belonging; or a negative, discouraging, and indifferent one. The more democratic, participatory, and transformational the leadership style is, the warmer, more familiar, and trustworthy the institutional climate becomes.

  11. Statistical Modeling of Sea Ice Concentration Using Satellite Imagery and Climate Reanalysis Data in the Barents and Kara Seas, 1979–2012

    Directory of Open Access Journals (Sweden)

    Jihye Ahn

    2014-06-01

    Full Text Available Extensive sea ice over Arctic regions is largely involved in heat, moisture, and momentum exchanges between the atmosphere and ocean. Some previous studies have been conducted to develop statistical models for the status of Arctic sea ice and showed considerable possibilities to explain the impacts of climate changes on the sea ice extent. However, the statistical models require improvements to achieve better predictions by incorporating techniques that can deal with temporal variation of the relationships between sea ice concentration and climate factors. In this paper, we describe the statistical approaches by ordinary least squares (OLS regression and a time-series method for modeling sea ice concentration using satellite imagery and climate reanalysis data for the Barents and Kara Seas during 1979–2012. The OLS regression model could summarize the overall climatological characteristics in the relationships between sea ice concentration and climate variables. We also introduced autoregressive integrated moving average (ARIMA models because the sea ice concentration is such a long-range dataset that the relationships may not be explained by a single equation of the OLS regression. Temporally varying relationships between sea ice concentration and the climate factors such as skin temperature, sea surface temperature, total column liquid water, total column water vapor, instantaneous moisture flux, and low cloud cover were modeled by the ARIMA method, which considerably improved the prediction accuracies. Our method may also be worth consideration when forecasting future sea ice concentration by using the climate data provided by general circulation models (GCM.

  12. Spectral characteristics and feature selection of satellite remote sensing data for climate and anthropogenic changes assessment in Bucharest area

    Science.gov (United States)

    Zoran, Maria; Savastru, Roxana; Savastru, Dan; Tautan, Marina; Miclos, Sorin; Cristescu, Luminita; Carstea, Elfrida; Baschir, Laurentiu

    2010-05-01

    was suggested. On the basis of analyzing the information quantity of bands, correlation between different bands, spectral absorption characteristics of objects and object separability in bands, a fundamental method of optimum band selection and feature extraction from remote sensing data was discussed. Spectral signatures of different terrain features have been used to extract structural patterns aiming to separate surface units and to classify the general categories. The synergetic analysis and interpretation of the different satellite images (LANDSAT: TM, ETM; MODIS, IKONOS) acquired over a period of more than 20 years reveals significant aspects regarding impacts of climate and anthropogenic changes on urban/periurban environment. It was delimited residential zones of industrial zones which are very often a source of pollution. An important role has urban green cover assessment. Have been emphasized the particularities of the functional zones from different points of view: architectural, streets and urban surface traffic, some components of urban infrastructure as well as habitat quality. The growth of Bucharest urban area in Romania has been a result of a rapid process of industrialization, and also of the increase of urban population. Information on the spatial pattern and temporal dynamics of land cover and land use of urban areas is critical to address a wide range of practical problems relating to urban regeneration, urban sustainability and rational planning policy.

  13. Effects of wood chip amendments on the revegetation performance of plant species on eroded marly terrains in a Mediterranean mountainous climate (Southern Alps, France)

    Science.gov (United States)

    Breton, Vincent; Crosaz, Yves; Rey, Freddy

    2016-04-01

    The establishment of plant species can limit soil erosion dynamics in degraded lands. In marly areas in the Southern French Alps, both harsh water erosion and drought conditions in summer due to the Mediterranean mountainous climate prevent the natural implementation and regeneration of vegetation. Soil fertility improvement is sometimes necessary. With the purpose of revegetating such areas, we aimed to evaluate the effects of wood chip amendments on the revegetation performance of different native or sub-spontaneous plant species. We conducted two experiments on steep slopes over three growing seasons (2012-2014). The first consisted of planting seedlings (10 species), and the second consisted of seeding (nine species including six used in the first experiment). First we noted that wood chips were able to remain in place even in steep slope conditions. The planting of seedlings showed both an impact of wood chip amendment and differences between species. A positive effect of wood chips was shown with overall improvement of plant survival (increasing by 11 % on average, by up to 50 % for some species). In the seeding experiment, no plants survived after three growing seasons. However, intermediate results for the first and second years showed a positive effect of wood chips on seedling emergence: seeds of four species only sprouted on wood chips, and for the five other species the average emergence rate increased by 50 %.

  14. Sensitivity of Greenland Ice Sheet surface mass balance to perturbations in sea surface temperature and sea ice cover: a study with the regional climate model MAR

    Science.gov (United States)

    Noël, B.; Fettweis, X.; van de Berg, W. J.; van den Broeke, M. R.; Erpicum, M.

    2014-10-01

    During recent summers (2007-2012), several surface melt records were broken over the Greenland Ice Sheet (GrIS). The extreme summer melt resulted in part from a persistent negative phase of the North Atlantic Oscillation (NAO), favoring warmer atmospheric conditions than normal over the GrIS. Simultaneously, large anomalies in sea ice cover (SIC) and sea surface temperature (SST) were observed in the North Atlantic, suggesting a possible connection. To assess the direct impact of 2007-2012 SIC and SST anomalies on GrIS surface mass balance (SMB), a set of sensitivity experiments was carried out with the regional climate model MAR forced by ERA-Interim. These simulations suggest that perturbations in SST and SIC in the seas surrounding Greenland do not considerably impact GrIS SMB, as a result of the katabatic wind blocking effect. These offshore-directed winds prevent oceanic near-surface air, influenced by SIC and SST anomalies, from penetrating far inland. Therefore, the ice sheet SMB response is restricted to coastal regions, where katabatic winds cease. A topic for further investigation is how anomalies in SIC and SST might have indirectly affected the surface melt by changing the general circulation in the North Atlantic region, hence favoring more frequent warm air advection towards the GrIS.

  15. Lakes on Mars

    CERN Document Server

    Cabrol, Nathalie A

    2014-01-01

    On Earth, lakes provide favorable environments for the development of life and its preservation as fossils. They are extremely sensitive to climate fluctuations and to conditions within their watersheds. As such, lakes are unique markers of the impact of environmental changes. Past and current missions have now demonstrated that water once flowed at the surface of Mars early in its history. Evidence of ancient ponding has been uncovered at scales ranging from a few kilometers to possibly that of the Arctic ocean. Whether life existed on Mars is still unknown; upcoming missions may find critic

  16. Comparison of "warm and wet" and "cold and icy" scenarios for early Mars in a 3D climate model

    CERN Document Server

    Wordsworth, Robin D; Pierrehumbert, Raymond T; Forget, Francois; Head, James W

    2015-01-01

    We use a 3D general circulation model to compare the primitive Martian hydrological cycle in "warm and wet" and "cold and icy" scenarios. In the warm and wet scenario, an anomalously high solar flux or intense greenhouse warming artificially added to the climate model are required to maintain warm conditions and an ice-free northern ocean. Precipitation shows strong surface variations, with high rates around Hellas basin and west of Tharsis but low rates around Margaritifer Sinus (where the observed valley network drainage density is nonetheless high). In the cold and icy scenario, snow migration is a function of both obliquity and surface pressure, and limited episodic melting is possible through combinations of seasonal, volcanic and impact forcing. At surface pressures above those required to avoid atmospheric collapse (~0.5 bar) and moderate to high obliquity, snow is transported to the equatorial highland regions where the concentration of valley networks is highest. Snow accumulation in the Aeolis quadr...

  17. Identification of Alteration Features in Basalts by Atomic Force Microscopy: New Approach for Understanding the Climate History of Mars.

    Science.gov (United States)

    Skiścim, M.; Gurgurewicz, J.; Mège, D.

    2014-12-01

    Studies on Martian meteorites, as well as the analysis of data obtained during space missions, indicate the presence of basalts on the Martian surface. Analysis of their alteration features may provide insights into the climate evolution and its local variations. In this work we consider Atomic Force Microscopy (AFM) as a tool to identify diagnostic alteration features on a basaltic surface. AFM is one of the most widely used tools for surface science and has already been introduced in space missions. Its advantages include, among others, low instrument weight and high resolution capability. It allows to observe objects in the nanoscale and analyze their topography and roughness. AFM can operate in ambient atmosphere and can be used for different, also non-conductive, materials. However, it has some significant limitations, e.g. it is not possible to determine the chemical composition directly. In order to assess the suitability of this method for analysis of basalt alteration it is necessary to complement AFM with other methods, in this case, Scanning Electron Microscopy (SEM). Basalt samples from arid cold (Udokan, Siberia) and arid hot (Ogaden, Ethiopia) environments, two of the possible Martian end-member paleo-environments, have been studied. Interesting places in the samples were marked with a diamond stylus for easy identification with AFM and SEM. Mineralogical analysis based on backscattered electron spectra (BSE) was carried out in selected areas of the samples. Structures examined by AFM were assigned to specific mineral phases; it is possible to perceive details of structures that may result from weathering. The study of rocks exposed to contrasted climatic conditions (arid cold and arid hot) aims at determining effect of temperature on the formation of these features. With the used experimental approach, the same area in a given sample can be studied both by SEM and AFM. The structure of minerals identified in the BSE can be located and observed at

  18. Mars Ice Age, Simulated

    Science.gov (United States)

    2003-01-01

    December 17, 2003This simulated view shows Mars as it might have appeared during the height of a possible ice age in geologically recent time.Of all Solar System planets, Mars has the climate most like that of Earth. Both are sensitive to small changes in orbit and tilt. During a period about 2.1 million to 400,000 years ago, increased tilt of Mars' rotational axis caused increased solar heating at the poles. A new study using observations from NASA's Mars Global Surveyor and Mars Odyssey orbiters concludes that this polar warming caused mobilization of water vapor and dust into the atmosphere, and buildup of a surface deposit of ice and dust down to about 30 degrees latitude in both hemispheres. That is the equivalent of the southern Unites States or Saudi Arabia on Earth. Mars has been in an interglacial period characterized by less axial tilt for about the last 300,000 years. The ice-rich surface deposit has been degrading in the latitude zone of 30 degrees to 60 degrees as water-ice returns to the poles.In this illustration prepared for the December 18, 2003, cover of the journal Nature, the simulated surface deposit is superposed on a topography map based on altitude measurements by Global Surveyor and images from NASA's Viking orbiters of the 1970s.Mars Global Surveyor and Mars Odyssey are managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, for the NASA Office of Space Science, Washington.

  19. The nature of Mars's surface hydration: converging views from satellite (MEX), surface (MSL) and meteorite (NWA 7034 / 7533 and co) observations.

    Science.gov (United States)

    Beck, P.; Pommerol, A.; Zanda, B.; Remusat, L.; Lorand, J. P.; Gopel, C. H.; Hewins, R.; Pont, S.; Lewin, E.; Quirico, E.; Schmitt, B.; Montes-Hernandez, G.; Garenne, A.; Bonal, L.; Proux, O.; Hazemann, J. L.; Chevrier, V.; Martín-Torres, J.; Zorzano, M. P.; Gasnault, O.; Maurice, S.; Wiens, R. C.

    2014-12-01

    Early infrared observations of the Martian surface have revealed the presence of a deep absorption between 2.6 and 3.5 µm usually referred to as the 3-µm band. Two non-exclusive explanations have been formulated to account for this 3-µm band. The first possibility is that it relates to the presence of some amount of adsorbed atmospheric water, water that would be exchangeable and could play a role in present day Mars water cycle. The alternative is that this absorption is due to an -OH or H2O bearing mineral component within the Martian dust, which would imply that water is involved at some stage of the dust production mechanism. Several lines of evidences seem to converge toward the second hypothesis. First, after 10 years of mapping of the martian surface with OMEGA (MEX), the lack of variation of the 3-µm feature with surface relative humidity suggests that the surface hydration does not exchange with the atmosphere. This is in agreement with laboratory adsorption experiments under Mars conditions. 
More recently the Mars Science Laboratory with unprecedented payload has provided some crucial constraints on the nature of surface hydration. The ChemCam instrument onboard MSL has detected hydrogen in dust and soil, and revealed the lack of variation of H concentration with surface humidity, including nighttime measurements. Also, evolved gas analysis by SAM of Gale crater soils shows that water is released at relatively high-temperature and suggest that -OH or H2O bearing phases are trapped in the amorphous component of soils. 
Finally, the exceptional "black beauty" meteorite might also provide clues to the nature of Mars's surface hydration. This Martian breccia shows elevated amount of water with respect to any other Martian meteorite. By studying the spectral properties of NWA 7533, we were able to show the presence of a 3-µm band and a small red-slope; this Martian breccia seems to contain a fine-oxidized-H-bearing component, possibly similar to that

  20. Validation of Two MODIS Aerosols Algorithms with SKYNET and Prospects for Future Climate Satellites Such as the GCOM-C/SGLI

    Directory of Open Access Journals (Sweden)

    Jules R. Dim

    2013-01-01

    Full Text Available Potential improvements of aerosols algorithms for future climate-oriented satellites such as the coming Global Change Observation Mission Climate/Second generation Global Imager (GCOM-C/SGLI are discussed based on a validation study of three years’ (2008–2010 daily aerosols properties, that is, the aerosol optical thickness (AOT and the Ångström exponent (AE retrieved from two MODIS algorithms. The ground-truth data used for this validation study are aerosols measurements from 3 SKYNET ground sites. The results obtained show a good agreement between the ground-truth data AOT and that of one of the satellites’ algorithms, then a systematic overestimation (around 0.2 by the other satellites’ algorithm. The examination of the AE shows a clear underestimation (by around 0.2–0.3 by both satellites’ algorithms. The uncertainties explaining these ground-satellites’ algorithms discrepancies are examined: the cloud contamination affects differently the aerosols properties (AOT and AE of both satellites’ algorithms due to the retrieval scale differences between these algorithms. The deviation of the real part of the refractive index values assumed by the satellites’ algorithms from that of the ground tends to decrease the accuracy of the AOT of both satellites’ algorithms. The asymmetry factor (AF of the ground tends to increase the AE ground-satellites discrepancies as well.

  1. Comparative analysis of land, marine, and satellite observations of methane in the lower Atmosphere in the Russian Arctic under conditions of climate change

    Science.gov (United States)

    Anisimov, O. A.; Kokorev, V. A.

    2015-12-01

    Land, marine, and satellite observations have been used to study changes in methane concentrations in the lower atmosphere during the warm months of the year (July through October) in Arctic regions having different potentials for methane production. The Atmospheric Infrared Sounder (AIRS) data for 2002-2013 are used to explore the interplay between local methane sources in the terrestrial region of the Eurasian Arctic and on the Arctic shelf over the warm period of the year. Linear trends in atmospheric methane concentrations over different Arctic regions are calculated, and a hypothesis of the relation of concentration variations to climatic parameters is tested. The combination of land, marine, and satellite observation is used to develop a conceptual model of the atmospheric methane field in the terrestrial part of the Russian Arctic and on the Arctic shelf. It is shown that the modern methane growth rate in the Arctic does not exceed the Northern Hemisphere mean. It is concluded that the methane emission in the Arctic has little effect on global climate compared to other factors.

  2. Temporal and spatial evaluation of satellite-based rainfall estimates across the complex topographical and climatic gradients of Chile

    Science.gov (United States)

    Zambrano-Bigiarini, Mauricio; Nauditt, Alexandra; Birkel, Christian; Verbist, Koen; Ribbe, Lars

    2017-03-01

    Accurate representation of the real spatio-temporal variability of catchment rainfall inputs is currently severely limited. Moreover, spatially interpolated catchment precipitation is subject to large uncertainties, particularly in developing countries and regions which are difficult to access. Recently, satellite-based rainfall estimates (SREs) provide an unprecedented opportunity for a wide range of hydrological applications, from water resources modelling to monitoring of extreme events such as droughts and floods.This study attempts to exhaustively evaluate - for the first time - the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-Adj, MSWEPv1.1, and PGFv3) over the complex topography and diverse climatic gradients of Chile. Different temporal scales (daily, monthly, seasonal, annual) are used in a point-to-pixel comparison between precipitation time series measured at 366 stations (from sea level to 4600 m a.s.l. in the Andean Plateau) and the corresponding grid cell of each SRE (rescaled to a 0.25° grid if necessary). The modified Kling-Gupta efficiency was used to identify possible sources of systematic errors in each SRE. In addition, five categorical indices (PC, POD, FAR, ETS, fBIAS) were used to assess the ability of each SRE to correctly identify different precipitation intensities.Results revealed that most SRE products performed better for the humid South (36.4-43.7° S) and Central Chile (32.18-36.4° S), in particular at low- and mid-elevation zones (0-1000 m a.s.l.) compared to the arid northern regions and the Far South. Seasonally, all products performed best during the wet seasons (autumn and winter; MAM-JJA) compared to summer (DJF) and spring (SON). In addition, all SREs were able to correctly identify the occurrence of no-rain events, but they presented a low skill in classifying precipitation intensities during rainy days. Overall, PGFv3 exhibited the best performance everywhere

  3. Reconstruction of the 1979–2006 Greenland ice sheet surface mass balance using the regional climate model MAR

    Directory of Open Access Journals (Sweden)

    X. Fettweis

    2007-10-01

    Full Text Available Results from a 28-year simulation (1979–2006 over the Greenland ice sheet (GrIS reveal an increase of solid precipitation (+0.4±2.5 km3 yr−2 and run-off (+7.9±3.3 km3 yr−2 of surface meltwater. The net effect of these competing factors is a significant Surface Mass Balance (SMB loss of −7.2±5.1 km3 yr−2. The contribution of changes in the net water vapour flux (+0.02±0.09 km3 yr−2 and rainfall (+0.2±0.2 km3 yr−2 to the SMB variability is negligible. The meltwater supply has increased because the GrIS surface has been warming up +2.4°C since 1979. Sensible heat flux, latent heat flux and net solar radiation have not varied significantly over the last three decades. However, the simulated downward infrared flux has increased by 9.3 W m−2 since 1979. The natural climate variability (e.g. the North Atlantic Oscillation does not explain these changes. The recent global warming, due to the greenhouse gas concentration increase induced by human activities, could be a cause of these changes. The doubling of surface meltwater flux into the ocean over the period 1979–2006 suggests that the overall ice sheet mass balance has been increasingly negative, given the likely meltwater-induced acceleration of outlet glaciers. This study suggests that increased melting overshadows over an increased accumulation in a warming scenario and that the GrIS is likely to keep losing mass in the future. An enduring GrIS melting will probably affect in the future an certain effect on the stability of the thermohaline circulation and the global sea level rise.

  4. Satellite Data Support for the ARM Climate Research Facility, 8/01/2009 - 7/31/2015

    Energy Technology Data Exchange (ETDEWEB)

    Minnis, Patrick [NASA Langley Research Center, Hampton, VA (United States); Khaiyer, Mandana M [Science Systems and Applications, Inc., Hampton, VA (United States)

    2015-10-06

    This report summarizes the support provided by NASA Langley Research for the DOE ARM Program in the form of cloud and radiation products derived from satellite imager data for the period between 8/01/09 through 7/31/15. Cloud properties such as cloud amount, height, and optical depth as well as outgoing longwave and shortwave broadband radiative fluxes were derived from geostationary and low-earth orbiting satellite imager radiance measurements for domains encompassing ARM permanent sites and field campaigns during the performance period. Datasets provided and documents produced are listed.

  5. Mars bevares

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Hendricks, Elbert

    2009-01-01

    2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen......2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen...

  6. Satellite Instrument Calibration for Measuring Global Climate Change. Report of a Workshop at the University of Maryland Inn and Conference Center, College Park, MD. , November 12-14, 2002

    Science.gov (United States)

    Ohring, G.; Wielicki, B.; Spencer, R.; Emery, B.; Datla, R.

    2004-01-01

    Measuring the small changes associated with long-term global climate change from space is a daunting task. To address these problems and recommend directions for improvements in satellite instrument calibration some 75 scientists, including researchers who develop and analyze long-term data sets from satellites, experts in the field of satellite instrument calibration, and physicists working on state of the art calibration sources and standards met November 12 - 14, 2002 and discussed the issues. The workshop defined the absolute accuracies and long-term stabilities of global climate data sets that are needed to detect expected trends, translated these data set accuracies and stabilities to required satellite instrument accuracies and stabilities, and evaluated the ability of current observing systems to meet these requirements. The workshop's recommendations include a set of basic axioms or overarching principles that must guide high quality climate observations in general, and a roadmap for improving satellite instrument characterization, calibration, inter-calibration, and associated activities to meet the challenge of measuring global climate change. It is also recommended that a follow-up workshop be conducted to discuss implementation of the roadmap developed at this workshop.

  7. Satellite Instrument Calibration for Measuring Global Climate Change. Report of a Workshop at the University of Maryland Inn and Conference Center, College Park, MD. , November 12-14, 2002

    Science.gov (United States)

    Ohring, G.; Wielicki, B.; Spencer, R.; Emery, B.; Datla, R.

    2004-01-01

    Measuring the small changes associated with long-term global climate change from space is a daunting task. To address these problems and recommend directions for improvements in satellite instrument calibration some 75 scientists, including researchers who develop and analyze long-term data sets from satellites, experts in the field of satellite instrument calibration, and physicists working on state of the art calibration sources and standards met November 12 - 14, 2002 and discussed the issues. The workshop defined the absolute accuracies and long-term stabilities of global climate data sets that are needed to detect expected trends, translated these data set accuracies and stabilities to required satellite instrument accuracies and stabilities, and evaluated the ability of current observing systems to meet these requirements. The workshop's recommendations include a set of basic axioms or overarching principles that must guide high quality climate observations in general, and a roadmap for improving satellite instrument characterization, calibration, inter-calibration, and associated activities to meet the challenge of measuring global climate change. It is also recommended that a follow-up workshop be conducted to discuss implementation of the roadmap developed at this workshop.

  8. Representativeness errors in comparing chemistry transport and chemistry climate models with satellite UV-Vis tropospheric column retrievals

    NARCIS (Netherlands)

    Boersma, K.F.; Vinken, G.C.M.; Eskes, H.J.

    2016-01-01

    Ultraviolet-visible (UV-Vis) satellite retrievals of trace gas columns of nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) are useful to test and improve models of atmospheric composition, for data assimilation, air quality hindcasting and forecasting, a

  9. The MARS2013 Mars analog mission.

    Science.gov (United States)

    Groemer, Gernot; Soucek, Alexander; Frischauf, Norbert; Stumptner, Willibald; Ragonig, Christoph; Sams, Sebastian; Bartenstein, Thomas; Häuplik-Meusburger, Sandra; Petrova, Polina; Evetts, Simon; Sivenesan, Chan; Bothe, Claudia; Boyd, Andrea; Dinkelaker, Aline; Dissertori, Markus; Fasching, David; Fischer, Monika; Föger, Daniel; Foresta, Luca; Fritsch, Lukas; Fuchs, Harald; Gautsch, Christoph; Gerard, Stephan; Goetzloff, Linda; Gołebiowska, Izabella; Gorur, Paavan; Groemer, Gerhard; Groll, Petra; Haider, Christian; Haider, Olivia; Hauth, Eva; Hauth, Stefan; Hettrich, Sebastian; Jais, Wolfgang; Jones, Natalie; Taj-Eddine, Kamal; Karl, Alexander; Kauerhoff, Tilo; Khan, Muhammad Shadab; Kjeldsen, Andreas; Klauck, Jan; Losiak, Anna; Luger, Markus; Luger, Thomas; Luger, Ulrich; McArthur, Jane; Moser, Linda; Neuner, Julia; Orgel, Csilla; Ori, Gian Gabriele; Paternesi, Roberta; Peschier, Jarno; Pfeil, Isabella; Prock, Silvia; Radinger, Josef; Ramirez, Barbara; Ramo, Wissam; Rampey, Mike; Sams, Arnold; Sams, Elisabeth; Sandu, Oana; Sans, Alejandra; Sansone, Petra; Scheer, Daniela; Schildhammer, Daniel; Scornet, Quentin; Sejkora, Nina; Stadler, Andrea; Stummer, Florian; Taraba, Michael; Tlustos, Reinhard; Toferer, Ernst; Turetschek, Thomas; Winter, Egon; Zanella-Kux, Katja

    2014-05-01

    We report on the MARS2013 mission, a 4-week Mars analog field test in the northern Sahara. Nineteen experiments were conducted by a field crew in Morocco under simulated martian surface exploration conditions, supervised by a Mission Support Center in Innsbruck, Austria. A Remote Science Support team analyzed field data in near real time, providing planning input for the management of a complex system of field assets; two advanced space suit simulators, four robotic vehicles, an emergency shelter, and a stationary sensor platform in a realistic work flow were coordinated by a Flight Control Team. A dedicated flight planning group, external control centers for rover tele-operations, and a biomedical monitoring team supported the field operations. A 10 min satellite communication delay and other limitations pertinent to human planetary surface activities were introduced. The fields of research for the experiments were geology, human factors, astrobiology, robotics, tele-science, exploration, and operations research. This paper provides an overview of the geological context and environmental conditions of the test site and the mission architecture, in particular the communication infrastructure emulating the signal travel time between Earth and Mars. We report on the operational work flows and the experiments conducted, including a deployable shelter prototype for multiple-day extravehicular activities and contingency situations.

  10. Integrating Dendrochronology, Climate and Satellite Remote Sensing to Better Understand Savanna Landscape Dynamics in the Okavango Delta, Botswana

    Directory of Open Access Journals (Sweden)

    Jane Southworth

    2013-11-01

    Full Text Available This research examines the integration and potential uses of linkages between climate dynamics, savanna vegetation and landscape level processes within a highly vulnerable region, both in terms of climate variability and social systems. We explore the combined applications of two time-series methodologies: (1 climate signals detected in tree ring growth, from published literature, chronologies from the International Tree-Ring Data Bank, and minimal preliminary field data; and (2 new primary production (NPP data of vegetation cover over time derived from remotely sensed analyses. Both time-series are related to the regional patterns of precipitation, the principle driver of plant growth in the area. The approach is temporally and spatially multiscalar and examines the relationships between vegetation cover, type and amount, and precipitation shifts. We review literature linking dendrochronology, climate, and remotely sensed imagery, and, in addition, provide unique preliminary analyses from a dry study site located on the outer limit of the Okavango Delta. The work demonstrates integration across the different data sources, to provide a more holistic view of landscape level processes occurring in the last 30-50 years. These results corroborate the water-limited nature of the region and the dominance of precipitation in controlling vegetation growth. We present this integrative analysis of vegetation and climate change, as a prospective approach to facilitate the development of long-term climate/vegetation change records across multiple scales.

  11. Non-linearity issues and multiple ionization satellites in the PIXE portion of spectra from the Mars alpha particle X-ray spectrometer

    Science.gov (United States)

    Campbell, John L.; Heirwegh, Christopher M.; Ganly, Brianna

    2016-09-01

    Spectra from the laboratory and flight versions of the Curiosity rover's alpha particle X-ray spectrometer were fitted with an in-house version of GUPIX, revealing departures from linear behavior of the energy-channel relationships in the low X-ray energy region where alpha particle PIXE is the dominant excitation mechanism. The apparent energy shifts for the lightest elements present were attributed in part to multiple ionization satellites and in part to issues within the detector and/or the pulse processing chain. No specific issue was identified, but the second of these options was considered to be the more probable. Approximate corrections were derived and then applied within the GUAPX code which is designed specifically for quantitative evaluation of APXS spectra. The quality of fit was significantly improved. The peak areas of the light elements Na, Mg, Al and Si were changed by only a few percent in most spectra. The changes for elements with higher atomic number were generally smaller, with a few exceptions. Overall, the percentage peak area changes are much smaller than the overall uncertainties in derived concentrations, which are largely attributable to the effects of rock heterogeneity. The magnitude of the satellite contributions suggests the need to incorporate these routinely in accelerator-based PIXE using helium beams.

  12. Dynamic Response of Satellite-Derived Vegetation Growth to Climate Change in the Three North Shelter Forest Region in China

    Directory of Open Access Journals (Sweden)

    Bin He

    2015-08-01

    Full Text Available Since the late 1970s, the Chinese government has initiated ecological restoration programs in the Three North Shelter Forest System Project (TNSFSP area. Whether accelerated climate change will help or hinder these efforts is still poorly understood. Using the updated and extended AVHRR NDVI3g dataset from 1982 to 2011 and corresponding climatic data, we investigated vegetation variations in response to climate change. The results showed that the overall state of vegetation in the study region has improved over the past three decades. Vegetation cover significantly decreased in 23.1% and significantly increased in 21.8% of the study area. An increase in all three main vegetation types (forest, grassland, and cropland was observed, but the trend was only statistically significant in cropland. In addition, bare and sparsely vegetated areas, mainly located in the western part of the study area, have significantly expanded since the early 2000s. A moisture condition analysis indicated that the study area experienced significant climate variations, with warm-wet conditions in the western region and warm-dry conditions in the eastern region. Correlation analysis showed that variations in the Normalized Difference Vegetation Index (NDVI were positively correlated with precipitation and negatively correlated with temperature. Ultimately, climate change influenced vegetation growth by controlling the availability of soil moisture. Further investigation suggested that the positive impacts of precipitation on NDVI have weakened in the study region, whereas the negative impacts from temperature have been enhanced in the eastern study area. However, over recent years, the negative temperature impacts have been converted to positive impacts in the western region. Considering the variations in the relationship between NDVI and climatic variables, the warm–dry climate in the eastern region is likely harmful to vegetation growth, whereas the warm

  13. Ice-rich (periglacial) vs icy (glacial) depressions in the Argyre region, Mars: a proposed cold-climate dichotomy of landforms

    Science.gov (United States)

    Soare, R. J.; Conway, S. J.; Gallagher, C.; Dohm, J. M.

    2017-01-01

    On Mars, so-called "scalloped depressions" are widely observed in Utopia Planitia (UP) and Malea Planum (MP). Typically, they are rimless, metres- to decametres-deep, incised sharply, tiered inwardly, polygonised and sometimes pitted. The depressions seemingly incise terrain that is icy and possibly thermokarstic, i.e. produced by the thermal destabilisation of the icy terrain. Agewise, the depressions are thought to be relatively youthful, originating in the Late Amazonian Epoch. Here, we report the presence of similar depressions in the Argyre region (AR) (30-60° S; 290-355° E). More importantly, we separate and differentiate these landforms into two groups: (ice-rich) periglacial depressions (Type-1); and, (icy) glacial depressions (Type-2a-c). This differentiation is presented to the Mars community for the first time. Based on a suite of morphological and geological characteristics synonymous with ice-complexes in the Lena Peninsula (eastern Russia) and the Tuktoyaktuk Coastlands (Northwest Territories, Canada), we propose that the Type-1 depressions are ice-rich periglacial basins that have undergone volatile depletion largely by sublimation and as the result of thermal destabilisation. In keeping with the terms and associated definitions derived of terrestrial periglacial-geomorphology, ice-rich refers to permanently frozen-ground in which ice lenses or segregation ice (collectively referenced as excess ice) have formed. We suggest that the depressions are the product of a multi-step, cold-climate geochronology: (1) Atmospheric precipitation and surface accumulation of an icy mantle during recent high obliquities. (2) Regional or local triple-point conditions and thaw/evaporation of the mantle, either by exogenic forcing, i.e. obliquity-driven rises of aerial and sub-aerial temperatures, or endogenic forcing, i.e. along Argyre impact-related basement structures. (3) Meltwater migration into the regolith, at least to the full depth of the depressions. (4

  14. Interactive 3D Mars Visualization

    Science.gov (United States)

    Powell, Mark W.

    2012-01-01

    The Interactive 3D Mars Visualization system provides high-performance, immersive visualization of satellite and surface vehicle imagery of Mars. The software can be used in mission operations to provide the most accurate position information for the Mars rovers to date. When integrated into the mission data pipeline, this system allows mission planners to view the location of the rover on Mars to 0.01-meter accuracy with respect to satellite imagery, with dynamic updates to incorporate the latest position information. Given this information so early in the planning process, rover drivers are able to plan more accurate drive activities for the rover than ever before, increasing the execution of science activities significantly. Scientifically, this 3D mapping information puts all of the science analyses to date into geologic context on a daily basis instead of weeks or months, as was the norm prior to this contribution. This allows the science planners to judge the efficacy of their previously executed science observations much more efficiently, and achieve greater science return as a result. The Interactive 3D Mars surface view is a Mars terrain browsing software interface that encompasses the entire region of exploration for a Mars surface exploration mission. The view is interactive, allowing the user to pan in any direction by clicking and dragging, or to zoom in or out by scrolling the mouse or touchpad. This set currently includes tools for selecting a point of interest, and a ruler tool for displaying the distance between and positions of two points of interest. The mapping information can be harvested and shared through ubiquitous online mapping tools like Google Mars, NASA WorldWind, and Worldwide Telescope.

  15. Using High Resolution Satellite Precipitation fields to Assess the Impacts of Climate Change on the Santa Cruz and San Pedro River Basins

    Science.gov (United States)

    Robles-Morua, A.; Vivoni, E.; Rivera-Fernandez, E. R.; Dominguez, F.; Meixner, T.

