Sample records for wisconsin ice age

  1. Exposure to Elevated Carbon Monoxide Levels at an Indoor Ice Arena--Wisconsin, 2014. (United States)

    Creswell, Paul D; Meiman, Jon G; Nehls-Lowe, Henry; Vogt, Christy; Wozniak, Ryan J; Werner, Mark A; Anderson, Henry


    On December 13, 2014, the emergency management system in Lake Delton, Wisconsin, was notified when a male hockey player aged 20 years lost consciousness after participation in an indoor hockey tournament that included approximately 50 hockey players and 100 other attendees. Elevated levels of carbon monoxide (CO) (range = 45 ppm-165 ppm) were detected by the fire department inside the arena. The emergency management system encouraged all players and attendees to seek medical evaluation for possible CO poisoning. The Wisconsin Department of Health Services (WDHS) conducted an epidemiologic investigation to determine what caused the exposure and to recommend preventive strategies. Investigators abstracted medical records from area emergency departments (EDs) for patients who sought care for CO exposure during December 13-14, 2014, conducted a follow-up survey of ED patients approximately 2 months after the event, and conducted informant interviews. Ninety-two persons sought ED evaluation for possible CO exposure, all of whom were tested for CO poisoning. Seventy-four (80%) patients had blood carboxyhemoglobin (COHb) levels consistent with CO poisoning; 32 (43%) CO poisoning cases were among hockey players. On December 15, the CO emissions from the propane-fueled ice resurfacer were demonstrated to be 4.8% of total emissions when actively resurfacing and 2.3% when idling, both above the optimal range of 0.5%-1.0%. Incomplete fuel combustion by the ice resurfacer was the most likely source of elevated CO. CO poisonings in ice arenas can be prevented through regular maintenance of ice resurfacers, installation of CO detectors, and provision of adequate ventilation.

  2. EASE-Grid Sea Ice Age (United States)

    National Aeronautics and Space Administration — This data set provides weekly estimates of sea ice age for the Arctic Ocean from remotely sensed sea ice motion and sea ice extent. The ice age data are derived from...

  3. Archive of Geosample Data and Information from the University of Wisconsin Ice Island T3 Core Collection (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — From 1963 to 1972, 349 piston cores were collected from the Arctic Ocean using Ice Island T3 as a sampling platform and sent to the University of Wisconsin-Madison...

  4. recurrent ice ages

    Directory of Open Access Journals (Sweden)

    Andrei Korobeinikov


    Full Text Available Rapid and dramatic changes in climate and glacial conditions have taken place during the last 2.5 million years of the earth's history. Huge ice sheets expanded and contracted periodically, at times covering large areas of North America and Europe. Global sea levels dropped and rose 100 m to 150 m in response to the growth and melting of glaciers, causing continental coast lines to move far into present sea areas and then retreated again. We will use a simple conceptual model to demonstrate that these climate and glacier fluctuations can be a consequence of a supercritical Hopf bifurcation in models of the “ocean-land-atmosphere” system.

  5. Ice Ages-Periodic Ice Coverings on the Earth

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 8. Ice Ages - Periodic Ice Coverings on the Earth. J Srinivasan. General Article Volume 4 Issue 8 August 1999 pp 25-35. Fulltext. Click here to view fulltext PDF. Permanent link: ...

  6. Ice age plant refugia in East Greenland

    DEFF Research Database (Denmark)

    Funder, Svend Visby


    From the distribution of plants it has been inferred by some botanists that ice-free areas existed in East Greenland accommodating a flora which survived one or several ice ages in the area. Comparing this evidence with recent information on the chronology of glaciations and post-glacial vegetati...

  7. Age-dependent changes in ecosystem carbon fluxes in managed forests in Northern Wisconsin, USA (United States)

    Asko Noormets; Jiquan Chen; Thomas R. Crow


    The age-dependent variability of ecosystem carbon (C) fluxes was assessed by measuring the net ecosystem exchange of C (NEE) in five managed forest stands in northern Wisconsin, USA. The study sites ranged in age from 3-year-old clearcut to mature stands (65 years). All stands, except the clearcut, accumulated C over the study period from May to October 2002. Seasonal...

  8. Ice age plant refugia in East Greenland

    DEFF Research Database (Denmark)

    Funder, Svend Visby


    From the distribution of plants it has been inferred by some botanists that ice-free areas existed in East Greenland accommodating a flora which survived one or several ice ages in the area. Comparing this evidence with recent information on the chronology of glaciations and post-glacial vegetation...... of Greenland. 14 C dating and amino-acid age estimates of marine sediments show that lowland areas near the outer coast have been ice-free for at least 40,000 years. The vegetation history, as reflected in pollen diagrams extending back to ca. 10,000 yr. B.P., has shown that many of the extant species...... immigrated from northern Europe and North America in post-glacial times. This contingency includes both some thermophilous species that were suggested as survivors by one group of botanists, and some extremely "hardy" species that were thought to have survived by another group. From the palynological...

  9. SKB/TVO ice age scenario

    International Nuclear Information System (INIS)

    Ahlbom, K.; Aeikaes, T.; Ericsson, L.


    Ice ages have repeatedly occurred throughout geological history, and it is likely that they will also occur in the future. The report discusses the principal processes predicted to occur during future glaciations, and which are likely to be of importance for a repository. The report presents a synthesis of the results in a form of a scenario from two state-of-the-art reports, working meetings and a seminar. Based on the present status of knowledge the climate at Scandinavia will gradually become colder permitting the growth of an ice sheet at 5000 years in the mountainous area of Sweden. After a minor warmer period fully stadial conditions will occur around 20 000 years from now, and after interstadial with dry and cold climate again after 60000 years from now. During the latter glaciation ice thickness at Stockholm-Helsinki region is 2500 m. Interstadial conditions similar to the climate of northern Sweden/Finland will prevail after 75000 years from now. The main changes caused by ice sheet are the downwarping/uplift of the crust and changes in the sea level. In addition, changes in groundwater head and flux are foreseen. As a response from climatic changes tundra and permafrost will appear

  10. Height growth to age 8 of larch species and hybrids in Wisconsin. (United States)

    Don E. Riemenschneider; Hans Nienstaedt


    Height growth of tamarack; Siberian, European and Japanese larch; and hybrids between the European and Japanese larch were compared in an 8-year-old test in north-central Wisconsin. Hybrids were tallest and best reached 469 cm (15.4 feet) in mean height at age 8 years from seed. Hybrids exceeded European larch mean height by 12% and tamarack by 23%. Breeding...

  11. SKB/TVO ice age scenario

    International Nuclear Information System (INIS)

    Ahlbom, K.; Aeikaes, T.; Ericsson, L.O.


    Ice ages have repeatedly occurred throughout geological history, and it is likely that they will also occur in the time-span considered for the disposal of nuclear fuel. Based on the present status of knowledge, this report discusses when future ice ages will occur and the possible changes in the geosphere that might be of importance for repository performance. The report is intended to be used as a basis when developing scenarios for safety analysis of final repository for spent nuclear fuel. Both the ACLIN and Imbrie and Imbrie models suggest stadials (glaciations) at c. 20000, 60000 and 100000 years from now. The ACLIN model also suggests a glaciation period around 5000 years ahead. The next interglacial period will occur at c. 75000 years, according to the Imbrie and Imbrie model, while the ACLIN model suggests that interglacial conditions will not appear until 125000 years form now. Other models strongly support the 60000 year glaciation event. To some extent there is also support for the 20000 and 5000 year events. For the purpose of the SKB/TVO scenario it is suggested that smaller or large glaciations will occur at 5000, 20000 and 60000 years form now. Following the last glaciation, interglacial conditions will prevail at 75000 years. Thus after the first glaciation (5000 years) this is the earliest time when most part of Sweden and Finland will once again be resettled by man. (25 refs.)

  12. IceAge: Chemical Evolution of Ices during Star Formation (United States)

    McClure, Melissa; Bailey, J.; Beck, T.; Boogert, A.; Brown, W.; Caselli, P.; Chiar, J.; Egami, E.; Fraser, H.; Garrod, R.; Gordon, K.; Ioppolo, S.; Jimenez-Serra, I.; Jorgensen, J.; Kristensen, L.; Linnartz, H.; McCoustra, M.; Murillo, N.; Noble, J.; Oberg, K.; Palumbo, M.; Pendleton, Y.; Pontoppidan, K.; Van Dishoeck, E.; Viti, S.


    Icy grain mantles are the main reservoir for volatile elements in star-forming regions across the Universe, as well as the formation site of pre-biotic complex organic molecules (COMs) seen in our Solar System. We propose to trace the evolution of pristine and complex ice chemistry in a representative low-mass star-forming region through observations of a: pre-stellar core, Class 0 protostar, Class I protostar, and protoplanetary disk. Comparing high spectral resolution (R 1500-3000) and sensitivity (S/N 100-300) observations from 3 to 15 um to template spectra, we will map the spatial distribution of ices down to 20-50 AU in these targets to identify when, and at what visual extinction, the formation of each ice species begins. Such high-resolution spectra will allow us to search for new COMs, as well as distinguish between different ice morphologies,thermal histories, and mixing environments. The analysis of these data will result in science products beneficial to Cycle 2 proposers. A newly updated public laboratory ice database will provide feature identifications for all of the expected ices, while a chemical model fit to the observed ice abundances will be released publically as a grid, with varied metallicity and UV fields to simulate other environments. We will create improved algorithms to extract NIRCAM WFSS spectra in crowded fields with extended sources as well as optimize the defringing of MIRI LRS spectra in order to recover broad spectral features. We anticipate that these resources will be particularly useful for astrochemistry and spectroscopy of fainter, extended targets like star forming regions of the SMC/LMC or more distant galaxies.

  13. On the origin of the ice ages

    NARCIS (Netherlands)

    Oerlemans, J.


    Ice sheet dynamics provide a possible explanation for the 100 kyr power in climatic records. Some numerical experiments presented here show that even the transition from an essentially ice-free earth to a glacial can be produced by a northern hemisphere ice-sheet model, provided that a

  14. On the origin of the ice ages


    Oerlemans, J.


    Ice sheet dynamics provide a possible explanation for the 100 kyr power in climatic records. Some numerical experiments presented here show that even the transition from an essentially ice-free earth to a glacial can be produced by a northern hemisphere ice-sheet model, provided that a slow general cooling on the northern hemisphere continents is imposed. Such a cooling could for example be the result of continental drift.

  15. Radiostratigraphy and age structure of the Greenland Ice Sheet. (United States)

    MacGregor, Joseph A; Fahnestock, Mark A; Catania, Ginny A; Paden, John D; Prasad Gogineni, S; Young, S Keith; Rybarski, Susan C; Mabrey, Alexandria N; Wagman, Benjamin M; Morlighem, Mathieu


    Several decades of ice-penetrating radar surveys of the Greenland and Antarctic ice sheets have observed numerous widespread internal reflections. Analysis of this radiostratigraphy has produced valuable insights into ice sheet dynamics and motivates additional mapping of these reflections. Here we present a comprehensive deep radiostratigraphy of the Greenland Ice Sheet from airborne deep ice-penetrating radar data collected over Greenland by The University of Kansas between 1993 and 2013. To map this radiostratigraphy efficiently, we developed new techniques for predicting reflection slope from the phase recorded by coherent radars. When integrated along track, these slope fields predict the radiostratigraphy and simplify semiautomatic reflection tracing. Core-intersecting reflections were dated using synchronized depth-age relationships for six deep ice cores. Additional reflections were dated by matching reflections between transects and by extending reflection-inferred depth-age relationships using the local effective vertical strain rate. The oldest reflections, dating to the Eemian period, are found mostly in the northern part of the ice sheet. Within the onset regions of several fast-flowing outlet glaciers and ice streams, reflections typically do not conform to the bed topography. Disrupted radiostratigraphy is also observed in a region north of the Northeast Greenland Ice Stream that is not presently flowing rapidly. Dated reflections are used to generate a gridded age volume for most of the ice sheet and also to determine the depths of key climate transitions that were not observed directly. This radiostratigraphy provides a new constraint on the dynamics and history of the Greenland Ice Sheet. Phase information predicts reflection slope and simplifies reflection tracingReflections can be dated away from ice cores using a simple ice flow modelRadiostratigraphy is often disrupted near the onset of fast ice flow.

  16. Carbon-14 ages of Allan Hills meteorites and ice (United States)

    Fireman, E. L.; Norris, T.