    2013-05-01

    Hydrologic modeling using high spatiotemporal resolution satellite precipitation products in the southwestern United States and northwest Mexico is important given the sparse nature of available rain gauges. In addition, the bimodal distribution of annual precipitation also presents a challenge as differential climate impacts during the winter and summer seasons are not currently well understood. In this work, we focus on hydrological comparisons using rainfall forcing from a satellite-based product, downscaled GCM precipitation estimates and available ground observations. The simulations are being conducted in the Santa Cruz and San Pedro river basins along the Arizona-Sonora border at high spatiotemporal resolutions (~100 m and ~1 hour). We use a distributed hydrologic model, known as the TIN-based Real-time Integrated Basin Simulator (tRIBS), to generate simulated hydrological fields under historical (1991-2000) and climate change (2031-2040) scenarios obtained from an application of the Weather Research and Forecast (WRF) model. Using the distributed model, we transform the meteorological scenarios at 10-km, hourly resolution into predictions of the annual water budget, seasonal land surface fluxes and individual hydrographs of flood and recharge events. We compare the model outputs and rainfall fields of the WRF products against the forcing from the North American Land Data Assimilation System (NLDAS) and available ground observations from the National Climatic Data Center (NCDC) and Arizona Meteorological Network (AZMET). For this contribution, we selected two full years in the historical period and in the future scenario that represent wet and dry conditions for each decade. Given the size of the two basins, we rely on a high performance computing platform and a parallel domain discretization with higher resolutions maintained at experimental catchments in each river basin. Model simulations utilize best-available data across the Arizona-Sonora border on

  16. ASSESSING THE IMPACTS OF CLIMATE CHANGE ON TERRESTRIAL ECOSYSTEMS IN BHAVANISAGAR RESERVOIR AND ITS SURROUNDINGS, USING MULTITEMPORAL SATELLITE DATA AND GIS TECHNIQUES

    Directory of Open Access Journals (Sweden)

    G. Balamurugan

    2012-09-01

    Full Text Available Despite the warnings against climate change since the early century, recent human activities are still geared towards enhancing them. Because of climate change coupled by other human activities, natural ecosystems are facing difficulties in coping with the impacts of climate change. The evaluation of the impact of climate change on ecosystems implies studying a multi-component system in which the complexity of links is high enough to present doing it as a whole. Because of this, it is a reasonable approach to study separately the behavior of each element, to be afterwards linked into a general conceptual model for ecosystems behavior. Moreover, in the case of largely regulated region, the main impacts of climatic change will be fluvial-related since those related to the catchment areas will be severely damped by river regulation and management policies. This fact implies that Terrestrial fringes may become the main frontier between the ecosystems and climatic change effects. This paper describes the potential impacts of warming temperatures and changing precipitation on vegetation, wildlife, land use/ land covers, and agricultural ecosystems across the Bhavanisagar Reservoir region centered on Coimbatore district, Tamilnadu. We examine a geographic area that captures much of Reservoir, including a complex mosaic of urbanization and agriculture surrounding the Bhavanisagar Reservoir. The comparative study of land cover and soil status are provided using space images with middle resolution. Multitemporal satellite data provide the capability for mapping and monitoring land cover and land use change, but require the development of accurate and repeatable techniques that can be extended to a broad range of environments and conditions. The Landsat TM and ETM+ and SRTM-DEM images are included in analysis. The unsupervised and supervised classifications are applied for determination of different types of land cover. The research present here has focus

  17. High Resolution Surface Science at Mars

    Science.gov (United States)

    Bailey, Zachary J.; Tamppari, Leslie K.; Lock, Robert E.; Sturm, Erick J.

    2013-01-01

    The proposed mission would place a 2.4 m telescope in orbit around Mars with two focal plane instruments to obtain the highest resolution images and spectral maps of the surface to date (3-10x better than current). This investigation would make major contributions to all of the Mars Program Goals: life, climate, geology and preparation for human presence.

  18. Meteorological satellite systems

    CERN Document Server

    Tan, Su-Yin

    2014-01-01

    “Meteorological Satellite Systems” is a primer on weather satellites and their Earth applications. This book reviews historic developments and recent technological advancements in GEO and polar orbiting meteorological satellites. It explores the evolution of these remote sensing technologies and their capabilities to monitor short- and long-term changes in weather patterns in response to climate change. Satellites developed by various countries, such as U.S. meteorological satellites, EUMETSAT, and Russian, Chinese, Japanese and Indian satellite platforms are reviewed. This book also discusses international efforts to coordinate meteorological remote sensing data collection and sharing. This title provides a ready and quick reference for information about meteorological satellites. It serves as a useful tool for a broad audience that includes students, academics, private consultants, engineers, scientists, and teachers.

  19. The CM SAF SSM/I-based total column water vapour climate data record: methods and evaluation against re-analyses and satellite

    Directory of Open Access Journals (Sweden)

    M. Schröder

    2012-09-01

    Full Text Available The "European Organisation for the Exploitation of Meteorological Satellites" (EUMETSAT Satellite Application Facility on Climate Monitoring (CM SAF aims at the provision and sound validation of well documented Climate Data Records (CDRs in sustained and operational environments. In this study, a total column water vapour (WVPA climatology from CM SAF is presented and inter-compared to water vapour data records from various data sources. Based on homogenised brightness temperatures from the Special Sensor Microwave Imager (SSM/I, a climatology of WVPA has been generated within the Hamburg Ocean-Atmosphere Fluxes and Parameters from Satellite (HOAPS framework. Within a research and operation transition activity the HOAPS data and operations capabilities have been successfully transferred to the CM SAF where the complete HOAPS data and processing schemes are hosted in an operational environment. An objective analysis for interpolation, kriging, has been developed and applied to the swath-based WVPA retrievals from the HOAPS data set. The resulting climatology consists of daily and monthly mean fields of WVPA over the global ice-free ocean. The temporal coverage ranges from July 1987 to August 2006. After a comparison to the precursor product the CM SAF SSM/I-based climatology has been comprehensively compared to different types of meteorological analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF-ERA40, ERA INTERIM and operational analyses and from the Japan Meteorological Agency (JMA-JRA. This inter-comparison shows an overall good agreement between the climatology and the analyses, with daily absolute biases generally smaller than 2 kg m−2. The absolute bias to JRA and ERA INTERIM is typically smaller than 0.5 kg m−2. For the period 1991–2006, the root mean square error (RMSE to both reanalysis is approximately 2 kg m−2. As SSM/I WVPA and radiances are assimilated in JMA and all

  20. The CM SAF SSM/I-based total column water vapour climate data record: methods and evaluation against re-analyses and satellite

    Directory of Open Access Journals (Sweden)

    M. Schröder

    2013-03-01

    Full Text Available The European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT Satellite Application Facility on Climate Monitoring (CM SAF aims at the provision and sound validation of well documented Climate Data Records (CDRs in sustained and operational environments. In this study, a total column water vapour path (WVPA climatology from CM SAF is presented and inter-compared to water vapour data records from various data sources. Based on homogenised brightness temperatures from the Special Sensor Microwave Imager (SSM/I, a climatology of WVPA has been generated within the Hamburg Ocean–Atmosphere Fluxes and Parameters from Satellite (HOAPS framework. Within a research and operation transition activity the HOAPS data and operation capabilities have been successfully transferred to the CM SAF where the complete HOAPS data and processing schemes are hosted in an operational environment. An objective analysis for interpolation, namely kriging, has been applied to the swath-based WVPA retrievals from the HOAPS data set. The resulting climatology consists of daily and monthly mean fields of WVPA over the global ice-free ocean. The temporal coverage ranges from July 1987 to August 2006. After a comparison to the precursor product the CM SAF SSM/I-based climatology has been comprehensively compared to different types of meteorological analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF-ERA40, ERA INTERIM and operational analyses and from the Japan Meteorological Agency (JMA–JRA. This inter-comparison shows an overall good agreement between the climatology and the analyses, with daily absolute biases generally smaller than 2 kg m−2. The absolute value of the bias to JRA and ERA INTERIM is typically smaller than 0.5 kg m−2. For the period 1991–2006, the root mean square error (RMSE for both reanalyses is approximately 2 kg m−2. As SSM/I WVPA and radiances are assimilated into JMA and all ECMWF analyses and

  1. Assessing ecosystem response to multiple disturbances and climate change in South Africa using ground- and satellite-based measurements and model

    Science.gov (United States)

    Kutsch, W. L.; Falge, E. M.; Brümmer, C.; Mukwashi, K.; Schmullius, C.; Hüttich, C.; Odipo, V.; Scholes, R. J.; Mudau, A.; Midgley, G.; Stevens, N.; Hickler, T.; Scheiter, S.; Martens, C.; Twine, W.; Iiyambo, T.; Bradshaw, K.; Lück, W.; Lenfers, U.; Thiel-Clemen, T.; du Toit, J.

    2015-12-01

    Sub-Saharan Africa currently experiences rapidly growing human population, intrinsically tied to substantial changes in land use on shrubland, savanna and mixed woodland ecosystems due to over-exploitation. Significant conversions driving degradation, affecting fire frequency and water availability, and fueling climate change are expected to increase in the immediate future. However, measured data of greenhouse gas emissions as affected by land use change are scarce to entirely lacking from this region. The project 'Adaptive Resilience of Southern African Ecosystems' (ARS AfricaE) conducts research and develops scenarios of ecosystem development under climate change, for management support in conservation or for planning rural area development. This will be achieved by (1) creation of a network of research clusters (paired sites with natural and altered vegetation) along an aridity gradient in South Africa for ground-based micrometeorological in-situ measurements of energy and matter fluxes, (2) linking biogeochemical functions with ecosystem structure, and eco-physiological properties, (3) description of ecosystem disturbance (and recovery) in terms of ecosystem function such as carbon balance components and water use efficiency, (4) set-up of individual-based models to predict ecosystem dynamics under (post) disturbance managements, (5) combination with long-term landscape dynamic information derived from remote sensing and aerial photography, and (6) development of sustainable management strategies for disturbed ecosystems and land use change. Emphasis is given on validation (by a suite of field measurements) of estimates obtained from eddy covariance, model approaches and satellite derivations.

  2. Mars Pathfinder

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    First of NASA's Discovery missions. Launched in December 1996 and arrived at Mars on 4 July 1997. Mainly intended as a technology demonstration mission. Used airbags to cushion the landing on Mars. The Carl Sagan Memorial station returned images of an ancient flood plain in Ares Vallis. The 10 kg Sojourner rover used an x-ray spectrometer to study the composition of rocks and travelled about 100 ...

  3. Exploring Mars

    Science.gov (United States)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  4. The Geologic Evidence for a Warm and Wet Early Mars

    Science.gov (United States)

    Craddock, R. A.; Irwin, R. P.; Howard, A. D.; Morgan, A. M.

    2017-10-01

    The geologic evidence supporting a warm and wet climate on early Mars is presented. The case against an "icy highlands" scenario is also made. Climate models are converging to a solution, but any theoretical data must explain the empirical data.

  5. An evaluation of uncertainty in the aerosol optical properties as represented by satellites and an ensemble of chemistry-climate coupled models over Europe

    Science.gov (United States)

    Palacios-Peña, Laura; Baró, Rocío; Jiménez-Guerrero, Pedro

    2016-04-01

    different wavelengths. Regarding the uncertainty in satellite representation of AOD, MODIS appears to have the best agreement with AERONET observations when compared to other satellite AOD observations. Focusing on the comparison between model output and MODIS and AERONET, results indicate a general slight improvement of AOD in the case of including the aerosol radiative effects in the model and a slight worsening for the Angström exponent for some stations and regions. Regarding the correlation coefficient, both episodes show similar values of this metric, which are higher for AOD. Generally, for the Angström exponent, models tend to underestimate the variability of this variable. Despite this , the improvement in the representation by on-line coupled chemistry-climate models of AOD reflected here may be of essential importance for a better description of aerosol-radiation-cloud interactions in regional climate models. On the other hand, the differences found between remote sensing sensors (which is of the same order of magnitude as the differences between the different members of the model ensemble) point out the uncertainty in the measurements and observations that have to be taken into account when the models are evaluated. Acknowledgments: the funding from REPAIR-CGL2014-59677-R projects (Spanish Ministry of Economy and Innovation, funded by the FEDER programme of the European Union). Special thanks to the EuMetChem COST ACTION ES1004.

  6. Validation of the regional climate model MAR over the CORDEX Africa domain and comparison with other regional models using unpublished data set

    Science.gov (United States)

    Prignon, Maxime; Agosta, Cécile; Kittel, Christoph; Fettweis, Xavier; Michel, Erpicum

    2016-04-01

    In the framework of the CORDEX project, we have applied the regional model MAR over the Africa domain at a resolution of 50 km. ERA-Interim and NCEP-NCAR reanalysis have been used as 6 hourly forcing at the MAR boundaries over 1950-2015. While MAR was already been validated over the West Africa, it is the first time that MAR simulations are carried out at the scale of the whole continent. Unpublished daily measurements, covering the Sahel and more areas up South, with a large set of variables, are used as validation of MAR, other CORDEX-Africa RCMs and both reanalyses. Comparisons with the CRU and the ECA&D databases are also performed. The unpublished daily data set covers the period 1884-2006 and comes from 1460 stations. The measured variables are wind, evapotranspiration, relative humidity, insolation, rain, surface pressure, temperature, vapour pressure and visibility. It covers 23 countries: Algeria, Benin, Burkina, Canary Islands, Cap Verde, Central Africa, Chad, Congo, Ivory Coast, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Mali, Mauritania, Morocco, Niger, Nigeria, Senegal, Sudan and Togo.

  7. The significance of cloud-radiative forcing to the general circulation on climate time scales - A satellite interpretation

    Science.gov (United States)

    Sohn, Byung-Ju; Smith, Eric A.

    1992-01-01

    This paper focuses on the role of cloud- and surface-atmosphere forcing on the net radiation balance and their potential impact on the general circulation at climate time scales. The globally averaged cloud-forcing estimates and cloud sensitivity values taken from various recent studies are summarized. It is shown that the net radiative heating over the tropics is principally due to high clouds, while the net cooling in mid- and high latitudes is dominated by low and middle clouds.

  8. Dust aerosol impact on North Africa climate: a GCM investigation of aerosol-cloud-radiation interactions using A-Train satellite data

    Directory of Open Access Journals (Sweden)

    Y. Gu

    2012-02-01

    Full Text Available The climatic effects of dust aerosols in North Africa have been investigated using the atmospheric general circulation model (AGCM developed at the University of California, Los Angeles (UCLA. The model includes an efficient and physically based radiation parameterization scheme developed specifically for application to clouds and aerosols. Parameterization of the effective ice particle size in association with the aerosol first indirect effect based on ice cloud and aerosol data retrieved from A-Train satellite observations have been employed in climate model simulations. Offline simulations reveal that the direct solar, IR, and net forcings by dust aerosols at the top of the atmosphere (TOA generally increase with increasing aerosol optical depth. When the dust semi-direct effect is included with the presence of ice clouds, positive IR radiative forcing is enhanced since ice clouds trap substantial IR radiation, while the positive solar forcing with dust aerosols alone has been changed to negative values due to the strong reflection of solar radiation by clouds, indicating that cloud forcing associated with aerosol semi-direct effect could exceed direct aerosol forcing. With the aerosol first indirect effect, the net cloud forcing is generally reduced in the case for an ice water path (IWP larger than 20 g m−2. The magnitude of the reduction increases with IWP.

    AGCM simulations show that the reduced ice crystal mean effective size due to the aerosol first indirect effect results in less OLR and net solar flux at TOA over the cloudy area of the North Africa region because ice clouds with smaller size trap more IR radiation and reflect more solar radiation. The precipitation in the same area, however, increases due to the aerosol indirect effect on ice clouds, corresponding to the enhanced convection as indicated by reduced OLR. Adding the aerosol direct effect into the model simulation reduces the precipitation in the

  9. Methods of satellite oceanography

    Science.gov (United States)

    Stewart, R. H.

    1985-01-01

    The theoretical basis for remote sensing measurements of climate and ocean dynamics is examined. Consideration is given to: the absorption of electromagnetic radiation in the atmosphere; scattering in the atmosphere; and satellite observations using visible light. Consideration is also given to: the theory of radio scatter from the sea; scatter of centimeter waves from the sea; and the theory of operation of synthetic aperture radars. Additional topics include: the coordinate systems of satellite orbits for oceanographic remote sensing applications; the operating features of the major U.S. satellite systems for viewing the ocean; and satellite altimetry.

  10. Assessment of regional climatic changes in the Eastern Himalayan region: a study using multi-satellite remote sensing data sets.

    Science.gov (United States)

    Agrawal, Anubha; Sharma, Anu Rani; Tayal, Shresth

    2014-10-01

    In this study, an attempt has been made to capture the sensitivity of a mountainous region to elevation-dependent warming and the response of a glacier-laden surface to increasing greenhouse gases (GHGs) and aerosol concentration. Some of the changes Sikkim has undergone due to urban sprawl are as follows: an increase of ~0.7 ± 0.46 °C temperature in the past 40 years at an altitude of 5.5 km; a 2.21 km(2)/year rate of loss of glacierised area in the past 33 years; an increase in absorbed longwave radiation (6 ± 2.41 W/m(2)); an increase in heat fluxes (2 ± 0.97 W/m(2)); a decrease in albedo during the last 30 years; an increase in the concentrations of carbon dioxide (4.42%), methane (0.61%), ozone (0.67%) and black carbon column optical depth (7.19%); a decrease in carbon monoxide (2.61%) and an increase in aerosol optical depth (19.16%) during the last decade; a decrease in precipitation, water yield, discharge and groundwater; and an increase in evapotranspiration during 1971-2005. Detection of three climate signals (1976, 1997 and 2005) in the entire analysis is the quantification of the fact that the climate of Sikkim is moving away from its inter-annual variability. An increase in temperature (0.23 °C/decade) at higher altitude (~5.5 km), suppression of precipitation, decreasing water availability and rapid loss of glacierised area are the evidences of the fact that air pollution is playing a significant role in bringing about regional climatic changes in Sikkim. In this study, change detection method has been used for the first time for the estimation of change in a glacierised area of the region.

  11. Cloud attenuation studies of the six major climatic zones of Africa for Ka and V satellite system design

    Directory of Open Access Journals (Sweden)

    Temidayo Victor Omotosho

    2014-01-01

    Full Text Available Normal 0 false false false EN-GB X-NONE X-NONE Cloud cover statistics, cloud base and top height, cloud temperature, frequency of precipitation, freezing height, total cloud liquid water content (TCLWC and cloud attenuation data have been obtained for the six major climatic zones of Africa. The present results reveal a strong positive correlation between the monthly distribution of low cloud cover, cloud top height, cloud temperature, and frequency of precipitation in the six zones. The cumulative distribution of the TCLWC derived from radiosonde measurement in each climatic zone shows a departure from the TCLWC recommended by the ITU Study Group 3 data, with an exceedance percentage difference of 32% to 90% occurring 0.01% to 10% of the time. The underestimation of the TCLWC is greatest in the tropical rain forest. A comparison of the cloud attenuation cumulative distribution in the Ka and V bands reveals that the International Telecommunication Union – Region (ITU-R is an intergovernmental organization that develops rain model based on collected data around the world. This model underestimates the cloud attenuation in all of the six climatic zones by 2.0 dB and 4.7 dB for the arid Sahara desert, 1.3 dB and 3.0 dB in semi-arid North Africa, 1.3 dB and 1.5 dB in savannah North Africa, 2.0 dB and 3.6 dB in the tropical rain forest, 1.3 dB and 2.9 dB in savannah South Africa and 0.9 dB and 2.6 dB in semi-arid South Africa, respectively, at 30 and 50 GHz. Overall, the cloud attenuation in the tropical rain-forest zone is very high because of the high annual total cloud cover (98%, high annual frequency of precipitation (4.5, low annual clear sky amount (8%, high cloud depth (10,937 m, high 0°C isotherm height (4.7 km, high TCLWC (4.0 kg/m2 at 0.01% and low seasonal cloud base height (356 m.

  12. Space Systems Failures Disasters and Rescues of Satellites, Rockets and Space Probes

    CERN Document Server

    Harland, David M

    2005-01-01

    In the 1960s and 1970s deep space missions were dispatched in pairs in case one was lost in launch or failed during its journey. Following the triumphs of the Viking landings on Mars in 1976 and both Voyagers spacecraft successfully surveying the outer giant planets of the Solar System, it was decided by NASA to cut costs and send out just a single probe. Although Magellan successfully mapped Venus by radar, it suffered from problems during the flight. Then came the loss of Mars Observer, whose engine exploded as it was preparing to enter Mars’ orbit because it was using technology designed for Earth’s satellites and the engine was not suited to spending several months in space. Later came the high-profile losses of Mars Climate Observer and Mars Polar Lander - a consequence of the faster, better, cheaper philosophy introduced by Dan Goldin in 1993. Even the highly successful Galileo mission suffered a major setback when its high-gain antenna (also based on satellite mission suffered a major setback when ...

  13. Effect of Terrestrial and Marine Organic Aerosol on Regional and Global Climate: Model Development, Application, and Verification with Satellite Data

    Energy Technology Data Exchange (ETDEWEB)

    Meskhidze, Nicholas; Zhang, Yang; Kamykowski, Daniel

    2012-03-28

    In this DOE project the improvements to parameterization of marine primary organic matter (POM) emissions, hygroscopic properties of marine POM, marine isoprene derived secondary organic aerosol (SOA) emissions, surfactant effects, new cloud droplet activation parameterization have been implemented into Community Atmosphere Model (CAM 5.0), with a seven mode aerosol module from the Pacific Northwest National Laboratory (PNNL)'s Modal Aerosol Model (MAM7). The effects of marine aerosols derived from sea spray and ocean emitted biogenic volatile organic compounds (BVOCs) on microphysical properties of clouds were explored by conducting 10 year CAM5.0-MAM7 model simulations at a grid resolution 1.9° by 2.5° with 30 vertical layers. Model-predicted relationship between ocean physical and biological systems and the abundance of CCN in remote marine atmosphere was compared to data from the A-Train satellites (MODIS, CALIPSO, AMSR-E). Model simulations show that on average, primary and secondary organic aerosol emissions from the ocean can yield up to 20% increase in Cloud Condensation Nuclei (CCN) at 0.2% Supersaturation, and up to 5% increases in droplet number concentration of global maritime shallow clouds. Marine organics were treated as internally or externally mixed with sea salt. Changes associated with cloud properties reduced (absolute value) the model-predicted short wave cloud forcing from -1.35 Wm-2 to -0.25 Wm-2. By using different emission scenarios, and droplet activation parameterizations, this study suggests that addition of marine primary aerosols and biologically generated reactive gases makes an important difference in radiative forcing assessments. All baseline and sensitivity simulations for 2001 and 2050 using global-through-urban WRF/Chem (GU-WRF) were completed. The main objective of these simulations was to evaluate the capability of GU-WRF for an accurate representation of the global atmosphere by exploring the most accurate

  14. EPA To Announce 2016 Climate Leadership Awards/ Mars, Microsoft, Ingersoll Rand, and Calif. Department of Water Resources to Earn Organizational Leadership Awards, Among 17 Awardees Recognized for Climate Action

    Science.gov (United States)

    WASHINGTON - Today, U.S. Environmental Protection Agency Administrator Gina McCarthy will recognize organizations from around the country at the Climate Leadership Awards for their leadership and innovation in helping fight climate change. Winners a

  15. Production of satellite-derived aerosol climate data records: current status of the ESA Aerosol_cci project

    Science.gov (United States)

    de Leeuw, Gerrit; Holzer-Popp, Thomas; Pinnock, Simon

    2015-04-01

    and the Aerosol_cci team Within the ESA Climate Change Initiative (CCI) project Aerosol_cci (Phase 1: 2010 -2014; Phase 2: 2014-2017) intensive work has been conducted to improve algorithms for the retrieval of aerosol information from European sensors ATSR (3 algorithms), PARASOL, MERIS (3 algorithms), synergetic AATSR/SCIAMACHY, OMI and GOMOS. Whereas OMI and GOMOS were used to derive absorbing aerosol index and stratospheric extinction profiles, respectively, Aerosol Optical Depth (AOD) and Ångström coefficient were retrieved from the other sensors. The cooperation between the project partners, including both the retrieval teams and independent validation teams, has resulted in a strong improvement of most algorithms. In particular the AATSR retrieved AOD is qualitatively similar to that from MODIS, usually taken as the standard, MISR and SeaWiFS. This conclusion has been reached form several different ways of validation of the L2 and L3 products, using AERONET sun photometer data as the common ground-truth for the application of both 'traditional' statistical techniques and a 'scoring' technique using spatial and temporal correlations. Quantitatively, the limited AATSR swath width of 500km results in a smaller amount of data. Nevertheless, the assimilation of AATSR-retrieved AOD, together with MODIS data, contributes to improving the in the ECMWF climate model results. In addition to the multi-spectral AOD, and thus the Ångström Exponent, also a per-pixel uncertainty is provided and validated. By the end of Aerosol_cci Phase 1 the ATSR algorithms have been applied to both ATSR-2 and AATSR resulting in an AOD time series of 17 years. In phase 2 this work is continued with a focus on the further improvement of the ATSR algorithms as well as those for the other instruments and algorithms, mentioned above, which in phase 1 were considered less mature. The first efforts are on the further characterization of the uncertainties and on better understanding of the

  16. Mar Capeans

    CERN Multimedia

    2017-01-01

    Mar Capeans, CERN researcher, answers the question to "What can we do in the world of sciences and innovation to make visible the invisible?". This piece belongs to a series of videos made by the Spanish Aquae Foundation, a supporter of the CERN & Society Foundation.

  17. Mar adentro

    OpenAIRE

    Florián Guerrero, Mayra

    2014-01-01

    La bravura del mar destruyó primero las canchas de fútbol, luego se tragó casas y finalmente las playas. El otrora balneario exclusivo de Buenos Aires, donde se fundó el famoso restaurant Morillas en los años 40, es ahora un tímido recuerdo en medio del chocar incesante de las olas.

  18. A long-term record of blended satellite and in situ sea-surface temperature for climate monitoring, modeling and environmental studies

    Science.gov (United States)

    Banzon, Viva; Smith, Thomas M.; Chin, Toshio Mike; Liu, Chunying; Hankins, William

    2016-04-01

    This paper describes a blended sea-surface temperature (SST) data set that is part of the National Oceanic and Atmospheric Administration (NOAA) Climate Data Record (CDR) program product suite. Using optimum interpolation (OI), in situ and satellite observations are combined on a daily and 0.25° spatial grid to form an SST analysis, i.e., a spatially complete field. A large-scale bias adjustment of the input infrared SSTs is made using buoy and ship observations as a reference. This is particularly important for the time periods when volcanic aerosols from the El Chichón and Mt. Pinatubo eruptions are widespread globally. The main source of SSTs is the Advanced Very High Resolution Radiometer (AVHRR), available from late 1981 to the present, which is also the temporal span of this CDR. The input and processing choices made to ensure a consistent data set that meets the CDR requirements are summarized. A brief history and an explanation of the forward production schedule for the preliminary and science-quality final product are also provided. The data set is produced and archived at the newly formed National Centers for Environmental Information (NCEI) in Network Common Data Form (netCDF) at doi:10.7289/V5SQ8XB5.

  19. A GIS-based assessment of the suitability of SCIAMACHY satellite sensor measurements for estimating reliable CO concentrations in a low-latitude climate.

    Science.gov (United States)

    Fagbeja, Mofoluso A; Hill, Jennifer L; Chatterton, Tim J; Longhurst, James W S

    2015-02-01

    An assessment of the reliability of the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) satellite sensor measurements to interpolate tropospheric concentrations of carbon monoxide considering the low-latitude climate of the Niger Delta region in Nigeria was conducted. Monthly SCIAMACHY carbon monoxide (CO) column measurements from January 2,003 to December 2005 were interpolated using ordinary kriging technique. The spatio-temporal variations observed in the reliability were based on proximity to the Atlantic Ocean, seasonal variations in the intensities of rainfall and relative humidity, the presence of dust particles from the Sahara desert, industrialization in Southwest Nigeria and biomass burning during the dry season in Northern Nigeria. Spatial reliabilities of 74 and 42 % are observed for the inland and coastal areas, respectively. Temporally, average reliability of 61 and 55 % occur during the dry and wet seasons, respectively. Reliability in the inland and coastal areas was 72 and 38 % during the wet season, and 75 and 46 % during the dry season, respectively. Based on the results, the WFM-DOAS SCIAMACHY CO data product used for this study is therefore relevant in the assessment of CO concentrations in developing countries within the low latitudes that could not afford monitoring infrastructure due to the required high costs. Although the SCIAMACHY sensor is no longer available, it provided cost-effective, reliable and accessible data that could support air quality assessment in developing countries.

  20. Detecting Ecosystem Performance Anomalies for Land Management in the Upper Colorado River Basin Using Satellite Observations, Climate Data, and Ecosystem Models

    Directory of Open Access Journals (Sweden)

    Bruce K. Wylie

    2010-07-01

    Full Text Available This study identifies areas with ecosystem performance anomalies (EPA within the Upper Colorado River Basin (UCRB during 2005–2007 using satellite observations, climate data, and ecosystem models. The final EPA maps with 250-m spatial resolution were categorized as normal performance, underperformance, and overperformance (observed performance relative to weather-based predictions at the 90% level of confidence. The EPA maps were validated using “percentage of bare soil” ground observations. The validation results at locations with comparable site potential showed that regions identified as persistently underperforming (overperforming tended to have a higher (lower percentage of bare soil, suggesting that our preliminary EPA maps are reliable and agree with ground-based observations. The 3-year (2005–2007 persistent EPA map from this study provides the first quantitative evaluation of ecosystem performance anomalies within the UCRB and will help the Bureau of Land Management (BLM identify potentially degraded lands. Results from this study can be used as a prototype by BLM and other land managers for making optimal land management decisions.

  1. Mapping the northern plains of Mars: origins, evolution and response to climate change - a new overview of recent ice-related landforms in Utopia Planitia

    Science.gov (United States)

    Séjourné, A.; Costard, F.; Losiak, A.; Swirad, Z. M.; Balme, M. R.; Conway, S. J.; Gallagher, C.; Hauber, E.; Johnsson, A. E.; Kereszturi, A.; Orgel, C.; Platz, T.; Ramsdale, J. D.; Reiss, D.; Skinner, J. A., Jr.; Van Gasselt, S.

    2015-10-01

    An International Space Science Institute (ISSI) team project has been convened to study ice-related landforms in targeted areas in the northern plain of Mars: Acidalia Planitia, Arcadia Planitia, and Utopia Planitia. Here, over western Utopia Planitia, ice-related landforms were identified and recorded in a sub-grid square. The end result of the mapping is a "raster" showing the distribution of thevarious different types of landforms across the whole strip providing a digital geomorph ological map (Fig. 1).

  2. Hygroscopic Salts on Mars

    Science.gov (United States)

    Melchiorri, R.; Davila, A. F.; Chittenden, J.; Haberle, R. M.

    2008-12-01

    We present preliminary results on the influence of a salt-rich regolith in the water cycle of Mars. Global climate modeling shows that the relative humidity on the Martian surface often reaches values above the deliquescence point of salts that are common components of the regolith. At the deliquescence point, these salts will absorb atmospheric water vapor and form a saturated, transient liquid solution that is stable under a range of temperatures. If atmospheric temperatures fall below the eutectic point of the solution, the later will freeze in the pore space of the regolith, thereby resulting in a net transport of water from the vapor phase in the atmosphere, to the solid state in the regolith. This simple model partially accounts for some the distribution of water on the Martian surface as revealed by Mars Odyssey, in particular, we find that: even though the Cl and surface water distributions detected by HEND/ODYSSEY are highly correlated, salt deliquescence under the the present atmospheric conditions does not explain the overall distribution of water in the near surface regolith. However deliquescence of salt-rich soils could be an important contributor to the distribution of water in the regolith at high obliquity. In that scenario the water in the near-surface regolith would be the remnant of high obliquity conditions salt deliquescence is still active in different regions on Mars today, and it should be introduced as a parameter in the modern GCMs as a new ground/atmosphere interaction

  3. NOAA Climate Data Record (CDR) of Gridded Satellite Data from ISCCP B1 (GridSat-B1) Infrared Channel Brightness Temperature, Version 2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Gridded Satellite (GridSat-B1) data provides a uniform set of quality controlled geostationary satellite observations for the visible, infrared window and...

  4. Climate Observations from Space

    Science.gov (United States)

    Briggs, Stephen

    2016-07-01

    The latest Global Climate Observing System (GCOS) Status Report on global climate observations, delivered to the UNFCCC COP21 in November 2016, showed how satellite data are critical for observations relating to climate. Of the 50 Essential Climate Variables (ECVs) identified by GCOS as necessary for understanding climate change, about half are derived only from satellite data while half of the remainder have a significant input from satellites. Hence data from Earth observing satellite systems are now a fundamental requirement for understanding the climate system and for managing the consequences of climate change. Following the Paris Agreement of COP21 this need is only greater. Not only will satellites have to continue to provide data for modelling and predicting climate change but also for a much wider range of actions relating to climate. These include better information on loss and damage, resilience, improved adaptation to change, and on mitigation including information on greenhouse gas emissions. In addition there is an emerging need for indicators of the risks associated with future climate change which need to be better quantified, allowing policy makers both to understand what decisions need to be taken, and to see the consequences of their actions. The presentation will set out some of the ways in which satellite data are important in all aspects of understanding, managing and predicting climate change and how they may be used to support future decisions by those responsible for policy related to managing climate change and its consequences.