    Allan Hills is a blue ice region of approximately 100 sq km area in Antarctica where many meteorites have been found exposed on the ice. The terrestrial ages of the Allan Hills meteorites, which are obtained from their cosmogenic nuclide abundances are important time markers which can reflect the history of ice movement to the site. The principal purpose in studying the terrestrial ages of ALHA meteorites is to locate samples of ancient ice and analyze their trapped gas contents. Attention is given to the C-14 and Ar-39 terrestrial ages of ALHA meteorites, and C-14 ages and trapped gas compositions in ice samples. On the basis of the obtained C-14 terrestrial ages, and Cl-36 and Al-26 results reported by others, it is concluded that most ALHA meteorites fell between 20,000 and 200,000 years ago.

  17. Exposure age and ice-sheet model constraints on Pliocene East Antarctic ice sheet dynamics. (United States)

    Yamane, Masako; Yokoyama, Yusuke; Abe-Ouchi, Ayako; Obrochta, Stephen; Saito, Fuyuki; Moriwaki, Kiichi; Matsuzaki, Hiroyuki


    The Late Pliocene epoch is a potential analogue for future climate in a warming world. Here we reconstruct Plio-Pleistocene East Antarctic Ice Sheet (EAIS) variability using cosmogenic nuclide exposure ages and model simulations to better understand ice sheet behaviour under such warm conditions. New and previously published exposure ages indicate interior-thickening during the Pliocene. An ice sheet model with mid-Pliocene boundary conditions also results in interior thickening and suggests that both the Wilkes Subglacial and Aurora Basins largely melted, offsetting increased ice volume. Considering contributions from West Antarctica and Greenland, this is consistent with the most recent IPCC AR5 estimate, which indicates that the Pliocene sea level likely did not exceed +20 m on Milankovitch timescales. The inception of colder climate since ∼3 Myr has increased the sea ice cover and inhibited active moisture transport to Antarctica, resulting in reduced ice sheet thickness, at least in coastal areas.

  18. The genetic history of Ice Age Europe (United States)

    Fu, Qiaomei; Posth, Cosimo; Hajdinjak, Mateja; Petr, Martin; Mallick, Swapan; Fernandes, Daniel; Furtwängler, Anja; Haak, Wolfgang; Meyer, Matthias; Mittnik, Alissa; Nickel, Birgit; Peltzer, Alexander; Rohland, Nadin; Slon, Viviane; Talamo, Sahra; Lazaridis, Iosif; Lipson, Mark; Mathieson, Iain; Schiffels, Stephan; Skoglund, Pontus; Derevianko, Anatoly P.; Drozdov, Nikolai; Slavinsky, Vyacheslav; Tsybankov, Alexander; Cremonesi, Renata Grifoni; Mallegni, Francesco; Gély, Bernard; Vacca, Eligio; González Morales, Manuel R.; Straus, Lawrence G.; Neugebauer-Maresch, Christine; Teschler-Nicola, Maria; Constantin, Silviu; Moldovan, Oana Teodora; Benazzi, Stefano; Peresani, Marco; Coppola, Donato; Lari, Martina; Ricci, Stefano; Ronchitelli, Annamaria; Valentin, Frédérique; Thevenet, Corinne; Wehrberger, Kurt; Grigorescu, Dan; Rougier, Hélène; Crevecoeur, Isabelle; Flas, Damien; Semal, Patrick; Mannino, Marcello A.; Cupillard, Christophe; Bocherens, Hervé; Conard, Nicholas J.; Harvati, Katerina; Moiseyev, Vyacheslav; Drucker, Dorothée G.; Svoboda, Jiří; Richards, Michael P.; Caramelli, David; Pinhasi, Ron; Kelso, Janet; Patterson, Nick; Krause, Johannes; Pääbo, Svante; Reich, David


    Modern humans arrived in Europe ~45,000 years ago, but little is known about their genetic composition before the start of farming ~8,500 years ago. We analyze genome-wide data from 51 Eurasians from ~45,000-7,000 years ago. Over this time, the proportion of Neanderthal DNA decreased from 3–6% to around 2%, consistent with natural selection against Neanderthal variants in modern humans. Whereas the earliest modern humans in Europe did not contribute substantially to present-day Europeans, all individuals between ~37,000 and ~14,000 years ago descended from a single founder population which forms part of the ancestry of present-day Europeans. A ~35,000 year old individual from northwest Europe represents an early branch of this founder population which was then displaced across a broad region, before reappearing in southwest Europe during the Ice Age ~19,000 years ago. During the major warming period after ~14,000 years ago, a new genetic component related to present-day Near Easterners appears in Europe. These results document how population turnover and migration have been recurring themes of European pre-history. PMID:27135931

  19. A Method to Teach Age-Specific Demography with Field Grown Rapid Cycling "Brassica rapa" (Wisconsin Fast Plants) (United States)

    Kelly, Martin G.; Terrana, Sebastian


    In this paper, we demonstrate that rapid cycling "Brassica rapa" (Wisconsin Fast Plants) can be used in inquiry-based, student ecological fieldwork. We are the first to describe age-specific survival for field-grown Fast Plants and identify life history traits associated with individual survival. This experiment can be adapted by educators as a…


    Directory of Open Access Journals (Sweden)

    Anastasia Gornostayeva


    Full Text Available We applied geothermal method for paleoclimatic reconstruction of the ground surface temperature history during the Little Ice Age and contemporary warming. We analyzed 83 borehole temperature profiles and estimated warming amplitudes and warming start dates after the Little Ice Age. The studied boreholes are situated in the Urals and Eastern Europe (Finland, Ukraine, and Belarus. Our investigation shows high degree of spatial variability of climatic changes in 18–19 centuries. Spatial distribution of amplitudes of paleoclimatic changes and warming start date testifies that warming following after the Little Ice Age was in progress in several steps and for different regions it started at different times.

  1. Siple Dome ice reveals two modes of millennial CO2 change during the last ice age (United States)

    Ahn, Jinho; Brook, Edward J.


    Reconstruction of atmospheric CO2 during times of past abrupt climate change may help us better understand climate-carbon cycle feedbacks. Previous ice core studies reveal simultaneous increases in atmospheric CO2 and Antarctic temperature during times when Greenland and the northern hemisphere experienced very long, cold stadial conditions during the last ice age. Whether this relationship extends to all of the numerous stadial events in the Greenland ice core record has not been clear. Here we present a high-resolution record of atmospheric CO2 from the Siple Dome ice core, Antarctica for part of the last ice age. We find that CO2 does not significantly change during the short Greenlandic stadial events, implying that the climate system perturbation that produced the short stadials was not strong enough to substantially alter the carbon cycle. PMID:24781344

  2. Evolution of the early Antarctic ice ages

    NARCIS (Netherlands)

    Liebrand, Diederik; de Bakker, Anouk T M|info:eu-repo/dai/nl/371573734; Beddow, Helen M; Wilson, Paul A; Bohaty, Steven M; Ruessink, Gerben|info:eu-repo/dai/nl/169093360; Pälike, Heiko; Batenburg, Sietske J; Hilgen, Frederik J|info:eu-repo/dai/nl/102639876; Hodell, David A; Huck, Claire E; Kroon, Dick; Raffi, Isabella; Saes, Mischa J M; van Dijk, Arnold E|info:eu-repo/dai/nl/341412082; Lourens, Lucas J|info:eu-repo/dai/nl/125023103


    Understanding the stability of the early Antarctic ice cap in the geological past is of societal interest because present-day atmospheric CO2 concentrations have reached values comparable to those estimated for the Oligocene and the Early Miocene epochs. Here we analyze a new high-resolution

  3. On the world's ice ages and changing environments

    International Nuclear Information System (INIS)

    Eronen, M.; Olander, H.


    All known ice ages during the earth's history are reviewed. The oldest glaciation occurred around 2.3 billion years ago, followed by a series of large glaciations 950-650, 450-430 and 310-270 million years ago. Continental drift played a major role in these long-term climatic changes. The present Quaternary ice age actually began 17 million years ago, when a large ice mass grew over Antarctica. A detailed account is given of the climatic fluctuations during the Quaternary period (over 2.5 million years). Different stratigraphic records, and the relationship of climatic variations to orbital forcing are discussed. Large environmental changes took place in the course of the climate oscillations. Large ice sheets waxed and waned, global sea-levels fluctuated, forests disappeared from many regions during cold times and advanced during favourable times. The ice masses depressed the earth's crust markedly, and this then rose rapidly when the ice melted. The extent of glacial erosion is also discussed. Finally the postglacial climatic history of the earth is described and the consequences of the possible greenhouse effect are considered.(orig.)

  4. An ice age recorded in the polar deposits of Mars (United States)

    Smith, Isaac B.; Putzig, Nathaniel E.; Holt, John W.; Phillips, Roger J.


    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.

  5. New constraints on the gas age-ice age difference along the EPICA ice cores, 0–50 kyr

    Directory of Open Access Journals (Sweden)

    J. Chappellaz


    Full Text Available Gas is trapped in polar ice sheets at ~50–120 m below the surface and is therefore younger than the surrounding ice. Firn densification models are used to evaluate this ice age-gas age difference (Δage in the past. However, such models need to be validated by data, in particular for periods colder than present day on the East Antarctic plateau. Here we bring new constraints to test a firn densification model applied to the EPICA Dome C (EDC site for the last 50 kyr, by linking the EDC ice core to the EPICA Dronning Maud Land (EDML ice core, both in the ice phase (using volcanic horizons and in the gas phase (using rapid methane variations. We also use the structured 10Be peak, occurring 41 kyr before present (BP and due to the low geomagnetic field associated with the Laschamp event, to experimentally estimate the Δage during this event. Our results seem to reveal an overestimate of the Δage by the firn densification model during the last glacial period at EDC. Tests with different accumulation rates and temperature scenarios do not entirely resolve this discrepancy. Although the exact reasons for the Δage overestimate at the two EPICA sites remain unknown at this stage, we conclude that current densification model simulations have deficits under glacial climatic conditions. Whatever the cause of the Δage overestimate, our finding suggests that the phase relationship between CO2 and EDC temperature previously inferred for the start of the last deglaciation (lag of CO2 by 800±600 yr seems to be overestimated.

  6. Ice-age megafauna in Arctic Alaska: extinction, invasion, survival (United States)

    Mann, Daniel H.; Groves, Pamela; Kunz, Michael L.; Reanier, Richard E.; Gaglioti, Benjamin V.


    Radical restructuring of the terrestrial, large mammal fauna living in arctic Alaska occurred between 14,000 and 10,000 years ago at the end of the last ice age. Steppe bison, horse, and woolly mammoth became extinct, moose and humans invaded, while muskox and caribou persisted. The ice age megafauna was more diverse in species and possibly contained 6× more individual animals than live in the region today. Megafaunal biomass during the last ice age may have been 30× greater than present. Horse was the dominant species in terms of number of individuals. Lions, short-faced bears, wolves, and possibly grizzly bears comprised the predator/scavenger guild. The youngest mammoth so far discovered lived ca 13,800 years ago, while horses and bison persisted on the North Slope until at least 12,500 years ago during the Younger Dryas cold interval. The first people arrived on the North Slope ca 13,500 years ago. Bone-isotope measurements and foot-loading characteristics suggest megafaunal niches were segregated along a moisture gradient, with the surviving species (muskox and caribou) utilizing the warmer and moister portions of the vegetation mosaic. As the ice age ended, the moisture gradient shifted and eliminated habitats utilized by the dryland, grazing species (bison, horse, mammoth). The proximate cause for this change was regional paludification, the spread of organic soil horizons and peat. End-Pleistocene extinctions in arctic Alaska represent local, not global extinctions since the megafaunal species lost there persisted to later times elsewhere. Hunting seems unlikely as the cause of these extinctions, but it cannot be ruled out as the final blow to megafaunal populations that were already functionally extinct by the time humans arrived in the region.


    Directory of Open Access Journals (Sweden)



    Full Text Available This study presents a review about the uses of Wisconsin Card Sorting Test in psychiatry disorders, attention deficit hyperactivity disorder, autism and aging. We searched more than 50 articles in MEDLINE, ProQuest and EBSCO databases from 1995 to 2005. 47 articles were selected and reported. The test was included in 61.7% of the studies related to assessment in attention deficit hyperactivity disorder, 19.5% in psychiatry disorders, 10.63% in autism, and 8.51% in aging. 100% of the articles showed quantitative analyses, 12.77% exposed variations in the application of the test (number of cards or virtual sceneries applications. Our findings suggest the needed to complement the quantitative analyses with qualitative analyses.

  8. Ice age aerosol content from east Antarctic ice core samples and past wind strength

    International Nuclear Information System (INIS)

    Petit, J.R.; Briat, M.; Royer, A.