  5. Satellite-Based Monitoring of Decadal Soil Salinization and Climate Effects in a Semi-arid Region of China

    Institute of Scientific and Technical Information of China (English)

    WANG Hesong; JIA Gensuo

    2012-01-01

    Soil salinization is a common phenomenon that affects both the environment and the socio-economy in arid and semi-arid regions; it is also an important aspect of land cover change.In this study,we integrated multi-sensor remote sensing data with a field survey to analyze processes of soil salinization in a semi-arid area in China from 1979 to 2009. Generally,the area of salt-affected soils increased by 0.28% per year with remarkable acceleration from 1999 to 2009 (0.42% increase per year).In contrast,the area of surface water bodies showed a decreasing trend (-0.08% per year) in the same period.Decreases in precipitation and increases in aridity due to annual (especially summer) warming provided a favorable condition for soil salinization. The relatively flat terrain favored waterlogging at the surface,and continuous drought facilitated upward movement of soil water and accumulation of surface saline and calcium. Meanwhile,land-use practices also played a crucial role in accelerating soil salinization.The conversion to cropland from natural vegetation greatly increased the demand for groundwater irrigation and aggravated the process of soil salinization.Furthermore,there are potential feedbacks of soil salinization to regional climate.The salinization of soils can limit the efficiency of plant water use as well as photosynthesis; therefore,it reduces the amount of carbon sequestrated by terrestrial ecosystem.Soil salinization also reduces the absorbed solar radiation by increasing land surface albedo.Such conversions of land cover significantly change the energy and water balance between land and atmosphere.

  6. Dust aerosol impact on North Africa climate: a GCM investigation of aerosol-cloud-radiation interactions using A-Train satellite data

    Directory of Open Access Journals (Sweden)

    Y. Gu

    2011-12-01

    Full Text Available The climatic effects of dust aerosols in North Africa have been investigated using the atmospheric general circulation model (AGCM developed at the University of California, Los Angeles (UCLA. The model includes an efficient and physically based radiation parameterization scheme developed specifically for application to clouds and aerosols. Parameterization of the effective ice particle size in association with the aerosol first indirect effect based on ice cloud and aerosol data retrieved from A-Train satellite observations have been employed in climate model simulations. Offline simulations reveal that the direct solar, IR, and net forcings by dust aerosols at the top of the atmosphere (TOA generally increase with increasing aerosol optical depth (AOD. When the dust semi-direct effect is included with the presence of ice clouds, positive IR radiative forcing is enhanced since ice clouds trap substantial IR radiation, while the positive solar forcing with dust aerosols alone has been changed to negative values due to the strong reflection of solar radiation by clouds, indicating that cloud forcing associated with aerosol semi-direct effect could exceed direct aerosol forcing. With the aerosol first indirect effect, the net cloud forcing is generally reduced for an ice water path (IWP larger than 20 g m−2. The magnitude of the reduction increases with IWP.

    AGCM simulations show that the reduced ice crystal mean effective size due to the aerosol first indirect effect results in less OLR and net solar flux at the top of the atmosphere over the cloudy area of the North Africa region because ice clouds with smaller size trap more IR radiation and reflect more solar radiation. The precipitation in the same area, however, increases due to the aerosol indirect effect on ice clouds, corresponding to the enhanced convection as indicated by reduced OLR. The increased precipitation appears to be associated with enhanced ice water

  7. Europe's eye on Mars: first spectacular results from Mars Express

    Science.gov (United States)

    2004-01-01

    Although the seven scientific instruments on board Mars Express are still undergoing a thorough calibration phase, they have already started collecting amazing results. The first high-resolution images and spectra of Mars have already been acquired. This first spectacular stereoscopic colour picture was taken on 14 January 2004 by ESA’s Mars Express satellite from 275 km above the surface of Mars by the High Resolution Stereo Camera (HRSC). This image is available on the ESA portal at: http://mars.esa.int The picture shows a portion of a 1700 km long and 65 km wide swath which was taken in south-north direction across the Grand Canyon of Mars (Valles Marineris). It is the first image of this size that shows the surface of Mars in high resolution (12 metres per pixel), in colour, and in 3D. The total area of the image on the Martian surface (top left corner) corresponds to 120 000 km². The lower part of the picture shows the same region in perspective view as if seen from a low-flying aircraft. This perspective view was generated on a computer from the original image data. One looks at a landscape which has been predominantly shaped by the erosional action of water. Millions of cubic kilometres of rock have been removed, and the surface features seen now such as mountain ranges, valleys, and mesas, have been formed. The HRSC is just one of the instruments to have collected exciting data. To learn more about the very promising beginning to ESA's scientific exploration of Mars, media representatives are invited to attend a press conference on Friday, 23 January 2004, at 11:00 CET at ESA’s Space Operations Centre in Darmstadt, Germany, and in video-conference with the other ESA centres. There, under the auspices of ESA Council Chair at Ministerial level, Germany's Minister for Education and Research, Mrs Edelgard Bulmahn, ESA's Director of the Scientific Programme, Prof. David Southwood and the Principal Investigators of all instruments on board Mars Express will

  8. Water on early Mars

    Science.gov (United States)

    Carr, M.H.

    1996-01-01

    Large flood channels, valley networks and a variety of features attributed to the action of ground ice indicate that Mars emerged from heavy bombardment 3.8 Ga ago, with an inventory of water at the surface equivalent to at least a few hundred metres spread over the whole planet, as compared with 3 km for the Earth. The mantle of Mars is much drier than that of the Earth, possibly as a result of global melting at the end of accretion and the lack of plate tectonics to subsequently reintroduce water into the interior. The surface water resided primarily in a porous, kilometres-thick megaregolith created by the high impact rates. Under today's climatic conditions groundwater is trapped below a thick permafrost zone. At the end of heavy bombardment any permafrost zone would have been much thinner because of the high heat flows, but climatic conditions may have been very different then, as suggested by erosion rates 1000 times higher than subsequent rates. Water trapped below the permafrost periodically erupted onto the surface to form large flood channels and lakes. Given abundant water at the surface and sustained volcanism, hydrothermal activity must have frequently occurred but we have yet to make the appropriate observations to detect the results of such activity.

  9. Water on early Mars.

    Science.gov (United States)

    Carr, M H

    1996-01-01

    Large flood channels, valley networks and a variety of features attributed to the action of ground ice indicate that Mars emerged from heavy bombardment 3.8 Ga ago, with an inventory of water at the surface equivalent to at least a few hundred metres spread over the whole planet, as compared with 3 km for the Earth. The mantle of Mars is much drier than that of the Earth, possibly as a result of global melting at the end of accretion and the lack of plate tectonics to subsequently reintroduce water into the interior. The surface water resided primarily in a porous, kilometres-thick megaregolith created by the high impact rates. Under today's climatic conditions groundwater is trapped below a thick permafrost zone. At the end of heavy bombardment any permafrost zone would have been much thinner because of the high heat flows, but climatic conditions may have been very different then, as suggested by erosion rates 1000 times higher than subsequent rates. Water trapped below the permafrost periodically erupted onto the surface to form large flood channels and lakes. Given abundant water at the surface and sustained volcanism, hydrothermal activity must have frequently occurred but we have yet to make the appropriate observations to detect the results of such activity.

  10. A Web Service Tool (SOAR) for the Dynamic Generation of L1 Grids of Coincident AIRS, AMSU and MODIS Satellite Sounding Radiance Data for Climate Studies

    Science.gov (United States)

    Halem, M.; Yesha, Y.; Tilmes, C.; Chapman, D.; Goldberg, M.; Zhou, L.

    2007-05-01

    Three decades of Earth remote sensing from NASA, NOAA and DOD operational and research satellites carrying successive generations of improved atmospheric sounder instruments have resulted in petabytes of radiance data with varying spatial and spectral resolutions being stored at different data archives in various data formats by the respective agencies. This evolution of sounders and the diversities of these archived data sets have led to data processing obstacles limiting the science community from readily accessing and analyzing such long-term climate data records. We address this problem by the development of a web based Service Oriented Atmospheric Radiance (SOAR) system built on the SOA paradigm that makes it practical for the science community to dynamically access, manipulate and generate long term records of L1 pre-gridded sounding radiances of coincident multi-sensor data for regions specified according to user chosen criteria. SOAR employs a modification of the standard Client Server interactions that allows users to represent themselves directly to the Process Server through their own web browsers. The browser uses AJAX to request Javascript libraries and DHTML interfaces that define the possible client interactions and communicates the SOAP messages to the Process server allowing for dynamic web dialogs with the user to take place on the fly. The Process Server is also connected to an underlying high performance compute cluster and storage system which provides much of the data processing capabilities required to service the client requests. The compute cluster employs optical communications to NOAA and NASA for accessing the data and under the governance of the Process Server invokes algorithms for on-demand spatial, temporal, and spectral gridding. Scientists can choose from a variety of statistical averaging techniques for compositing satellite observed sounder radiances from the AIRS, AMSU or MODIS instruments to form spatial-temporal grids for

  11. The Ocean Colour Climate Change Initiative: II. Spatial and Temporal Homogeneity of Satellite Data Retrieval Due to Systematic Effects in Atmospheric Correction Processors

    Science.gov (United States)

    Muller, Dagmar; Krasemann, Hajo; Brewin, Robert J. W.; Brockmann, Carsten; Deschamps, Pierre-Yves; Fomferra, Norman; Franz, Bryan A.; Grant, Mike G.; Groom, Steve B.; Melin, Frederic; Platt, Trevor; Regner, Peter; Sathyendranath, Shubha; Steinmetz, Francois; Swinton, John

    2015-01-01

    The established procedure to access the quality of atmospheric correction processors and their underlying algorithms is the comparison of satellite data products with related in-situ measurements. Although this approach addresses the accuracy of derived geophysical properties in a straight forward fashion, it is also limited in its ability to catch systematic sensor and processor dependent behaviour of satellite products along the scan-line, which might impair the usefulness of the data in spatial analyses. The Ocean Colour Climate Change Initiative (OC-CCI) aims to create an ocean colour dataset on a global scale to meet the demands of the ecosystem modelling community. The need for products with increasing spatial and temporal resolution that also show as little systematic and random errors as possible, increases. Due to cloud cover, even temporal means can be influenced by along-scanline artefacts if the observations are not balanced and effects cannot be cancelled out mutually. These effects can arise from a multitude of results which are not easily separated, if at all. Among the sources of artefacts, there are some sensor-specific calibration issues which should lead to similar responses in all processors, as well as processor-specific features which correspond with the individual choices in the algorithms. A set of methods is proposed and applied to MERIS data over two regions of interest in the North Atlantic and the South Pacific Gyre. The normalised water leaving reflectance products of four atmospheric correction processors, which have also been evaluated in match-up analysis, is analysed in order to find and interpret systematic effects across track. These results are summed up with a semi-objective ranking and are used as a complement to the match-up analysis in the decision for the best Atmospheric Correction (AC) processor. Although the need for discussion remains concerning the absolutes by which to judge an AC processor, this example demonstrates

  12. Satellite Communication.

    Science.gov (United States)

    Technology Teacher, 1985

    1985-01-01

    Presents a discussion of communication satellites: explains the principles of satellite communication, describes examples of how governments and industries are currently applying communication satellites, analyzes issues confronting satellite communication, links mathematics and science to the study of satellite communication, and applies…

  13. Satellite Upper Air Network (SUAN)

    Science.gov (United States)

    Reale, Tony L.; Thorne, Peter

    2004-10-01

    During the past 20 years of NOAA operational polar satellites, it has become evident that a growing problem concerning their utilization in Climate and also Numerical Weather Prediction (NWP) applications are the systematic errors and uncertainties inherent in the satellite measurements. Similar arguments can be made for global radiosonde observations. These uncertainties are often larger than the sensitive signals and processes, that satellite and radiosonde measurements are designed to reveal, particularly in the realm of climate. Possible strategies to quantify and compensate for these problems include the analysis of satellite overlap data and/or available collocations of satellite and ground truth (radiosonde) observations. However, overlap observations are typically not available except in extreme polar regions and current sampling strategies for compiling collocated radiosonde and satellite observations are insufficient, further compounding the inherent uncertainties in the ground-truth radiosonde data. A Satellite Upper Air Network is proposed to provide reference radiosonde launches coincident with operational polar satellite(s) overpass. The SUAN consist of 36 global radiosonde stations sub-sampled from the Global Upper Air Network (GUAN), and is designed to provide a robust, global sample of collocated radiosonde and satellite observations conducive to the monitoring and validation of satellite and radiosonde observations. The routine operation of such a network in conjunction with operational polar satellites would provide a long-term of performance for critical observations of particular importance for climate. The following report presents a candidate network of 36 upper-air sites that could comprise a SUAN. Their selection along with the mutual benefit across the satellite, radiosonde, climate, numerical weather prediction (NWP) and radiative transfer (RT) model areas are discussed.

  14. Assessing the Sensitivity of Satellite-Derived Estimates of Ice Sheet Mass Balance to Regional Climate Model Simulations of Snow Accumulation and Firn Compaction

    Science.gov (United States)

    Briggs, K.; Shepherd, A.; Horwath, M.; Horvath, A.; Nagler, T.; Wuite, J.; Muir, A.; Gilbert, L.; Mouginot, J.

    2015-12-01

    Surface mass balance (SMB) estimates from Regional Climate Models (RCMs) are fundamental for assessing and understanding ice sheet mass trends. Mass budget and altimetry assessments rely on RCMs both directly for estimates of the SMB contribution to the total mass trend, and indirectly for ancillary data in the form of firn compaction corrections. As such, mass balance assessments can be highly sensitive to RCM outputs and therefore their accuracy. Here we assess the extent to which geodetic measurements of mass balance are sensitive to RCM model outputs at different resolutions. We achieve this by comparing SMB dependent estimates of mass balance from the mass budget method and altimetry, with those from satellite gravimetry that are independent of SMB estimates. Using the outputs of the RACMO/ANT 2.3 model at 5.5 km and 27 km horizontal spatial resolution, we generate estimates of mass balance using the mass budget method and altimetry for the Western Palmer Land region of the Antarctic Peninsula between 2003 and 2014. We find a 19% increase in the long-term (1980 to 2014) mean annual SMB for the region when enhancing the model resolution to 5.5 km. This translates into an approximate 50% reduction in the total mass loss from 2003 to 2014 calculated with the mass budget method and a 15% increase in the altimetry estimate. The use of the enhanced resolution product leads to consistency between the estimates of mass loss from the altimetry and the mass budget method that is not observed with the coarser resolution product, in which estimates of cumulative mass fall beyond the relative errors. Critically, when using the 5.5 km product, we find excellent agreement, both in pattern and magnitude, with the independent estimate derived from gravimetry. Our results point toward the crucial need for high resolution SMB products from RCMs for mass balance assessments, particularly in regions of high mass turnover and complex terrain as found over the Antarctic Peninsula.

  15. Using precipitation, vertical root distribution, and satellite-retrieved vegetation information to parameterize water stress in a Penman-Monteith approach to evapotranspiration modeling under Mediterranean climate

    Science.gov (United States)

    Bai, Yun; Zhang, Jiahua; Zhang, Sha; Koju, Upama Ashish; Yao, Fengmei; Igbawua, Tertsea

    2017-03-01

    Recent studies have shown that global Penman-Monteith equation based (PM-based) models poorly simulate water stress when estimating evapotranspiration (ET) in areas having a Mediterranean climate (AMC). In this study, we propose a novel approach using precipitation, vertical root distribution (VRD), and satellite-retrieved vegetation information to simulate water stress in a PM-based model (RS-WBPM) to address this issue. A multilayer water balance module is employed to simulate the soil water stress factor (SWSF) of multiple soil layers at different depths. The water stress factor (WSF) for surface evapotranspiration is determined by VRD information and SWSF in each layer. Additionally, four older PM-based models (PMOV) are evaluated at 27 flux sites in AMC. Results show that PMOV fails to estimate the magnitude or capture the variation of ET in summer at most sites, whereas RS-WBPM is successful. The daily ET resulting from RS-WBPM incorporating recommended VI (NDVI for shrub and EVI for other biomes) agrees well with observations, with R2=0.60 (RMSE = 18.72 W m-2) for all 27 sites and R2=0.62 (RMSE = 18.21 W m-2) for 25 nonagricultural sites. However, combined results from the optimum older PM-based models at specific sites show R2 values of only 0.50 (RMSE = 20.74 W m-2) for all 27 sites. RS-WBPM is also found to outperform other ET models that also incorporate a soil water balance module. As all inputs of RS-WBPM are globally available, the results from RS-WBPM are encouraging and imply the potential of its implementation on a regional and global scale.

  16. Satellite Monitoring the Spatial-Temporal Dynamics of Desertification in Response to Climate Change and Human Activities across the Ordos Plateau, China

    Directory of Open Access Journals (Sweden)

    Qiang Guo

    2017-05-01

    Full Text Available The Ordos Plateau, a typical semi-arid area in northern China, has experienced severe wind erosion events that have stripped the agriculturally important finer fraction of the topsoil and caused dust events that often impact the air quality in northern China and the surrounding regions. Both climate change and human activities have been considered key factors in the desertification process. This study used multi-spectral Landsat Thematic Mapper (TM, Enhanced Thematic Mapper Plus (ETM+ and Operational Land Imager (OLI remote sensing data collected in 2000, 2006, 2010 and 2015 to generate a temporal series of the modified soil-adjusted vegetation index (MSAVI, bare soil index (BSI and albedo products in the Ordos Plateau. Based on these satellite products and the decision tree method, we quantitatively assessed the desertification status over the past 15 years since 2000. Furthermore, a quantitative method was used to assess the roles of driving forces in desertification dynamics using net primary productivity (NPP as a commensurable indicator. The results showed that the area of non-desertification land increased from 6647 km2 in 2000 to 15,961 km2 in 2015, while the area of severe desertification land decreased from 16,161 km2 in 2000 to 8,331 km2 in 2015. During the period 2006–2015, the effect of human activities, especially the ecological recovery projects implemented in northern China, was the main cause of desertification reversion in this region. Therefore, ecological recovery projects are still required to promote harmonious development between nature and human society in ecologically fragile regions like the Ordos Plateau.

  17. Changes in satellite-derived spring vegetation green-up date and its linkage to climate in China from 1982 to 2010: a multimethod analysis.

    Science.gov (United States)

    Cong, Nan; Wang, Tao; Nan, Huijuan; Ma, Yuecun; Wang, Xuhui; Myneni, Ranga B; Piao, Shilong

    2013-03-01

    The change in spring phenology is recognized to exert a major influence on carbon balance dynamics in temperate ecosystems. Over the past several decades, several studies focused on shifts in spring phenology; however, large uncertainties still exist, and one understudied source could be the method implemented in retrieving satellite-derived spring phenology. To account for this potential uncertainty, we conducted a multimethod investigation to quantify changes in vegetation green-up date from 1982 to 2010 over temperate China, and to characterize climatic controls on spring phenology. Over temperate China, the five methods estimated that the vegetation green-up onset date advanced, on average, at a rate of 1.3 ± 0.6 days per decade (ranging from 0.4 to 1.9 days per decade) over the last 29 years. Moreover, the sign of the trends in vegetation green-up date derived from the five methods were broadly consistent spatially and for different vegetation types, but with large differences in the magnitude of the trend. The large intermethod variance was notably observed in arid and semiarid vegetation types. Our results also showed that change in vegetation green-up date is more closely correlated with temperature than with precipitation. However, the temperature sensitivity of spring vegetation green-up date became higher as precipitation increased, implying that precipitation is an important regulator of the response of vegetation spring phenology to change in temperature. This intricate linkage between spring phenology and precipitation must be taken into account in current phenological models which are mostly driven by temperature. © 2012 Blackwell Publishing Ltd.

  18. Evaluation of three different data fusion approaches that uses satellite soil moisture from different passive microwave sensors to construct one consistent climate record

    Science.gov (United States)

    van der Schalie, Robin; de Jeu, Richard; Kerr, Yann; Wigneron, Jean-Pierre; Rodríguez-Fernández, Nemesio; Al-Yaari, Amen; Drusch, Matthias; Mecklenburg, Susanne; Dolman, Han

    2016-04-01

    Datasets that are derived from satellite observations are becoming increasingly important for measuring key parameters of the Earth's climate and are therefore crucial in research on climate change, giving the opportunity to researchers to detect anomalies and long-term trends globally. One of these key parameters is soil moisture (SM), which has a large impact on water, energy and biogeochemical cycles worldwide. A long-term SM data record from active and passive microwave satellite observations was developed as part of ESA's Climate Change Initiative (ESA-CCI-SM, http://www.esa-soilmoisture-cci.org/). Currently the dataset covers a period from 1978 to 2014 and is updated regularly, observations from a several microwave satellites including: ERS-1, ERS-2, METOP-A, Nimbus 7 SMMR, DMSP SSM/I, TRMM TMI, Aqua AMSRE, Coriolis WindSat, and GCOM-W1 AMSR2. In 2009, ESA launched the Soil Moisture and Ocean Salinity (SMOS, Kerr et al., 2010) mission, carrying onboard a unique L-band radiometer, but its SM retrievals are not yet part of this dataset. Due to the different radiometric characteristics of SMOS, integrating SMOS into the ESA-CCI-SM dataset is not straight forward. Therefore several approaches have been tested to fuse soil moisture retrievals from SMOS and AMSRE, which currently forms the basis of the passive microwave part within ESA-CCI-SM project. These approaches are: 1. A Neural Network Fusion approach (Rodríguez-Fernández et al., 2015), 2. A regression approach (Wigneron et al., 2004; Al-Yaari et al., 2015) and 3. A radiative transfer based approach, using the Land Parameter Retrieval Model (Van der Schalie et al., 2016). This study evaluates the three different approaches and tests their skills against multiple datasets, including MERRA-Land, ERA-Interim/Land, the current ESA-CCI-SM v2.2 and in situ measurements from the International Soil Moisture Network and present a recommendation for the potential integration of SMOS soil moisture into the ESA

  19. Mars @ ASDC

    Science.gov (United States)

    Carraro, Francesco

    "Mars @ ASDC" is a project born with the goal of using the new web technologies to assist researches involved in the study of Mars. This project employs Mars map and javascript APIs provided by Google to visualize data acquired by space missions on the planet. So far, visualization of tracks acquired by MARSIS and regions observed by VIRTIS-Rosetta has been implemented. The main reason for the creation of this kind of tool is the difficulty in handling hundreds or thousands of acquisitions, like the ones from MARSIS, and the consequent difficulty in finding observations related to a particular region. This led to the development of a tool which allows to search for acquisitions either by defining the region of interest through a set of geometrical parameters or by manually selecting the region on the map through a few mouse clicks The system allows the visualization of tracks (acquired by MARSIS) or regions (acquired by VIRTIS-Rosetta) which intersect the user defined region. MARSIS tracks can be visualized both in Mercator and polar projections while the regions observed by VIRTIS can presently be visualized only in Mercator projection. The Mercator projection is the standard map provided by Google. The polar projections are provided by NASA and have been developed to be used in combination with APIs provided by Google The whole project has been developed following the "open source" philosophy: the client-side code which handles the functioning of the web page is written in javascript; the server-side code which executes the searches for tracks or regions is written in PHP and the DB which undergoes the system is MySQL.

  20. Dry Mars: Parched Rocks and Fallen Dust

    Science.gov (United States)

    Treiman, Allan H.

    2001-01-01

    While "following the water" to find life on Mars, it is easy to overlook evidence that Mars is harshly dry, and to neglect ideas that do not invoke water. Direct evidence for a dry Mars comes from the ALH 84001 meteorite, which has seen little or no liquid water during its last 3.9 billion years on Mars. Its aridity is difficult to reconcile with a Mars of abundant near-surface surface water or with episodes of warm wet climate. Alternative scenarios are also possible, even likely, for the martian gullies and debris flows that have been cited as evidence of liquid water. It is reasonable that the gullies flows are the remnants of massive dust avalanches, comparable to large climax snow avalanches seen on Earth. Mars' surface is now desiccated, and at least part of it has been equally desiccated for the past 3.9 billion years. With this background, and the wealth of atmospheric, imaging, and chemical data available from Mars, one must be very cautious in evaluating claims for liquid water recently at or near Mars' surface. Additional information is contained in the original extended abstract.

  1. MNSM - A Future Mars Network Science Mission

    Science.gov (United States)

    Chicarro, A. F.

    2012-04-01

    partners have expressed an interest to participate (e.g., Japan, Russia, China). Also, NASA' s 2016 GEMS one-station mission could be a very valuable precursor for MNSM, if selected as NASA' s next Discovery mission. The proposed Mars Network Science Mission would focus on the early Mars, providing essential constraints on geophysical, geochemical, and geological models of Mars' evolution and a better understanding of SNC meteorites and future returned Martian samples. Measurements on the seismology, geodesy, magnetic field and surface heat flow would reveal the internal structure, activity and composition of Mars, its thermal structure and its magnetic evolution. Meteorological surface measurements would allow monitoring the atmospheric dynamics at the boundary layer (coupled with orbital measurements) to infer the climate patterns. Such mission can also provide important insights into the astrobiological conditions of Mars, in particular its magnetic field, heat flow and climate evolution. The Mars Network Science Mission represents a unique tool to perform new investigations of Mars, which could not be addressed by any other means. It would fill a longstanding gap in the scientific exploration of the Solar System by performing in-situ investigations of the interior of an Earth-like planet other than our own and provide unique and critical information about the fundamental processes of terrestrial planetary formation and evolution. The long-term goal of Mars robotic exploration in Europe remains the return of rock and soil samples from the Martian surface before eventually Humans explore Mars, but the Mars Network would provide the context in which returned samples should be interpreted.

  2. Long-term variability of UV irradiance over Northern Eurasia according to satellite measurements, ERA-INTERIM dataset and INM-RSHU chemical climate model

    Science.gov (United States)

    Chubarova, Nataly; Pastukhova, Anna; Zhdanova, Ekaterina; Khlestova, Julia; Poliukhov, Alexei; Smyshlyaev, Sergei; Galin, Vener

    2017-04-01

    We present the results of long-term erythemal UV irradiance (ERY) changes over the territory of Northern Eurasia according to the ERA-INTERIM reanalysis dataset, INM-RSHU chemical climate model (CCM), and TOMS and OMI satellite data with the correction on absorbing aerosol based on the new Macv2 climatology updated from Kinne et al. (2013) over the 1979-2015 period. We show the existence of the pronounced positive ERY trend due to ozone in spring and summer over Europe and over the central areas of Siberia (up 3% over the decade). The changes in cloud cover provide even more significant ERY increase (up to 6-8% per decade). However, over Arctic region there is a pronounced negative ERY trend probably due to the effects of melting ice on global circulation processes. The combination of ozone and cloud effects provides the enhanced increase of the overall ERY trend: up to 6-9% in spring and summer over Eastern Europe, some regions of Siberia and the Far East. In addition, based on the method described in (Chubarova, Zhdanova, 2013) we estimated changes in UV resources over Northern Eurasia since 1979. We show that for the first skin type there is a significant geographical shift of UV categories: the increase in the UV optimum area in winter, where the vitamin D generation is possible without risk of getting sunburn, and its reducing in other months due to decrease in ozone and clouds. We also analyze the long-term UV changes simulated according to different scenarios using the INM-RSHU CCM. There is a general agreement between CCM and observational datasets, however, ERY trends due to cloudiness do not correspond sometimes in space and are smaller. We show that the positive ERY trend due to ozone is determined by the anthropogenic emissions of halogens. The variations in natural factors (solar activity and ocean surface temperature, stratospheric aerosol) only provide the increase in ERY dispersion. References: Kinne, S., O'Donnel D., Stier P., et al., J. Adv. Model

  3. Resonances and Tides in Natural Satellites Systems. (Breton Title: Ressonâncias e Marés em Sistemas de Satélites Naturais.) Resonancias y Mareas en Sistemas de Satélites Naturales

    Science.gov (United States)

    Callegari, Nelson, Jr.

    2006-12-01

    In this work we describe some aspects of the dynamics of the mean-motion resonances. Emphasis to the case of resonances between regular satellites of the giant planets will be given, even so some aspects of the physics of the resonances in extra-solar planetary systems are also briefly treated. The role of the resonances in satellites systems is discussed through examples, showing how certain resonances, and its relations with the tidal dissipation effects, can be the key of the explanation of some phenomena still not explained in the Solar System. Amongst some examples we highlight the problem of the resurfacing of Enceladus, the existence of active volcanoes in Io, and the possible existence of the subsurface ocean in Europe. This work has as objective the divulgation of some topics in Celestial Mechanics and Planetary Sciences for an undergraduate public in exact sciences, as Astronomy and Physics, and not their detailed description. Neste trabalho descrevemos alguns aspectos da dinâmica de ressonâncias de movimentos médios. Será dada ênfase maior ao caso de ressonâncias entre satélites regulares dos planetas gigantes, embora alguns aspectos da física das ressonâncias em sistemas planetários extra-solares também sejam discutidos brevemente. A importância do estudo de ressonâncias em sistemas de satélites é discutida mais detalhadamente através de exemplos, mostrando como certas ressonâncias e suas relações com efeitos de dissipação de maré podem ser a chave de parte da explicação de alguns fenômenos ainda não explicados no Sistema Solar. Dentre vários exemplos destacamos o problema da remodelagem da superfície do satélite Enceladus, a existência de vulcões ativos em Io, e a possível existência do oceano subterrâneo em Europa. Este trabalho tem como objetivo a divulgação de alguns tópicos de Mecânica Celeste e Planetologia para um público de nível de graduação em disciplinas na área de exatas, em especial Astronomia e F

  4. Mars Public Engagement Overview

    Science.gov (United States)

    Johnson, Christine

    2009-01-01

    This viewgraph presentation reviews the Mars public engagement goal to understand and protect our home planet, explore the Universe and search for life, and to inspire the next generation of explorers. Teacher workshops, robotics education, Mars student imaging and analysis programs, MARS Student Imaging Project (MSIP), Russian student participation, MARS museum visualization alliance, and commercialization concepts are all addressed in this project.

  5. Mars Surveyor '98 MVACS Robotic Arm Control System Design Concepts

    Science.gov (United States)

    Bonitz, Robert G.

    1997-01-01

    This paper describes the control system design concepts for the Mars Volatiles and Climate Surveyor (MVACS) Robotic Arm which supports the scientific investigations to be conducted as part of the Mars Surveyor '98 Lander project. Novel solutions are presented to some of the unique problems encountered in this demanding space application with its tight constraints on mass, power, volume, and computing power.

  6. The H Corona of Mars

    Science.gov (United States)

    Chaffin, Michael Scott

    The atmosphere of every planet is surrounded by a tenuous cloud of hydrogen gas, referred to as a hydrogen corona. At Mars, a substantial fraction of the H present in the corona is moving fast enough to escape the planet's gravity, permanently removing H from the Martian atmosphere. Because this H is ultimately derived from lower atmospheric water, loss of H from Mars is capable of drying and oxidizing the planet over geologic time. Understanding the processes that supply the H corona and control its escape is therefore essential for a complete understanding of the climate history of Mars and for assessing its habitability. In this thesis, I present the most complete analysis of the H corona ever attempted, surveying eight years of data gathered by the ultraviolet spectrograph SPICAM on Mars Express. Using a coupled radiative transfer and physical density model, I interpret brightness measurements of the corona in terms of escape rates of H from the planet, uncovering an order-of-magnitude variability in the H escape rate never before detected. These variations are interpreted using a completely new photochemical model of the atmosphere, demonstrating that newly discovered high altitude water vapor layers are sufficient to produce the observed variation. Finally, I present first results of the SPICAM successor instrument IUVS, an imaging ultraviolet spectrograph carried by NASA's MAVEN spacecraft. IUVS measurements are producing the most complete dataset ever gathered for the Martian H corona, enabling supply and loss processes to be assessed in more complete detail than ever before. This dataset will allow present-day loss rates to be extrapolated into the past, determining the absolute amount of water Mars has lost to space over the course of its history. Planets the size of Mars may be common throughout the universe; the work of this thesis is one step toward assessing the habitability of such planets in general.

  7. Glacial and Periglacial Chemical Weathering on Mars: New Results and New Questions from Field Analog Studies and Mars Remote Sensing

    Science.gov (United States)

    Horgan, B.; Scudder, N.; Rutledge, A.; Ackiss, S.

    2016-09-01

    Ice has been a powerful physical weather agent on Mars through geologic time, however, it is less well understood how much chemical weathering ice has caused on Mars, and how the mode of alteration has changed with the climate over time.

  8. Amazonian Mid-Latitude Regional Glaciation on Mars: Lineated Valley Fill, Lobate Debris Aprons and Plateau Deposits at the Dichotomy Boundary and Implications for Climate Change

    Science.gov (United States)

    Head, J. W.; Marchant, D. R.

    2005-12-01

    The dichotomy boundary on Mars represents a distinct geologic, topographic, morphologic and crustal thickness boundary that is characterized by a wide range of modificational processes. The Deuteronilus-Protonilus region represents the area where the boundary reaches its highest latitude. The fretted terrain, located in the vicinity of the dichotomy boundary at these mid-northern latitudes on Mars, displays two enigmatic terrain types: lobate debris aprons (LDA) and lineated valley fill (LVF). The prevailing hypotheses for their origin has been mass wasting from mesa margins and valley walls, with movement periodically assisted by groundwater seepage or atmospheric vapor diffusion into the debris aprons, causing ice-assisted creep. Creep from opposite valley walls and convergence in valley centers has been called on to explain the parallel, along-valley lineations, and little evidence has been found for down-valley movement. New higher-resolution THEMIS and MOC data, however, show compelling evidence for a more integrated picture of LVF formation, suggesting a significant role for regional glaciation. We find evidence for: 1) localized alcoves, sources of hundreds of narrow, lobate concentric-ridged debris flows; 2) bulbous-headed tributary valley systems, which contain converging LVF that feeds into larger valley systems; 3) rounded-sharp-paired intersections of the corners of tributary entrances into main valleys, with sharp corners pointing down-flow; 4) narrow arete-like linear plateau ridge remnants, commonly parallel to LVF; 5) horseshoe-shaped ridges up-valley of topographic obstacles, with deformed and folded upslope LVF; 6) convergence and merging of LVF in the down-valley directions; 7) deformation, distortion and folding of LVF in the vicinity of convergence; 8) distinctive lobe-shaped termini where LVF emerges into the northern lowlands. We interpret these LVF features to have formed as parts of integrated valley glacial systems extending hundreds of km

  9. Dynamical Modeling of Mars' Paleoclimate

    Science.gov (United States)

    Richardson, Mark I.