    The possible link between the aerosol content from the 905 deep Dome C ice core (East Antartica) which spans some 32,000 yr (Lorius et al. Nature; 280:644 (1979)) and climate, is considered. No evidence of major global or local volcanic activity was found though large marine and continental inputs (respectively 5 and 20 times higher than present) were observed at the end of the last Glacial stage. It is considered that they reflect glacial age climate with stronger atmospheric circulation, enhanced aridity and faster aerosol transport towards the Antarctic continent. (U.K.)

  9. IceCube Polar Virtual Reality exhibit: immersive learning for learners of all ages (United States)

    Madsen, J.; Bravo Gallart, S.; Chase, A.; Dougherty, P.; Gagnon, D.; Pronto, K.; Rush, M.; Tredinnick, R.


    The IceCube Polar Virtual Reality project is an innovative, interactive exhibit that explains the operation and science of a flagship experiment in polar research, the IceCube Neutrino Observatory. The exhibit allows users to travel from the South Pole, where the detector is located, to the furthest reaches of the universe, learning how the detection of high-energy neutrinos has opened a new view to the universe. This novel exhibit combines a multitouch tabletop display system and commercially available virtual reality (VR) head-mounted displays to enable informal STEM learning of polar research. The exhibit, launched in early November 2017 during the Wisconsin Science Festival in Madison, WI, will study how immersive VR can enhance informal STEM learning. The foundation of this project is built upon a strong collaborative effort between the Living Environments Laboratory (LEL), the Wisconsin IceCube Particle Astrophysics Center (WIPAC), and the Field Day Laboratory groups from the University of Wisconsin-Madison campus. The project is funded through an NSF Advancing Informal STEM Learning (AISL) grant, under a special call for engaging students and the public in polar research. This exploratory pathways project seeks to build expertise to allow future extensions. The plan is to submit a subsequent AISL Broad Implementation proposal to add more 3D environments for other Antarctic research topics and locations in the future. We will describe the current implementation of the project and discuss the challenges and opportunities of working with an interdisciplinary team of scientists and technology and education researchers. We will also present preliminary assessment results, which seek to answer questions such as: Did users gain a better understanding of IceCube research from interacting with the exhibit? Do both technologies (touch table and VR headset) provide the same level of engagement? Is one technology better suited for specific learning outcomes?

  10. Acting Out History from the Ice Age to the Modern Age. (United States)

    Mattioli, Denee J.; Drake, Frederick


    Addresses the teaching methods of Michael Welch, a seventh grade teacher, who incorporates the humanities, such as drama and literature, into his history classroom in order to help students learn to question, think analytically, solve problems, and make decisions. Summarizes a particular unit on the Ice Age. (CMK)

  11. Mass loss of the Greenland Ice Sheet since the Little Ice Age, implications on sea level

    DEFF Research Database (Denmark)

    Kjeldsen, K. K.; Bjork, A. A.; Khan, Shfaqat Abbas

    The impact of mass loss from the Greenland Ice Sheet (GrIS) on 20th Century sea level rise (SLR) has long been subject to intense discussions. While globally distributed tide gauges suggest a global mean SLR of 15-20 cm, quantifying the separate components is of great concern - in particular......) and end moraines marking the ice extent of the LIA, which thereby enables us to obtain vertical point-based differences associated with changes in ice extent. These point measurements are combined with contemporary ice surface differences derived using NASA's Airborne Topographic Mapper (ATM) from 2002...

  12. Effect of photochemical ageing on the ice nucleation properties of diesel and wood burning particles

    Directory of Open Access Journals (Sweden)

    C. Chou


    Full Text Available A measurement campaign (IMBALANCE conducted in 2009 was aimed at characterizing the physical and chemical properties of freshly emitted and photochemically aged combustion particles emitted from a log wood burner and diesel vehicles: a EURO3 Opel Astra with a diesel oxidation catalyst (DOC but no particle filter and a EURO2 Volkswagen Transporter TDI Syncro without emission aftertreatment. Ice nucleation experiments in the deposition and condensation freezing modes were conducted with the Portable Ice Nucleation Chamber (PINC at three nominal temperatures, −30 °C, −35 °C and −40 °C. Freshly emitted diesel particles showed ice formation only at −40 °C in the deposition mode at 137% relative humidity with respect to ice (RHi and 92% relative humidity with respect to water (RHw, and photochemical ageing did not play a role in modifying their ice nucleation behaviour. Only one diesel experiment where α-pinene was added for the ageing process, showed an ice nucleation enhancement at −35 °C. Wood burning particles also act as ice nuclei (IN at −40 °C in the deposition mode at the same conditions as for diesel particles and photochemical ageing also did not alter the ice formation properties of the wood burning particles. Unlike diesel particles, wood burning particles form ice via condensation freezing at −35 °C whereas no ice nucleation was observed at −30 °C. Photochemical ageing did not affect the ice nucleation ability of the diesel and wood burning particles at the three different temperatures investigated but a broader range of temperatures below −40 °C need to be investigated in order to draw an overall conclusion on the effect of photochemical ageing on deposition/condensation ice nucleation across the entire temperature range relevant to cold clouds.

  13. 75 FR 18828 - Wisconsin Electric Power Company, Wisconsin Gas LLC, Wisconsin Public Service Corporation... (United States)


    ... Energy Regulatory Commission Wisconsin Electric Power Company, Wisconsin Gas LLC, Wisconsin Public Service Corporation: Complainants; ANR Pipeline Company: Respondent; Notice of Complaint April 6, 2010....206 (2009), Wisconsin Electric Power Company, Wisconsin Gas LLC, and Wisconsin Public Service...

  14. Siple Dome Ice Core Age-Depth Scales, Version 1 (United States)

    National Aeronautics and Space Administration — This data set is part of the WAISCORES project, an NSF-funded project to understand the influence of the West Antarctic ice sheet on climate and sea level change....

  15. Ages, ablation and accumulation rates from 14C measurements on Antarctic ice

    NARCIS (Netherlands)

    Roijen, J.J. van; Borg, K. van der; Jong, A.F.M. de; Oerlemans, J.


    Shallow ice cores from an Antarctic blue-ice area at Scharllenbergbotncn were 14C-analyzed using a dry-extraction technique and accelerator mass spectrometry. The in situ production was determined from the 14CO component and used to deduce the natural 14CO2 component. The ages were measured

  16. Age of Allan Hills 82102, a meteorite found inside the ice (United States)

    Nishiizumi, K.; Jull, A. J. T.; Bonani, G.; Suter, M.; Woelfli, W.


    The terrestrial age of a meteorite that was recovered from below the surface of Antarctic ice is reported, and it is argued that this represents a measurement of the age of the ice itself. The cosmogenic radionuclides Be-10, C-14, Al-26, Cl-36, and Mn-53 are measured in the meteorite and Be-10 and Cl-36 in the ice. A terrestrial age of 11,000 yr is obtained for the meteorite, which suggests that the snow accumulation area where it fell was only a few tens of km away.

  17. Ice ages and the thermal equilibrium of the earth, II (United States)

    Adam, D.P.


    The energy required to sustain midlatitude continental glaciations comes from solar radiation absorbed by the oceans. It is made available through changes in relative amounts of energy lost from the sea surface as net outgoing infrared radiation, sensible heat loss, and latent heat loss. Ice sheets form in response to the initial occurrence of a large perennial snowfield in the subarctic. When such a snowfield forms, it undergoes a drastic reduction in absorbed solar energy because of its high albedo. When the absorbed solar energy cannot supply local infrared radiation losses, the snowfield cools, thus increasing the energy gradient between itself and external, warmer areas that can act as energy sources. Cooling of the snowfield progresses until the energy gradients between the snowfield and external heat sources are sufficient to bring in enough (latent plus sensible) energy to balance the energy budget over the snowfield. Much of the energy is imported as latent heat. The snow that falls and nourishes the ice sheet is a by-product of the process used to satisfy the energy balance requirements of the snowfield. The oceans are the primary energy source for the ice sheet because only the ocean can supply large amounts of latent heat. At first, some of the energy extracted by the ice sheet from the ocean is stored heat, so the ocean cools. As it cools, less energy is lost as net outgoing infrared radiation, and the energy thus saved is then available to augment evaporation. The ratio between sensible and latent heat lost by the ocean is the Bowen ratio; it depends in part on the sea surface temperature. As the sea surface temperature falls during a glaciation, the Bowen ratio increases, until most of the available energy leaves the oceans as sensible, rather than latent heat. The ice sheet starves, and an interglacial period begins. The oscillations between stadial and interstadial intervals within a glaciation are caused by the effects of varying amounts of

  18. Uranium isotopes and dissolved organic carbon in loess permafrost: Modeling the age of ancient ice (United States)

    Ewing, Stephanie A.; Paces, James B.; O'Donnell, J.A.; Jorgenson, M.T.; Kanevskiy, M.Z.; Aiken, George R.; Shur, Y.; Harden, Jennifer W.; Striegl, Robert G.


    The residence time of ice in permafrost is an indicator of past climate history, and of the resilience and vulnerability of high-latitude ecosystems to global change. Development of geochemical indicators of ground-ice residence times in permafrost will advance understanding of the circumstances and evidence of permafrost formation, preservation, and thaw in response to climate warming and other disturbance. We used uranium isotopes to evaluate the residence time of segregated ground ice from ice-rich loess permafrost cores in central Alaska. Activity ratios of 234U vs. 238U (234U/238U) in water from thawed core sections ranged between 1.163 and 1.904 due to contact of ice and associated liquid water with mineral surfaces over time. Measured (234U/238U) values in ground ice showed an overall increase with depth in a series of five neighboring cores up to 21 m deep. This is consistent with increasing residence time of ice with depth as a result of accumulation of loess over time, as well as characteristic ice morphologies, high segregated ice content, and wedge ice, all of which support an interpretation of syngenetic permafrost formation associated with loess deposition. At the same time, stratigraphic evidence indicates some past sediment redistribution and possibly shallow thaw among cores, with local mixing of aged thaw waters. Using measures of surface area and a leaching experiment to determine U distribution, a geometric model of (234U/238U) evolution suggests mean ages of up to ∼200 ky BP in the deepest core, with estimated uncertainties of up to an order of magnitude. Evidence of secondary coatings on loess grains with elevated (234U/238U) values and U concentrations suggests that refinement of the geometric model to account for weathering processes is needed to reduce uncertainty. We suggest that in this area of deep ice-rich loess permafrost, ice bodies have been preserved from the last glacial period (10–100 ky BP), despite subsequent

  19. Causes of ice age intensification across the Mid-Pleistocene Transition (United States)

    Chalk, Thomas B.; Hain, Mathis P.; Foster, Gavin L.; Rohling, Eelco J.; Sexton, Philip F.; Badger, Marcus P. S.; Cherry, Soraya G.; Hasenfratz, Adam P.; Haug, Gerald H.; Jaccard, Samuel L.; Martínez-García, Alfredo; Pälike, Heiko; Pancost, Richard D.; Wilson, Paul A.


    During the Mid-Pleistocene Transition (MPT; 1,200–800 kya), Earth's orbitally paced ice age cycles intensified, lengthened from ˜40,000 (˜40 ky) to ˜100 ky, and became distinctly asymmetrical. Testing hypotheses that implicate changing atmospheric CO2 levels as a driver of the MPT has proven difficult with available observations. Here, we use orbitally resolved, boron isotope CO2 data to show that the glacial to interglacial CO2 difference increased from ˜43 to ˜75 μatm across the MPT, mainly because of lower glacial CO2 levels. Through carbon cycle modeling, we attribute this decline primarily to the initiation of substantive dust-borne iron fertilization of the Southern Ocean during peak glacial stages. We also observe a twofold steepening of the relationship between sea level and CO2-related climate forcing that is suggestive of a change in the dynamics that govern ice sheet stability, such as that expected from the removal of subglacial regolith or interhemispheric ice sheet phase-locking. We argue that neither ice sheet dynamics nor CO2 change in isolation can explain the MPT. Instead, we infer that the MPT was initiated by a change in ice sheet dynamics and that longer and deeper post-MPT ice ages were sustained by carbon cycle feedbacks related to dust fertilization of the Southern Ocean as a consequence of larger ice sheets.

  20. Challenging ICES age estimation protocols: lessons learned from the eastern Baltic cod stock

    DEFF Research Database (Denmark)

    Hüssy, Karin; Radtke, Krzysztof; Plikshs, Maris


    -validation is urgently needed. Deviations from the ICES guidelines identified are as follows: (i) the lack of rigorous quality control, particularly the auditing of national trends in age precision over the years using a reference collection and (ii) the implementation of an age error matrix in the stock assessment...