    2004-01-01

    This report summarizes work undertaken under a one-year grant from the NASA Mars Fundamental Research Program. The goal of the project was to initiate studies of the response of the Martian climate to changes in planetary obliquity and orbital elements. This work was undertaken with a three-dimensional numerical climate model based on the Geophysical Fluid Dynamics Laboratory (GFDL) Skyhi General Circulation Model (GCM). The Mars GCM code was adapted to simulate various obliquity and orbital parameter states. Using a version of the model with a basic water cycle (ice caps, vapor, and clouds), we examined changes in atmospheric water abundances and in the distribution of water ice sheets on the surface. This work resulted in a paper published in the Journal of Geophysical Research - Planets. In addition, the project saw the initial incorporation of a regolith water transport and storage scheme into the model. This scheme allows for interaction between water in the pores of the near subsurface (<3m) and the atmosphere. This work was not complete by the end of the one-year grant, but is now continuing within the auspices of a three-year grant of the same title awarded by the Mars Fundamental Research Program in late 2003.

  10. Recent Aeolian Dune Change on Mars

    Science.gov (United States)

    Bourke, M. C.; Edgett, K. S.; Cantor, B. A.

    2007-01-01

    Previous comparisons of Martian aeolian dunes in satellite images have not detected any change in dune form or position. Here, we show dome dunes in the north polar region that shrank and then disappeared over a period of 3.04 Mars years (5.7 Earth years), while larger, neighboring dunes showed no erosion or movement. The removal of sand from these dunes indicates that not only is the threshold wind speed for saltation exceeded under present conditions on Mars, but that any sand that is available for transport is likely to be moved. Dunes that show no evidence of change could be crusted, indurated. or subject to infrequent episodes of movement.

  11. Connecting Robots and Humans in Mars Exploration

    Science.gov (United States)

    Friedman, Louis

    2000-07-01

    Mars exploration is a very special public interest. It's preeminence in the national space policy calling for "sustained robotic presence on the surface," international space policy (witness the now aborted international plan for sample return, and also aborted Russian "national Mars program") and the media attention to Mars exploration are two manifestations of that interest. Among a large segment of the public there is an implicit (mis)understanding that we are sending humans to Mars. Even among those who know that isn't already a national or international policy, many think it is the next human exploration goal. At the same time the resources for Mars exploration in the U.S. and other country's space programs are a very small part of space budgets. Very little is being applied to direct preparations for human flight. This was true before the 1999 mission losses in the United States, and it is more true today. The author's thesis is that the public interest and the space program response to Mars exploration are inconsistent. This inconsistency probably results from an explicit space policy contradiction: Mars exploration is popular because of the implicit pull of Mars as the target for human exploration, but no synergy is permitted between the human and robotic programs to carry out the program. It is not permitted because of narrow, political thinking. In this paper we try to lay out the case for overcoming that thinking, even while not committing to any premature political initiative. This paper sets out a rationale for Mars exploration and uses it to then define recommended elements of the programs: missions, science objectives, technology. That consideration is broader than the immediate issue of recovering from the failures of Mars Climate OrbIter, Mars Polar Lander and the Deep Space 2 microprobes in late 1999. But we cannot ignore those failures. They are causing a slow down Mars exploration. Not only were the three missions lost, with their planned

  12. Planet-wide sand motion on mars

    Science.gov (United States)

    Bridges, N.T.; Bourke, M.C.; Geissler, P.E.; Banks, M.E.; Colon, C.; Diniega, S.; Golombek, M.P.; Hansen, C.J.; Mattson, S.; McEwen, A.S.; Mellon, M.T.; Stantzos, N.; Thomson, B.J.

    2012-01-01

    Prior to Mars Reconnaissance Orbiter data, images of Mars showed no direct evidence for dune and ripple motion. This was consistent with climate models and lander measurements indicating that winds of sufficient intensity to mobilize sand were rare in the low-density atmosphere. We show that many sand ripples and dunes across Mars exhibit movement of as much as a few meters per year, demonstrating that Martian sand migrates under current conditions in diverse areas of the planet. Most motion is probably driven by wind gusts that are not resolved in global circulation models. A past climate with a thicker atmosphere is only required to move large ripples that contain coarse grains. ?? 2012 Geological Society of America.

  13. Geologic Evolution of Mars' North Polar Layered Deposits and Related Materials from Mars Odyssey THEMIS

    Science.gov (United States)

    Vasavada, A. R.; Richardson, M. I.; Byrne, S.; Ivanov, A. B.; Christensen, P. R.

    2003-01-01

    The presence of a thick sequence of horizontal layers of ice-rich material at Mars north pole, dissected by troughs and eroding at its margins, is undoubtedly telling us something about the evolution of Mars climate we just don't know what yet. The North Polar Layered Deposits (NPLD) most likely formed as astronomically driven climate variations led to the deposition of conformable, areally extensive layers of ice and dust over the polar region. More recently, the balance seems to have fundamentally shifted to net erosion, as evidenced by the many troughs within the NPLD and the steep, arcuate scarps present near its margins, both of which expose layering.

  14. Defining the Mars Ascent Problem for Sample Return

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J

    2008-07-31

    Lifting geology samples off of Mars is both a daunting technical problem for propulsion experts and a cultural challenge for the entire community that plans and implements planetary science missions. The vast majority of science spacecraft require propulsive maneuvers that are similar to what is done routinely with communication satellites, so most needs have been met by adapting hardware and methods from the satellite industry. While it is even possible to reach Earth from the surface of the moon using such traditional technology, ascending from the surface of Mars is beyond proven capability for either solid or liquid propellant rocket technology. Miniature rocket stages for a Mars ascent vehicle would need to be over 80 percent propellant by mass. It is argued that the planetary community faces a steep learning curve toward nontraditional propulsion expertise, in order to successfully accomplish a Mars sample return mission. A cultural shift may be needed to accommodate more technical risk acceptance during the technology development phase.

  15. MarsTwin: an M-mission to Mars with two geophysical laboratories

    Science.gov (United States)

    Dehant, V. M.; Breuer, D.; Grott, M.; Spohn, T.; Lognonne, P.; Read, P. L.; Vennerstroem, S.; Banerdt, B.

    2010-12-01

    Mars-Twin - a mission proposed for the running ESA cosmic vision M call - if selected it will be the first European mission to focus on interior processes and the early evolution of Mars, providing essential constraints for models of the thermal, geochemical, and geologic evolution of Mars and for a better understanding of SNC meteorites and future samples from Mars. Our fundamental understanding of the interior of the Earth comes from geophysics, geodesy, geochemistry, geomagnetism, and petrology. For geophysics, seismology, geodesy, magnetic field measurements, and surface heat flow have revealed the basic internal layering of the Earth, its thermal structure, its gross compositional stratification, as well as significant lateral variations in these quantities. The landers will also provide meteorological stations to monitor the Martian meteorology and climate and to obtain new measurements in the Martian boundary layer. The Mars-Twin mission will fill a longstanding gap in the scientific exploration of the solar system by performing an in-situ investigation of the interior of an Earth-like planet other than our own. Mars-Twin will provide unique and critical information about the fundamental processes of terrestrial planet formation and evolution. This investigation has been ranked as a high priority in virtually every set of European, US and international high-level planetary science recommendations for the past 30 years, and the objectives for the Mars-Twin mission are derived directly from these recommendations. In addition to geophysics, the mission will provide important constraints for the Astrobiology of Mars by helping to understand why Mars fails to have a magnetic field, by helping to understand the evolution of the climate, and by providing a limit to the chemoautrophic biosphere through a measurement of the heat flow. The paper will also address the synergy between the lander instruments and the possible orbiter instruments.

  16. Planetary climates (princeton primers in climate)

    CERN Document Server

    Ingersoll, Andrew

    2013-01-01

    This concise, sophisticated introduction to planetary climates explains the global physical and chemical processes that determine climate on any planet or major planetary satellite--from Mercury to Neptune and even large moons such as Saturn's Titan. Although the climates of other worlds are extremely diverse, the chemical and physical processes that shape their dynamics are the same. As this book makes clear, the better we can understand how various planetary climates formed and evolved, the better we can understand Earth's climate history and future.

  17. Rotorcrafts for Mars Exploration

    Science.gov (United States)

    Balaram, J.; Tokumaru, P. T.

    2014-06-01

    Rotorcraft mobility provides a number of useful capabilities to potential Mars missions. We present some recent results relating to the design and test of Mars rotorcraft mobility elements, and aspects of rotorcraft system and mission design.

  18. Mars Gashopper Airplane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Gas Hopper Airplane, or "gashopper" is a novel concept for propulsion of a robust Mars flight and surface exploration vehicle that utilizes indigenous CO2...

  19. The Greenhouse Gas Climate Change Initiative (GHG-CCI): comparison and quality assessment of near-surface-sensitive satellite-derived CO2 and CH4 global data sets

    Science.gov (United States)

    Buchwitz, Michael

    2013-04-01

    The GHG-CCI project is one of several projects of the European Space Agency's (ESA) Climate Change Initiative (CCI). The goal of the CCI is to generate and deliver data sets of various satellite-derived Essential Climate Variables (ECVs) in line with GCOS (Global Climate Observing System) requirements. The "ECV Greenhouse Gases" (ECV GHG) is the global distribution of important climate relevant gases - atmospheric CO2 and CH4 - with a quality sufficient to obtain information on regional CO2 and CH4 sources and sinks. Two satellite instruments deliver the main input data for GHG-CCI: SCIAMACHY/ENVISAT and TANSO-FTS/GOSAT. The first order priority goal of GHG-CCI is the further development of retrieval algorithms for near-surface-sensitive column-averaged dry air mole fractions of CO2 and CH4, denoted XCO2 and XCH4, to meet the demanding user requirements. GHG-CCI focusses on four core data products: XCO2 from SCIAMACHY and TANSO and XCH4 from the same two sensors. For each of the four core data products at least two candidate retrieval algorithms have been independently further developed and the corresponding data products have been quality assessed and inter-compared. This activity is referred to as "Round Robin" (RR) activity within the CCI. The main goal of the RR was to identify for each of the four core products which algorithm to be used to generate the Climate Research Data Package (CRDP), which will essentially be the first version of the ECV GHG. This manuscript gives an overview about the GHG-CCI RR and related activities. This comprises the establishment of the user requirements, the improvement of the candidate retrieval algorithms and comparisons with ground-based observations and models. The manuscript summarizes the final RR algorithm selection decision and its justification. Comparison with ground-based Total Carbon Column Observing Network (TCCON) data indicates that the "breakthrough" single measurement precision requirement has been met for

  20. Satellites in Canadian broadcasting

    Science.gov (United States)

    Siocos, C. A.

    The involvement of Canadian broadcasting and related enterprises in satellite telecommunications is surveyed. This includes point-to-point transmissions and direct ones to the general public. The mode of such utilizations is indicated in both these cases. For the forthcoming DBS systems the many types of service offerings and utilization concepts under discussion elasewhere are presented as well as the business prospects and regulatory climate offering them.

  1. Operational generation of AVHRR-based cloud products for Europe and the Arctic at EUMETSAT's Satellite Application Facility on Climate Monitoring (CM-SAF

    Directory of Open Access Journals (Sweden)

    F. Kaspar

    2009-04-01

    Full Text Available The Satelite Application Facility on Climate Monitoring has implemented a new processing environment for AVHRR-based climate monitoring products. AVHRR measurements from NOAA-17, NOAA-18 and MetOp-A are utilized to generate daily and monthly means of several cloud parameters for Europe and the Inner Arctic: Cloud fraction, cloud types, cloud phase, cloud top height, cloud optical thickness and cloud liquid water path.

  2. Satellite RNAs and Satellite Viruses.

    Science.gov (United States)

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA.

  3. New perspectives on ancient Mars.

    Science.gov (United States)

    Solomon, Sean C; Aharonson, Oded; Aurnou, Jonathan M; Banerdt, W Bruce; Carr, Michael H; Dombard, Andrew J; Frey, Herbert V; Golombek, Matthew P; Hauck, Steven A; Head, James W; Jakosky, Bruce M; Johnson, Catherine L; McGovern, Patrick J; Neumann, Gregory A; Phillips, Roger J; Smith, David E; Zuber, Maria T

    2005-02-25

    Mars was most active during its first billion years. The core, mantle, and crust formed within approximately 50 million years of solar system formation. A magnetic dynamo in a convecting fluid core magnetized the crust, and the global field shielded a more massive early atmosphere against solar wind stripping. The Tharsis province became a focus for volcanism, deformation, and outgassing of water and carbon dioxide in quantities possibly sufficient to induce episodes of climate warming. Surficial and near-surface water contributed to regionally extensive erosion, sediment transport, and chemical alteration. Deep hydrothermal circulation accelerated crustal cooling, preserved variations in crustal thickness, and modified patterns of crustal magnetization.

  4. Centriolar satellites

    DEFF Research Database (Denmark)

    Tollenaere, Maxim A X; Mailand, Niels; Bekker-Jensen, Simon

    2015-01-01

    Centriolar satellites are small, microscopically visible granules that cluster around centrosomes. These structures, which contain numerous proteins directly involved in centrosome maintenance, ciliogenesis, and neurogenesis, have traditionally been viewed as vehicles for protein trafficking...... highlight newly discovered regulatory mechanisms targeting centriolar satellites and their functional status, and we discuss how defects in centriolar satellite components are intimately linked to a wide spectrum of human diseases....

  5. Analysis of Maritime Mobile Satellite Communication Systems

    Science.gov (United States)

    1988-12-01

    Communications and Surveil- lance, IEE, Conference publication n.95, 13-15 Mar. 1973. 2. Y. Karasawa and T. Shiokawa , Characteristics of L-Band Multipath Fading... Shiokawa . Analysis of M-ultipath Fading due to Sea Suface Scattering in Maritime Satellite Communication, Technical Group on Antennas and Propagation. IECE

  6. A Framework for Assessing Soil Moisture Deficit and Crop Water Stress at Multiple Space and Time Scales Under Climate Change Scenarios Using Model Platform, Satellite Remote Sensing, and Decision Support System

    KAUST Repository

    Mohanty, Binayak P.

    2016-11-03

    Better understanding of water cycle at different space–time scales would be a key for sustainable water resources, agricultural production, and ecosystems health in the twenty-first century. Efficient agricultural water management is necessary for sustainability of the growing global population. This warrants better predictive tools for aridity (based on precipitation, temperature, land use, and land cover), root zone (~top 1 m) soil moisture deficit, and crop water stress at farm, county, state, region, and national level, where decisions are made to allocate and manage the water resources. It will provide useful strategies for not only efficient water use but also for reducing potential risk of crop failure due to agricultural drought. Leveraging heavily on ongoing multiscale hydrologic modeling, data assimilation, soil moisture dynamics, and inverse model development research activities, and ongoing Land Data Assimilation (LDAS) and National Climate Assessment (NCA) indexing efforts we are developing a drought assessment framework. The drought assessment platform includes: (1) developing disaggregation methods for extracting various field-scale (1-km or less) climate indicators from the (SMOS, VIIRS, SMAP, AMSR-2) satellite / LDAS-based soil moisture in conjunction with a multimodel simulation–optimization approach using ensemble of Soil Vegetation Atmosphere Transfer, SVAT (Noah, CLM, VIC, Mosaic in LIS) models; (2) predicting farm/field-scale long-term root zone soil moisture status under various land management and climate scenarios for the past decades in hindcast mode and for the next decades in forecast mode across the USA using effective land surface parameters and meteorological input from Global Circulation Model (GCM) outputs; (3) assessing the potential risk of agricultural drought at different space–time scales across the USA based on predicted root zone soil moisture; and (4) evaluating various water management and cropping practices (e

  7. The Mars Exploration Program: Past, Present and Future (?)

    Science.gov (United States)

    Hubbard, Scott

    NASA's Mars Exploration Program was redesigned in 2000, following the twin losses of the Mars Climate Orbiter and Mars Polar Lander in late 1999. The new science based program was grounded in community consensus based priorities and had as its aim understanding Mars as a system. The popular phrase used to describe the goals of the mission sequence was "Follow the Water". A new queue of missions was put in place for the decade 2001 - 2010 and a new community based competitive opportunity, the Mars Scout program, was initiated. The strategic mission implementation has been unchanged since the new program was announced in October 2000. Those projects successfully launched and deployed thus far include Mars Odyssey, the two Mars rovers Spirit and Opportunity, Mars Reconnaissance Obiter and the Phoenix Scout Mission. The final project of the decade, the Mars Science Laboratory, is in the last stages of development with launch slated for the Fall of 2009. The President's budget announced in February 2008 for Fiscal 2009, contained little in the way of definitive objectives for Mars program in the decade 2011-2020 and proposed to reduce the Mars budget drastically over the five year budget period. This paper will review the programmatic and scientific progress thus far in meeting the original objectives as outlined in October 2000. A look ahead to the potential missions and goals for the next decade will be provided with particular emphasis on the status of Mars Sample Return mission. Bibliography: G. Scott Hubbard, Firouz M. Naderi, James B. Garvin, Following the water, the new program for Mars exploration, Acta Astronautica 51(1-9):337-350, 2002.

  8. Satellite-derived estimates of forest leaf area index in southwest Western Australia are not tightly coupled to interannual variations in rainfall: implications for groundwater decline in a drying climate.

    Science.gov (United States)

    Smettem, Keith R J; Waring, Richard H; Callow, John N; Wilson, Melissa; Mu, Qiaozhen

    2013-08-01

    There is increasing concern that widespread forest decline could occur in regions of the world where droughts are predicted to increase in frequency and severity as a result of climate change. The average annual leaf area index (LAI) is an indicator of canopy cover and the difference between the annual maximum and minimum LAI is an indicator of annual leaf turnover. In this study, we analyzed satellite-derived estimates of monthly LAI across forested coastal catchments of southwest Western Australia over a 12 year period (2000-2011) that included the driest year on record for the last 60 years. We observed that over the 12 year study period, the spatial pattern of average annual satellite-derived LAI values was linearly related to mean annual rainfall. However, interannual changes to LAI in response to changes in annual rainfall were far less than expected from the long-term LAI-rainfall trend. This buffered response was investigated using a physiological growth model and attributed to availability of deep soil moisture and/or groundwater storage. The maintenance of high LAIs may be linked to a long-term decline in areal average underground water storage and diminished summer flows, with an emerging trend toward more ephemeral flow regimes.

  9. Modeling the hydrological cycle on Mars

    Directory of Open Access Journals (Sweden)

    Ghada Machtoub

    2012-03-01

    Full Text Available The study provides a detailed analysis of the hydrological cycle on Mars simulated with a newly developed microphysical model, incorporated in a spectral Mars General Circulation Model. The modeled hydrological cycle is compared well with simulations of other global climate models. The simulated seasonal migration ofwater vapor, circulation instability, and the high degree of temporal variability of localized water vapor outbursts are shown closely consistent with recent observations. The microphysical parameterization provides a significant improvement in the modeling of ice clouds evolved over the tropics and major ancient volcanoes on Mars. The most significant difference between the simulations presented here and other GCM results is the level at which the water ice clouds are found. The model findings also support interpretation of observed thermal anomalies in the Martian tropics during northern spring and summer seasons.

  10. The great 2003 perihelic apparition of Mars

    Science.gov (United States)

    Beish, Jeffrey D.; Parker, Donald C.

    2003-02-01

    Mars will approach closer to the Earth during the 2003 apparition than at any other time in over 59,000 years! Always an intriguing world, Mars offers both casual and serious observers many challenges and delights. It also provides astronomers a laboratory to study the atmosphere and surface of another planet, including the behavior of condensates and their effects on its atmosphere and surface. Mars is similar to Earth in that it has four seasons, exhibits global climates, changing weather patterns, annual thawing and growing of polar caps, storm clouds of water ice, dusty winds, and a variety of surface features that predictably change in color and size and appear to shift position over extended periods of time.

  11. Mars secular obliquity change due to the seasonal polar caps

    Science.gov (United States)

    Rubincam, David P.

    1992-01-01

    There is a weak positive feedback mechanism between the astronomy and meteorology of Mars. The mechanism is this: the seasonal waxing and waning polar caps cause small changes in Mars' dynamical flattening. Because the changes in flattening are out of phase with the sun, there is a net annual solar torque on the planet which increases the angle between the equatorial and orbital phanes. On the basis of Viking observations of the present climate and simple atmospheric models of past climates, these seasonal shifts of mass between the atmosphere and polar caps are capable of secularly increasing Mars' obliquity by about 1 or 2 deg since the origin of the solar system. Thus, the climate, driven largely by the axial tilt, reacts back on the planet and slightly enhances the seasons on Mars as time progresses. More sophisticated models will probably not change this result much; therefore this mechanism probably produced only minor changes in Mars' climate. It causes negligible changes in the axial tilt and climate of the earth.

  12. Satellite Communications

    CERN Document Server

    Pelton, Joseph N

    2012-01-01

    The field of satellite communications represents the world's largest space industry. Those who are interested in space need to understand the fundamentals of satellite communications, its technology, operation, business, economic, and regulatory aspects. This book explains all this along with key insights into the field's future growth trends and current strategic challenges. Fundamentals of Satellite Communications is a concise book that gives all of the key facts and figures as well as a strategic view of where this dynamic industry is going. Author Joseph N. Pelton, PhD, former Dean of the International Space University and former Director of Strategic Policy at Intelstat, presents a r

  13. Chasing the Black Smoke: Building Software for CALIPSO Satellite Data to Aid in Tracking and Identifying Sources of Aerosols and their Impact on the Earth's Climate

    Science.gov (United States)

    Mercer, G. A.

    2015-12-01

    The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite is a NASA Earth observation that analyzes aerosol particles suspended in the Earth's atmosphere. Researchers use visualized CALIPSO data to track the global distribution, dispersion, and source of aerosols. There currently exists a tool for displaying CALIPSO data, but this tool does not support needed features for tracking aerosols such as selecting regions of data and sharing those selected regions, making tracking specific airborne objects difficult for researchers. Adding these necessary features to the current CALIPSO visualization tool is difficult, as the tool is written in Interactive Data Language (IDL), a proprietary and obscure language and writing additional features for the tool would require a specialized development team. This topic will focus on release of a new tool for visualization CALIPSO's atmospheric data, or the Visualization of CALIPSO (VOCAL) open source Python program. The talk will explain why VOCAL will serve as the successor to the current visualization tool for CALIPSO data, what new features VOCAL brings to the table for researchers, and how this new tool can further support the tracking and identification of aerosols in the Earth's atmosphere.

  14. Detection of extreme climate events in semi-arid biomes using a combination of near-field and satellite based remote sensing across the New Mexico Elevation Gradient network of flux towers

    Science.gov (United States)

    Litvak, M. E.; Krofcheck, D. J.; Maurer, G.

    2015-12-01

    Semi-arid biomes in the Southwestern U.S. over the past decade have experienced high inter- and intra-annual variability in precipitation and vapor-pressure deficit (VPD), and from recent observations, are particularly vulnerable to both VPD and drought. Given the large land area occupied by semi-arid biomes in the U.S., the ability to quantify how climate extremes alter ecosystem function, in addition to being able to use satellites to remotely detect when these climate extremes occur, is crucial to scale the impact of these events on regional carbon dynamics. In an effort to understand how well commonly employed remote sensing platforms capture the impact of extreme events on semi-arid biomes, we coupled a 9-year record of eddy-covariance measurements made across an elevation/aridity gradient in NM with remote sensing data sets from tower-based phenocams, MODIS and Landsat 7 ETM+. We compared anomalies in air temperature, vapor pressure deficit, and precipitation, to the degree in variability of remote sensing vegetation indices (e.g, NDVI, EVI, 2G-Rbi, LST, etc.), and tower-derived gross primary productivity (GPP), across a range of temporal lags to quantify : 1) how sensitive vegetation indices from various platforms, LST, and carbon uptake are to climate disturbances, and the extremity of the disturbance; 2) how well correlated vegetation indices and tower fluxes are on monthly, seasonal and annual time scales, and if the degree to which they are correlated is related to the extent of climate anomalies during that period; and 3) the lags in the response of both GPP and vegetation indices to climate-anomalies and how well correlated these were on various time scales. Our initial results show differential sensitivities across a range of semi-arid ecosystems to drought and vapor pressure deficit. We see the strongest sensitivity of vegetation indices, and correlations between vegetation indices and tower GPP in the low and high elevation biomes that have a more

  15. Sea level and climate variations

    NARCIS (Netherlands)

    Oerlemans, J.

    1985-01-01

    Review paper, ESA Symposium on Application of Satellite Data to Climate Modelling. Alpbach (Austria) Sea level is an essential component of the climate system, on which many human activities in the coastal zone depend. Climate variations leading to changes in relative sea level are

  16. Mars at Opposition

    Science.gov (United States)

    Riddle, Bob

    2010-01-01

    On January 29, Mars will reach opposition, a point along its orbit around the Sun where Mars will be directly opposite from the Sun in a two-planet and Sun line-up with the Earth in between. At this opposition, the Earth and Mars will be separated by nearly 100 million km. An opposition is similar to a full Moon in that the planet at opposition…

  17. Mars at Opposition

    Science.gov (United States)

    Riddle, Bob

    2010-01-01

    On January 29, Mars will reach opposition, a point along its orbit around the Sun where Mars will be directly opposite from the Sun in a two-planet and Sun line-up with the Earth in between. At this opposition, the Earth and Mars will be separated by nearly 100 million km. An opposition is similar to a full Moon in that the planet at opposition…

  18. Advanced Communication and Networking Technologies for Mars Exploration

    Science.gov (United States)

    Bhasin, Kul; Hayden, Jeff; Agre, Jonathan R.; Clare, Loren P.; Yan, Tsun-Yee

    2001-01-01

    Next-generation Mars communications networks will provide communications and navigation services to a wide variety of Mars science vehicles including: spacecraft that are arriving at Mars, spacecraft that are entering and descending in the Mars atmosphere, scientific orbiter spacecraft, spacecraft that return Mars samples to Earth, landers, rovers, aerobots, airplanes, and sensing pods. In the current architecture plans, the communication services will be provided using capabilities deployed on the science vehicles as well as dedicated communication satellites that will together make up the Mars network. This network will evolve as additional vehicles arrive, depart or end their useful missions. Cost savings and increased reliability will result from the ability to share communication services between missions. This paper discusses the basic architecture that is needed to support the Mars Communications Network part of NASA's Space Science Enterprise (SSE) communications architecture. The network may use various networking technologies such as those employed in the terrestrial Internet, as well as special purpose deep-space protocols to move data and commands autonomously between vehicles, at disparate Mars vicinity sites (on the surface or in near-Mars space) and between Mars vehicles and earthbound users. The architecture of the spacecraft on-board local communications is being reconsidered in light of these new networking requirements. The trend towards increasingly autonomous operation of the spacecraft is aimed at reducing the dependence on resource scheduling provided by Earth-based operators and increasing system fault tolerance. However, these benefits will result in increased communication and software development requirements. As a result, the envisioned Mars communications infrastructure requires both hardware and protocol technology advancements. This paper will describe a number of the critical technology needs and some of the ongoing research

  19. Mars Museum Visualization Alliance

    Science.gov (United States)

    Sohus, A. M.; Viotti, M. A.; de Jong, E. M.

    2004-11-01

    The Mars Museum Visualization Alliance is a collaborative effort funded by the Mars Public Engagement Office and supported by JPL's Informal Education staff and the Solar System Visualization Project to share the adventure of exploration and make Mars a real place. The effort started in 2002 with a small working group of museum professionals to learn how best to serve museum audiences through informal science educators. By the time the Mars Exploration Rovers landed on Mars in January 2004, over 100 organizations were partners in the Alliance, which has become a focused community of Mars educators. The Alliance provides guaranteed access to images, information, news, and resources for use by the informal science educators with their students, educators, and public audiences. Thousands of people have shared the adventure of exploring Mars and now see it as a real place through the efforts of the Mars Museum Visualization Alliance partners. The Alliance has been lauded for "providing just the right inside track for museums to do what they do best," be that webcasts, live presentations with the latest images and information, high-definition productions, planetarium shows, or hands-on educational activities. The Alliance is extending its mission component with Cassini, Genesis, Deep Impact, and Stardust. The Mars Exploration and Cassini Programs, as well as the Genesis, Deep Impact, and Stardust Projects, are managed for NASA by the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California.

  20. Erosionsrinnen auf dem Mars

    OpenAIRE

    Reiß, Dennis Emil

    2010-01-01

    The work presented here analyses gullies on Mars using high resolution images (Mars Orbiter Camera – MOC) of the Mars Global Surveyor Mission (MGS). Gullies on Earth are formed by debris flows, a mass movement in which water is involved. It is assumed that gully features on Mars are young and therefore they could indicate the presence of liquid water in the recent past. The main focus of this work lies in a morphological analysis, a global mapping of their distribution and a determination of ...

  1. Digital cartography of Mars

    Science.gov (United States)

    Batson, R. M.

    1987-01-01

    A medium-resolution Digital Image Model (DIM) of Mars is being compiled. A DIM is a mosaic of radiometrically corrected, photometrically modelled spacecraft images displaying accurate reflectance properties at uniform resolution, and geometrically tied to the best available control. The Mars medium-resolution DIM contains approximately 4700 Viking Orbiter image frames that were used to compile the recently completed 1:2,000,000-scale controlled photomosaic series of Mars. This DIM provides a planimetric control base to which all other Mars maps will be registered. A similar control base of topographic elevations (Digital Terrain Model, or DTM) is also being compiled. These products are scheduled for completion in 1989.

  2. Seasonal erosion and restoration of Mars' northern polar dunes

    Science.gov (United States)

    Hansen, C.J.; Bourke, M.; Bridges, N.T.; Byrne, S.; Colon, C.; Diniega, S.; Dundas, C.; Herkenhoff, K.; McEwen, A.; Mellon, M.; Portyankina, G.; Thomas, N.

    2011-01-01

    Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO 2 seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.

  3. Satellite Geomagnetism

    DEFF Research Database (Denmark)

    Olsen, Nils; Stolle, Claudia

    2012-01-01

    Observations of Earth’s magnetic field from space began more than 50 years ago. A continuous monitoring of the field using low Earth orbit (LEO) satellites, however, started only in 1999, and three satellites have taken highprecision measurements of the geomagnetic field during the past decade...... ability to characterize and understand the many sources that contribute to Earth’s magnetic field. In this review, we summarize investigations of Earth’s interior and environment that have been possible through the analysis of high-precision magnetic field observations taken by LEO satellites........ The unprecedented time-space coverage of their data opened revolutionary new possibilities for monitoring, understanding, and exploring Earth’s magnetic field. In the near future, the three-satellite constellation Swarm will ensure continuity of such measurement and provide enhanced possibilities to improve our...

  4. Satellite (Natural)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    In its most general sense, any celestial object in orbit around a similar larger object. Thus, for example, the Magellanic Clouds are satellite galaxies of our own Milky Way galaxy. Without qualification, the term is used to mean a body in orbit around a planet; an alternative term is moon. The term natural satellite distinguishes these bodies from artificial satellites—spacecraft placed in orbi...

  5. Cemented Volcanic Soils, Martian Spectra and Implications for the Martian Climate

    Science.gov (United States)

    Bishop, J. L.; Schiffman, P.; Drief, A.; Southard, R. J.

    2004-03-01

    Cemented volcanic crusts are studied to learn about their composition, formation processes, and implications for climate interactions with the surface on Mars. Such carbonate, sulfate and opal crusts may be present in cemented soil units on Mars.

  6. Satellite-derived NDVI, LST, and climatic factors driving the distribution and abundance of Anopheles mosquitoes in a former malarious area in northwest Argentina.

    Science.gov (United States)

    Dantur Juri, María Julia; Estallo, Elizabet; Almirón, Walter; Santana, Mirta; Sartor, Paolo; Lamfri, Mario; Zaidenberg, Mario

    2015-06-01

    Distribution and abundance of disease vectors are directly related to climatic conditions and environmental changes. Remote sensing data have been used for monitoring environmental conditions influencing spatial patterns of vector-borne diseases. The aim of this study was to analyze the effect of the Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS), and climatic factors (temperature, humidity, wind velocity, and accumulated rainfall) on the distribution and abundance of Anopheles species in northwestern Argentina using Poisson regression analyses. Samples were collected from December, 2001 to December, 2005 at three localities, Aguas Blancas, El Oculto and San Ramón de la Nueva Orán. We collected 11,206 adult Anopheles species, with the major abundance observed at El Oculto (59.11%), followed by Aguas Blancas (22.10%) and San Ramón de la Nueva Orán (18.79%). Anopheles pseudopunctipennis was the most abundant species at El Oculto, Anopheles argyritarsis predominated in Aguas Blancas, and Anopheles strodei in San Ramón de la Nueva Orán. Samples were collected throughout the sampling period, with the highest peaks during the spring seasons. LST and mean temperature appear to be the most important variables determining the distribution patterns and major abundance of An. pseudopunctipennis and An. argyritarsis within malarious areas. © 2015 The Society for Vector Ecology.

  7. 15 CFR 950.8 - Satellite Data Services Division (SDSD).

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Satellite Data Services Division (SDSD... THE ENVIRONMENTAL DATA SERVICE ENVIRONMENTAL DATA AND INFORMATION § 950.8 Satellite Data Services Division (SDSD). The Satellite Data Services Division of the EDIS National Climatic Center...

  8. Satellite observations of ground water changes in New Mexico

    Science.gov (United States)

    In 2002 NASA launched the Gravity Recovery and Climate Experiment (GRACE) satellite mission. GRACE consists of two satellites with a separation of about 200 km.  By accurately measuring the separation between the twin satellites, the differences in the gravity field can be determined. Monthly observ...

  9. Microscope on Mars

    Science.gov (United States)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  10. Microscope on Mars

    Science.gov (United States)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  11. Quantitative Cloud Analysis using Meteorological Satellites

    NARCIS (Netherlands)

    Feijt, A.J.

    2000-01-01

    This thesis is about observations of clouds from satellite and ground based instruments. The aim is to reconstruct the three dimensional cloud distributions. This information is used both in climate research and operational meteorological applications. In climate research, cloud observations provide

  12. Pump Fed Propulsion for Mars Ascent and Other Challenging Maneuvers

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J C

    2007-05-09

    Returning Mars geology samples to Earth within science mission budgets requires a miniature launch vehicle (100-200 kg) for ascending from Mars to an orbital rendezvous. A Mars Ascent Vehicle must deliver a velocity change exceeding 4 km/s within minutes, entirely outside the capabilities of satellite propulsion. A possible solution is to scale down liquid launch vehicle principles to achieve stage propellant mass fractions near 90 percent. Feeding a high-pressure engine from thin-walled low pressure tanks permits stage hardware to be sufficiently lightweight and compact, if very high performance pumps can be made available. NASA's Mars Technology Program has funded refinement and testing of a miniature piston pump, powered by reacted propellant. A pump-fed bipropellant rocket stage remains to be developed. The technology could also benefit other future lunar and planetary science programs.

  13. Flux-gate magnetometer for Mars exploration

    Science.gov (United States)

    Zhao, Hua; Zhu, G. W.; Yu, P.; Wang, J. D.; Yu, M. F.; Li, L.; Sun, Y. Q.; Chen, S. W.; Liao, H. Z.; Zhou, B.; Feng, Y. Y.

    2008-10-01

    A micro-satellite, Yinghuo-1, would be launched with Russian spacecraft, Phobos-Grunt in October, 2009 to investigate the space environment around Mars. YH-1 and Phobos-Grunt forms a two-point measurement configuration in the Martian space environment. YH-1 and Phobos-Grunt are equipped with similar magnetic field and plasma detecting payload on two spacecraft would give some coordinated exploration around Mars. YH-1 would orbit Mars with periapsis of 800 km above the Martian surface, and apoapsis about 80000km to the center of Mars. The orbit inclination is in the range of 0~7° to the Martian equator. A flux-gate type magnetometer, with two tri-axial sensors, is developed for YH-1 spacecraft. Two sensors are mounted on one-side of the deployable solar panel with a radial separation about 45cm to function as a gradiometer to minimize the affects of platform remanence. The dynamic range of the magnetometer is +/-256nT with a 16-bit ADC converter, and the noise level is better than 0.01nT/√Hz, to measure three-component magnetic field from DC to 10Hz. Flux-gate magnetometer would work together with the Plasma Package onboard of YH-1 to investigate the Martian bow shock, magnetosheath, magnetic pileup region (MPR). A detail description of the flux-gate magnetometer is presented in this paper, with test and calibration results.

  14. Satellite-Derived Aerosol Climate Data Records in the ESA Aerosol_Cci Project: From ERS-2, Envisat to Sentinel-3

    Science.gov (United States)

    de Leeuw, Gerrit; Holzer-Popp, Thomas; North, Peter R. J.; Heckel, Andreas; Pinnock, Simon

    2015-12-01

    With the focus of Sentinel-3 on ocean applications and services, important parts of the payload are the Sea and Land Surface Temperature Radiometer (SLSTR) and the Ocean Land Colour Instrument (OLCI). Apart from Ocean applications, these instruments are also very important for atmospheric observations and in particular for aerosol retrieval. This is the reason why the predecessor instruments AATSR and MERIS have extensively been used in the ESA Climate Change Initiative project Aerosol_cci. In this contribution a brief overview of the current status of the Aerosol_cci project is presented. Full-mission time series of ATSR-2 and AATSR have been processed to provide 17 years of global aerosol information. Selected examples of recent achievements are presented. The experience with ATSR-2, AATSR and MERIS will be used to continue the current time series with SLSTR and OLCI.

  15. Vegetation Phenology and Intensity as a Function of Climate and River Flows for an Ephemeral Desert River, 2000 to 2010, Using MODIS Satellite Data

    Science.gov (United States)

    Nguyen, U.; Nagler, P. L.; Glenn, E. P.; Van Riper, C., III

    2011-12-01

    The San Pedro river, located along Sonoran and Chihuahuan desert, is one of the most biologically diverse ecosystems in the Rocky mountains of the Southwestern United States. Vegetation dynamics related to seasonal changes may affect the life and migration of many wildlife species. Furthermore, vegetation density is related to surface flows in the river and depth to groundwater, which vary year to year. The MODIS Vegetation Index products (EVI and NDVI) were used to monitor vegetation dynamics during 10 years (2000-2010) to examine the impact of climatic conditions (such as temperature from LST, precipitation from PRISM and rive flows from gaga data) on the onset of greenness, senescence, and maximum vegetation density. The phenology profiles from time series data and relationships between vegetation index and temperature not only show seasonal changes but also respond to moisture stress on vegetation in the riparian areas of the San Pedro River.

  16. The fluvial history of Mars.

    Science.gov (United States)

    Carr, Michael H

    2012-05-13

    River channels and valleys have been observed on several planetary bodies in addition to the Earth. Long sinuous valleys on Venus, our Moon and Jupiter's moon Io are clearly formed by lava, and branching valleys on Saturn's moon Titan may be forming today by rivers of methane. But by far the most dissected body in our Solar System apart from the Earth is Mars. Branching valleys that in plan resemble terrestrial river valleys are common throughout the most ancient landscapes preserved on the planet. Accompanying the valleys are the remains of other indicators of erosion and deposition, such as deltas, alluvial fans and lake beds. There is little reason to doubt that water was the erosive agent and that early in Mars' history, climatic conditions were very different from the present cold conditions and such that, at least episodically, water could flow across the surface. In addition to the branching valley networks, there are large flood features, termed outflow channels. These are similar to, but dwarf, the largest terrestrial flood channels. The consensus is that these channels were also cut by water although there are other possibilities. The outflow channels mostly postdate the valley networks, although most are still very ancient. They appear to have formed at a time when surface conditions were similar to those that prevail today. There is evidence that glacial activity has modified some of the water-worn valleys, particularly in the 30-50° latitude belts, and ice may also be implicated in the formation of geologically recent, seemingly water-worn gullies on steep slopes. Mars also has had a long volcanic history, and long, sinuous lava channels similar to those on the Moon and Venus are common on and around the large volcanoes. These will not, however, be discussed further; the emphasis here is on the effects of running water on the evolution of the surface.

  17. Evaluation of Antarctic polar stratospheric clouds data obtained by ground based lidars (at Dome C, McMurdo and Dumont D'Urville) and the satellite based CALIOP lidar system versus a subset of CCMVAL-2 chemistry-climate models.

    Science.gov (United States)

    Snels, Marcel; Fierli, Federico; de Muro, Mauro; Cagnazzo, Chiara; Cairo, Francesco; Di Liberto, Luca

    2016-04-01

    Polar stratospheric clouds play an important role in the ozone depletion process in polar regions and are thus strongly linked to climate changes. Long term observations are needed to monitor the presence of PSCs and to compare to climate models. The last decades PSCs in Antarctica have been observed by using the CALIOP lidar system on the CALIPSO satellite and by ground based lidars at Dumont D'Urville, McMurdo, Casey, and since 2014 at Dome C. We evaluate the Antarctic PSC observational databases of CALIPSO and the ground-based lidars of NDACC (Network for Detection of Atmospheric Composition Changes) located in McMurdo and Dumont D'Urville and Dome C stations and provide a process-oriented evaluation of PSC in a subset of CCMVAL-2 chemistry-climate models. Lidar observatories have a decadal coverage, albeit with discontinuities, spanning from 1992 to today hence offering a unique database. A clear issue is the representativeness of ground-based long-term data series of the Antarctic stratosphere conditions that may limit their value in climatological studies and model evaluation. The comparison with the CALIPSO observations with a global coverage is, hence, a key issue. In turn, models can have a biased representation of the stratospheric conditions and of the PSC microphysics leading to large discrepancies in PSC occurrence and composition. Point-to-point comparison is difficult due to sparseness of the database and to intrinsic differences in spatial distribution between models and observations. However, a statistical analysis of PSC observations shows a satisfactory agreement between ground-based and satellite borne-lidar. The differences may be attributed to averaging processes for data with a bad signal to noise ratio, which tends to smear out the values of the optical parameters. Data from some Chemistry Climate models (CCMs) having provided PSC surface areas on daily basis have been evaluated using the same diagnostic type that may be derived CALIPSO (i

  18. Scientific Satellites

    Science.gov (United States)

    1967-01-01

    followed Hale’s into orbit. In 1879, Jules Verne wrote about launching small satellites with a gun possessing a muzzle velocity of 10 000 m/sec (ref. 3...was activated in 1950.11 It was located only a few tens of miles from the spot where Jules Verne had his Baltimore Gun Club fire a manned projectile to...principle, satellites can be launched by a single impulse applied at the Earth’s surface-say, with a large cannon, & la Jules Verne (sec. 8-3). In

  19. A Mars Exploration Discovery Program

    Science.gov (United States)

    Hansen, C. J.; Paige, D. A.

    2000-07-01

    The Mars Exploration Program should consider following the Discovery Program model. In the Discovery Program a team of scientists led by a PI develop the science goals of their mission, decide what payload achieves the necessary measurements most effectively, and then choose a spacecraft with the capabilities needed to carry the payload to the desired target body. The primary constraints associated with the Discovery missions are time and money. The proposer must convince reviewers that their mission has scientific merit and is feasible. Every Announcement of Opportunity has resulted in a collection of creative ideas that fit within advertised constraints. Following this model, a "Mars Discovery Program" would issue an Announcement of Opportunity for each launch opportunity with schedule constraints dictated by the launch window and fiscal constraints in accord with the program budget. All else would be left to the proposer to choose, based on the science the team wants to accomplish, consistent with the program theme of "Life, Climate and Resources". A proposer could propose a lander, an orbiter, a fleet of SCOUT vehicles or penetrators, an airplane, a balloon mission, a large rover, a small rover, etc. depending on what made the most sense for the science investigation and payload. As in the Discovery program, overall feasibility relative to cost, schedule and technology readiness would be evaluated and be part of the selection process.

  20. Strong Coupling Between Winter Climatic Fluctuations and Development of Phytoplankton in the Deep Lakes South of the Alps Assessed Using Long-Term in Situ and Satellite Temperature Data

    Science.gov (United States)

    Salmaso, N.; Pareeth, S.; Cerasino, L.; Neteler, M.

    2014-12-01

    Recent investigations showed that the winter climate in the lake district south of the Alps was strongly affected by specific prominent modes of low-frequency atmospheric variability relevant for the Mediterranean area (namely the East Atlantic pattern, EA, and the Eastern Mediterranean Pattern, EMP). In Lake Garda, the winter interannual fluctuations of EA and EMP triggered a long-chain of causally-linked effects on the physical structure of the lake and biological communities. Since 1991, and contrary to the summer months, the long-term increase of the mean winter water temperatures in the mixolimnion (0-50 m, ca. 0.01 °C yr-1) was statistically not-significant, coinciding, as confirmed by longer annual 1971-2014 series, with a period of relatively winter stable temperatures. Superimposed to the long-term trend, the deep hypolimnion showed different periods of warming caused by a downward transport of heat by turbulent diffusion during stratification. These phases were terminated by sudden cooling and overturn during harsh winters associated with negative EA and positive EMP values. The long term saw tooth temperature dynamics had a strong impact on the transport of hypolimnetic nutrients towards the surface, fuelling the development of eutrophic species, namely toxic cyanobacteria during the summer months. Other changes in the trophic webs included modifications in the phenology of the dominant zooplankton cladocerans. In the subalpine lake district, changes were documented not only at the level of species, but also genotypes, with a positive selection of cyanobacterial strains with strong gas-vesicles (i.e. best adapted to higher hydrostatic pressures) in lakes experiencing deep mixing. The study of the effects of climatic fluctuations and long-term changes was based on monthly field data. In this work, the evaluation will be further investigated also using high resolution satellite temperature data recorded using Moderate-resolution Imaging Spectroradiometer

  1. Mars surface albedo and changes

    CERN Document Server

    Vincendon, Mathieu; Altieri, Francesca; Ody, Anouck

    2014-01-01

    The pervasive Mars dust is continually transported between surface and atmosphere. When on the surface, dust increases the albedo of darker underlying rocks and regolith, which modifies climate energy balance and must be quantified. Remote observation of surface albedo absolute value and albedo change is however complicated by dust itself when lifted in the atmosphere. Here we present a method to calculate and map the bolometric solar hemispherical albedo of the Martian surface using the 2004 - 2010 OMEGA imaging spectrometer dataset. This method takes into account aerosols radiative transfer, surface photometry, and instrumental issues such as registration differences between visible and near-IR detectors. Resulting albedos are on average 17% higher than previous estimates for bright surfaces while similar for dark surfaces. We observed that surface albedo changes occur mostly during the storm season due to isolated events. The main variations are observed during the 2007 global dust storm and during the fol...

  2. ExoMars 2016 arrives at Mars

    Science.gov (United States)

    Svedhem, Hakan; Vago, Jorge L.; ExoMars Team

    2016-10-01

    The Trace Gas Orbiter (TGO) and the Schiaparelli Entry, descent and landing Demonstrator Model (EDM) will arrive at Mars on 19 October 2016. The TGO and the EDM are part of the first step of the ExoMars Programme. They will be followed by a Rover and a long lived Surface Platform to be launched in 2020.The EDM is attached to the TGO for the full duration of the cruise to Mars and will be separated three days before arrival at Mars. After separation the TGO will perform a deflection manoeuvre and, on 19 October (during the EDM landing), enter into a highly elliptical near equatorial orbit. TGO will remain in this parking orbit until January 2017, when the orbital plane inclination will be changed to 74 degrees and aerobraking to the final 400 km near circular orbit will start. The final operational orbit is expected to be reached at the end of 2017.The TGO scientific payload consists of four instruments. These are: ACS and NOMAD, both infrared spectrometers for atmospheric measurements in solar occultation mode and in nadir mode, CASSIS, a multichannel camera with stereo imaging capability, and FREND, an epithermal neutron detector for search of subsurface hydrogen. The mass of the TGO is 3700 kg, including fuel. The EDM, with a mass of 600 kg, is mounted on top of the TGO as seen in its launch configuration. The main objective of the EDM is to demonstrate the capability of performing a safe entry, descent and landing on the surface, but it does carry a descent camera and a small battery powered meteorological package that may operate for a few days on the surface.The ExoMars programme is a joint activity by the European Space Agency(ESA) and ROSCOSMOS, Russia. ESA is providing the TGO spacecraft and Schiaparelli (EDM) and two of the TGO instruments and ROSCOSMOS is providing the launcher and the other two TGO instruments. After the arrival of the ExoMars 2020 mission at the surface of Mars, the TGO will handle the communication between the Earth and the Rover and

  3. Beagle 2 and NASA's Mars 2003 Orbiter: A Unique Exobiology Opportunity with an Orbiter

    Science.gov (United States)

    Gibson, Everett K., Jr.; Pillinger, Colin T.; Thatcher, John; Westall, Frances

    2000-01-01

    With the exploration strategy for Mars undergoing reexamination, the opportunity exists for the incorporation of the 60 kg Beagle 2 lander, developed in the United Kingdom for inclusion on ESA's 2003 Mars Express mission, with NASA's Mars 2003 orbiter derived from the Mars Global Orbiter. The combination of Beagle 2 with a Mars orbiter would result in a unique mission which could obtain information on Mars' life, climate and resources both from orbit as well as on the surface of the planet. Beagle 2 has been developed in the LJK for ESA as a low-cost opportunity to study the exobiology of Mars and the spacecraft is in its final stages of manufacture. Only limited modifications to the Beagle 2 package would be required for inclusion on NASA's Mars 2003 orbiter. With the ESA Mars Express mission launch in 2003 and a potential NASA Mars orbiter in 2003, both Beagle 2 landers on Mars would offer a low-cost, decreased risk and increased science return opportunity for the exploration of Mars at two distinct geologically interesting sites.

  4. MARS: a status report

    Energy Technology Data Exchange (ETDEWEB)

    Tribble, R.E.; Gagliardi, C.A.; Liu, W. (Cyclotron Inst., Texas A and M Univ., College Station (USA))

    1991-05-01

    We are building a momentum achromat recoil spectrometer (MARS) for use with the new K500 superconducting cyclotron at Texas A and M University. MARS uses a unique optical design utilizing two dispersive planes to combine a momemtum achromat with a recoil mass spectrometer. This configuration makes MARS applicable to a broad range of nuclear reaction studies utilizing inverse kinematics. It also leads to a system that is well matched to the range of secondary particle energies that will be produced in reactions with K500 beam. MARS will have a typical mass resolution of {delta}M/M{approx equal}1/300, with an energy acceptance of {+-}9% {Delta}E/E and a geometric solid angle of up to 9 msr. A beam swinger system will alow reaction products in the angular range 0deg to 30deg to be studied. MARS will be used to study both the excited states and decay properties of very proton- and neutron-rich nuclei. MARS will also be used to provide a reaction mechanism filter to assist investigations of the dynamics of heavy ion collisions and to produce secondary radioactive beams for reaction and spectroscopic studies of particular interest for nuclear astrophysics. We briefly describe the design of MARS, give a status report on its construction and an overview of the scientific program planned for it. (orig.).

  5. Deep Space Climate Observatory (DSCOVR)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Deep Space Climate ObserVatoRy (DSCOVR) satellite is a NOAA operated asset located at the first Lagrange point (L1). This places it approximately 1% of the...

  6. Mars Observer's costly solitude

    Science.gov (United States)

    Travis, John

    1993-09-01

    An evaluation is presented of the ramifications of the loss of contact with the Mars Observer spacecraft in August, 1993; the Observer constituted the first NASA mission to Mars in 17 years. It is noted that most, if not all of the scientists involved with the mission will have to find alternative employment within 6 months. The loss of the Observer will leave major questions concerning the geologic history of Mars, and its turbulent atmospheric circulation, unanswered. A detailed account of the discovery of the loss of communications, the unsuccessful steps taken to rectify the problem, and the financial losses incurred through the failure of the mission, are also given.

  7. Glacial Meltwater as a Source of Amorphous Silica on Early Mars

    Science.gov (United States)

    Rutledge, A. M.; Horgan, B.; Havig, J. R.; Rampe, E. B.; Scudder, N. A.; Hamilton, T. L.

    2017-10-01

    Cold-climate silica cycling on mafic volcanics due to glacial meltwater alteration is a significant terrestrial weathering process. Amorphous silica deposits on Mars could be interpreted as mineralogical evidence for past ice sheet melt.

  8. Development of a Climate Record of Tropospheric and Stratospheric Column Ozone from Satellite Remote Sensing: Evidence of an Early Recovery of Global Stratospheric Ozone

    Science.gov (United States)

    Ziemke, Jerald R.; Chandra, Sushil

    2012-01-01

    Ozone data beginning October 2004 from the Aura Ozone Monitoring Instrument (OMI) and Aura Microwave Limb Sounder (MLS) are used to evaluate the accuracy of the Cloud Slicing technique in effort to develop long data records of tropospheric and stratospheric ozone and for studying their long-term changes. Using this technique, we have produced a 32-yr (1979-2010) long record of tropospheric and stratospheric column ozone from the combined Total Ozone Mapping Spectrometer (TOMS) and OMI. Analyses of these time series suggest that the quasi-biennial oscillation (QBO) is the dominant source of inter-annual variability of stratospheric ozone and is clearest in the Southern Hemisphere during the Aura time record with related inter-annual changes of 30- 40 Dobson Units. Tropospheric ozone for the long record also indicates a QBO signal in the tropics with peak-to-peak changes varying from 2 to 7 DU. The most important result from our study is that global stratospheric ozone indicates signature of a recovery occurring with ozone abundance now approaching the levels of year 1980 and earlier. The negative trends in stratospheric ozone in both hemispheres during the first 15 yr of the record are now positive over the last 15 yr and with nearly equal magnitudes. This turnaround in stratospheric ozone loss is occurring about 20 yr earlier than predicted by many chemistry climate models. This suggests that the Montreal Protocol which was first signed in 1987 as an international agreement to reduce ozone destroying substances is working well and perhaps better than anticipated.

  9. Development of a climate record of tropospheric and stratospheric column ozone from satellite remote sensing: evidence of an early recovery of global stratospheric ozone

    Directory of Open Access Journals (Sweden)

    J. R. Ziemke

    2012-07-01

    Full Text Available Ozone data beginning October 2004 from the Aura Ozone Monitoring Instrument (OMI and Aura Microwave Limb Sounder (MLS are used to evaluate the accuracy of the Cloud Slicing technique in effort to develop long data records of tropospheric and stratospheric ozone and for studying their long-term changes. Using this technique, we have produced a 32-yr (1979–2010 long record of tropospheric and stratospheric column ozone from the combined Total Ozone Mapping Spectrometer (TOMS and OMI. Analyses of these time series suggest that the quasi-biennial oscillation (QBO is the dominant source of inter-annual variability of stratospheric ozone and is clearest in the Southern Hemisphere during the Aura time record with related inter-annual changes of 30–40 Dobson Units. Tropospheric ozone for the long record also indicates a QBO signal in the tropics with peak-to-peak changes varying from 2 to 7 DU. The most important result from our study is that global stratospheric ozone indicates signature of a recovery occurring with ozone abundance now approaching the levels of year 1980 and earlier. The negative trends in stratospheric ozone in both hemispheres during the first 15 yr of the record are now positive over the last 15 yr and with nearly equal magnitudes. This turnaround in stratospheric ozone loss is occurring about 20 yr earlier than predicted by many chemistry climate models. This suggests that the Montreal Protocol which was first signed in 1987 as an international agreement to reduce ozone destroying substances is working well and perhaps better than anticipated.

  10. Mars' core and magnetism.

    Science.gov (United States)

    Stevenson, D J

    2001-07-12

    The detection of strongly magnetized ancient crust on Mars is one of the most surprising outcomes of recent Mars exploration, and provides important insight about the history and nature of the martian core. The iron-rich core probably formed during the hot accretion of Mars approximately 4.5 billion years ago and subsequently cooled at a rate dictated by the overlying mantle. A core dynamo operated much like Earth's current dynamo, but was probably limited in duration to several hundred million years. The early demise of the dynamo could have arisen through a change in the cooling rate of the mantle, or even a switch in convective style that led to mantle heating. Presently, Mars probably has a liquid, conductive outer core and might have a solid inner core like Earth.

  11. Mars Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA’s Mars Exploration Program (MEP) calls for a series of highly ambitious missions over the next decade and beyond. The overall goals of the MEP must be...

  12. Mars Rover Photos API

    Data.gov (United States)

    National Aeronautics and Space Administration — This API is designed to collect image data gathered by NASA's Curiosity, Opportunity, and Spirit rovers on Mars and make it more easily available to other...

  13. Internal constitution of Mars.

    Science.gov (United States)

    Anderson, D. L.

    1972-01-01

    Models of the internal structure of Mars consistent with the mass, radius and moment of inertia of the planet are constructed. The models assume that the radius of the core is between 0.36 and 0.60 of the radius of the planet, that the zero-pressure density of the mantle is between 3.54 and 3.49 g/cu cm, and that the planet contains 25 to 28% iron. Meteorite models of Mars containing 25 wt % iron and 12 wt % core are also proposed. It is maintained that Mars in contrast to the earth is an incompletely differentiated planet with a core substantially richer in sulfur than the core of the earth. The absence of a magnetic field on Mars is possibly linked with lack of lunar precessional torque and the small size and high resistivity of the Martian core.

  14. Transient reducing greenhouse warming on early Mars

    Science.gov (United States)

    Wordsworth, R.; Kalugina, Y.; Lokshtanov, S.; Vigasin, A.; Ehlmann, B.; Head, J.; Sanders, C.; Wang, H.

    2017-01-01

    The evidence for abundant liquid water on early Mars despite the faint young Sun is a long-standing problem in planetary research. Here we present new ab initio spectroscopic and line-by-line climate calculations of the warming potential of reduced atmospheres on early Mars. We show that the strength of both CO2-H2 and CO2-CH4 collision-induced absorption (CIA) has previously been significantly underestimated. Contrary to previous expectations, methane could have acted as a powerful greenhouse gas on early Mars due to CO2-CH4 CIA in the critical 250-500 cm-1 spectral window region. In atmospheres of 0.5 bar CO2 or more, percent levels of H2 or CH4 raise annual mean surface temperatures by tens of degrees, with temperatures reaching 273 K for pressures of 1.25-2 bars and 2-10% of H2 and CH4. Methane and hydrogen produced following aqueous alteration of Mars' crust could have combined with volcanically outgassed CO2 to form transient atmospheres of this composition 4.5-3.5 Ga. Our results also suggest that inhabited exoplanets could retain surface liquid water at significant distances from their host stars.

  15. Transient reducing greenhouse warming on early Mars

    CERN Document Server

    Wordsworth, Robin; Lokshtanov, Sergei; Vigasin, Andrei; Ehlmann, Bethany; Head, James; Sanders, Cecilia; Wang, Huize

    2016-01-01

    The evidence for abundant liquid water on early Mars despite the faint young Sun is a long-standing problem in planetary research. Here we present new ab initio spectroscopic and line-by-line climate calculations of the warming potential of reduced atmospheres on early Mars. We show that the strength of both CO2-H2 and CO2-CH4 collision-induced absorption (CIA) has previously been significantly underestimated. Contrary to previous expectations, methane could have acted as a powerful greenhouse gas on early Mars due to CO2-CH4 CIA in the critical 250-500 cm^-1 spectral window region. In atmospheres of 0.5 bar CO2 or more, percent levels of H2 or CH4 raise annual mean surface temperatures by tens of degrees, with temperatures reaching 273 K for pressures of 1.25-2 bar and 2-10% of H2 and CH4. Methane and hydrogen produced following aqueous alteration of Mars' crust could have combined with volcanically outgassed CO2 to form transient atmospheres of this composition 4.5-3.5 Ga. This scenario for the late Noachia...

  16. A Mars 1984 mission

    Science.gov (United States)

    1977-01-01

    Mission objectives are developed for the next logical step in the investigation of the local physical and chemical environments and the search for organic compounds on Mars. The necessity of three vehicular elements: orbiter, penetrator, and rover for in situ investigations of atmospheric-lithospheric interactions is emphasized. A summary report and committee recommendations are included with the full report of the Mars Science Working Group.

  17. Status of MARS Code

    Energy Technology Data Exchange (ETDEWEB)

    N.V. Mokhov

    2003-04-09

    Status and recent developments of the MARS 14 Monte Carlo code system for simulation of hadronic and electromagnetic cascades in shielding, accelerator and detector components in the energy range from a fraction of an electronvolt up to 100 TeV are described. these include physics models both in strong and electromagnetic interaction sectors, variance reduction techniques, residual dose, geometry, tracking, histograming. MAD-MARS Beam Line Build and Graphical-User Interface.

  18. Why exobiology on Mars?

    Science.gov (United States)

    Brack, A.

    1996-11-01

    Processing of organic molecules by liquid water was probably an essential requirement towards the emergence of terrestrial primitive life. According to Oparin's hypothesis, organic building blocks required for early life were produced from simple organic molecules formed in a primitive reducing atmosphere. Geochemists favour now a less reducing atmosphere dominated by carbon dioxide. In such an atmosphere very few building blocks are formed. Import of extra-terrestrial organic molecules may represent an alternative supply. Experimental support for such an alternative scenario is examined in comets, meteorites and micrometeorites. The early histories of Mars and Earth clearly show similarities. Liquid water was once stable on the surface of Mars attesting the presence of an atmosphere capable of deccelerating C-rich micrometeorites. Therefore, primitive life may have developed on Mars as well. Liquid water disappeared from the surface of Mars very early, about 3.8 Ga ago. The Viking missions did not find, at the surface of the Martian soil, any organic molecules or clear-cut evidence for microbial activities such as photo-synthesis, respiration or nutrition. The results can be explained referring to an active photochemistry of Martian soil driven by the high influx of solar UV. These experiments do not exclude the existence of organic molecules and fossils of micro-organisms which developed on early Mars until liquid water disappeared. Mars may store below its surface some well preserved clues of a still hypothetical primitive life.

  19. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-11-27

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of Special Applications, in support of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. Presented at the 40th Congress of the IAF, Oct. 7-13, 1989 in Torremolinos, Malaga-Spain. The paper describes the design and analysis of Radioisotope Thermoelectric Generators (RTGs) for powering the Mars Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space for the U.S. DOE in support of the JPL MRSR Project. The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It summarizes the baseline RTG's mass breakdown, and presents a detailed description of its thermal, thermoelectric, and electrical analysis. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments. It provides a basis for selecting the optimum strategy for meeting the Mars Rover design goals with minimal programmatic risk and cost. Cross Reference CID #7135 dated 10/1989. There is a duplicate copy. This document is not relevant to the OSTI Library. Do not send.

  20. Clouds over Mars!

    Science.gov (United States)

    1997-01-01

    This is the first color image ever taken from the surface of Mars of an overcast sky. Featured are pink stratus clouds coming from the northeast at about 15 miles per hour (6.7 meters/second) at an approximate height of ten miles (16 kilometers) above the surface. The clouds consist of water ice condensed on reddish dust particles suspended in the atmosphere. Clouds on Mars are sometimes localized and can sometimes cover entire regions, but have not yet been observed to cover the entire planet. The image was taken about an hour and forty minutes before sunrise by the Imager for Mars Pathfinder (IMP) on Sol 16 at about ten degrees up from the eastern Martian horizon.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages and Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  1. SHERLOC: An investigation for Mars 2020

    Science.gov (United States)

    Beegle, Luther; Bhartia, Rohit; SHERLOC Science Team

    2016-10-01

    The next rover to explore Mars, currently known as Mars2020, is in development for a 2020 launch. The primary goal of the mission is to better understand the geologic and climate history of Mars including the identification of potential signs of past life on Mars. Samples will be characterized by the Mars2020 payload elements. Samples with high science interest will then be collected and stored by the rover for potential return to the earth for analysis in terrestrial laboratories.As part of the payload, NASA selected the Scanning Habitable Environments with Raman & Luminescence for Organics and Chemicals (SHERLOC) investigation. SHERLOC consists of a Deep UV (DUV) native fluorescence and resonance Raman spectrometer that includes a built-to-print version of the Mars Hand Lens Imager (MAHLI) instrument on the Mars Science Laboratory (MSL). It utilizes a DUV laser to generate characteristic Raman and fluorescence photons from a targeted spot. These spectral features are resolvable when a high-radiance, narrow line-width, laser source illuminates a sample. In fluorescence, the incident photons are absorbed and re-emitted at a longer wavelength. Typical fluorescence cross-sections are 104 greater than traditional Raman, enabling the detection of sub-picograms levels of aromatic organic compounds. The DUV laser is co-boresighted to a context imager and integrated into an autofocusing/scanning optical system that allows us to correlate spectral signatures to surface textures, morphology and visible features. An internal scanning mirror enables the generation of maps that allow for the identification of spatially resolved organic structure.SHERLOC's science goals include the detection and classification organics and astrobiologically relevant minerals on the surface and near subsurface of Mars. It is capable of organic sensitivity of 10-5 to 10-6 w/w over the entire observation region of 7 mm x 7 mm. It is capable of alaphatic organic sensitivity of 10-2 to 10-4 w

  2. Eight-year Climatology of Dust Optical Depth on Mars

    CERN Document Server

    Montabone, L; Millour, E; Wilson, R J; Lewis, S R; Cantor, B A; Kass, D; Kleinboehl, A; Lemmon, M; Smith, M D; Wolff, M J

    2014-01-01

    We have produced a multiannual climatology of airborne dust from Martian year 24 to 31 using multiple datasets of retrieved or estimated column optical depths. The datasets are based on observations of the Martian atmosphere from April 1999 to July 2013 made by different orbiting instruments: the Thermal Emission Spectrometer (TES) aboard Mars Global Surveyor, the Thermal Emission Imaging System (THEMIS) aboard Mars Odyssey, and the Mars Climate Sounder (MCS) aboard Mars Reconnaissance Orbiter (MRO). The procedure we have adopted consists of gridding the available retrievals of column dust optical depth (CDOD) from TES and THEMIS nadir observations, as well as the estimates of this quantity from MCS limb observations. Our gridding method calculates averages and uncertainties on a regularly spaced, but possibly incomplete, spatio-temporal grid, using an iterative procedure weighted in space, time, and retrieval uncertainty. In order to evaluate strengths and weaknesses of the resulting gridded maps, we validat...