  1. County-Level Climate Uncertainty for Risk Assessments: Volume 24 Appendix W - Historical Sea Ice Age.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lowry, Thomas Stephen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Shannon M [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Barry L [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Malczynski, Leonard A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

  2. County-Level Climate Uncertainty for Risk Assessments: Volume 25 Appendix X - Forecast Sea Ice Age.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lowry, Thomas Stephen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Shannon M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Barry L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Malczynski, Leonard A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    This report uses the CMIP5 series of climate model simulations to produce country- level uncertainty distributions for use in socioeconomic risk assessments of climate change impacts. It provides appropriate probability distributions, by month, for 169 countries and autonomous-areas on temperature, precipitation, maximum temperature, maximum wind speed, humidity, runoff, soil moisture and evaporation for the historical period (1976-2005), and for decadal time periods to 2100. It also provides historical and future distributions for the Arctic region on ice concentration, ice thickness, age of ice, and ice ridging in 15-degree longitude arc segments from the Arctic Circle to 80 degrees latitude, plus two polar semicircular regions from 80 to 90 degrees latitude. The uncertainty is meant to describe the lack of knowledge rather than imprecision in the physical simulation because the emphasis is on unfalsified risk and its use to determine potential socioeconomic impacts. The full report is contained in 27 volumes.

  3. Foraminiferal faunal estimates of paleotemperature: Circumventing the no-analog problem yields cool ice age tropics (United States)

    Mix, A.C.; Morey, A.E.; Pisias, N.G.; Hostetler, S.W.


    The sensitivity of the tropics to climate change, particularly the amplitude of glacial-to-interglacial changes in sea surface temperature (SST), is one of the great controversies in paleoclimatology. Here we reassess faunal estimates of ice age SSTs, focusing on the problem of no-analog planktonic foraminiferal assemblages in the equatorial oceans that confounds both classical transfer function and modern analog methods. A new calibration strategy developed here, which uses past variability of species to define robust faunal assemblages, solves the no-analog problem and reveals ice age cooling of 5??to 6??C in the equatorial current systems of the Atlantic and eastern Pacific Oceans. Classical transfer functions underestimated temperature changes in some areas of the tropical oceans because core-top assemblages misrepresented the ice age faunal assemblages. Our finding is consistent with some geochemical estimates and model predictions of greater ice age cooling in the tropics than was inferred by Climate: Long-Range Investigation, Mapping, and Prediction (CLIMAP) [1981] and thus may help to resolve a long-standing controversy. Our new foraminiferal transfer function suggests that such cooling was limited to the equatorial current systems, however, and supports CLIMAP's inference of stability of the subtropical gyre centers.

  4. The late Cainozoic East Antarctic ice sheet

    International Nuclear Information System (INIS)

    Colhoun, E.A.


    A review, mainly of East Antarctic late Cainozoic (post 40 Ma) geological and geomorphological evidence, supports the hypothesis of the continuous presence of an ice sheet, of about the present size, since the late Miocene. Evidence is presented and the view advanced that, during the late Wisconsin maximum of isotope stage 2, ice was not nearly as thick or extensive over the continental shelf as required by the model of 'maximum' Antarctic glaciation. Some of the factors influencing the contribution of Antarctica to post-glacial sea-level rise are discussed. It is considered that Antarctica's contribution was probably considerably less than previously estimated. The dating of marine and freshwater sequences in the Vestfold and Bunger Hills is consistent with deglaciation around the Pleistocene Holocene boundary, after the Late Wisconsin maximum. A date of ∼25 ka BP from permafrost in the Larsemann Hills means that either the Larsemann Hills were not glaciated during the Late Wisconsin or the ice failed to erode much of the permafrost surface. The degree of weathering of rock and glacial drifts in the Vestfold, Larsemann and Bunger Hills suggests a long time for formation, perhaps considerably longer than indicated by the dated marine and freshwater sediment sequences. Cosmogenic isotope dating in the Vestfold Hills has provided equivocal ages for deglaciation. While the results could indicate deglaciation before 80 ka BP, they do not confirm such early deglaciation. If the ice cover was thin and failed to remove the previous rock exposure profile, then the assays could predate the last ice advance. Weathered iron crust fragments in the till suggest little erosion. The raised beaches of the oases are Holocene. Assuming they have been produced by post Late Wisconsin isostatic uplift and by the Holocene transgression, calculations show that the Antarctic continental ice sheet could not have been more than ∼500 m thicker in the inner shelf-coastal zone. The

  5. Addressing elderly mobility issues in Wisconsin. (United States)


    "The aging of baby boomers poses significant challenges to Wisconsins existing transportation infrastructure and specialized transit : programs. From 2010 to 2035, the number of elderly Wisconsinites is projected to grow by 90 percent, an increase...

  6. Morphological, Physiological and Skating Performance Profiles of Male Age-Group Elite Ice Hockey Players (United States)

    Allisse, Maxime; Sercia, Pierre; Comtois, Alain-Steve; Leone, Mario


    Abstract The purpose of this study was to describe the evolution of morphological, physiological and skating performance profiles of elite age-group ice hockey players based on repeated measures spread over one season. In addition, the results of fitness tests and training programs performed in off-ice conditions and their relationship with skating performance were analyzed. Eighteen high level age-group ice hockey players (13.1 ± 0.6 years) were assessed off and on-ice at the beginning and at the end of the hockey season. A third evaluation was also conducted at the beginning of the following hockey season. The players were taller, heavier, and showed bone breadths and muscle girths above the reference population of the same age. Muscular variables improved significantly during and between the two hockey seasons (p hockey season, but not during the off-season where some degradation was observed. Finally, weak observed variances (generally hockey players certainly deserves to be continued. PMID:28828080

  7. Brazilian preliminary norms and investigation of age and education effects on the Modified Wisconsin Card Sorting Test, Stroop Color and Word test and Digit Span test in adults. (United States)

    Zimmermann, Nicolle; Cardoso, Caroline de Oliveira; Trentini, Clarissa Marceli; Grassi-Oliveira, Rodrigo; Fonseca, Rochele Paz


    Executive functions are involved in a series of human neurological and psychiatric disorders. For this reason, appropriate assessment tools with age and education adjusted norms for symptom diagnosis are necessary. To present normative data for adults (19-75 year-olds; with five years of education or more) on the Modified Wisconsin Card Sorting Test (MWCST), Stroop color and word test and Digit Span test. Age and education effects were investigated. Three samples were formed after inclusion criteria and data analysis: MWCST (n=124); Digit Span (n=123), and Stroop test (n=158). Groups were divided into young (19-39), middle-aged (40-59) and older (60-75) participants with five to eight years of education and nine years of education or more. Two-way ANOVA and ANCOVA analyses were used. Education effects were found in most variables of the three tasks. An age effect was only found on color naming and color-word naming speed from the Stroop test. No interactions were detected. In countries with heterogeneous educational backgrounds, the use of stratified norms by education to assess at least some components of executive functions is essential for an ethical and accurate cognitive diagnosis.

  8. End of the "Little Ice Age" in the Alps not forced by industrial black carbon (United States)

    Sigl, Michael; Osmont, Dimtri; Gabrieli, Jacopo; Barbante, Carlo; Schwikowski, Margit


    Light absorbing aerosols present in the atmosphere and cryosphere play an important role in the climate system. Their presence in ambient air and snow changes radiative properties of these media, thus contributing to increased atmospheric warming and snowmelt. High spatio-temporal variability of aerosol concentrations in these media and a shortage of long-term observations contribute to large uncertainties in properly assigning the climate effects of these aerosols through time. Glaciers in the European Alps began to retreat abruptly from their mid-19th century maximum, marking what appeared to be the end of the Little Ice Age. Radiative forcing by increasing deposition of industrial black carbon to snow has been suggested as the main driver of the abrupt glacier retreats in the Alps (Painter et al. 2012). Basis for this hypothesis were model simulations using ice-core measurements of elemental carbon at low temporal resolution from two ice cores in the Alps. Here we present sub-annually resolved, well replicated ice-core measurements of refractory black carbon (rBC; using a SP2 soot photometer), mineral dust (Fe, Ca), biomass burning (NH4, K) and distinctive industrial pollution tracers (Bi, Pb, SO4) from an ice core in the Alps covering the past 250 years. These reconstructions allow to precisely compare the timing of observed acceleration of glacier melt in the mid-19th century with that of the increase of soot deposition on ice-sheets caused by the industrialization of Western Europe. Our study suggests that at the time when European rBC emission rates started to significantly increase Alpine glaciers have already experienced more than 70% of their total 19th century length reduction. Industrial BC emissions can therefore not been considered as the primary forcing of the rapid deglaciation at the end of the Little Ice Age in the Alps. References: Painter, T. H., M. G. Flanner, G. Kaser, B. Marzeion, R. A. VanCuren, and W. Abdalati (2013), End of the Little Ice

  9. Serum PCB profiles in Native Americans from Wisconsin based on region, diet, age, and gender: Implications for epidemiology studies

    International Nuclear Information System (INIS)

    Schaeffer, David J.; Dellinger, John A.; Needham, Larry L.; Hansen, Larry G.


    Background: Different PCB congeners and different mixtures of congeners have been demonstrated to have different biological actions. More complete characterization of congener profiles in exposure sources may assist in predicting health outcomes. Methods: Thirty-six (36) polychlorinated biphenyl (PCB) congeners were measured by gas chromatography isotope-dilution mass spectrometry (IDMS) in 314 serum samples from Native Americans in Wisconsin, Michigan and Minnesota. Five dietary groups were established based on the quantity and species of fish consumed and the waters from which the fish were caught. Multivariate statistical methods were able to resolve gender and dietary differences in PCB homologue and PCB congener patterns. Results: Females had higher proportions of lower chlorinated homologues, including a consistently higher proportion of pentaCB 118. The relative presence of the very labile and volatile PCB 18, above 1% of the total PCB in females from the minimal fish consumption and 'other' groups, suggests possible exposure to PCBs in the atmosphere. The dietary group consuming predatory fishes from Lakes Michigan and Superior had the highest serum concentrations of total PCB (mean of 3.1 ng/ml) and the most distinct congener profile. The two dietary groups least dependent on fishing or fishing mostly from inland lakes (non-Great Lakes) had the lowest total PCB concentrations, both with means of 1.4 ng/ml. Conclusions: These serum PCB concentrations were less than those found in earlier studies of fish consumers in the Great Lakes region and may reflect the decrease in PCBs in these lakes

  10. Life and extinction of megafauna in the ice-age Arctic. (United States)

    Mann, Daniel H; Groves, Pamela; Reanier, Richard E; Gaglioti, Benjamin V; Kunz, Michael L; Shapiro, Beth


    Understanding the population dynamics of megafauna that inhabited the mammoth steppe provides insights into the causes of extinctions during both the terminal Pleistocene and today. Our study area is Alaska's North Slope, a place where humans were rare when these extinctions occurred. After developing a statistical approach to remove the age artifacts caused by radiocarbon calibration from a large series of dated megafaunal bones, we compare the temporal patterns of bone abundance with climate records. Megafaunal abundance tracked ice age climate, peaking during transitions from cold to warm periods. These results suggest that a defining characteristic of the mammoth steppe was its temporal instability and imply that regional extinctions followed by population reestablishment from distant refugia were characteristic features of ice-age biogeography at high latitudes. It follows that long-distance dispersal was crucial for the long-term persistence of megafaunal species living in the Arctic. Such dispersal was only possible when their rapidly shifting range lands were geographically interconnected. The end of the last ice age was fatally unique because the geographic ranges of arctic megafauna became permanently fragmented after stable, interglacial climate engendered the spread of peatlands at the same time that rising sea level severed former dispersal routes.

  11. Life and extinction of megafauna in the ice-age Arctic (United States)

    Mann, Daniel H.; Groves, Pamela; Reanier, Richard E.; Gaglioti, Benjamin V.; Kunz, Michael L.; Shapiro, Beth


    Understanding the population dynamics of megafauna that inhabited the mammoth steppe provides insights into the causes of extinctions during both the terminal Pleistocene and today. Our study area is Alaska's North Slope, a place where humans were rare when these extinctions occurred. After developing a statistical approach to remove the age artifacts caused by radiocarbon calibration from a large series of dated megafaunal bones, we compare the temporal patterns of bone abundance with climate records. Megafaunal abundance tracked ice age climate, peaking during transitions from cold to warm periods. These results suggest that a defining characteristic of the mammoth steppe was its temporal instability and imply that regional extinctions followed by population reestablishment from distant refugia were characteristic features of ice-age biogeography at high latitudes. It follows that long-distance dispersal was crucial for the long-term persistence of megafaunal species living in the Arctic. Such dispersal was only possible when their rapidly shifting range lands were geographically interconnected. The end of the last ice age was fatally unique because the geographic ranges of arctic megafauna became permanently fragmented after stable, interglacial climate engendered the spread of peatlands at the same time that rising sea level severed former dispersal routes.

  12. Evidence for a little ice age and recent warming from a borehole temperature data inversion procedure

    International Nuclear Information System (INIS)

    Fivez, J.; Thoen, J.


    In this article, we apply our analytical theory, published earlier in this journal, to obtain information on the earth surface temperature history from some borehole temperature data. Compared to the results of the five different methods applied to the same temperature data, our method seems to be easier, assumption-free, and yields internally consistent results. The results suggest a cooling a few centuries ago, followed by a continuing warming up to these days, in agreement with a little ice age scenario

  13. Climate change threatens archaeologically significant ice patches: insights into their age, internal structure, mass balance and climate sensitivity (United States)

    Strand Ødegård, Rune; Nesje, Atle; Isaksen, Ketil; Andreassen, Liss Marie; Eiken, Trond; Schwikowski, Margit; Uglietti, Chiara


    Despite numerous spectacular archaeological discoveries worldwide related to melting ice patches and the emerging field of glacial archaeology, governing processes related to ice patch development during the Holocene and their sensitivity to climate change are still largely unexplored. Here we present new results from an extensive 6-year (2009-2015) field experiment at the Juvfonne ice patch in Jotunheimen in central southern Norway. Our results show that the ice patch has existed continuously since the late Mesolithic period. Organic-rich layers and carbonaceous aerosols embedded in clear ice show ages spanning from modern at the surface to ca. 7600 cal years BP at the bottom. This is the oldest dating of ice in mainland Norway. The expanding ice patch covered moss mats appearing along the margin of Juvfonne about 2000 years ago. During the study period, the mass balance record showed a strong negative balance, and the annual balance is highly asymmetric over short distances. Snow accumulation is poorly correlated with estimated winter precipitation, and single storm events may contribute significantly to the total winter balance. Snow accumulation is approx. 20% higher in the frontal area compared to the upper central part of the ice patch. There is sufficient meltwater to bring the permeable snowpack to an isothermal state within a few weeks in early summer. Below the seasonal snowpack, ice temperatures are between -2 and -4 °C. Juvfonne has clear ice stratification of isochronic origin. Reference: The Cryosphere, 11, 17-32, 2017.

  14. Modulation of ice ages via precession and dust-albedo feedbacks

    Directory of Open Access Journals (Sweden)

    Ralph Ellis


    Full Text Available We present here a simple and novel proposal for the modulation and rhythm of ice-ages and interglacials during the late Pleistocene. While the standard Milankovitch-precession theory fails to explain the long intervals between interglacials, these can be accounted for by a novel forcing and feedback system involving CO2, dust and albedo. During the glacial period, the high albedo of the northern ice sheets drives down global temperatures and CO2 concentrations, despite subsequent precessional forcing maxima. Over the following millennia more CO2 is sequestered in the oceans and atmospheric concentrations eventually reach a critical minima of about 200 ppm, which combined with arid conditions, causes a die-back of temperate and boreal forests and grasslands, especially at high altitude. The ensuing soil erosion generates dust storms, resulting in increased dust deposition and lower albedo on the northern ice sheets. As northern hemisphere insolation increases during the next Milankovitch cycle, the dust-laden ice-sheets absorb considerably more insolation and undergo rapid melting, which forces the climate into an interglacial period. The proposed mechanism is simple, robust, and comprehensive in its scope, and its key elements are well supported by empirical evidence.

  15. Duration of Greenland Stadial 22 and ice-gas Δage from counting of annual layers in Greenland NGRIP ice core

    Directory of Open Access Journals (Sweden)

    M. Bigler


    Full Text Available High-resolution measurements of chemical impurities and methane concentrations in Greenland ice core samples from the early glacial period allow the extension of annual-layer counted chronologies and the improvement of gas age-ice age difference (Δage essential to the synchronization of ice core records. We report high-resolution measurements of a 50 m section of the NorthGRIP ice core and corresponding annual layer thicknesses in order to constrain the duration of the Greenland Stadial 22 (GS-22 between Greenland Interstadials (GIs 21 and 22, for which inconsistent durations and ages have been reported from Greenland and Antarctic ice core records as well as European speleothems. Depending on the chronology used, GS-22 occurred between approximately 89 (end of GI-22 and 83 kyr b2k (onset of GI-21. From annual layer counting, we find that GS-22 lasted between 2696 and 3092 years and was followed by a GI-21 pre-cursor event lasting between 331 and 369 yr. Our layer-based counting agrees with the duration of stadial 22 as determined from the NALPS speleothem record (3250 ± 526 yr but not with that of the GICC05modelext chronology (2620 yr or an alternative chronology based on gas-marker synchronization to EPICA Dronning Maud Land ice core. These results show that GICC05modelext overestimates accumulation and/or underestimates thinning in this early part of the last glacial period. We also revise the possible ranges of NorthGRIP Δdepth (5.49 to 5.85 m and Δage (498 to 601 yr at the warming onset of GI-21 as well as the Δage range at the onset of the GI-21 precursor warming (523 to 654 yr, observing that temperature (represented by the δ15N proxy increases before CH4 concentration by no more than a few decades.

  16. Effects of nonlinear rheology, temperature and anisotropy on the relationship between age and depth at ice divides

    Directory of Open Access Journals (Sweden)

    C. Martín


    Full Text Available Ice flow in divide areas is strongly anisotropic. The evolution of ice fabric, from the onset of divide flow towards steady state with a fully developed fabric, has been shown to profoundly affect both the stratigraphy and surface topography of ice divides. Here, we investigate the effects of ice flow on the age-versus-depth relationship at ice divides by using a full Stokes thermomechanical model with a non-linear anisotropic constitutive relation between stress and strain rates. We compare our results with analytical approximations commonly employed in age–depth predictions, such as the Dansgaard and Lliboutry approximations. We show that these approximations systematically underestimate the age of ice at fully developed divides by as much as one order of magnitude. We also show that divides with fully developed fabric are ideal locations for ice-core extraction because ice under them can be up to one order of magnitude older than ice at the same depth at the flanks. In addition, these divides have a distinctive morphological structure that allows them to be clearly identified from satellite imagery or ground-penetrating radar data.

  17. Climate variations during the Medieval Warm Period and the Little Ice Age in Canada (United States)

    Ouellet-Bernier, M. M.; de Vernal, A.; Chartier, D.; Boucher, E.


    Climatic variations in Canada during the Medieval Warm Period and the Little Ice Age are analysed from multidisciplinary and multiproxy data (tree ring growth, glacier movements, varved sediments, lake microfossils, early instrumental data, documentary and discursive sources). They are examined in parallel with the critical relationship between human and their environment, with the aim to give a better portrait of climatic changes from different perspectives, taking into consideration regional and seasonal disparities and show long-term climate anomaly (proxy-data) and weather-related extreme events (human archives). The preliminary results of the compilation suggest that, in Canada, the Medieval Warm Period and the Little Ice Age were initiated earlier in the Western part and expended to the East and North. The Medieval Warm Period was recorded from 700-1000 AD to 1100-1300 AD. It lasted longer in Southern Canada ( 400 years) than in Northern Canada ( 200 years). The Little Ice Age was recorded from 1150-1300 AD to 1850 AD. It was characterized by 2 or 3 cooling pulses of 50 to 200 years each occurring around 1400-1450, 1600-1650 and 1800-1850 AD. Most of the reconstructions agreed with an ending in 1850 AD, with exception of the Eastern part of Canada where cold conditions were recorded until the late 19th century. The Year Without a Summer (1816) was recorded in most regions. It was associated with the Tambora eruption and amplified by cold conditions in early-19th century.

  18. Genomic evidence of widespread admixture from polar bears into brown bears during the last ice age. (United States)

    Cahill, James A; Heintzman, Peter D; Harris, Kelley; Teasdale, Matthew D; Kapp, Joshua; Soares, André E Rodrigues; Stirling, Ian; Bradley, Daniel; Edwards, Ceiridwen J; Graim, Kiley; Kisleika, Aliaksandr A; Malev, Alexander V; Monaghan, Nigel; Green, Richard E; Shapiro, Beth


    Recent genomic analyses have provided substantial evidence for past periods of gene flow from polar bears (Ursus maritimus) into Alaskan brown bears (Ursus arctos), with some analyses suggesting a link between climate change and genomic introgression. However, because it has mainly been possible to sample bears from the present day, the timing, frequency, and evolutionary significance of this admixture remains unknown. Here, we analyze genomic DNA from three additional and geographically distinct brown bear populations, including two that lived temporally close to the peak of the last ice age. We find evidence of admixture in all three populations, suggesting that admixture between these species has been common in their recent evolutionary history. In addition, analyses of ten fossil bears from the now-extinct Irish population indicate that admixture peaked during the last ice age, when brown bear and polar bear ranges overlapped. Following this peak, the proportion of polar bear ancestry in Irish brown bears declined rapidly until their extinction. Our results support a model in which ice age climate change created geographically widespread conditions conducive to admixture between polar bears and brown bears, as is again occurring today. We postulate that this model will be informative for many admixing species pairs impacted by climate change. Our results highlight the power of paleogenomics to reveal patterns of evolutionary change that are otherwise masked in contemporary data.

  19. Ice Ages

    Indian Academy of Sciences (India)

    earth was nearest to the sun in June (see Figure 1). About 22,000. J Srinivasan is a Professor both at Centre for. Atmospheric and Oceanic. Sciences and Department of Mechanical Engineer- ing at Indian Institute of. Science, Bangalore. His research interests include thermal science, atmospheric science and solar energy.

  20. Ice Ages

    Indian Academy of Sciences (India)

    nearest to the sun has var- ied with a period of 22,000 years. The earth is nearest to the sun in Decembernow but was nearest to the sun in June 11,000 years ago. GENERAL I ARTICLE. Mar 21. June21 I - - - - - - - - - - - - - f e t - - - - - ; Dec.21. Present. Sepl21. Dec.21. Mar.21 I---------------I.r-------! Sap.21. 5500 years ago.

  1. Ice Sheets & Ice Cores

    DEFF Research Database (Denmark)

    Mikkelsen, Troels Bøgeholm

    Since the discovery of the Ice Ages it has been evident that Earth’s climate is liable to undergo dramatic changes. The previous climatic period known as the Last Glacial saw large oscillations in the extent of ice sheets covering the Northern hemisphere. Understanding these oscillations known...

  2. Atmospheric gas records from Taylor Glacier, Antarctica, reveal ancient ice with ages spanning the entire last glacial cycle

    Directory of Open Access Journals (Sweden)

    D. Baggenstos


    Full Text Available Old ice for paleo-environmental studies, traditionally accessed through deep core drilling on domes and ridges on the large ice sheets, can also be retrieved at the surface from ice sheet margins and blue ice areas. The practically unlimited amount of ice available at these sites satisfies a need in the community for studies of trace components requiring large sample volumes. For margin sites to be useful as ancient ice archives, the ice stratigraphy needs to be understood and age models need to be established. We present measurements of trapped gases in ice from Taylor Glacier, Antarctica, to date the ice and assess the completeness of the stratigraphic section. Using δ18O of O2 and methane concentrations, we unambiguously identify ice from the last glacial cycle, covering every climate interval from the early Holocene to the penultimate interglacial. A high-resolution transect reveals the last deglaciation and the Last Glacial Maximum (LGM in detail. We observe large-scale deformation in the form of folding, but individual stratigraphic layers do not appear to have undergone irregular thinning. Rather, it appears that the entire LGM–deglaciation sequence has been transported from the interior of the ice sheet to the surface of Taylor Glacier relatively undisturbed. We present an age model that builds the foundation for gas studies on Taylor Glacier. A comparison with the Taylor Dome ice core confirms that the section we studied on Taylor Glacier is better suited for paleo-climate reconstructions of the LGM due to higher accumulation rates.

  3. Cosmogenic nuclide age estimate for Laurentide Ice Sheet recession from the terminal moraine, New Jersey, USA, and constraints on latest Pleistocene ice sheet history (United States)

    Corbett, Lee B.; Bierman, Paul R.; Stone, Byron D.; Caffee, Marc W.; Larsen, Patrick L.