  3. Mars at Ls 357o

    Science.gov (United States)

    2006-01-01

    31 January 2006 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 357o during a previous Mars year. This month, Mars looks similar, as Ls 357o occurred in mid-January 2006. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn. Season: Northern Winter/Southern Summer

  4. Mars at Ls 324o

    Science.gov (United States)

    2005-01-01

    29 November 2005 This picture is a composite of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily global images acquired at Ls 324o during a previous Mars year. This month, Mars looks similar, as Ls 324o occurred in mid-November 2005. The picture shows the south polar region of Mars. Over the course of the month, additional faces of Mars as it appears at this time of year are being posted for MOC Picture of the Day. Ls, solar longitude, is a measure of the time of year on Mars. Mars travels 360o around the Sun in 1 Mars year. The year begins at Ls 0o, the start of northern spring and southern autumn. Season: Northern Winter/Southern Summer

  5. Eight-year climatology of dust optical depth on Mars

    Science.gov (United States)

    Montabone, L.; Forget, F.; Millour, E.; Wilson, R. J.; Lewis, S. R.; Cantor, B.; Kass, D.; Kleinböhl, A.; Lemmon, M. T.; Smith, M. D.; Wolff, M. J.

    2015-05-01

    We have produced a multiannual climatology of airborne dust from martian year 24-31 using multiple datasets of retrieved or estimated column optical depths. The datasets are based on observations of the martian atmosphere from April 1999 to July 2013 made by different orbiting instruments: the Thermal Emission Spectrometer (TES) aboard Mars Global Surveyor, the Thermal Emission Imaging System (THEMIS) aboard Mars Odyssey, and the Mars Climate Sounder (MCS) aboard Mars Reconnaissance Orbiter (MRO). The procedure we have adopted consists of gridding the available retrievals of column dust optical depth (CDOD) from TES and THEMIS nadir observations, as well as the estimates of this quantity from MCS limb observations. Our gridding method calculates averages and uncertainties on a regularly spaced spatio-temporal grid, using an iterative procedure that is weighted in space, time, and retrieval quality. The lack of observations at certain times and locations introduces missing grid points in the maps, which therefore may result in irregularly gridded (i.e. incomplete) fields. In order to evaluate the strengths and weaknesses of the resulting gridded maps, we compare with independent observations of CDOD by PanCam cameras and Mini-TES spectrometers aboard the Mars Exploration Rovers "Spirit" and "Opportunity", by the Surface Stereo Imager aboard the Phoenix lander, and by the Compact Reconnaissance Imaging Spectrometer for Mars aboard MRO. We have statistically analyzed the irregularly gridded maps to provide an overview of the dust climatology on Mars over eight years, specifically in relation to its interseasonal and interannual variability, in addition to provide a basis for instrument intercomparison. Finally, we have produced regularly gridded maps of CDOD by spatially interpolating the irregularly gridded maps using a kriging method. These complete maps are used as dust scenarios in the Mars Climate Database (MCD) version 5, and are useful in many modeling

  6. Satellite-Based Sunshine Duration for Europe

    Directory of Open Access Journals (Sweden)

    Bodo Ahrens

    2013-06-01

    Full Text Available In this study, two different methods were applied to derive daily and monthly sunshine duration based on high-resolution satellite products provided by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT Satellite Application Facility on Climate Monitoring using data from Meteosat Second Generation (MSG SEVIRI (Spinning Enhanced Visible and Infrared Imager. The satellite products were either hourly cloud type or hourly surface incoming direct radiation. The satellite sunshine duration estimates were not found to be significantly different using the native 15-minute temporal resolution of SEVIRI. The satellite-based sunshine duration products give additional spatial information over the European continent compared with equivalent in situ-based products. An evaluation of the satellite sunshine duration by product intercomparison and against station measurements was carried out to determine their accuracy. The satellite data were found to be within ±1 h/day compared to high-quality Baseline Surface Radiation Network or surface synoptic observations (SYNOP station measurements. The satellite-based products differ more over the oceans than over land, mainly because of the treatment of fractional clouds in the cloud type-based sunshine duration product. This paper presents the methods used to derive the satellite sunshine duration products and the performance of the different retrievals. The main benefits and disadvantages compared to station-based products are also discussed.

  7. Sixth International Workshop on the Mars Atmosphere: Modelling and Observations

    Science.gov (United States)

    Forget, F.; Millour, M.

    2017-01-01

    The scope of this workshop is to bring together experts in observations and modelling of the present and past Mars climate systems and discuss the nature of the atmospheric circulation and the photochemistry (up to the thermosphere), the dust cycle, the water cycle (vapor, clouds and frost) and the carbon dioxide cycle (polar caps).

  8. Review and Development on the Studies of Chinese Meteorological Satellite and Satellite Meteorology

    Institute of Scientific and Technical Information of China (English)

    FANG Zongyi; XU Jianmin; ZHAO Fengsheng

    2006-01-01

    Meteorological satellite and satellite meteorology are the fastest developing new branches in the atmospheric sciences. Today the meteorological satellite has become a key element in the global atmospheric sounding system while the satellite meteorology is covering the main components of earth's system science.This article describes the major achievements that China has made in these fields in the past 30 years.The following contents are involved: (1) History and present status of China's meteorological satellites. It covers the development, launch, operation, technical parameters of China's polar and geostationary meteorological satellites. (2) Major achievements on remote sensing principle and method. It describes the retrieval of atmospheric temperature and humidity profiles, cloud character retrieval, aerosol character retrieval, precipitation retrieval as well as the generation of cloud wind. (3) Achievement on the studies of meteorological satellite data application. This part covers the applications of meteorological satellite data to weather analysis and forecast, numerical forecast, climate monitoring, and prediction of short-term climate change. Besides, the new results on data assimilation, climate monitoring, and forecast are also included.

  9. Guidelines for 2008 MARS exercise

    CERN Multimedia

    HR Department

    2008-01-01

    Full details of the Merit Appraisal and Recognition Scheme (MARS) are available via the HR Department’s homepage or directly on the Department’s MARS web page: https://cern.ch/hr-dept/ https://cern.ch/hr-eguide/mars/mars.asp You will find on these pages: MARS procedures including the MARS timetable for proposals and decisions; Regulations with links to the scheme’s statutory basis; Frequently Asked Questions; Useful documents with links to relevant documentation; e.g. mandate of the Senior Staff Advisory Committee (SSAC); Related links and contacts. HR Department Tel. 73566

  10. Mars' atmosphere: Earth's sister and statistical twin

    Science.gov (United States)

    Chen, Wilbur; Lovejoy, Shaun; Muller, Jan-Peter

    2016-04-01

    Satellite-based Martian re-analyses have allowed unprecedented comparisons between our atmosphere and that of our sister planet, underlining various similarities and differences in their respective dynamics. Yet by focusing on large scale structures and deterministic mechanisms they have improved our understanding of the dynamics only over fairly narrow ranges of (near) planetary scales. However, the Reynolds numbers of the flows on both planets are larger than 1011 and dissipation only occurs at centimetric (Mars) or millimetric scales (Earth) so that over most of their scale ranges, the dynamics are fully turbulent. In this presentation, we therefore examine the high level, statistical, turbulent laws for the temperature, horizontal wind and surface pressure, finding that Earth and Mars have virtually identical statistical exponents: their statistics are very similar over wide ranges. Therefore, it would seem that with the exception of certain aspects of the largest scales (such as the role of dust in atmospheric heating on Mars, or of water in its various phases on Earth), that the nonlinear dynamics are very similar. We argue that this is a prediction of the classical laws of turbulence when extended to planetary scales, and that it supports our use of turbulent laws on both planetary atmospheres.

  11. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-10-01

    Presented at the 40th Congress of the IAF, Oct. 7-13, 1989 in Torremolinos, Malaga-Spain. The paper describes the design and analysis of Radioisotope Thermoelectric Generators (RTGs) for powering the Mars Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space for the U.S. DOE in support of the JPL MRSR Project. The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It summarizes the baseline RTG's mass breakdown, and presents a detailed description of its thermal, thermoelectric, and electrical analysis. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments. It provides a basis for selecting the optimum strategy for meeting the Mars Rover design goals with minimal programmatic risk and cost. There is a duplicate copy and three copies in the file.

  12. The Mars Plasma Environment

    CERN Document Server

    Russell, C. T

    2007-01-01

    Mars sits very exposed to the solar wind and, because it is a small planet, has but a weak hold on its atmosphere. The solar wind therefore plays an important role in the evolution of the martian atmosphere. Over the last four decades a series of European missions, first from the Soviet Union and more recently from the European Space Agency, together with a single investigation from the U.S., the Mars Global Surveyor spacecraft, have added immeasurably to our understanding of the interplay between the solar wind and Mars atmosphere. Most recently the measurements of the plasma and fast neutral populations, conducted on the Mars Express spacecraft by the ASPERA-3 instrument have been acquired and analyzed. Their presentation to the public, most notably at the workshop "The Solar Wind Interaction and Atmosphere Evolution of Mars" held in Kiruna in early 2006, was the inspiration for this series of articles. However participation in the Kiruna conference was not a selection criterion for this volume. The papers ...

  13. Thermophysical Properties of Mars' North Polar Layered Deposits and Related Materials from Mars Odyssey THEMIS

    Science.gov (United States)

    Vasavada, A. R.; Richardson, M. I.; Byrne, S.; Ivanov, A. B.; Christensen, P. R.

    2003-01-01

    The presence of a thick sequence of horizontal layers of ice-rich material at Mars north pole, dissected by troughs and eroding at its margins, is undoubtedly telling us something about the evolution of Mars climate [1,2] we just don t know what yet. The North Polar Layered Deposits (NPLD) most likely formed as astronomically driven climate variations led to the deposition of conformable, areally extensive layers of ice and dust over the polar region. More recently, the balance seems to have fundamentally shifted to net erosion, as evidenced by the many troughs within the NPLD and the steep, arcuate scarps present near its margins, both of which expose layering. We defined a number of Regions of Interest ROI) for THEMIS to target as part of the Mars Odyssey Participating Scientist program. We use these THEMIS data in order to understand the morphology and color/thermal properties of the NPLD and related materials over relevant (i.e., m to km) spatial scales. We have assembled color mosaics of our ROIs in order to map the distribution of ices, the different layered units, dark material, and underlying basement. The color information from THEMIS is crucial for distinguishing these different units which are less distinct on Mars Orbiter Camera images. We wish to understand the nature of the marginal scarps and their relationship to the dark material. Our next, more ambitious goal is to derive the thermophysical properties of the different geologic materials using THEMIS and Mars Global Surveyor Thermal Emission Spectrometer TES) data.

  14. Could Cirrus Clouds Have Warmed Early Mars?

    CERN Document Server

    Ramirez, Ramses M

    2016-01-01

    The presence of the ancient valley networks on Mars indicates that the climate at 3.8 Ga was warm enough to allow substantial liquid water to flow on the martian surface for extended periods of time. However, the mechanism for producing this warming continues to be debated. One hypothesis is that Mars could have been kept warm by global cirrus cloud decks in a CO2-H2O atmosphere containing at least 0.25 bar of CO2 (Urata and Toon, 2013). Initial warming from some other process, e.g., impacts, would be required to make this model work. Those results were generated using the CAM 3-D global climate model. Here, we use a single-column radiative-convective climate model to further investigate the cirrus cloud warming hypothesis. Our calculations indicate that cirrus cloud decks could have produced global mean surface temperatures above freezing, but only if cirrus cloud cover approaches ~75 - 100% and if other cloud properties (e.g., height, optical depth, particle size) are chosen favorably. However, at more real...

  15. Could cirrus clouds have warmed early Mars?

    Science.gov (United States)

    Ramirez, Ramses M.; Kasting, James F.

    2017-01-01

    The presence of the ancient valley networks on Mars indicates that the climate at 3.8 Ga was warm enough to allow substantial liquid water to flow on the martian surface for extended periods of time. However, the mechanism for producing this warming continues to be debated. One hypothesis is that Mars could have been kept warm by global cirrus cloud decks in a CO2sbnd H2O atmosphere containing at least 0.25 bar of CO2 (Urata and Toon, 2013). Initial warming from some other process, e.g., impacts, would be required to make this model work. Those results were generated using the CAM 3-D global climate model. Here, we use a single-column radioactive-convective climate model to further investigate the cirrus cloud warming hypothesis. Our calculations indicate that cirrus cloud decks could have produced global mean surface temperatures above freezing, but only if cirrus cloud cover approaches ∼75 - 100% and if other cloud properties (e.g., height, optical depth, particle size) are chosen favorably. However, at more realistic cirrus cloud fractions, or if cloud parameters are not optimal, cirrus clouds do not provide the necessary warming, suggesting that other greenhouse mechanisms are needed.

  16. Chinese Satellites Serve Beijing Olympic Games

    Institute of Scientific and Technical Information of China (English)

    Ren Shufang

    2008-01-01

    @@ METEOROLOGICAL SATELLITES PROVIDING WEATHER SERVICES As the opening and closing ceremonies and many competition events such as athletics, football, cycling and sailing etc., were held in open air stadiums, field or on water, it was of great importance to provide exact weather forecasts and on-time climate information to prepare for disastrous weather so as to ensure the Olympic Games proceeded smoothly. For this purpose, China launched the meteorological satellite service project in 2002 to safeguard the 2008 Beijing Olympic Games.

  17. Movements of Satellite-Tagged Blainville’s Beaked Whales Off the Island of Hawaii

    Science.gov (United States)

    2009-01-01

    Orcinus orca (Andrews et al. 2008). In 2006, satellite tags were deployed on 3 Blainville’s beaked whales, and, in 2008, we were able to deploy...2002) Assessment of Argos location accuracy from satellite tags deployed on captive gray seals. Mar Mamm Sci 18: 156–166 Weilgart LS (2007) The impacts

  18. Mars Spark Source Prototype

    Science.gov (United States)

    Eichenberg, Dennis J.; Lindamood, Glenn R.; Weiland, Karen J.; VanderWal, Randall L.

    1999-01-01

    The Mars Spark Source Prototype (MSSP) hardware has been developed as part of a proof of concept system for the detection of trace metals such as lead, cadmium, and arsenic in Martian dusts and soils. A spark discharge produces plasma from a soil sample and detectors measure the optical emission from metals in the plasma that will allow their identification and quantification. Trace metal measurements are vital for the assessment of the potential toxicity of the Martian environment for human exploration. The current method of X-ray fluorescence can yield concentrations only of major species. Other instruments are incompatible with the volume, weight, and power constraints for a Mars mission. The instrument will be developed primarily for use in the Martian environment, but would be adaptable for terrestrial use in environmental monitoring. This paper describes the Mars Spark Source Prototype hardware, the results of the characterization tests, and future plans for hardware development.

  19. Magnetic storms on Mars

    DEFF Research Database (Denmark)

    Vennerstrøm, Susanne

    2011-01-01

    Based on data from the Mars Global Surveyor magnetometer we examine periods of significantly enhanced magnetic disturbances in the martian space environment. Using almost seven years of observations during the maximum and early declining phase of the previous solar cycle the occurrence pattern...... and typical time profile of such periods is investigated and compared to solar wind measurements at Earth. Typical durations of the events are 20–40h, and there is a tendency for large events to last longer, but a large spread in duration and intensity are found. The large and medium intensity events at Mars...... field disturbance at Mars is solar wind dynamic pressure variations associated with the eccentricity of the martian orbit around the Sun....

  20. Remanent magnetism at Mars

    Science.gov (United States)

    Curtis, S. A.; Ness, N. F.

    1988-01-01

    It is shown that a strong case can be made for an intrinsic magnetic field of dynamo origin for Mars earlier in its history. The typical equatorial magnetic field intensity would have been equal to about 0.01-0.1 gauss. The earlier dynamo activity is no longer extant, but a significant remanent magnetic field may exist. A highly non-dipole magnetic field could result from the remanent magnetization of the surface. Remanent magnetization may thus play an important role in the Mars solar wind interactions, in contrast to Venus with its surface temperatures above the Curie point. The anomalous characteristics of Mars'solar wind interaction compared to that of Venus may be explicable on this basis.

  1. VR for Mars Pathfinder

    Science.gov (United States)

    Blackmon, Theodore

    1998-01-01

    Virtual reality (VR) technology has played an integral role for Mars Pathfinder mission, operations Using an automated machine vision algorithm, the 3d topography of the Martian surface was rapidly recovered fro -a the stereo images captured. by the Tender camera to produce photo-realistic 3d models, An advanced, interface was developed for visualization and interaction with. the virtual environment of the Pathfinder landing site for mission scientists at the Space Flight Operations Facility of the Jet Propulsion Laboratory. The VR aspect of the display allowed mission scientists to navigate on Mars in Bud while remaining here on Earth, thus improving their spatial awareness of the rock field that surrounds the lenders Measurements of positions, distances and angles could be easily extracted from the topographic models, providing valuable information for science analysis and mission. planning. Moreover, the VR map of Mars has also been used to assist with the archiving and planning of activities for the Sojourner rover.

  2. Spiders from Mars?

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-426, 19 July 2003No, this is not a picture of a giant, martian spider web. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a plethora of polygonal features on the floor of a northern hemisphere impact crater near 65.6oN, 327.7oW. The picture was acquired during spring, after the seasonal carbon dioxide frost cap had largely migrated through the region. At the time the picture was taken, remnants of seasonal frost remained on the crater rim and on the edges of the troughs that bound each of the polygons. Frost often provides a helpful hint as to where polygons and patterned ground occur. The polygons, if they were on Earth, would indicate the presence of freeze-thaw cycles in ground ice. Although uncertain, the same might be true of Mars. Sunlight illuminates the scene from the lower left.

  3. For a Cup of Water on Mars: Gusev Crater

    Science.gov (United States)

    Martel, L. M. V.

    1998-09-01

    Though liquid water is not stable on the surface of Mars today, there are hints in the Martian landscape that water once flowed there, eroding valleys and depositing sediments. Understanding where water is, or was, on Mars is a crucial step in looking for life on this smaller, cooler neighbor of Earth. Satellite images, beginning in the early 1970s with Mariner 9 up to the current Mars Global Surveyor, have given us increasingly detailed looks at the surface of Mars, including those intriguing channels that resemble dry river valleys. Warmer temperatures and a higher surface pressure once made it possible for liquid water to exist on the surface of Mars. When the water existed and where it went are just two of the questions being studied today. A larger question has to do with Martian life. If the wetter, early environment on Mars supported life, then where are the most appropriate places to look for evidence of life? The answer seems to be channels and ancient lake beds. Nathalie Cabrol and colleagues at NASA Ames Research Center, the Vernadksy Institute in Moscow, and Arizona State University recently published their study of a valley and impact crater on Mars which together had a prolonged history of water-related activity. The researchers established a sequence of events for the Ma'adim Vallis/Gusev crater area that included flowing water, ponding, and sedimentation over a period of a couple of billion years. This history makes Gusev crater a prominent depositional site and a key location for future biological explorations on Mars.

  4. The AMADEE-15 Mars simulation

    Science.gov (United States)

    Groemer, Gernot; Losiak, Anna; Soucek, Alexander; Plank, Clemens; Zanardini, Laura; Sejkora, Nina; Sams, Sebastian

    2016-12-01

    We report on the AMADEE-15 mission, a 12-day Mars analog field test at the Kaunertal Glacier in Austria. Eleven experiments were conducted by a field crew at the test site under simulated martian surface exploration conditions and coordinated by a Mission Support Center in Innsbruck, Austria. The experiments' research fields encompassed geology, human factors, astrobiology, robotics, tele-science, exploration, and operations research. A Remote Science Support team analyzed field data in near real time, providing planning input for a flight control team to manage a complex system of field assets in a realistic work flow, including: two advanced space suit simulators; and four robotic and aerial vehicles. Field operations were supported by a dedicated flight planning group, an external control center tele-operating the PULI-rover, and a medical team. A 10-min satellite communication delay and other limitations pertinent to human planetary surface activities were introduced. This paper provides an overview of the geological context and environmental conditions of the test site and the mission architecture, with a focus on the mission's communication infrastructure. We report on the operational workflows and the experiments conducted, as well as a novel approach of measuring mission success through the introduction of general analog mission transferrable performance indicators.

  5. The Effect of CO2 Ice Cap Sublimation on Mars Atmosphere

    Science.gov (United States)

    Batterson, Courtney

    2016-01-01

    Sublimation of the polar CO2 ice caps on Mars is an ongoing phenomenon that may be contributing to secular climate change on Mars. The transfer of CO2 between the surface and atmosphere via sublimation and deposition may alter atmospheric mass such that net atmospheric mass is increasing despite seasonal variations in CO2 transfer. My study builds on previous studies by Kahre and Haberle that analyze and compare data from the Phoenix and Viking Landers 1 and 2 to determine whether secular climate change is happening on Mars. In this project, I use two years worth of temperature, pressure, and elevation data from the MSL Curiosity rover to create a program that allows for successful comparison of Curiosity pressure data to Viking Lander pressure data so a conclusion can be drawn regarding whether CO2 ice cap sublimation is causing a net increase in atmospheric mass and is thus contributing to secular climate change on Mars.

  6. Mars Aqueous Processing System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Aqueous Processing System (MAPS) is a novel technology for recovering oxygen, iron, and other constituents from lunar and Mars soils. The closed-loop...

  7. The Mars Pathfinder Mission

    Science.gov (United States)

    Golombek, M. P.

    1996-09-01

    The Mars Pathfinder mission is a Discovery class mission that will place a small lander and rover on the surface of Mars on July 4, 1997. The Pathfinder flight system is a single small lander, packaged within an aeroshell and back cover with a back-pack-style cruise stage. The vehicle will be launched, fly independently to Mars, and enter the atmosphere directly on approach behind the aeroshell. The vehicle is slowed by a parachute and 3 small solid rockets before landing on inflated airbags. Petals of a small tetrahedron shaped lander open up, to right the vehicle. The lander is solar powered with batteries and will operate on the surface for up to a year, downlinking data on a high-gain antenna. Pathfinder will be the first mission to use a rover, with 3 imagers and an alpha proton X-ray spectrometer, to characterize the rocks and soils in a landing area over hundreds of square meters on Mars, which will provide a calibration point or "ground truth" for orbital remote sensing observations. The rover (includes a series of technology experiments), the instruments (including a stereo multispectral surface imager on a pop up mast and an atmospheric structure instrument-surface meteorology package) and the telemetry system will allow investigations of: the surface morphology and geology at meter scale, the petrology and geochemistry of rocks and soils, the magnetic properties of dust, soil mechanics and properties, a variety of atmospheric investigations and the rotational and orbital dynamics of Mars. Landing downstream from the mouth of a giant catastrophic outflow channel, Ares Vallis, offers the potential of identifying and analyzing a wide variety of crustal materials, from the ancient heavily cratered terrain, intermediate-aged ridged plains and reworked channel deposits, thus allowing first-order scientific investigations of the early differentiation and evolution of the crust, the development of weathering products and early environments and conditions on Mars.

  8. Nuclear Planetology: Especially Concerning the Moon and Mars

    Science.gov (United States)

    Kim, Kyeong Ja; Hasebe, Nobuyuki

    2012-10-01

    To approach basic scientific questions on the origin and evolution of planetary bodies such as planets, their satellites and asteroids, one needs data on their chemical composition. The measurements of gamma-rays, X-rays and neutrons emitted from their surface materials provide information on abundances of major elements and naturally radioactive gamma-ray emitters. Neutron spectroscopy can provide sensitive maps of hydrogen- and carbon-containing compounds, even if buried, and can uniquely identify layers of carbon-dioxide frost. Nuclear spectroscopy, as a means of compositional analysis, has been applied via orbital and lander spacecraft to extraterrestrial planetary bodies: the Moon, Venus, Mars, Mercury and asteroids. The knowledge of their chemical abundances, especially concerning the Moon and Mars, has greatly increased in recent years. This paper describes the principle of nuclear spectroscopy, nuclear planetary instruments carried on planetary missions so far, and the nature of observational results and findings of the Moon and Mars, recently obtained by nuclear spectroscopy.

  9. Flying To Mars

    Institute of Scientific and Technical Information of China (English)

    周铭杨

    2015-01-01

    <正>Do you know"Mars migration programme"by SpaceX?It’s an immigrant plan to a planet—Mars,Sounds incredible,isn’t it?After two-round tests,Li Dapeng,graduating from Handan NO.1 high school in 2001,was selected.There entered four Chinese in final test.To be more precise,Li is the only one who comes from the mainland of China.Last weekend,Li came to our school for a speech.Driven by

  10. EquiMar

    DEFF Research Database (Denmark)

    Johnstone, C. M.; McCombes, T.; Bahaj, A. S.

    2011-01-01

    / financiers etc when attempting to quantify the performance of a device since it makes it very difficult to reference and benchmark the performance of a marine energy converter. The EC Framework Programme VII EquiMar project has set out to develop a suite of Best Practices to be adopted when undertaking...... the performance evaluation of such systems in order to address this deficiency. This paper reports the development of a set of ‘Best Practices’ within the ECFPVII EquiMar project to be adopted for the performance quantification of wave and tidal energy converters as they evolve from an engineering concept...

  11. Mars Obliquity Cycle Illustration

    Science.gov (United States)

    2008-01-01

    The tilt of Mars' spin axis (obliquity) varies cyclically over hundreds of thousands of years, and affects the sunlight falling on the poles. Because the landing site of NASA's Phoenix Mars Lander is so near the north pole, higher sun and warmer temperatures during high obliquity lead to warmer, more humid surface environments, and perhaps thicker, more liquid-like films of water in soil. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  12. Vulkanisme en water op Mars?

    NARCIS (Netherlands)

    Van Loef, J.; Schmets, A.J.M.

    2005-01-01

    In januari 2004 werd Mars bezocht door de tweeling robotverkenners Spirit en Opportunity. Zij werden erop uitgestuurd om eindelijk het definitieve antwoord te geven op de vraag of er leven op Mars is geweest. Alles wijst er inmiddels op dat er op Mars ooit vloeibaar water stroomde. Of daarmee een

  13. Vulkanisme en water op Mars?

    NARCIS (Netherlands)

    Van Loef, J.; Schmets, A.J.M.

    2005-01-01

    In januari 2004 werd Mars bezocht door de tweeling robotverkenners Spirit en Opportunity. Zij werden erop uitgestuurd om eindelijk het definitieve antwoord te geven op de vraag of er leven op Mars is geweest. Alles wijst er inmiddels op dat er op Mars ooit vloeibaar water stroomde. Of daarmee een be

  14. Vulkanisme en water op Mars?

    NARCIS (Netherlands)

    Van Loef, J.; Schmets, A.J.M.

    2005-01-01

    In januari 2004 werd Mars bezocht door de tweeling robotverkenners Spirit en Opportunity. Zij werden erop uitgestuurd om eindelijk het definitieve antwoord te geven op de vraag of er leven op Mars is geweest. Alles wijst er inmiddels op dat er op Mars ooit vloeibaar water stroomde. Of daarmee een be

  15. Climate Literacy Ambassadors

    Science.gov (United States)

    Ackerman, S. A.; Mooney, M. E.

    2011-12-01

    The Climate Literacy Ambassadors program is a collaborative effort to advance climate literacy led by the Cooperative Institute of Meteorological Satellite Studies (CIMSS) at the University of Wisconsin-Madison. With support from NASA, CIMSS is coordinating a three-tiered program to train G6-12 teachers to be Ambassadors of Climate Literacy in their schools and communities. The complete training involves participation at a teacher workshop combined with web-based professional development content around Global and Regional Climate Change. The on-line course utilizes e-learning technology to clarify graphs and concepts from the 2007 Intergovernmental Panel on Climate Change Summary for Policy Makers with content intricately linked to the Climate Literacy: The Essential Principles of Climate Science. Educators who take the course for credit can develop lesson plans or opt for a project of their choosing. This session will showcase select lesson plans and projects, ranging from a district-wide action plan that engaged dozens of teachers to Ambassadors volunteering at the Aldo Leopold Climate Change Nature Center to a teacher who tested a GLOBE Student Climate Research Campaign (SCRC) learning project with plans to participate in the SCRC program. Along with sharing successes from the CIMSS Climate Literacy Ambassadors project, we will share lessons learned related to the challenges of sustaining on-line virtual educator communities.

  16. An ice age recorded in the polar deposits of Mars.

    Science.gov (United States)

    Smith, Isaac B; Putzig, Nathaniel E; Holt, John W; Phillips, Roger J

    2016-05-27

    Layered ice deposits at the poles of Mars record a detailed history of accumulation and erosion related to climate processes. Radar investigations measure these layers and provide evidence for climate changes such as ice advance and retreat. We present a detailed analysis of observational data showing that ~87,000 cubic kilometers of ice have accumulated at the poles since the end of the last ice age ~370,000 years ago; this volume is equivalent to a global layer of ~60 centimeters. The majority of the material accumulated at the north pole. These results provide both a means to understand the accumulation history of the polar deposits as related to orbital Milankovitch cycles and constraints for better determination of Mars' past and future climates.

  17. Ice-related landforms in Hydrae chasma, Mars

    Science.gov (United States)

    Baioni, Davide; Tramontana, Mario

    2016-04-01

    Hydrae Chasma is one of the smaller chasma of Valles Marineris. It is a circular depression approximately 50 kilometers across and 4 kilometers deep, located to the north of Coprates Chasma and south of Juventae Chasma A morphological survey of Hydrae Chasma through an analysis of the available Mars images was performed. The features of the landforms were investigated through an integrated analysis of Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) and Context Camera (CTX) data. Landforms interpreted as due to ice-related processes, resembling similarly ice-related landforms found both in the cold-climate non glacial regions of the Earth, and putatively in other areas of Mars, was observed. These landforms are attributed to the presence of ground ice and/or ice-melting processes reflect significant climatic changes and different climatic conditions than those existing now. Moreover, they appear to display young erosional age, suggesting that are probably of Amazonian age.

  18. The interannual variability of polar cap recessions as a measure of Martian climate and weather: Using Earth-based data to augment the time line for the Mars observer mapping mission

    Science.gov (United States)

    Martin, L. J.; James, P. B.

    1992-01-01

    The recessions of the polar ice caps are the most visible and most studied indication of seasonal change on Mars. Circumstantial evidence links these recessions to the seasonal cycles of CO2, water, and dust. The possible advent of a planet encircling storm during the Mars Observer (MO) mission will provide a detailed correlation with a cap recession for that one Martian year. That cap recession will then be compared with other storm and nonstorm years. MO data will also provide a stronger link between cap recessions and the water and CO2 cycles. Cap recession variability might also be used to determine the variability of these cycles. After nearly a century of valiant attempts at measuring polar cap recessions, including Mariner 9 and Viking data, MO will provide the first comprehensive dataset. In contrast to MO, the older data are much less detailed and precise and could be forgotten, except that it will still be the only information on interannual variability. By obtaining simultaneous Earth-based observations (including those from Hubble) during the MO mission, direct comparisons can be made between the datasets.

  19. Electrochemical approaches for chemical and biological analysis on Mars

    Science.gov (United States)

    Kounaves, Samuel P.

    2003-01-01

    Obtaining in situ chemical data from planetary bodies such as Mars or Europa can present significant challenges. The one analytical technique that has many of the requisite characteristics to meet such a challenge is electroanalysis. Described here are three electroanalytical devices designed for in situ geochemical and biological analysis on Mars. The Mars Environmental Compatibility Assessment (MECA) was built and flight qualified for the now cancelled NASA Mars 2001 Lander. Part of MECA consisted of four "cells" containing arrays of electrochemical based sensors for measuring the ionic species in soil samples. A next-generation MECA, the Robotic Chemical Analysis Laboratory (RCAL), uses a carousel-type system to allow for greater customization of analytical procedures. A second instrument, proposed as part of the 2007 CryoScout mission, consists of a flow-through inorganic chemical analyzer (MICA). CryoScout is a torpedo-like device designed for subsurface investigation of the stratigraphic climate record embedded in Mars' north polar cap. As the CryoScout melts its way through the ice cap, MICA will collect and analyze the meltwater for a variety of inorganics and chemical parameters. By analyzing the chemistry locked in the layers of dust, salt, and ice, geologists will be able to determine the recent history of climate, water, and atmosphere on Mars and link it to the past. Finally, electroanalysis shows its abilities in the detection of possible microorganism on Mars or elsewhere in the solar system. To identify an unknown microorganism, one that may not even use Earth-type biochemistry, requires a detection scheme which makes minimal assumptions and looks for the most general features. Recent work has demonstrated that the use of an array of electrochemical sensors which monitors the changes in a solution via electrical conductivity, pH, and ion selective electrodes, can be used to detect minute chemical perturbations caused by the growth of bacteria and

  20. Marli: Mars Lidar for Global Wind Profiles and Aerosol Profiles from Orbit

    Science.gov (United States)

    Abshire, J. B.; Guzewich, S. D.; Smith, M. D.; Riris, H.; Sun, X.; Gentry, B. M.; Yu, A.; Allan, G. R.

    2016-01-01

    The Mars Exploration Analysis Group's Next Orbiter Science Analysis Group (NEXSAG) has recently identified atmospheric wind measurements as one of 5 top compelling science objectives for a future Mars orbiter. To date, only isolated lander observations of martian winds exist. Winds are the key variable to understand atmospheric transport and answer fundamental questions about the three primary cycles of the martian climate: CO2, H2O, and dust. However, the direct lack of observations and imprecise and indirect inferences from temperature observations leave many basic questions about the atmospheric circulation unanswered. In addition to addressing high priority science questions, direct wind observations from orbit would help validate 3D general circulation models (GCMs) while also providing key input to atmospheric reanalyses. The dust and CO2 cycles on Mars are partially coupled and their influences on the atmospheric circulation modify the global wind field. Dust absorbs solar infrared radiation and its variable spatial distribution forces changes in the atmospheric temperature and wind fields. Thus it is important to simultaneously measure the height-resolved wind and dust profiles. MARLI provides a unique capability to observe these variables continuously, day and night, from orbit.