    The time at which the Laurentide Ice Sheet reached its maximum extent and subsequently retreated from its terminal moraine in New Jersey has been constrained by bracketing radiocarbon ages on preglacial and postglacial sediments. Here, we present measurements of in situ produced 10Be and 26Al in 16 quartz-bearing samples collected from bedrock outcrops and glacial erratics just north of the terminal moraine in north-central New Jersey; as such, our ages represent a minimum limit on the timing of ice recession from the moraine. The data set includes field and laboratory replicates, as well as replication of the entire data set five years after initial measurement. We find that recession of the Laurentide Ice Sheet from the terminal moraine in New Jersey began before 25.2±2.1 ka (10Be, n=16, average, 1 standard deviation). This cosmogenic nuclide exposure age is consistent with existing limiting radiocarbon ages in the study area and cosmogenic nuclide exposure ages from the terminal moraine on Martha’s Vineyard ~300 km to the northeast. The age we propose for Laurentide Ice Sheet retreat from the New Jersey terminal position is broadly consistent with regional and global climate records of the last glacial maximum termination and records of fluvial incision.

  4. Geochemical record of high emperor penguin populations during the Little Ice Age at Amanda Bay, Antarctica

    International Nuclear Information System (INIS)

    Huang, Tao; Yang, Lianjiao; Chu, Zhuding; Sun, Liguang; Yin, Xijie


    Emperor penguins (Aptenodytes forsteri) are sensitive to the Antarctic climate change because they breed on the fast sea ice. Studies of paleohistory for the emperor penguin are rare, due to the lack of archives on land. In this study, we obtained an emperor penguin ornithogenic sediment profile (PI) and performed geochronological, geochemical and stable isotope analyses on the sediments and feather remains. Two radiocarbon dates of penguin feathers in PI indicate that emperor penguins colonized Amanda Bay as early as CE 1540. By using the bio-elements (P, Se, Hg, Zn and Cd) in sediments and stable isotope values (δ 15 N and δ 13 C) in feathers, we inferred relative population size and dietary change of emperor penguins during the period of CE 1540–2008, respectively. An increase in population size with depleted N isotope ratios for emperor penguins on N island at Amanda Bay during the Little Ice Age (CE 1540–1866) was observed, suggesting that cold climate affected the penguin's breeding habitat, prey availability and thus their population and dietary composition. - Highlights: • Emperor penguin colonized at Amanda Bay, East Antarctic as early as AD 1540. • Populations of emperor penguin at Amanda Bay increase during the little ice age. • Depleted N isotope ratios of Emperor penguins during the LIA were observed.

  5. Geochemical record of high emperor penguin populations during the Little Ice Age at Amanda Bay, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Tao, E-mail: [School of Resources and Environmental Engineering, Anhui University, Hefei 230601 (China); School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Yang, Lianjiao; Chu, Zhuding [School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Sun, Liguang, E-mail: [School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Yin, Xijie [Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005 (China)


    Emperor penguins (Aptenodytes forsteri) are sensitive to the Antarctic climate change because they breed on the fast sea ice. Studies of paleohistory for the emperor penguin are rare, due to the lack of archives on land. In this study, we obtained an emperor penguin ornithogenic sediment profile (PI) and performed geochronological, geochemical and stable isotope analyses on the sediments and feather remains. Two radiocarbon dates of penguin feathers in PI indicate that emperor penguins colonized Amanda Bay as early as CE 1540. By using the bio-elements (P, Se, Hg, Zn and Cd) in sediments and stable isotope values (δ{sup 15}N and δ{sup 13}C) in feathers, we inferred relative population size and dietary change of emperor penguins during the period of CE 1540–2008, respectively. An increase in population size with depleted N isotope ratios for emperor penguins on N island at Amanda Bay during the Little Ice Age (CE 1540–1866) was observed, suggesting that cold climate affected the penguin's breeding habitat, prey availability and thus their population and dietary composition. - Highlights: • Emperor penguin colonized at Amanda Bay, East Antarctic as early as AD 1540. • Populations of emperor penguin at Amanda Bay increase during the little ice age. • Depleted N isotope ratios of Emperor penguins during the LIA were observed.

  6. New age constraints for the Saalian glaciation in northern central Europe: Implications for the extent of ice sheets and related proglacial lake systems (United States)

    Lang, Jörg; Lauer, Tobias; Winsemann, Jutta


    A comprehensive palaeogeographic reconstruction of ice sheets and related proglacial lake systems for the older Saalian glaciation in northern central Europe is presented, which is based on the integration of palaeo-ice flow data, till provenance, facies analysis, geomorphology and new luminescence ages of ice-marginal deposits. Three major ice advances with different ice-advance directions and source areas are indicated by palaeo-ice flow directions and till provenance. The first ice advance was characterised by a southwards directed ice flow and a dominance of clasts derived from southern Sweden. The second ice advance was initially characterised by an ice flow towards the southwest. Clasts are mainly derived from southern and central Sweden. The latest stage in the study area (third ice advance) was characterised by ice streaming (Hondsrug ice stream) in the west and a re-advance in the east. Clasts of this stage are mainly derived from eastern Fennoscandia. Numerical ages for the first ice advance are sparse, but may indicate a correlation with MIS 8 or early MIS 6. New pIRIR290 luminescence ages of ice-marginal deposits attributed to the second ice advance range from 175 ± 10 to 156 ± 24 ka and correlate with MIS 6. The ice sheets repeatedly blocked the main river-drainage pathways and led to the formation of extensive ice-dammed lakes. The formation of proglacial lakes was mainly controlled by ice-damming of river valleys and major bedrock spillways; therefore the lake levels and extends were very similar throughout the repeated ice advances. During deglaciation the lakes commonly increased in size and eventually drained successively towards the west and northwest into the Lower Rhine Embayment and the North Sea. Catastrophic lake-drainage events occurred when large overspill channels were suddenly opened. Ice-streaming at the end of the older Saalian glaciation was probably triggered by major lake-drainage events.

  7. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Ice Thickness and Age Environmental Data Records (EDRs) from NDE (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Ice Thickness and Age from the Visible Infrared Imaging Radiometer Suite (VIIRS)...

  8. 77 FR 14567 - Draft General Management Plan/Environmental Impact Statement for the Ice Age Complex at Cross... (United States)


    ... Internet through the Web site above. You may also send comments to Superintendent, Ice Age National Scenic... providing visitors with interpretation of the evolution of the complex from the last glacial retreat to the...

  9. Forests of Wisconsin, 2013 (United States)

    Charles H. Perry


    This resource update provides an overview of forest resources in Wisconsin based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Northern Research Station in cooperation with the Wisconsin Department of Natural Resources. Data estimates are based on field data collected using the FIA annualized sample design and...

  10. Precise interpolar phasing of abrupt climate change during the last ice age (United States)

    ,; Buizert, Christo; Adrian, Betty M.; Ahn, Jinho; Albert, Mary; Alley, Richard B.; Baggenstos, Daniel; Bauska, Thomas K.; Bay, Ryan C.; Bencivengo, Brian B.; Bentley, Charles R.; Brook, Edward J.; Chellman, Nathan J.; Clow, Gary D.; Cole-Dai, Jihong; Conway, Howard; Cravens, Eric; Cuffey, Kurt M.; Dunbar, Nelia W.; Edwards, Jon S.; Fegyveresi, John M.; Ferris, Dave G.; Fitzpatrick, Joan J.; Fudge, T. J.; Gibson, Chris J.; Gkinis, Vasileios; Goetz, Joshua J.; Gregory, Stephanie; Hargreaves, Geoffrey Mill; Iverson, Nels; Johnson, Jay A.; Jones, Tyler R.; Kalk, Michael L.; Kippenhan, Matthew J.; Koffman, Bess G.; Kreutz, Karl; Kuhl, Tanner W.; Lebar, Donald A.; Lee, James E.; Marcott, Shaun A.; Markle, Bradley R.; Maselli, Olivia J.; McConnell, Joseph R.; McGwire, Kenneth C.; Mitchell, Logan E.; Mortensen, Nicolai B.; Neff, Peter D.; Nishiizumi, Kunihiko; Nunn, Richard M.; Orsi, Anais J.; Pasteris, Daniel R.; Pedro, Joel B.; Pettit, Erin C.; Price, P. Buford; Priscu, John C.; Rhodes, Rachael H.; Rosen, Julia L.; Schauer, Andrew J.; Schoenemann, Spruce W.; Sendelbach, Paul J.; Severinghaus, Jeffrey P.; Shturmakov, Alexander J.; Sigl, Michael; Slawny, Kristina R.; Souney, Joseph M.; Sowers, Todd A.; Spencer, Matthew K.; Steig, Eric J.; Taylor, Kendrick C.; Twickler, Mark S.; Vaughn, Bruce H.; Voigt, Donald E.; Waddington, Edwin D.; Welten, Kees C.; Wendricks, Anthony W.; White, James W. C.; Winstrup, Mai; Wong, Gifford J.; Woodruff, Thomas E.


    The last glacial period exhibited abrupt Dansgaard–Oeschger climatic oscillations, evidence of which is preserved in a variety of Northern Hemisphere palaeoclimate archives1. Ice cores show that Antarctica cooled during the warm phases of the Greenland Dansgaard–Oeschger cycle and vice versa2, 3, suggesting an interhemispheric redistribution of heat through a mechanism called the bipolar seesaw4, 5, 6. Variations in the Atlantic meridional overturning circulation (AMOC) strength are thought to have been important, but much uncertainty remains regarding the dynamics and trigger of these abrupt events7, 8, 9. Key information is contained in the relative phasing of hemispheric climate variations, yet the large, poorly constrained difference between gas age and ice age and the relatively low resolution of methane records from Antarctic ice cores have so far precluded methane-based synchronization at the required sub-centennial precision2, 3,10. Here we use a recently drilled high-accumulation Antarctic ice core to show that, on average, abrupt Greenland warming leads the corresponding Antarctic cooling onset by 218 ± 92 years (2σ) for Dansgaard–Oeschger events, including the Bølling event; Greenland cooling leads the corresponding onset of Antarctic warming by 208 ± 96 years. Our results demonstrate a north-to-south directionality of the abrupt climatic signal, which is propagated to the Southern Hemisphere high latitudes by oceanic rather than atmospheric processes. The similar interpolar phasing of warming and cooling transitions suggests that the transfer time of the climatic signal is independent of the AMOC background state. Our findings confirm a central role for ocean circulation in the bipolar seesaw and provide clear criteria for assessing hypotheses and model simulations of Dansgaard–Oeschger dynamics.

  11. An abrupt weakening of the subpolar gyre as trigger of Little Ice Age-type episodes (United States)

    Moreno-Chamarro, Eduardo; Zanchettin, Davide; Lohmann, Katja; Jungclaus, Johann H.


    We investigate the mechanism of a decadal-scale weakening shift in the strength of the subpolar gyre (SPG) that is found in one among three last millennium simulations with a state-of-the-art Earth system model. The SPG shift triggers multicentennial anomalies in the North Atlantic climate driven by long-lasting internal feedbacks relating anomalous oceanic and atmospheric circulation, sea ice extent, and upper-ocean salinity in the Labrador Sea. Yet changes throughout or after the shift are not associated with a persistent weakening of the Atlantic Meridional Overturning Circulation or shifts in the North Atlantic Oscillation. The anomalous climate state of the North Atlantic simulated after the shift agrees well with climate reconstructions from within the area, which describe a transition between a stronger and weaker SPG during the relatively warm medieval climate and the cold Little Ice Age respectively. However, model and data differ in the timing of the onset. The simulated SPG shift is caused by a rapid increase in the freshwater export from the Arctic and associated freshening in the upper Labrador Sea. Such freshwater anomaly relates to prominent thickening of the Arctic sea ice, following the cluster of relatively small-magnitude volcanic eruptions by 1600 CE. Sensitivity experiments without volcanic forcing can nonetheless produce similar abrupt events; a necessary causal link between the volcanic cluster and the SPG shift can therefore be excluded. Instead, preconditioning by internal variability explains discrepancies in the timing between the simulated SPG shift and the reconstructed estimates for the Little Ice Age onset.

  12. Holocene glacial history of the west Greenland Ice Sheet inferred from cosmogenic exposure ages and threshold lakes

    DEFF Research Database (Denmark)

    Larsen, Nicolaj Krog; Kjaer, K. H.; Colding, Sune Oluf


    In this study, we use a combination of 10Be exposure ages and threshold lakes to constrain the ice sheet history in Godthåbs- and Buksefjorden, west Greenland (63-64°N) during the Holocene. The 10Be cosmogenic exposure ages have been used to quantify both the ice retreat and thinning of the west......) and this suggest that the ice sheet in this area may have been more retracted and probably more sensitive to climate change than other areas in south and west Greenland....

  13. Regeneration of Little Ice Age bryophytes emerging from a polar glacier with implications of totipotency in extreme environments. (United States)

    La Farge, Catherine; Williams, Krista H; England, John H


    Across the Canadian Arctic Archipelago, widespread ice retreat during the 20th century has sharply accelerated since 2004. In Sverdrup Pass, central Ellesmere Island, rapid glacier retreat is exposing intact plant communities whose radiocarbon dates demonstrate entombment during the Little Ice Age (1550-1850 AD). The exhumed bryophyte assemblages have exceptional structural integrity (i.e., setae, stem structures, leaf hair points) and have remarkable species richness (60 of 144 extant taxa in Sverdrup Pass). Although the populations are often discolored (blackened), some have developed green stem apices or lateral branches suggesting in vivo regrowth. To test their biological viability, Little Ice Age populations emerging from the ice margin were collected for in vitro growth experiments. Our results include a unique successful regeneration of subglacial bryophytes following 400 y of ice entombment. This finding demonstrates the totipotent capacity of bryophytes, the ability of a cell to dedifferentiate into a meristematic state (analogous to stem cells) and develop a new plant. In polar ecosystems, regrowth of bryophyte tissue buried by ice for 400 y significantly expands our understanding of their role in recolonization of polar landscapes (past or present). Regeneration of subglacial bryophytes broadens the concept of Ice Age refugia, traditionally confined to survival of land plants to sites above and beyond glacier margins. Our results emphasize the unrecognized resilience of bryophytes, which are commonly overlooked vis-a-vis their contribution to the establishment, colonization, and maintenance of polar terrestrial ecosystems.

  14. Little Ice Age glacial geomorphology and sedimentology of Portage Glacier, South-Central Alaska

    Directory of Open Access Journals (Sweden)

    Carlos Córdova


    Full Text Available The study of glacial landforms and deposits is important, as it isdifficult to observe processes under modern glaciers and ice-sheets. Thus landscapes and sediments that are the product of present glaciation can give insight into processes that occurred during Pleistocene times. This study investigates the genesis of little ice age glacial landforms present in Portage Glacier, South-Central Alaska. The present day moraine morphology and sedimentology in Portage Glacier valley reveals the presence of two types of till and moraines. The clast-rich sandy diamicton present on the 1852 moraine is interpreted to be a basal till indicating this feature is a pushmoraine representing an advance or a standstill position of Portage Glacier in 1852. The moderately sorted gray sandy boulder gravel present on the 1900 and 1922 moraines is interpreted to be an ice-marginal deposit (ablation till with a mixture of supraglacial and glaciofluvial sediments deposited by slumping and stream sortingprocesses. All of these features are interpreted to be ablation moraines representing glacier retreat and moraine building in 1900 and1922.

  15. Future ice ages and the challenges related to final disposal of nuclear waste: The Greenland Ice Sheet Hydrology Project (United States)

    Lehtinen, A.; Claesson-Liljedahl, L.; Näslund, J.-O.; Ruskeeniemi, T.


    A deep geological repository for nuclear waste is designed to keep radiotoxic material separated from mankind and the environment for several hundreds of thousands of years. Within this time perspective glacial conditions are expected in high latitudes/Canada and North Europe. Climate induced changes such as the growth of ice sheets and permafrost will influence and alter the ground surface and subsurface environment, which may impact repository safety. In order to understand how climate change, particularly cooling and glaciation, might affect a repository in the long term, the use of present-day analogues helps to reduce the uncertainties and support the assumptions made in safety assessments. There are major uncertainties concerning hydrological processes related to glacial conditions. The impact of glaciations on any planned repository is a key consideration when performing safety assessments as it is one of the strongest perturbations related to climate change in the long term. The main aspects that need to be further investigated include: 1) to what extent does the meltwater produced by an ice sheet penetrates into the bedrock; 2) what is the pressure situation under an ice sheet, driving ground water flow; 3) how much oxygenated water will reach repository depth; 4) to what depth does glacial meltwater penetrate into the bedrock ; 5)what chemical composition does such water has when and if it reaches repository depth; and 6) can taliks (unfrozen ground in a permafrost area) act as concentrated discharge points of deep groundwater potentially transporting radionuclides in case of repository failure? Field data is needed in order to achieve a better and integrated understanding of the problems discussed above. Thus, research in a natural analogue site in Greenland has been planned and initiated by the Finnish (Posiva), Swedish (SKB) and Canadian (NWMO) nuclear waste management companies. The Greenland ice sheet and the Kangerlussuaq area (west Greenland

  16. Aeolian stratigraphy describes ice-age paleoenvironments in unglaciated Arctic Alaska (United States)

    Gaglioti, Benjamin V.; Mann, Daniel H.; Groves, Pamela; Kunz, Michael L.; Farquharson, Louise M.; Reanier, Richard E.; Jones, Benjamin M.; Wooller, Matthew J.


    Terrestrial paleoenvironmental records with high dating resolution extending into the last ice age are rare from the western Arctic. Such records can test the synchronicity and extent of ice-age climatic events and define how Arctic landscapes respond to rapid climate changes. Here we describe the stratigraphy and sedimentology of a yedoma deposit in Arctic Alaska (the Carter Section) dating to between 37,000 and 9000 calibrated radiocarbon years BP (37-9 ka) and containing detailed records of loess and sand-sheet sedimentation, soil development, carbon storage, and permafrost dynamics. Alternation between sand-sheet and loess deposition provides a proxy for the extent and activity of the Ikpikpuk Sand Sea (ISS), a large dune field located immediately upwind. Warm, moist interstadial times (ca. 37, 36.3-32.5, and 15-13 ka) triggered floodplain aggradation, permafrost thaw, reduced loess deposition, increased vegetation cover, and rapid soil development accompanied by enhanced carbon storage. During the Last Glacial Maximum (LGM, ca. 28-18 ka), rapid loess deposition took place on a landscape where vegetation was sparse and non-woody. The most intense aeolian activity occurred after the LGM between ca. 18 and 15 ka when sand sheets fringing the ISS expanded over the site, possibly in response to increasingly droughty conditions as summers warmed and active layers deepened. With the exception of this lagged LGM response, the record of aeolian activity at the Carter Section correlates with other paleoenvironmental records from unglaciated Siberia and Alaska. Overall, rapid shifts in geomorphology, soils, vegetation, and permafrost portray an ice-age landscape where, in contrast to the Holocene, environmental change was chronic and dominated by aeolian processes.

  17. Die Deutschen in Wisconsin (Germans in Wisconsin). (United States)

    Wisconsin State Dept. of Public Instruction, Madison.

    The following curriculum units comprise this course book: (1) Germans in a New Home, (2) Contributions of the Germans in Wisconsin, (3) A Letter to Germany, (4) Germans Come to Kingston, (5) First a Soldier, Then a Man of the Church (about Heinrich von Rohr), (6) A Visiting German, and (7) Germans and Music. Each unit begins with a reading of…

  18. No iron fertilization in the equatorial Pacific Ocean during the last ice age. (United States)

    Costa, K M; McManus, J F; Anderson, R F; Ren, H; Sigman, D M; Winckler, G; Fleisher, M Q; Marcantonio, F; Ravelo, A C


    The equatorial Pacific Ocean is one of the major high-nutrient, low-chlorophyll regions in the global ocean. In such regions, the consumption of the available macro-nutrients such as nitrate and phosphate is thought to be limited in part by the low abundance of the critical micro-nutrient iron. Greater atmospheric dust deposition could have fertilized the equatorial Pacific with iron during the last ice age--the Last Glacial Period (LGP)--but the effect of increased ice-age dust fluxes on primary productivity in the equatorial Pacific remains uncertain. Here we present meridional transects of dust (derived from the (232)Th proxy), phytoplankton productivity (using opal, (231)Pa/(230)Th and excess Ba), and the degree of nitrate consumption (using foraminifera-bound δ(15)N) from six cores in the central equatorial Pacific for the Holocene (0-10,000 years ago) and the LGP (17,000-27,000 years ago). We find that, although dust deposition in the central equatorial Pacific was two to three times greater in the LGP than in the Holocene, productivity was the same or lower, and the degree of nitrate consumption was the same. These biogeochemical findings suggest that the relatively greater ice-age dust fluxes were not large enough to provide substantial iron fertilization to the central equatorial Pacific. This may have been because the absolute rate of dust deposition in the LGP (although greater than the Holocene rate) was very low. The lower productivity coupled with unchanged nitrate consumption suggests that the subsurface major nutrient concentrations were lower in the central equatorial Pacific during the LGP. As these nutrients are today dominantly sourced from the Subantarctic Zone of the Southern Ocean, we propose that the central equatorial Pacific data are consistent with more nutrient consumption in the Subantarctic Zone, possibly owing to iron fertilization as a result of higher absolute dust fluxes in this region. Thus, ice-age iron fertilization in the

  19. End of the Little Ice Age in the Alps forced by industrial black carbon


    Painter, Thomas H.; Flanner, Mark G.; Kaser, Georg; Marzeion, Ben; VanCuren, Richard A.; Abdalati, Waleed


    The end of the Little Ice Age in the European Alps has long been a paradox to glaciology and climatology. Glaciers in the Alps began to retreat abruptly in the mid-19th century, but reconstructions of temperature and precipitation indicate that glaciers should have instead advanced into the 20th century. We observe that industrial black carbon in snow began to increase markedly in the mid-19th century and show with simulations that the associated increases in absorbed sunlight by black carbon...

  20. Spatial pattern of mass loss processes across the Greenland Ice Sheet from the Little Ice Age to 2010

    DEFF Research Database (Denmark)

    Kjaer, K. H.; Korsgaard, N. J.; Kjeldsen, K. K.

    The Greenland Ice Sheet loses mass through surface meltwater runoff and discharge from marine terminating outlet glaciers. The spatial variability and magnitude of these processes have been studied and described in detail for the past decades. Here, we combine the mass loss between the LIA to 2010...... (ICESat) from 2003-2009, NASA's Land, Vegetation, and Ice Sensor (LVIS) from 2010, and ASTER (Silcast AST14DMO) co-registered to ICESat, to estimate mass loss throughout the 20th and early 21st Century. The mass balance estimates of the GrIS since retreat from maximum LIA is combined with a SMB model...... correspond to those that experienced considerable thinning throughout the 20th century. Consequently, comparing the 20th century thinning pattern to that of the last decade, and assuming a similar warming pattern, we argue that the present sensitivity distribution will hold also for future ice sheet mass...

  1. Ground-layer plant community responses to even-age and uneven-age silvicultural treatments in Wisconsin northern hardwood forests (United States)

    Cristel C. Kern; Brian J. Palik; Terry F. Strong


    We evaluated ground-layer plant diversity and community composition in northern hardwood forests among uncut controls and stands managed with even-age or uneven-age silvicultural systems. Even-age treatments included diameter-limit cuttings (20-cm diameter at 30-cm stem height) in 1952 and shelterwood removals in 1964. Uneven-age treatments included three intensities...

  2. Countering Ice Ages: Re-directing Public Concern from Global Warming (GW) to Global Cooling (GC) (United States)

    Singer, S. F.


    I present here three arguments in favor of such a drastic shift - which involves also a shift in current policies, such as mitigation of the greenhouse (GH) gas carbon dioxide. 1. Historical evidence shows that cooling, even on a regional or local scale, is much more damaging than warming. The key threat is to agriculture, leading to failure of harvests, followed by famine, starvation, disease, and mass deaths. 2. Also, GC is reasonably sure, while GW is iffy. The evidence from deep-sea sediment cores and ice cores shows some 17 (Milankovitch-style) glaciations in the past 2 million years, each typically lasting 100,000 years, interrupted by warm inter-glacials, typically around 10,000-yr duration. The most recent glaciation ended rather suddenly about 12,000 years ago. We are now in the warm Holocene, which is expected to end soon. Most of humanity may not survive the next, inevitable glaciation. We need to consider also the warming-cooling (Dansgaard-Oeschger-Bond - DOB) cycles, which seem solar-controlled and have a period of approx 1000-1500 years; its most recent cooling phase, the "Little Ice Age" (LIA), ended about 200 years ago. For details, see Unstoppable Global Warming: Every 1500 years by Singer &Avery [2007]. 3. Available technology seems adequate to assure human survival - at least in industrialized nations. The main threat is warfare, driven by competition for food and other essential resources. With nuclear weapons and delivery systems widely dispersed, the outcome of future wars is difficult to predict. Using geo-engineering to overcome a future cooling looks promising for both types of ice ages - with relatively low cost and low risk to the physical and biological environment. I will describe how to neutralize the "trigger" of major glaciations, and propose a particular greenhouse scheme that may counter the cooling phase of DOB cycles.