  1. Ancient aliens on mars

    CERN Document Server

    Bara, Mike

    2013-01-01

    Best-selling author and Secret Space Program researcher Bara brings us this lavishly illustrated volume on alien structures on Mars. Was there once a vast, technologically advanced civilization on Mars, and did it leave evidence of its existence behind for humans to find eons later? Did these advanced extraterrestrial visitors vanish in a solar system wide cataclysm of their own making, only to make their way to Earth and start anew? Was Mars once as lush and green as the Earth, and teeming with life? Did Mars once orbit a missing member of the solar system, a "Super Earth” that vanished in a disaster that devastated life on Earth and Venus and left us only the asteroid belt as evidence of its once grand existence? Did the survivors of this catastrophe leave monuments and temples behind, arranged in a mathematical precision designed to teach us the Secret of a new physics that could lift us back to the stars? Does the planet have an automated defense shield that swallows up robotic probes if they wander int...

  2. Mission from Mars

    DEFF Research Database (Denmark)

    Dindler, Christian; Eriksson, Eva; Iversen, Ole Sejer

    2005-01-01

    In this paper a particular design method is propagated as a supplement to existing descriptive approaches to current practice studies especially suitable for gathering requirements for the design of children's technology. The Mission from Mars method was applied during the design of an electronic...

  3. Carbon sequestration on Mars

    OpenAIRE

    Edwards, Christopher S.; Ehlmann, Bethany L.

    2015-01-01

    On Earth, carbon sequestration in geologic units plays an important role in the carbon cycle, scrubbing CO_2 from the atmosphere for long-term storage. While carbonate is identified in low abundances within the dust and soils of Mars, at

  4. Mission from Mars:

    DEFF Research Database (Denmark)

    Dindler, Christian; Eriksson, Eva; Iversen, Ole Sejer

    2005-01-01

    In this paper a particular design method is propagated as a supplement to existing descriptive approaches to current practice studies especially suitable for gathering requirements for the design of children's technology. The Mission from Mars method was applied during the design of an electronic...

  5. The Phoenix Mars Mission

    Science.gov (United States)

    Tamppari, Leslie K.; Smith, Peter H.

    2008-01-01

    This slide presentation details the Phoenix Mission which was designed to enhance our understanding of water and the potential for habitability on the north polar regions of Mars. The slides show the instruments and the robotics designed to scrape Martian surface material, and analyze it in hopes of identifying water in the form of ice, and other chemicals.

  6. Geostationary Satellite (GOES) Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Visible and Infrared satellite imagery taken from radiometer instruments on SMS (ATS) and GOES satellites in geostationary orbit. These satellites produced...

  7. Distributed Anomaly Detection Using Satellite Data From Multiple Modalities

    Data.gov (United States)

    National Aeronautics and Space Administration — There has been a tremendous increase in the volume of Earth Science data over the last decade from modern satellites, in-situ sensors and different climate models....

  8. The Small Mars System

    Science.gov (United States)

    Fantino, E.; Grassi, M.; Pasolini, P.; Causa, F.; Molfese, C.; Aurigemma, R.; Cimminiello, N.; de la Torre, D.; Dell'Aversana, P.; Esposito, F.; Gramiccia, L.; Paudice, F.; Punzo, F.; Roma, I.; Savino, R.; Zuppardi, G.

    2017-08-01

    The Small Mars System is a proposed mission to Mars. Funded by the European Space Agency, the project has successfully completed Phase 0. The contractor is ALI S.c.a.r.l., and the study team includes the University of Naples ;Federico II;, the Astronomical Observatory of Capodimonte and the Space Studies Institute of Catalonia. The objectives of the mission are both technological and scientific, and will be achieved by delivering a small Mars lander carrying a dust particle analyser and an aerial drone. The former shall perform in situ measurements of the size distribution and abundance of dust particles suspended in the Martian atmosphere, whereas the latter shall demonstrate low-altitude flight in the rarefied planetary environment. The mission-enabling technology is an innovative umbrella-like heat shield, known as IRENE, developed and patented by ALI. The mission is also a technological demonstration of the shield in the upper atmosphere of Mars. The core characteristics of SMS are the low cost (120 M€) and the small size (320 kg of wet mass at launch, 110 kg at landing), features which stand out with respect to previous Mars landers. To comply with them is extremely challenging at all levels, and sets strict requirements on the choice of the materials, the sizing of payloads and subsystems, their arrangement inside the spacecraft and the launcher's selection. In this contribution, the mission and system concept and design are illustrated and discussed. Special emphasis is given to the innovative features and to the challenges faced in the development of the work.

  9. [MaRS Project

    Science.gov (United States)

    Aruljothi, Arunvenkatesh

    2016-01-01

    The Space Exploration Division of the Safety and Mission Assurances Directorate is responsible for reducing the risk to Human Space Flight Programs by providing system safety, reliability, and risk analysis. The Risk & Reliability Analysis branch plays a part in this by utilizing Probabilistic Risk Assessment (PRA) and Reliability and Maintainability (R&M) tools to identify possible types of failure and effective solutions. A continuous effort of this branch is MaRS, or Mass and Reliability System, a tool that was the focus of this internship. Future long duration space missions will have to find a balance between the mass and reliability of their spare parts. They will be unable take spares of everything and will have to determine what is most likely to require maintenance and spares. Currently there is no database that combines mass and reliability data of low level space-grade components. MaRS aims to be the first database to do this. The data in MaRS will be based on the hardware flown on the International Space Stations (ISS). The components on the ISS have a long history and are well documented, making them the perfect source. Currently, MaRS is a functioning excel workbook database; the backend is complete and only requires optimization. MaRS has been populated with all the assemblies and their components that are used on the ISS; the failures of these components are updated regularly. This project was a continuation on the efforts of previous intern groups. Once complete, R&M engineers working on future space flight missions will be able to quickly access failure and mass data on assemblies and components, allowing them to make important decisions and tradeoffs.

  10. Mars Surface Environmental Issues

    Science.gov (United States)

    Charles, John

    2002-01-01

    Planetary exploration by astronauts will require extended periods of habitation on a planet's surface, under the influence of environmental factors that are different from those of Earth and the spacecraft that delivered the crew to the planet. Human exploration of Mars, a possible near-term planetary objective, can be considered a challenging scenario. Mission scenarios currently under consideration call for surface habitation periods of from 1 to 18 months on even the earliest expeditions. Methods: Environmental issues associated with Mars exploration have been investigated by NASA and the National Space Biomedical Research Institute (NSBRI) as part of the Bioastronautics Critical Path Roadmap Project (see http ://criticalpath.jsc.nasa.gov). Results: Arrival on Mars will immediately expose the crew to gravity only 38% of that at Earth's surface in possibly the first prolonged exposure to gravity other than the 1G of Earth's surface and the zero G of weightless space flight, with yet unknown effects on crew physiology. The radiation at Mars' surface is not well documented, although the planet's bulk and even its thin atmosphere may moderate the influx of galactic cosmic radiation and energetic protons from solar flares. Secondary radiation from activated components of the soil must also be considered. Ultrafine and larger respirable and nonrespirable particles in Martian dust introduced into the habitat after surface excursions may induce pulmonary inflammation exacerbated by the additive reactive and oxidizing nature of the dust. Stringent decontamination cannot eliminate mechanical and corrosive effects of the dust on pressure suits and exposed machinery. The biohazard potential of putative indigenous Martian microorganisms may be assessed by comparison with analog environments on Earth. Even in their absence, human microorganisms, if not properly controlled, can be a threat to the crew's health. Conclusions: Mars' surface offers a substantial challenge to the

  11. Neptune's small satellites

    Science.gov (United States)

    Thomas, P.

    1992-04-01

    The small satellites of Neptune and other planets discovered during the Voyager 2 mission are discussed in terms of their composition and relationship to the planetary systems. The satellite Proteus is described in terms of its orbit, five other satellites are described, and they are compared to ther small satellites and systems. Neptune's satellites are hypothesized to be related to the ring system, and the satellite Galatea is related to the confinement of the rings.

  12. Widespread Excess Ice in Arcadia Planitia, Mars

    CERN Document Server

    Bramson, Ali M; Putzig, Nathaniel E; Sutton, Sarah; Plaut, Jeffrey J; Brothers, T Charles; Holt, John W

    2015-01-01

    The distribution of subsurface water ice on Mars is a key constraint on past climate, while the volumetric concentration of buried ice (pore-filling versus excess) provides information about the process that led to its deposition. We investigate the subsurface of Arcadia Planitia by measuring the depth of terraces in simple impact craters and mapping a widespread subsurface reflection in radar sounding data. Assuming that the contrast in material strengths responsible for the terracing is the same dielectric interface that causes the radar reflection, we can combine these data to estimate the dielectric constant of the overlying material. We compare these results to a three-component dielectric mixing model to constrain composition. Our results indicate a widespread, decameters-thick layer that is excess water ice ~10^4 km^3 in volume. The accumulation and long-term preservation of this ice is a challenge for current Martian climate models.

  13. Exploring the Cloud Icy Early Mars Hypothesis Through Geochemistry and Mineralogy

    Science.gov (United States)

    Niles, P. B.; Michalski, J. R.

    2015-01-01

    While ancient fluvial channels have long been considered strong evidence for early surface water on Mars, many aspects of the fluvial morphology and occurrence suggest that they formed in relatively water limited conditions (com-pared to Earth) and that climatic excursions allowing for surface water might have been short-lived. Updated results mapping valley networks at higher resolution have changed this paradigm, showing that channels are much more abundant and wide-spread, and of higher order than was previously recognized, suggesting that Mars had a dense enough atmosphere and warm enough climate to allow channel formation up to 3.6-3.8 Ga. This revised view of the ancient martian climate might be broadly consistent with a climate history of Mars devised from infrared remote sensing of surface minerals, suggesting that widespread clay minerals formed in the Noachian, giving way to a sulfur-dominated surface weathering system by approx. 3.7 Ga.

  14. An Undergraduate Endeavor: Assembling a Live Planetarium Show About Mars

    Science.gov (United States)

    McGraw, Allison M.

    2016-10-01

    Viewing the mysterious red planet Mars goes back thousands of years with just the human eye but in more recent years the growth of telescopes, satellites and lander missions unveil unrivaled detail of the Martian surface that tells a story worth listening to. This planetarium show will go through the observations starting with the ancients to current understandings of the Martian surface, atmosphere and inner-workings through past and current Mars missions. Visual animations of its planetary motions, display of high resolution images from the Hi-RISE (High Resolution Imaging Science Experiment) and CTX (Context Camera) data imagery aboard the MRO (Mars Reconnaissance Orbiter) as well as other datasets will be used to display the terrain detail and imagery of the planet Mars with a digital projection system. Local planetary scientists and Mars specialists from the Lunar and Planetary Lab at the University of Arizona (Tucson, AZ) will be interviewed and used in the show to highlight current technology and understandings of the red planet. This is an undergraduate project that is looking for collaborations and insight in order gain structure in script writing that will teach about this planetary body to all ages in the format of a live planetarium show.

  15. Climate Change: A Multidisciplinary Approach, Second Edition

    Science.gov (United States)

    Kirk-Davidoff, Daniel

    2008-07-01

    William Burroughs, who died in November 2007, was a wonderfully clear and evocative writer. Chapter 3 of his last work, Climate Change: A Multidisciplinary Approach, begins with the loveliest four-paragraph description of the general circulation of the Earth's atmosphere I have ever encountered. His writing also shines in his descriptions of the climate record of the past few thousand years, and in his introduction to the measurement of climate change. Unfortunately, the book is marred by inconsistencies in its treatment of climate dynamics, as well as by a number of idiosyncratic choices of emphasis that detract from the book's quality as a general introduction to the science of climate change.

  16. MAVEN Observations of Atmospheric Loss at Mars

    Science.gov (United States)

    Curry, Shannon; Luhmann, Janet; Jakosky, Bruce M.; Brain, David; LeBlanc, Francis; Modolo, Ronan; Halekas, Jasper S.; Schneider, Nicholas M.; Deighan, Justin; McFadden, James; Espley, Jared R.; Mitchell, David L.; Connerney, J. E. P.; Dong, Yaxue; Dong, Chuanfei; Ma, Yingjuan; Cohen, Ofer; Fränz, Markus; Holmström, Mats; Ramstad, Robin; Hara, Takuya; Lillis, Robert J.

    2016-06-01

    The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission has been making observations of the Martian upper atmosphere and its escape to space since November 2014. The subject of atmospheric loss at terrestrial planets is a subject of intense interest not only because of the implications for past and present water reservoirs, but also for its impacts on the habitability of a planet. Atmospheric escape may have been especially effective at Mars, relative to Earth or Venus, due to its smaller size as well as the lack of a global dynamo magnetic field. Not only is the atmosphere less gravitationally bound, but also the lack of global magnetic field allows the impinging solar wind to interact directly with the Martian atmosphere. When the upper atmosphere is exposed to the solar wind, planetary neutrals can be ionized and 'picked up' by the solar wind and swept away.Both neutral and ion escape have played significant roles the long term climate change of Mars, and the MAVEN mission was designed to directly measure both escaping planetary neutrals and ions with high energy, mass, and time resolution. We will present 1.5 years of observations of atmospheric loss at Mars over a variety of solar and solar wind conditions, including extreme space weather events. We will report the average ion escape rate and the spatial distribution of escaping ions as measured by MAVEN and place them in context both with previous measurements of ion loss by other spacecraft (e.g. Phobos 2 and Mars Express) and with estimates of neutral escape rates by MAVEN. We will then report on the measured variability in ion escape rates with different drivers (e.g. solar EUV, solar wind pressure, etc.) and the implications for the total ion escape from Mars over time. Additionally, we will also discuss the implications for atmospheric escape at exoplanets, particularly weakly magnetized planetary bodies orbiting M-dwarfs, and the dominant escape mechanisms that may drive atmospheric erosion in other

  17. Icebergs on early Mars

    Science.gov (United States)

    Uceda, E.; Fairen, A.; Woodworth-Lynas, C.; Palmero Rodriguez, A.

    2015-12-01

    The smooth topography of the Martian northern lowlands has been classically equated to an ancient ocean basin. The High-Resolution Imaging Science Experiment (HiRISE) onboard the Mars Reconnaissance Orbiter (MRO) is providing unprecedented images of the Martian surface at scales of 25 to 32 cm per pixel. The analysis of this high-resolution imaging reveals the presence of three differentiated geomorphologies throughout the northern lowlands of Mars and the Hellas basin, which are informative of the presence of icebergs floating in ancient oceans and/or seas. These morphologies are: (i) scattered scour marks, including curvilinear furrows several km long and some meters deep; (ii) boulders ranging in size from 0.5 m to ~2 m in diameter, distributed forming clusters with sizes from several hundred meters to 1-2 km; and (iii) flat-topped and conical circular fractured mounds. The association of plough marks, clusters of boulders and mounds on the northern plains of Mars can be related to the dual processes of ice keel scouring and ice rafting of both glacial and non-glacial detritus by a floating ice canopy and icebergs. These processes are well documented on Earth and result in distinct morphologies on the ocean floor, which are analogous to features observed in the Martian basins. Importantly, the features are located in elevated areas of the northern plains and Hellas, near the dichotomy boundary and on local topographic highs. Such distribution is expected, as these relatively shoal areas are where the iceberg-related features should occur on Mars: these areas had shallow water depths, less than the iceberg's keel depth, and therefore keels reached through the full depth of the water column to impinge on the sediments below. The presence of icebergs floating in cold oceans early in Mars' history imply the occurrence of continental glaciers forming in the highlands and streaming northward towards the lowlands, and towards the Hellas and Argyre Basins. Glacier

  18. Mars EXpress: status and recent findings

    Science.gov (United States)

    Titov, Dmitri; Bibring, Jean-Pierre; Cardesin, Alejandro; Duxbury, Tom; Forget, Francois; Giuranna, Marco; Holmstroem, Mats; Jaumann, Ralf; Martin, Patrick; Montmessin, Franck; Orosei, Roberto; Paetzold, Martin; Plaut, Jeff; MEX SGS Team

    2016-04-01

    Mars Express has entered its second decade in orbit in excellent health. The mission extension in 2015-2016 aims at augmenting of the surface coverage by imaging and spectral imaging instruments, continuing monitoring of the climate parameters and their variability, study of the upper atmosphere and its interaction with the solar wind in collaboration with NASA's MAVEN mission. Characterization of geological processes and landforms on Mars on a local-to-regional scale by HRSC camera constrained the martian geological activity in space and time and suggested its episodicity. Six years of spectro-imaging observations by OMEGA allowed correction of the surface albedo for presence of the atmospheric dust and revealed changes associated with the dust storm seasons. Imaging and spectral imaging of the surface shed light on past and present aqueous activity and contributed to the selection of the Mars-2018 landing sites. More than a decade long record of climatological parameters such as temperature, dust loading, water vapor, and ozone abundance was established by SPICAM and PFS spectrometers. Observed variations of HDO/H2O ratio above the subliming North polar cap suggested seasonal fractionation. The distribution of aurora was found to be related to the crustal magnetic field. ASPERA observations of ion escape covering a complete solar cycle revealed important dependences of the atmospheric erosion rate on parameters of the solar wind and EUV flux. Structure of the ionosphere sounded by MARSIS radar and MaRS radio science experiment was found to be significantly affected by the solar activity, crustal magnetic field as well as by influx of meteorite and cometary dust. The new atlas of Phobos based on the HRSC imaging was issued. The talk will give the mission status and review recent science highlights.

  19. Gone with the Wind ON_Mars (GOWON): A Wind-Driven Networked System of Mobile Sensors on Mars

    CERN Document Server

    Davoodi, Faranak; Murphy, Neil; Mischna, Michael; Nesnas, Issa; Nikzad, Shouleh

    2012-01-01

    We propose a revolutionary way of studying the surface of Mars using a wind-driven network of mobile sensors- Gone with the Wind ON_Mars (GOWON). GOWON is a scalable architecture that will allow in-situ mapping of a wide range of phenomena, exploiting existing capabilities, but radically improving our ability to study Mars. GOWON has the following characteristics: 1.it consists of a dynamic wireless network of many compact mobile sensors. 2.the mobile sensors (called moballs) are spherically-shaped and wind-driven; they are lightweight and bouncy. 3. moballs communicate with each other and earth through a satellite system orbiting Mars. There is also peer-to-peer communication between the moballs, creating a network of shared data, computing, and tasks. Motivation and Rationale Thanks to earlier exploration missions to Mars we now have a much better understanding of many of the natural characteristics of the red planet. We now know that there is an abundance of wind (with average speeds of 10 m/s and much hig...

  20. Polygonal terrains on Mars

    Directory of Open Access Journals (Sweden)

    Pedro Pina

    2009-06-01

    Full Text Available The presence of water ice on Mars is well established. Some featureson the planet point to the occurrence of processes similar to those that take place in periglacial areas of Earth. One of the clues for this is the existence of small-scale polygonal terrains. In this paper, we present a methodology that aims at the automated identification of polygonal patterns on high-spatial resolution images of the surface of Mars. In the context of the research project TERPOLI, this step will be complemented with a full characterization, in both geometric and topological terms, of thenetworks detected. In this manner, we hope to collect data that will lead to a better understanding of the conditions of formation of the polygons, and of their temporal evolution; namely, we intend to identify different groups of polygons and to compare them with terrestrial examples.

  1. The politics of Mars

    Science.gov (United States)

    Schmitt, Harrison H.

    1986-01-01

    A discussion is presented comparing past and present major accomplishments of the U.S. and the Soviet Union in space. It concludes that the Soviets are presently well ahead of the U.S. in several specific aspects of space accomplishment and speculates that the Soviet strategy is directed towards sending a man to the vicinity of Mars by the end of this century. A major successful multinational space endeavor, INTELSAT, is reviewed and it is suggested that the manned exploration of Mars offers a unique opportunity for another such major international cooperative effort. The current attitude of U.S. leadership and the general public is assessed as uniformed or ambivalent about the perceived threat of Soviet dominance in space.

  2. Geophysics of Mars

    Science.gov (United States)

    Wells, R. A.

    1979-01-01

    A physical model of Mars is presented on the basis of light-scattering observations of the Martian atmosphere and surface and interior data obtained from observations of the geopotential field. A general description of the atmosphere is presented, with attention given to the circulation and the various cloud types, and data and questions on the blue haze-clearing effect and the seasonal darkening wave are summarized and the Mie scattering model developed to explain these observations is presented. The appearance of the planet from earth and spacecraft through Mariner 9 is considered, and attention is given to the preparation of topographical contour maps, the canal problem and large-scale lineaments observed from Mariner 9, the gravity field and shape of the planet and the application of Runcorn's geoid/convection theory to Mars. Finally, a summary of Viking results is presented and their application to the understanding of Martian geophysics is discussed.

  3. ACCESS Mars: A Mission Architecture for an initial settlement on Mars; using caves as habitation

    Science.gov (United States)

    Perez-Poch, Antoni; Gallardo, Beatriz; Laufer, Ren; Zavaleta, Jhony; Davila, Alfonso; de Carufel, Guy; Antonakopoulos, Konstantinos; Husseini, A. Al; Alvarez Sánchez, L.; Antonakopoulos, K.; Apeldoorn, J.; Ashford, K., Jr.; Atabay, D.; Barrios, I.; Baydaroglu, Y.; Bennell, K. M.; Chen, J.; Chen, X.; Cormier, D.; Crowley, P.; de Carufel, G.; Deper, B.; Drube, L.; Duffy, P.; Edwards, P.; Gutiérrez Fernandez, E.; Haider, O.; Kumar, G.; Henselowsky, C.; Hirano, D.; Hirmer, T.; Hogan, B.; Albalat, A. Jaime; Jens, E.; Jivenescu, I.; Jojaghaian, A.; Kerrigan, M.; Kodachi, Y.; Langston, S.; Macintosh, R.; Miguélez, X.; Panek, N.; Pegg, C.; Peldszus, R.; Peng, X.; Perez-Poch, A.; Perron, A.; Qiu, J.; Renten, P.; Ricardo, J.; Saraceno, T.; Sauceda, F.; Shaghaghi Varzeghani, A.; Shimmin, R.; Solaz, R.; Solé, A.; Suresh, E. R.; Mar Vaquero Escribano, T.; Vargas Muñoz, M.; Vaujour, P. D.; Zeile, D. Veilette, Y. Winetraub, O.

    This paper summarizes a team project report produced during the Summer Space Program of the International Space University, held at Nasa-Ames Research Center (CA, USA) by 56 students from 15 countries. Chair of the team project was Rene Laufer. Facilitators were Alfonso Davila and Jhonny Zavaleta, and teacher associate supporting the team was Beatriz Gallardo. The human race has evolved, grown and expanded through the exploration of Earth. After initial steps on the Moon, our next challenge is to explore the solar system. Mars shows potential for both scientific discovery and future human settlement, and therefore represents a prime candidate for the next leap of human exploration. Such a bold endeavor will be a driver for an unprecedented worldwide cooperative effort and the catalyst for a new era of international, intercultural and interdisciplinary human relations. Scientific and technological progress will also accelerate as mankind is ushered into a new era of space exploration. Currently proposed Mars missions have identified a number of challenges such as high levels of radiation, harsh climate and limited launch windows. Recently discovered lava tubes on Mars present potential solutions to some of these issues, but raise a variety of intriguing new challenges. This paper reviews existing reference missions and identifies areas of further research essential for adapting mission architectures to utilize caves. Different mission scenarios are proposed and analyzed, with a number of different recommendations given. An analysis of the feasibility of using Martian lava tubes as habitation is given in another paper by the same authors at COSPAR 2010 F34 Technical Session. Literature suggests a low radiation environment within Martian caves, allowing for extended duration missions. The ACCESS Mars Team concludes that the use of lava tubes as human habitats will be more beneficial for human Mars exploration than currently proposed surface solutions.

  4. Increasing Diversity in Global Climate Change, Space Weather and Space Technology Research and Education

    Science.gov (United States)

    Johnson, L. P.; Austin, S. A.; Howard, A. M.; Boxe, C.; Jiang, M.; Tulsee, T.; Chow, Y. W.; Zavala-Gutierrez, R.; Barley, R.; Filin, B.; Brathwaite, K.

    2015-12-01

    This presentation describes projects at Medgar Evers College of the City University of New York that contribute to the preparation of a diverse workforce in the areas of ocean modeling, planetary atmospheres, space weather and space technology. Specific projects incorporating both undergraduate and high school students include Assessing Parameterizations of Energy Input to Internal Ocean Mixing, Reaction Rate Uncertainty on Mars Atmospheric Ozone, Remote Sensing of Solar Active Regions and Intelligent Software for Nano-satellites. These projects are accompanied by a newly developed Computational Earth and Space Science course to provide additional background on methodologies and tools for scientific data analysis. This program is supported by NSF award AGS-1359293 REU Site: CUNY/GISS Center for Global Climate Research and the NASA New York State Space Grant Consortium.

  5. Organics on Mars?

    Science.gov (United States)

    ten Kate, Inge L

    2010-01-01

    Organics are expected to exist on Mars based on meteorite infall, in situ production, and any possible biological sources. Yet they have not been detected on the martian surface; are they there, or are we not capable enough to detect them? The Viking gas chromatograph-mass spectrometer did not detect organics in the headspace of heated soil samples with a detection limit of parts per billion. This null result strongly influenced the interpretation of the reactivity seen in the Viking biology experiments and led to the conclusion that life was not present and, instead, that there was some chemical reactivity in the soil. The detection of perchlorates in the martian soil by instruments on the Phoenix lander and the reports of methane in the martian atmosphere suggest that it may be time to reconsider the question of organics. The high-temperature oxidizing properties of perchlorate will promote combustion of organics in pyrolytic experiments and may have affected the ability of both Phoenix's organic analysis experiment and the Viking mass spectrometer experiments to detect organics. So the question of organics on Mars remains open. A primary focus of the upcoming Mars Science Laboratory will be the detection and identification of organic molecules by means of thermal volatilization, followed by gas chromatography-mass spectrometry--as was done on Viking. However, to enhance organic detectability, some of the samples will be processed with liquid derivatization agents that will dissolve organics from the soil before pyrolysis, which may separate them from the soil perchlorates. Nonetheless, the problem of organics on Mars is not solved, and for future missions other organic detection techniques should therefore be considered as well.

  6. Meteorites from Mars

    Science.gov (United States)

    Grady, M.; Murdin, P.

    2002-01-01

    The SNC METEORITES, named after the initials of the first discovered members (Shergotty, Nakhla and Chassigny), are a group of stony meteorites that are thought to come from Mars, rather than the asteroid belt. They are all igneous rocks (i.e. formed by crystallizing from molten material) and are distinguished from other meteorites by their ages, which are as low as 165 million years old. A young...

  7. Chemical Thermodynamics on Mars

    Science.gov (United States)

    Selco, Jodye I.

    1995-07-01

    This seven question take-home exam guides the students through a marathon problem to arrive at a single answer to the overall question: "How sensitive a probe do you need in order to detect signs of "life" (methane produced by bacteria instead of by chemical equilibrium) on Mars". This exam was originally written to correspond to chapters four through seven in Ira Levine's Physical Chemistry, 3rd edition, McGraw Hill, New York, 1988.

  8. Carving intracrater layered deposits with wind on Mars

    Science.gov (United States)

    Day, M.; Anderson, W.; Kocurek, G.; Mohrig, D.

    2016-03-01

    Crater basins on Mars host thick sedimentary sequences, which record the environments of early Mars. These basin fills commonly exhibit mound morphologies thought to arise from aeolian erosion of initially crater filling strata. This study presents transport-based models explaining how mounds could be carved by wind. Wind tunnel experiments generated morphologies similar to those observed on Mars, and numerical modeling of flow over a crater using large-eddy simulation (LES) demonstrated a positive feedback between topographic focusing of flow and erosion potential. Observations of yardangs, dunes, and wind streaks, all proxies for wind direction, largely agree with model results. Where mound strata origins have been interpreted, basal subaqueous deposits are overlain by aeolian deposits. This stratigraphic progression, culminating in wind-driven excavation, is consistent with a global desiccation event. The occurrence of sedimentary mounds only on Noachian terrain argues that this event was related to late Noachian climatic change.

  9. Supervolcanoes within an ancient volcanic province in Arabia Terra, Mars.

    Science.gov (United States)

    Michalski, Joseph R; Bleacher, Jacob E

    2013-10-03

    Several irregularly shaped craters located within Arabia Terra, Mars, represent a new type of highland volcanic construct and together constitute a previously unrecognized Martian igneous province. Similar to terrestrial supervolcanoes, these low-relief paterae possess a range of geomorphic features related to structural collapse, effusive volcanism and explosive eruptions. Extruded lavas contributed to the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulphur and erupted fine-grained pyroclastics from these calderas probably fed the formation of altered, layered sedimentary rocks and fretted terrain found throughout the equatorial region. The discovery of a new type of volcanic construct in the Arabia volcanic province fundamentally changes the picture of ancient volcanism and climate evolution on Mars. Other eroded topographic basins in the ancient Martian highlands that have been dismissed as degraded impact craters should be reconsidered as possible volcanic constructs formed in an early phase of widespread, disseminated magmatism on Mars.

  10. Drill/borescope System for the Mars Polar Pathfinder

    Science.gov (United States)

    Paige, D. A.; Wood, S. E.; Vasavada, A. R.

    1993-01-01

    The primary goals of the Mars Polar Pathfinder (MPP) Discovery Mission are to characterize the composition and structure of Mars' north polar ice cap, and to determine whether a climate record may be preserved in layers of ice and dust. The MPP would land as close as possible to the geographic north pole of Mars and use a set of instruments similar to those used by glaciologists to study polar ice caps on Earth: a radar sounder, a drill/borescope system, and a thermal probe. The drill/borescope system will drill approximately 50 cm into the surface and image the sides of the hole at 10 micron resolution for compositional and stratigraphic analysis. Several uncertainties have guided the development of this instrument, and they are discussed.

  11. Exobiological exploration of Mars

    Science.gov (United States)

    Klein, H. P.; Devincenzi, D. L.

    1995-01-01

    Of all the other planets in the solar system, Mars remains the most promising for further elucidating concepts about chemical evolution and the origin of life. Strategies were developed to pursue three exobiological objectives for Mars exploration: determining the abundance and distribution of the biogenic elements and organic compounds, detecting evidence of an ancient biota on Mars, and determining whether indigenous organisms exist anywhere on the planet. The three strategies are quite similar and, in fact, share the same sequence of phases. In the first phase, each requires global reconnaissance and remote sensing by orbiters to select sites of interest for detailed in situ analyses. In the second phase, lander missions are conducted to characterize the chemical and physical properties of the selected sites. The third phase involves conducting 'critical' experiments at sites whose properties make them particularly attractive for exobiology. These critical experiments would include, for example, identification of organics, detection of fossils, and detection of extant life. The fourth phase is the detailed analysis of samples returned from these sites in Earth-based laboratories to confirm and extend previous discoveries. Finally, in the fifth phase, human exploration is needed to establish the geological settings for the earlier findings or to discover and explore sites that are not accessible to robotic spacecraft.

  12. Mars Rocket Propulsion System

    Science.gov (United States)

    Zubrin, Robert; Harber, Dan; Nabors, Sammy

    2008-01-01

    A report discusses the methane and carbon monoxide/LOX (McLOx) rocket for ascent from Mars as well as other critical space propulsion tasks. The system offers a specific impulse over 370 s roughly 50 s higher than existing space-storable bio-propellants. Current Mars in-situ propellant production (ISPP) technologies produce impure methane and carbon monoxide in various combinations. While separation and purification of methane fuel is possible, it adds complexity to the propellant production process and discards an otherwise useful fuel product. The McLOx makes such complex and wasteful processes unnecessary by burning the methane/CO mixtures produced by the Mars ISPP systems without the need for further refinement. Despite the decrease in rocket-specific impulse caused by the CO admixture, the improvement offered by concomitant increased propellant density can provide a net improvement in stage performance. One advantage is the increase of the total amount of propellant produced, but with a decrease in mass and complexity of the required ISPP plant. Methane/CO fuel mixtures also may be produced by reprocessing the organic wastes of a Moon base or a space station, making McLOx engines key for a human Lunar initiative or the International Space Station (ISS) program. Because McLOx propellant components store at a common temperature, very lightweight and compact common bulkhead tanks can be employed, improving overall stage performance further.

  13. Guidelines for 2007 MARS exercise

    CERN Multimedia

    HR Department

    2007-01-01

    Following the introduction of the new Merit Appraisal and Recognition Scheme (MARS), full details of the scheme are now available via the HR Department's homepage or directly on the Department's MARS web page: in English: http://humanresources.web.cern.ch/HumanResources/internal/personnel/pmd/cr/MARS.asp or French: http://humanresources.web.cern.ch/humanresources/internal/personnel/pmd/cr/mars_fr.asp You will find on this page: 'Introduction to MARS' with detailed information presented in Frequently Asked Questions; these include the MARS timetable for proposals and decisions; 'Regulations' with links to the scheme's statutory documents; 'Procedures and Forms' and 'Useful Information' with links to all the relevant documentation; these include the mandates of the Senior Staff Advisory Committee (SSAC) and the Technical Engineers and Administrative Careers Committee (TEACC). HR Department Tel. 73566

  14. Late Tharsis Formation and New Perspesctives for Early Mars

    Science.gov (United States)

    Bouley, Sylvain; Baratoux, David; Matsuyama, Isamu; Forget, Francois; Séjourné, Antoine; Turbet, Martin; Costard, Francois

    2016-04-01

    The Tharsis bulge is the largest volcanic complex on Mars and the associated excess of Mars has likely driven a True Polar Wander which has moved the province close to the present equator [1,2]. It has been suggested that the Tharsis load on the lithosphere influenced the orientation of the Noachian/Early Hesperian (>3.5 Ga) valley networks and therefore that most of its topography was completed before their incision during the Noachian era (> 3.7 Ga) [3]. We calculated the rotational figure of Mars and its surface topography before Tharsis, when the spin-axis of the planet was controlled by the hemispheric dichotomy. We show that the observed directions of valley networks are consistent with topographic gradients in this configuration and thus do not require the presence of the Tharsis load. Furthermore, their distribution along a small circle tilted with respect to the equator is found to correspond to a regular south tropical band in the pre-TPW geographic frame. Preferential accumulation of ice or water in a south tropical band is predicted by Early Mars climate model simulations applied to the pre-TPW topography [2,4]. This study implies a major overhaul of the relative chronology of the main events affecting the Mars geological and climatic history during the Noachian and Hesperian periods. A late rise of Tharsis, contemporaneous with fluvial activity, argues for a causal link between volcanic outgassing and the stability of superficial liquid water. The revised chronology, the topography and planet's configuration before Tharsis offers new perspectives to examine the surface conditions with respect to Early Mars habitability. References: [1] Matsuyama, I. & Manga (2010), JGR Planets, 115, 12020. [2] Bouley et al., accepted for publication In Nature. [3] Phillips, R.J. et al. (2001), Science, 291, 2587-2591. [4] Wordsworth et al. (2015), JGR Planets, 120, 1201-1219.

  15. Satellite data compression

    CERN Document Server

    Huang, Bormin

    2011-01-01

    Satellite Data Compression covers recent progress in compression techniques for multispectral, hyperspectral and ultra spectral data. A survey of recent advances in the fields of satellite communications, remote sensing and geographical information systems is included. Satellite Data Compression, contributed by leaders in this field, is the first book available on satellite data compression. It covers onboard compression methodology and hardware developments in several space agencies. Case studies are presented on recent advances in satellite data compression techniques via various prediction-

  16. Trends in communications satellites

    CERN Document Server

    Curtin, Denis J

    1979-01-01

    Trends in Communications Satellites offers a comprehensive look at trends and advances in satellite communications, including experimental ones such as NASA satellites and those jointly developed by France and Germany. The economic aspects of communications satellites are also examined. This book consists of 16 chapters and begins with a discussion on the fundamentals of electrical communications and their application to space communications, including spacecraft, earth stations, and orbit and wavelength utilization. The next section demonstrates how successful commercial satellite communicati

  17. Carl Sagan and the Exploration of Mars and Venus

    Science.gov (United States)

    Toon, Owen B.; Condon, Estelle P. (Technical Monitor)

    1997-01-01

    Inspired by childhood readings of books by Edgar Rice Burroughs, Carl Sagan's first interest in planetary science focused on Mars and Venus. Typical of much of his career he was skeptical of early views about these planets. Early in this century it was thought that the Martian wave of darkening, a seasonal albedo change on the planet, was biological in origin. He suggested instead that it was due to massive dust storms, as was later shown to be the case. He was the first to recognize that Mars has huge topography gradients across its surface. During the spacecraft era, as ancient river valleys were found on the planet, he directed studies of Mars' ancient climate. He suggested that changes in the planets orbit were involved in climate shifts on Mars, just as they are on Earth. Carl had an early interest in Venus. Contradictory observations led to a controversy about the surface temperature, and Carl was one of the first to recognize that Venus has a massive greenhouse effect at work warming its surface. His work on radiative transfer led to an algorithm that was extensively used by modelers of the Earth's climate and whose derivatives still dominate the calculation of radiative transfer in planetary atmospheres today. Carl inspired a vast number of young scientists through his enthusiasm for new ideas and discoveries, his skeptical approach, and his boundless energy. I had the privilege to work in Carl's laboratory during the peak of the era of Mars' initial exploration. It was an exciting time, and place. Carl made it a wonderful experience.

  18. Modeling calcium sulfate chemistries with applications to Mars

    Science.gov (United States)

    Marion, G. M.; Catling, D. C.; Kargel, J. S.; Crowley, J. K.

    2016-11-01

    available by removing phases that may have kinetically inhibited formation. Removing anhydrite allows bassanite to precipitate at 373 K, followed by gypsum at 351 K (78 °C), and epsomite at 277 K. Removing anhydrite and gypsum allows bassanite to form from 373 to 273 K. But bassanite formation from warm to cold temperatures does not seem appropriate for Mars and Earth. An explanation for spatial patterns of gypsum, anhydrite, and bassanite on Mars and Earth could be past environmental differences. Anhydrite and bassanite are favored near Mars' equator with higher temperatures, along with drier, more saline, and more acidic environments. Gypsum would be favored at the lower temperatures in the Mars polar region with wetter, lower salinity, and less acidic environments. On Earth, Ca-sulfate would likely over time largely finish re-precipitating as the more insoluble gypsum. But Mars was not in long-term moderate climates compared to Earth that strongly influenced the dominance of gypsum on Earth. So while temperature and water/acid environments for CaSO4 minerals on Mars may have been a major factor for these precipitations, the short-term moderate climates on Mars may also have influenced the prevalence of higher soluble CaSO4 species in the lower Mars latitudes.

  19. Lybia Montes: A Safe, Ancient Cratered Terrain, Mars Surveyor Landing Site at the Isidis Basin Rim

    Science.gov (United States)

    Haldemann, A. F. C.; Anderson, R. C.; Harbert, W.

    2000-01-01

    The Isidis basin rim may be key to understanding Mars' past with future lander missions: this area enables the mission objective to explore Mars' climatic and geologic history, including the search for liquid water and evidence of prior or extant life in ancient terrains. While two safe candidate landIng sites for Mars Pathfinder were identified in Isidis Planitia, and one is being pursued for the Mars Surveyor 2001 Lander, the region around Isidis Planitia. in contrast to Tharsis for example, has only been lightly studied. The advent of new high resolution data sets provides an opportunity to re-assess the geologic context of this Impact basin and its rim within the Martian geologic sequence as a candidate site for studying Mars' ancient cratered terrain and ancient hydrosphere. This reexamination is warranted by the various hypotheses that Isidis was once filled with ice or water.

  20. The introduction to GNOS instrument for FY-3 satellite

    Science.gov (United States)

    Du, Qifei

    2016-07-01

    Global Navigation Satellite System (GNSS) Radio occultation (RO) has become a major atmospheric and ionospheric remote sensing technique and been widely used for numerical weather prediction and global climate monitoring applications. The first GNSS Occultation Sounder (GNOS) developed and manufactured by National Space Science Center (NSSC), Chinese Academy of Science is a RO payload, which has been onboard Fengyun-3 C (FY-3C) satellite and been launched on September 23, 2013. FY-3 series satellites are the Chinese second generation polar-orbiting meteorological satellites with sun-synchronous orbits. During RO events, the GNOS instruments measure the phase delay caused by the Earth's atmospheric and ionospheric refraction between the GNSS satellites and FY-3 satellites, as the relative position between the GNSS satellites and the FY-3 satellites varying, vertical profiles of RO observations (i.e. phase and amplitude) will be obtained, which can be used to derived the atmospheric and ionospheric physical properties such as press, temperature, humidity and ionospheric electron density. In my presentation, we present the characteristics of GNOS instruments for FY-3 series satellites and the result by the instrument in orbit. Firstly, we present the characteristics of GNOS instrument for FY-3C satellite and its precision of atmosphere occultation data. Additionally, we introduce the characteristics of GNOS instrument for FY-3D satellite which will be launched in 2016. Finally, we show the next generation GNOS instrument and its characteristics for the following FY-3 satellites.

  1. Planetary science: are there active glaciers on Mars?

    Science.gov (United States)

    Gillespie, Alan R; Montgomery, David R; Mushkin, Amit

    2005-12-08

    Head et al. interpret spectacular images from the Mars Express high-resolution stereo camera as evidence of geologically recent rock glaciers in Tharsis and of a piedmont ('hourglass') glacier at the base of a 3-km-high massif east of Hellas. They attribute growth of the low-latitude glaciers to snowfall during periods of increased spin-axis obliquity. The age of the hourglass glacier, considered to be inactive and slowly shrinking beneath a debris cover in the absence of modern snowfall, is estimated to be more than 40 Myr. Although we agree that the maximum glacier extent was climatically controlled, we find evidence in the images to support local augmentation of accumulation from snowfall through a mechanism that does not require climate change on Mars.

  2. Volcanism on the Red Planet: Mars. Chapter 4

    Science.gov (United States)

    Greeley, Ronald; Bridges, Nathan T.; Crown, David A.; Crumpler, Larry S.; Fagents, Sarah A.; Mouginis-Mark, Peter J.; Zimbelman, James R.

    2000-01-01

    Of all the planets in the Solar System, Mars is the most Earthlike in its geological characteristics. Like Earth, it has been subjected to exogenic processes, such as impact cratesing and erosion by wind and water, as well as endogenic processes, including tectonic deformation of the crust and volcanism. The effects of these processes are amply demonstrated by the great variety of surface features, including impact craters, landslides, former river channels, sand dunes, and the largest volcanoes in the Solar System. Some of these features suggest substantial changes in Mars' environment during its history. For example, as reviewed by Carr, today Mars is a cold, dry desert with an average atmospheric pressure of only 5.6 mbar which does not allow liquid water to exist on the surface. To some planetary scientists, the presence of the channels bespeaks a time when Mars was warmer and wetter. However, others have argued that these features might have formed under current conditions and that there might not have been a shift in climate. Could the morphology of volcanoes and related features provide clues to past Martian environments? What role is played by atmospheric density in the styles of eruptions on Mars and resulting landforms? If these and related questions can be answered, then we may have a means for assessing the conditions on Mars' surface in the past and comparing the results with models of Martian evolution. In this chapter, we outline the sources of information available for volcanism on Mars, explore the influence of the Martian environment on volcanic processes, and describe the principal volcanic features and their implications for understanding the general evolution of the Martian surface.

  3. Volcanism on the Red Planet: Mars. Chapter 4

    Science.gov (United States)

    Greeley, Ronald; Bridges, Nathan T.; Crown, David A.; Crumpler, Larry S.; Fagents, Sarah A.; Mouginis-Mark, Peter J.; Zimbelman, James R.

    2000-01-01

    Of all the planets in the Solar System, Mars is the most Earthlike in its geological characteristics. Like Earth, it has been subjected to exogenic processes, such as impact cratesing and erosion by wind and water, as well as endogenic processes, including tectonic deformation of the crust and volcanism. The effects of these processes are amply demonstrated by the great variety of surface features, including impact craters, landslides, former river channels, sand dunes, and the largest volcanoes in the Solar System. Some of these features suggest substantial changes in Mars' environment during its history. For example, as reviewed by Carr, today Mars is a cold, dry desert with an average atmospheric pressure of only 5.6 mbar which does not allow liquid water to exist on the surface. To some planetary scientists, the presence of the channels bespeaks a time when Mars was warmer and wetter. However, others have argued that these features might have formed under current conditions and that there might not have been a shift in climate. Could the morphology of volcanoes and related features provide clues to past Martian environments? What role is played by atmospheric density in the styles of eruptions on Mars and resulting landforms? If these and related questions can be answered, then we may have a means for assessing the conditions on Mars' surface in the past and comparing the results with models of Martian evolution. In this chapter, we outline the sources of information available for volcanism on Mars, explore the influence of the Martian environment on volcanic processes, and describe the principal volcanic features and their implications for understanding the general evolution of the Martian surface.

  4. Milliwatt radioisotope power supply for the PASCAL Mars surface stations

    Science.gov (United States)

    Allen, Daniel T.; Murbach, Marcus S.

    2001-02-01

    A milliwatt power supply is being developed based on the 1 watt Light-Weight Radioisotope Heater Unit (RHU), which has already been used to provide heating alone on numerous spacecraft. In the past year the power supply has been integrated into the design of the proposed PASCAL Mars Network Mission, which is intended to place 24 surface climate monitoring stations on Mars. The PASCAL Mars mission calls for the individual surface stations to be transported together in one spacecraft on a trajectory direct from launch to orbit around Mars. From orbit around Mars each surface station will be deployed on a SCRAMP (slotted compression ramp) probe and, after aerodynamic and parachute deceleration, land at a preselected location on the planet. During descent sounding data and still images will be accumulated, and, once on the surface, the station will take measurements of pressure, temperature and overhead atmospheric optical depth for a period of 10 Mars years (18.8 Earth years). Power for periodic data acquisition and transmission to orbital then to Earth relay will come from a bank of ultracapacitors which will be continuously recharged by the radioisotope power supply. This electronic system has been designed and a breadboard built. In the ultimate design the electronics will be arrayed on the exterior surface of the radioisotope power supply in order to take advantage of the reject heat. This assembly in turn is packaged within the SCRAMP, and that assembly comprises the surface station. An electrically heated but otherwise prototypical power supply was operated in combination with the surface station breadboard system, which included the ultracapacitors. Other issues addressed in this work have been the capability of the generator to withstand the mechanical shock of the landing on Mars and the effectiveness of the generator's multi-foil vacuum thermal insulation. .

  5. Numerical modeling of wind-blown sand on Mars.

    Science.gov (United States)

    Huang, HaoJie; Bo, TianLi; Zheng, XiaoJing

    2014-09-01

    Recent observation results show that sand ripples and dunes are movable like those on Earth under current Martian climate. And the aeolian process on Mars therefore is re-attracting the eyes of scientific researchers in different fields. In this paper, the spatial and temporal evolution of wind-blown sand on Mars is simulated by the large-eddy simulation method. The simulations are conducted under the conditions of both friction wind speed higher and lower than the "fluid threshold", respectively. The fluid entrainment of the sand particles, the processes among saltation sand particles and sand bed, and the negative feedback of sand movement to flow field are considered. Our results show that the "overshoot" phenomenon also exists in the evolution of wind-blown sand on Mars both temporally and spatially; impact entrainment affects the sand transport rate on Mars when the wind speed is smaller or larger than the fluid threshold; and both the average saltation length and height are one order of magnitudes larger than those on Earth. Eventually, the formulas describing the sand transport rate, average saltation length and height on Mars are given, respectively.

  6. DYNAMO: a Mars upper atmosphere package for investigating solar wind interaction and escape processes, and mapping Martian fields

    DEFF Research Database (Denmark)

    Chassefiere, E.; Nagy, A.; Mandea, M.

    2004-01-01

    DYNAMO is a small multi-instrument payload aimed at characterizing current atmospheric escape, which is still poorly constrained, and improving gravity and magnetic field representations, in order to better understand the magnetic, geologic and thermal history of Mars. The internal structure...... and evolution of Mars is thought to have influenced climate evolution. The collapse of the primitive magnetosphere early in Mars history could have enhanced atmospheric escape and favored transition to the present and climate. These objectives are achieved by using a low periapsis orbit. DYNAMO has been...... proposed in response to the AO released in February 2002 for instruments to be flown as a complementary payload onboard the CNES Orbiter to Mars (MO-07), foreseen to be launched in 2007 in the framework of the French PREMIER Mars exploration program. MO-07 orbital phase 2b (with an elliptical orbit...

  7. Astrometric observations of Phobos and Deimos during the 1971 opposition of Mars

    CERN Document Server

    Robert, V; Pascu, D; Arlot, J -E; De Cuyper, J -P; Dehant, V; Thuillot, W

    2015-01-01

    Accurate positional measurements of planets and satellites are used to improve our knowledge of their dynamics and to infer the accuracy of planet and satellite ephemerides. In the framework of the FP7 ESPaCE project, we provide the positions of Mars, Phobos, and Deimos taken with the U.S. Naval Observatory 26-inch refractor during the 1971 opposition of the planet. These plates were measured with the digitizer of the Royal Observatory of Belgium and reduced through an optimal process that includes image, instrumental, and spherical corrections to provide the most accurate data. We compared the observed positions of the planet Mars and its satellites with the theoretical positions from INPOP10 and DE430 planetary ephemerides, and from NOE and MAR097 satellite ephemerides. The rms residuals in RA and Dec. of one position is less than 60 mas, or about 20 km at Mars. This accuracy is comparable to the most recent CCD observations. Moreover, it shows that astrometric data derived from photographic plates can comp...

  8. Cosmic rays, clouds, and climate

    DEFF Research Database (Denmark)

    Marsh, N.; Svensmark, Henrik

    2000-01-01

    cloud radiative properties. Thus, a moderate influence on atmospheric aerosol distributions from cosmic ray ionisation would have a strong influence on the Earth's radiation budget. Historical evidence over the past 1000 years indicates that changes in climate have occurred in accord with variability...... in the Earth's radiation budget through trapping outgoing radiation and reflecting incoming radiation. If a physical link between these two features can be established, it would provide a mechanism linking solar activity and Earth's climate. Recent satellite observations have further revealed a correlation...... in cosmic ray intensities. Such changes are in agreement with the sign of cloud radiative forcing associated with cosmic ray variability as estimated from satellite observations....

  9. The Geomorphology of Lyot crater,Mars

    Science.gov (United States)

    Balme, Matthew; Gallagher, Colman; Conway, Susan

    2013-04-01

    Lyot crater, Mars, is a relatively young (ii) studies of glacial and periglacial environments useful for studying water on Mars throughout its history. Here we present preliminary mapping of the various ice- and water-related landforms found in and around Lyot crater. Of particular interest are polygonal networks of metre-scale clasts (perhaps periglacial in origin?) and a variety of channels, fans and lobate flows that could be interpreted as proglacial fluvial systems [2]. The putative glacial assemblage exists within the crater rim and in high relief areas outside of the crater. Fluvial-like channels and fans are seen both within the crater and on the ejecta blanket. The networks of polygonal clasts occur only on the margins of the continuous ejecta blanket, at a radial distance of about 300 km from the crater's centre. The clastic polygons that compose the networks are found only on the Eastern side of Lyot basin, and extend in a broad swathe from about nor-northwest to southwest of the crater. The polygons are generally one to two hundred metres in diameter and consist of lines of clasts (sometime double lines) with flat, low centre-regions between them. Their spatial distribution strongly indicates that they have a genetic link to the formation of the impact crater. Our working hypothesis is that the glacial/fluvial assemblages are related to climate-controlled deposition of ice, with later flow and probably thaw as well. The polygonal clast network is harder to explain, but could reflect the location of water ice-rich zones of the ejecta blanket. Hence, this could be material excavated from the cryosphere during impacts and then reworked by periglacial processes at a much later time. [1] Harrison, T.N., et al., Impact-induced overland fluid flow and channelized erosion at Lyot Crater, Mars. Geophys. Res. Let., 2010. 37(L21201): doi:10.1029/2010GL045074 [2] Dickson, J.L., et al., Amazonian-aged fluvial valley systems in a climatic microenvironment on Mars

  10. A Sunphotometer for Mars Atmosphere Studies

    Science.gov (United States)

    Strawa, A. W.; Velante, M.; Colaprete, A.; Papadopoulos, P.

    2005-12-01

    The interaction between the sun's energy and Martian dust is recognized as one of the biggest driving forces for climate on Mars, yet not enough is known about the physical and optical properties of this dust or its spatial and temporal variation. A better understanding of the interaction between Mars dust and its weather and climate is required for manned exploration. Recognizing this, we are developing an instrument concept that would enable dedicated measurements to characterize Mars' atmosphere and dust than has been possible in the past. The instrument is based on the sunphotometer concept, integrating concepts that produce an instrument with no moving parts. Consequently, it would be small, light weight, and consume little electrical power. Sunphotometer's are commonly used on the Earth's surface, as well as on aircraft, to determine the solar energy attenuated by gases and aerosol particles in the atmosphere. Typically, these instruments track the sun to measure the direct solar attenuation. Our concept uses a combination of unique optics and a detector array to eliminate the moving parts and make the instrument much smaller, compact, and reliable. Data products would include downwelling flux, gas and aerosol optical depth at multiple-wavelengths, gas phase constituent column density, and aerosol size distribution. One of the desirable features of this concept is that the techniques exist that would enable the instrument to be self-calibrating throughout the year. This means that as dust begins to deposit on the instrument window, or the electronics or sensor array degrade, the instrument could be periodically recalibrated in situ. Thus it would provide invaluable data for long-term modeling efforts. This system would also be able to compensate for deployment on non-level surfaces. This instrument would have applicability to the Discovery and Mars Exploration class Missions. The instrument would be a valuable component in the exploration of any planetary

  11. Astrobiology through the ages of Mars: the study of terrestrial analogues to understand the habitability of Mars.

    Science.gov (United States)

    Fairén, Alberto G; Davila, Alfonso F; Lim, Darlene; Bramall, Nathan; Bonaccorsi, Rosalba; Zavaleta, Jhony; Uceda, Esther R; Stoker, Carol; Wierzchos, Jacek; Dohm, James M; Amils, Ricardo; Andersen, Dale; McKay, Christopher P

    2010-10-01

    Mars has undergone three main climatic stages throughout its geological history, beginning with a water-rich epoch, followed by a cold and semi-arid era, and transitioning into present-day arid and very cold desert conditions. These global climatic eras also represent three different stages of planetary habitability: an early, potentially habitable stage when the basic requisites for life as we know it were present (liquid water and energy); an intermediate extreme stage, when liquid solutions became scarce or very challenging for life; and the most recent stage during which conditions on the surface have been largely uninhabitable, except perhaps in some isolated niches. Our understanding of the evolution of Mars is now sufficient to assign specific terrestrial environments to each of these periods. Through the study of Mars terrestrial analogues, we have assessed and constrained the habitability conditions for each of these stages, the geochemistry of the surface, and the likelihood for the preservation of organic and inorganic biosignatures. The study of these analog environments provides important information to better understand past and current mission results as well as to support the design and selection of instruments and the planning for future exploratory missions to Mars.

  12. MetNet Precursor - Network Mission to Mars

    Science.gov (United States)

    Harri, Arri-Matti

    2010-05-01

    We are developing a new kind of planetary exploration mission for Mars - MetNet in situ observation network based on a new semi-hard landing vehicle called the Met-Net Lander (MNL). The first MetNet vehicle, MetNet Precursor, slated for launch in 2011. The MetNet development work started already in 2001. The actual practical Precursor Mission development work started in January 2009 with participation from various space research institutes and agencies. The scientific rationale and goals as well as key mission solutions will be discussed. The eventual scope of the MetNet Mission is to deploy some 20 MNLs on the Martian surface using inflatable descent system structures, which will be supported by observations from the orbit around Mars. Currently we are working on the MetNet Mars Precursor Mission (MMPM) to deploy one MetNet Lander to Mars in the 2011 launch window as a technology and science demonstration mission. The MNL will have a versatile science payload focused on the atmospheric science of Mars. Time-resolved in situ Martian meteorological measurements acquired by the Viking, Mars Pathfinder and Phoenix landers and remote sensing observations by the Mariner 9, Viking, Mars Global Surveyor, Mars Odyssey and the Mars Express orbiters have provided the basis for our current understanding of the behavior of weather and climate on Mars. However, the available amount of data is still scarce and a wealth of additional in situ observations are needed on varying types of Martian orography, terrain and altitude spanning all latitudes and longitudes to address microscale and mesoscale atmospheric phenomena. Detailed characterization of the Martian atmospheric circulation patterns and climatological cycles requires simultaneous in situ atmospheric observations. The scientific payload of the MetNet Mission encompasses separate instrument packages for the atmospheric entry and descent phase and for the surface operation phase. The MetNet mission concept and key probe

  13. Venus-Earth-Mars: comparative climatology and the search for life in the solar system.

    Science.gov (United States)

    Launius, Roger D

    2012-09-19

    Both Venus and Mars have captured the human imagination during the twentieth century as possible abodes of life. Venus had long enchanted humans-all the more so after astronomers realized it was shrouded in a mysterious cloak of clouds permanently hiding the surface from view. It was also the closest planet to Earth, with nearly the same size and surface gravity. These attributes brought myriad speculations about the nature of Venus, its climate, and the possibility of life existing there in some form. Mars also harbored interest as a place where life had or might still exist. Seasonal changes on Mars were interpreted as due to the possible spread and retreat of ice caps and lichen-like vegetation. A core element of this belief rested with the climatology of these two planets, as observed by astronomers, but these ideas were significantly altered, if not dashed during the space age. Missions to Venus and Mars revealed strikingly different worlds. The high temperatures and pressures found on Venus supported a "runaway greenhouse theory," and Mars harbored an apparently lifeless landscape similar to the surface of the Moon. While hopes for Venus as an abode of life ended, the search for evidence of past life on Mars, possibly microbial, remains a central theme in space exploration. This survey explores the evolution of thinking about the climates of Venus and Mars as life-support systems, in comparison to Earth.

  14. Venus-Earth-Mars: Comparative Climatology and the Search for Life in the Solar System

    Directory of Open Access Journals (Sweden)

    Roger D. Launius

    2012-09-01

    Full Text Available Both Venus and Mars have captured the human imagination during the twentieth century as possible abodes of life. Venus had long enchanted humans—all the more so after astronomers realized it was shrouded in a mysterious cloak of clouds permanently hiding the surface from view. It was also the closest planet to Earth, with nearly the same size and surface gravity. These attributes brought myriad speculations about the nature of Venus, its climate, and the possibility of life existing there in some form. Mars also harbored interest as a place where life had or might still exist. Seasonal changes on Mars were interpreted as due to the possible spread and retreat of ice caps and lichen-like vegetation. A core element of this belief rested with the climatology of these two planets, as observed by astronomers, but these ideas were significantly altered, if not dashed during the space age. Missions to Venus and Mars revealed strikingly different worlds. The high temperatures and pressures found on Venus supported a “runaway greenhouse theory,” and Mars harbored an apparently lifeless landscape similar to the surface of the Moon. While hopes for Venus as an abode of life ended, the search for evidence of past life on Mars, possibly microbial, remains a central theme in space exploration. This survey explores the evolution of thinking about the climates of Venus and Mars as life-support systems, in comparison to Earth.

  15. A Mars Riometer

    Science.gov (United States)

    Fry, C. D.; Rosenberg, T. J.; Lutz, L.; Detrick, D. L.; Weatherwax, A. T.; Knouse, E.; Breden, H.; Giganti, J.

    1998-09-01

    The Planetary Surface Instruments Workshop (Meyer et al., LPI Tech. Rpt. 95-05, 1995) identified surface-based radio science instruments as key tools for observing Mars' middle atmosphere, its ionosphere and solar-wind interaction. For example, Mars has a substantial daytime ionosphere, and some important features of the Martian ionosphere can only be observed from below. One instrument, the Relative Ionospheric Opacity Meter (Riometer), is expected to work well on Mars (Detrick et al., PSS, 45, p. 289, 1997). In the past, the size, power requirements and complexity of these instruments have argued against including them on a lander or rover mission, in spite of the potentially rich science return. We describe the development of a miniature radio receiver designed to operate as a Riometer. The development of this receiver was funded by NASA as an enabling technology for future planetary radio science missions. Our receiver includes features that are desirable for extended autonomous operation: low power consumption, wide dynamic range and linearity, computer command and data interface, and the ability to be remotely reconfigured. The receiver design provides significant improvements over previous implementations used in terrestrial riometry. The high degree of system linearity, combined with a digital feedback loop (including a low-duty calibration cycle), allows a longer measurement time. We were able to significantly miniaturize the receiver by using modern, low-power electronic components that have come on the market. We also implemented several of the subsystems in a field-programmable gate array, including the receiver detector, the control logic, and the data acquisition and processing blocks. Considerable efforts were made to eliminate or minimize RF noise and spurious emissions generated by the receiver's digital circuitry. Results of laboratory and field tests are presented and discussed.

  16. Un mar compartido

    OpenAIRE

    2008-01-01

    Existen pocos ámbitos más reveladores que el mar para entender las virtudes de la cooperación internacional en materia científica. En las ciencias marinas esta cooperación es más que deseable: es imprescindible para poder contestar preguntas relacionadas con el movimiento de las corrientes, el aporte de los ríos, los ciclos migratorios de las especies, las pesquerías, etc. Se analiza la importancia de los proyectos conjuntos donde participaron países latinoamericanos, algunos con éxitos, y so...

  17. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-08-25

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of SpecialApplications, in suppport of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. The report is a rearranged, updated, and significantly expanded amalgam of three interrelated papers presented at the 24th Intersocity Energy Conversion Engineering Conference (IECEC) at Arlington, Virginia, on August 10, 1989.

  18. The salts of Mars

    Science.gov (United States)

    Clark, B. C.; Van Hart, D. C.

    1981-01-01

    Salt compounds are apparently an important component of the fine-grained regolith on Mars. Salt enrichment may be explained either as a secondary concentration of chemical weathering products or as direct incorporation of planetary released volatiles. Geochemical measurements and chemical relationships constrain the salt species and resultant physicochemical consequences. A likely assemblage is dominated by (Mg,Na)SO4, NaCl, and (Mg,Ca)CO3. Formation of brine in equilibrium with such a salt mixture is unlikely under the temperature and water-vapor restrictions prevalent over most, if not all, of the Martian surface. Acidic conditions, accompanying salt formation, favor the preferential destruction of susceptible igneous minerals.

  19. Mars Surface Simulations

    Science.gov (United States)

    Nørnberg, Per; Merrison, Jonathan P.; Gunnlaugsson, Haraldur P.

    2010-05-01

    Laboratory simulations of the Martian surface are of importance to broaden scientific understanding of the physical processes, but also in order to develop the technology necessary for exploration of the planet. The Mars Simulation Laboratory at Aarhus University [1] has been involved in such simulations for around ten years and has developed several experimental facilities for carrying out science or instrument testing under conditions similar to those at the Martian surface, specifically low pressure, low temperature and importantly recreating the wind flow environment and dust suspension (reproducing the Martian dusty aerosol) using Mars analogue material [2]. The science involved in this simulation work has covered a broad spectrum including, erosion induced mineralogy/chemistry, particulate electrification, magnetic properties of Martian dust, biological survival, UV induced chemistry/mineralogy (using a solar simulator), adhesion/cohesion processes and the wind driven transport of dust and sand [3,4]. With regard to technology the wind tunnel facilities have been used in the development of the latest wind and dust sensing instrumentation [5,6]. With support from the European Space Agency (ESA) and Danish national funding an advanced Mars simulation facility has recently been constructed (2009). This wind tunnel facility has a cross section of 2 x 1 m and a length of 8 m, a temperature range down to below -120C, wind speeds in excess of 20m/s, and automated dust control. With a range of (specialised) sensing instrumentation it provides the opportunity to perform a new generation of scientific experiments and allow testing and technology development in the most realistic and rigorous environment. As well as being available for the space agencies, this facility will be open to all potential scientific collaborators. Also European planetary scientists may benefit from support through the EU Europlanet FP7 networking programme. For more information on access

  20. MARS15 overview

    Energy Technology Data Exchange (ETDEWEB)

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2007-01-01

    MARS15 is a Monte Carlo code for inclusive and exclusive simulation of three-dimensional hadronic and electromagnetic cascades, muon, heavy-ion, and low-energy neutron transport in accelerator, detector, spacecraft, and shielding components in the energy range from a fraction of an electronvolt up to 100 TeV. Main features of the code are described in this paper with a focus on recent developments and benchmarking. Newest developments concern inclusive and exclusive nuclear event generators, extended particle list in both modes, heavy-ion capability, electromagnetic interactions, enhanced geometry, tracking, histogramming and residual dose modules, improved graphical-user interface, and other external interfaces.

  1. Uncertainty of climates; L`incertitude des climats

    Energy Technology Data Exchange (ETDEWEB)

    Kandel, R. [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France)]|[Ecole Polytechnique, 75 - Paris (France)

    1998-11-01

    The climate is a fundamental aspect of our environment. It determines the life possibilities on our planet. The author takes stock of actual questions such: the greenhouse effect, the hole of the ozone layer, the deforestation of tropical forests, the warming of the planet, `El Nino`, by initiating us into climatology, this science that just have known a true technological revolution: climate modeling, paleoclimatology rise, development of observations by satellites. (N.C.)

  2. Xichang Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    Xichang Satellite Launch Center(XSLC) is mainly for geosynchronous orbit launches. The main purpose of XSLC is to launch spacecraft, such as broadcasting,communications and meteorological satellites, into geo-stationary orbit.Most of the commercial satellite launches of Long March vehicles have been from Xichang Satellite Launch Center. With 20 years' development,XSLC can launch 5 kinds of launch vehicles and send satellites into geostationary orbit and polar orbit. In the future, moon exploration satellites will also be launched from XSLC.

  3. Handbook of satellite applications

    CERN Document Server

    Madry, Scott; Camacho-Lara, Sergio

    2017-01-01

    The first edition of this ground breaking reference work was the most comprehensive reference source available about the key aspects of the satellite applications field. This updated second edition covers the technology, the markets, applications and regulations related to satellite telecommunications, broadcasting and networking—including civilian and military systems; precise satellite navigation and timing networks (i.e. GPS and others); remote sensing and meteorological satellite systems. Created under the auspices of the International Space University based in France, this brand new edition is now expanded to cover new innovative small satellite constellations, new commercial launching systems, innovation in military application satellites and their acquisition, updated appendices, a useful glossary and more.

  4. Life near the Roche limit - Behavior of ejecta from satellites close to planets

    Science.gov (United States)

    Dobrovolskis, A. R.; Burns, J. A.

    1980-01-01

    A study of the dynamics of nearby debris from impact craters was made to explain the distinctive features seen on Phobos, Deimis, and Amalthea. The planetary tides and satellite rotatio