  3. Pollen from the Deep-Sea: A Breakthrough in the Mystery of the Ice Ages

    Directory of Open Access Journals (Sweden)

    María F. Sánchez Goñi


    -air/warm-sea decoupling events occurred on the European margin superimposed to a long-term air-sea decoupling trend. Strong air-sea thermal contrasts promoted the production of water vapor that was then transported northward by the westerlies and fed ice sheets. This interaction between long-term and shorter time-scale climatic variability may have amplified insolation decreases and thus explain the Ice Ages. This hypothesis should be tested by the integration of stochastic processes in Earth models of intermediate complexity.

  4. Pollen from the Deep-Sea: A Breakthrough in the Mystery of the Ice Ages. (United States)

    Sánchez Goñi, María F; Desprat, Stéphanie; Fletcher, William J; Morales-Molino, César; Naughton, Filipa; Oliveira, Dulce; Urrego, Dunia H; Zorzi, Coralie


    occurred on the European margin superimposed to a long-term air-sea decoupling trend. Strong air-sea thermal contrasts promoted the production of water vapor that was then transported northward by the westerlies and fed ice sheets. This interaction between long-term and shorter time-scale climatic variability may have amplified insolation decreases and thus explain the Ice Ages. This hypothesis should be tested by the integration of stochastic processes in Earth models of intermediate complexity.

  5. Barns of Wisconsin (United States)

    Watson-Newlin, Karen


    In this article, the author shares a painting unit she introduced to her students. In this unit, her students painted pictures of barns and discussed the historical significance of barns in Wisconsin.

  6. Medieval Warm Period and Little Ice Age Signatures in the Distribution of Modern Ocean Temperatures (United States)

    Gebbie, G.; Huybers, P. J.


    It is well established both that global temperatures have varied overthe last millenium and that the interior ocean reflects surfaceproperties inherited over these timescales. Signatures of theMedieval Warm Period and Little Ice Age are thus to be expected in themodern ocean state, though the magnitude of these effects and whetherthey are detectable is unclear. Analysis of changes in temperatureacross those obtained in the 1870s as part of the theH.M.S. Challenger expedition, the 1990s World Ocean CirculationExperiment, and recent Argo observations shows a consistent pattern:the upper ocean and Atlantic have warmed, but the oldest waters inthe deep Pacific appear to have cooled. The implications of pressureeffects on the H.M.S. Challenger thermometers and uncertainties indepth of observations are non-negligible but do not appear tofundamentally alter this pattern. Inversion of the modern hydrographyusing ocean transport estimates derived from passive tracer andradiocarbon observations indicates that deep Pacific cooling could bea vestige of the Medieval Warm Period, and that warming elsewhere reflects thecombined effects of emergence from the Little Ice Age and modernanthropogenic warming. Implications for longterm variations in oceanheat uptake and separating natural and anthropogenic contributions to themodern energy imbalance are discussed.

  7. Quantitative Biostratigraphic Age Control of Glacimarine Sediments, ANDRILL 1B Drillcore, McMurdo Ice Shelf (United States)

    Cody, R.; Levy, R.; Crampton, J.; Wilson, G.; Naish, T.; Harwood, D.; Winter, D.; Scherer, R.


    Interpretation of glacimarine sedimentary records from Antarctic shelf drillholes has been greatly hampered by the ambiguous age of strata where erosional unconformities and coarse diamictite deposits truncate or omit the mangetostratigraphic and biostratigraphic units used for correlation. However, new quantitative biostratigraphic techniques enable the correlation of sparse, incomplete, and reworking-prone Plio- Pleistocene records of Ross Sea fossil diatom flora with the more extensively documented but potentially diachronous offshore history of species' first and last appearances (FAs and LAs). The approach uses a comprehensive regional database of fossil records and computer-automated search algorithms to (a) find the multidimensional line of correlation (LOC) that best fits local observations, and (b) map out confidence intervals based on the full range of equally parsimonious composite FA/LA sequences and local range-end adjustments. An integrated, quantitative chronostratigraphic model for the AND-1B drillcore was constructed iteratively: the initial LOC was based solely on preliminary on-ice observations of fossil diatom highest and lowest occurrences (HOs and LOs) and their correlation with a database of other local event records from 24 DVDP, CIROS, and IODP drillcore sections. The model was subsequently updated as off-ice work yielded additional biostratigraphic marker events and revised event horizons, Ar/Ar ages for volcanic material, better- constrained magnetostratigraphic interpretations, and refinements to computational/analytical methodology. The current quantitative biostratigraphic age model for the AND-1B hole integrates the local ranges of 29 diatom taxa, 5 dated ashes, and independently constrained ages of 5 paleomagnetic reversals. Results corroborate almost all of the on-ice geomagnetic polarity reversal age interpretations, but identify a previously unrecognized major disconformity (~800kyr hiatus) near 440mbsf. It is significant to note

  8. Radiostratigraphy and Age Structure of the Greenland Ice Sheet V001 (United States)

    National Aeronautics and Space Administration — This data set contains the traced deep radiostratigraphy of the Greenland Ice Sheet from airborne deep ice-penetrating radar data collected by The University of...

  9. Geochemical record of high emperor penguin populations during the Little Ice Age at Amanda Bay, Antarctica. (United States)

    Huang, Tao; Yang, Lianjiao; Chu, Zhuding; Sun, Liguang; Yin, Xijie


    Emperor penguins (Aptenodytes forsteri) are sensitive to the Antarctic climate change because they breed on the fast sea ice. Studies of paleohistory for the emperor penguin are rare, due to the lack of archives on land. In this study, we obtained an emperor penguin ornithogenic sediment profile (PI) and performed geochronological, geochemical and stable isotope analyses on the sediments and feather remains. Two radiocarbon dates of penguin feathers in PI indicate that emperor penguins colonized Amanda Bay as early as CE 1540. By using the bio-elements (P, Se, Hg, Zn and Cd) in sediments and stable isotope values (δ(15)N and δ(13)C) in feathers, we inferred relative population size and dietary change of emperor penguins during the period of CE 1540-2008, respectively. An increase in population size with depleted N isotope ratios for emperor penguins on N island at Amanda Bay during the Little Ice Age (CE 1540-1866) was observed, suggesting that cold climate affected the penguin's breeding habitat, prey availability and thus their population and dietary composition. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Increase in penguin populations during the Little Ice Age in the Ross Sea, Antarctica. (United States)

    Hu, Qi-Hou; Sun, Li-Guang; Xie, Zhou-Qing; Emslie, Steven D; Liu, Xiao-Dong


    Penguins are an important seabird species in Antarctica and are sensitive to climate and environmental changes. Previous studies indicated that penguin populations increased when the climate became warmer and decreased when it became colder in the maritime Antarctic. Here we determined organic markers in a sediment profile collected at Cape Bird, Ross Island, high Antarctic, and reconstructed the history of Adélie penguin colonies at this location over the past 700 years. The region transformed from a seal to a penguin habitat when the Little Ice Age (LIA; 1500-1800 AD) began. Penguins then became the dominant species. Penguin populations were the highest during ca. 1490 to 1670 AD, a cold period, which is contrary to previous results in other regions much farther north. Different responses to climate change may occur at low latitudes and high latitudes in the Antarctic, even if for same species.

  11. Pacemaking the ice ages by frequency modulation of Earth's orbital eccentricity (United States)



    Evidence from power spectra of deep-sea oxygen isotope time series suggests that the climate system of Earth responds nonlinearly to astronomical forcing by frequency modulating eccentricity-related variations in insolation. With the help of a simple model, it is shown that frequency modulation of the approximate 100,000-year eccentricity cycles by the 413,000-year component accounts for the variable duration of the ice ages, the multiple-peak character of the time series spectra, and the notorious absence of significant spectral amplitude at the 413,000-year period. The observed spectra are consistent with the classic Milankovitch theories of insolation, so that climate forcing by 100,000-year variations in orbital inclination that cause periodic dust accretion appear unnecessary.


    Directory of Open Access Journals (Sweden)

    S. B. Kroonenberg


    Full Text Available The researches combining a social, economic and ecological content, find out a generality of appendix area and global purpose. This purpose image is hidden behind the term sustainable development". These restrictions are presented as the multiplicative index of the development. This index is reflecting an information balance of a territory.The level of the Caspian Sea, the largest inland sea in the world, has fluctuated capriciously in history, with amplitudes up to 3 m in the last century, to 25m in the last millennium, and to over 150m since the Last Glacial. The results suggest that the last major highstands occurred around 2600 BP and in the Little Ice Age and coincide with global cooling events associated with minima in solar activity. This suggests that millennial precipitation changes in the Volga River drainage basin are also forced by solar activity.

  13. Correcting anthropogenic ocean heat uptake estimates for the Little Ice Age (United States)

    Gebbie, Geoffrey


    Estimates of anthropogenic ocean heat uptake typically assume that the ocean was in equilibrium during the pre-industrial era. Recent reconstructions of the Common Era, however, show a multi-century surface cooling trend before the Industrial Revolution. Using a time-evolving state estimation method, we find that the 1750 C.E. ocean must have been out of equilibrium in order to fit the H.M.S. Challenger, WOCE, and Argo hydrographic data. When the disequilibrated ocean conditions are taken into account, the inferred ocean heat uptake from 1750-2014 C.E. is revised due to the deep ocean memory of Little Ice Age surface forcing. These effects of ocean disequilibrium should also be considered when interpreting climate sensitivity estimates.

  14. End of the Little Ice Age in the Alps forced by industrial black carbon. (United States)

    Painter, Thomas H; Flanner, Mark G; Kaser, Georg; Marzeion, Ben; VanCuren, Richard A; Abdalati, Waleed


    Glaciers in the European Alps began to retreat abruptly from their mid-19th century maximum, marking what appeared to be the end of the Little Ice Age. Alpine temperature and precipitation records suggest that glaciers should instead have continued to grow until circa 1910. Radiative forcing by increasing deposition of industrial black carbon to snow may represent the driver of the abrupt glacier retreats in the Alps that began in the mid-19th century. Ice cores indicate that black carbon concentrations increased abruptly in the mid-19th century and largely continued to increase into the 20th century, consistent with known increases in black carbon emissions from the industrialization of Western Europe. Inferred annual surface radiative forcings increased stepwise to 13-17 W⋅m(-2) between 1850 and 1880, and to 9-22 W⋅m(-2) in the early 1900s, with snowmelt season (April/May/June) forcings reaching greater than 35 W⋅m(-2) by the early 1900s. These snowmelt season radiative forcings would have resulted in additional annual snow melting of as much as 0.9 m water equivalent across the melt season. Simulations of glacier mass balances with radiative forcing-equivalent changes in atmospheric temperatures result in conservative estimates of accumulating negative mass balances of magnitude -15 m water equivalent by 1900 and -30 m water equivalent by 1930, magnitudes and timing consistent with the observed retreat. These results suggest a possible physical explanation for the abrupt retreat of glaciers in the Alps in the mid-19th century that is consistent with existing temperature and precipitation records and reconstructions.

  15. The Little Ice Age signature and subsequent warming seen in borehole temperature logs versus solar forcing model

    Czech Academy of Sciences Publication Activity Database

    Majorowicz, J.; Šafanda, Jan; Przybylak, R.


    Roč. 103, č. 4 (2014), s. 1163-1173 ISSN 1437-3254 Institutional support: RVO:67985530 Keywords : surface processes * borehole temperature s * climatic warming * Little Ice Age * solar irradiation Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.093, year: 2014

  16. Learning from Wisconsin (United States)

    Daniel, Jamie Owen


    Like thousands of other people from around the country and around the world, this author was heartened and inspired by the tenacity, immediacy, and creativity of the pushback by Wisconsin's public-sector unions against Governor Scott Walker's efforts to limit their collective bargaining rights. And like many others who made the trek to Madison to…

  17. Wisconsin's forest resources, 2010 (United States)

    C.H. Perry


    This publication provides an overview of forest resource attributes for Wisconsin based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report...

  18. Wisconsin's forest resources, 2005 (United States)

    Charles, H. (Hobie) Perry; Gary J. Brand


    The annual forest inventory of Wisconsin continues, and this document reports 2001-05 moving averages for most variables and comparisons between 2000 and 2005 for growth, removals, and mortality. Summary resource tables can be generated through the Forest Inventory Mapmaker website at htm. Estimates from this inventory show a...

  19. Wisconsin's forest resources, 2006 (United States)

    C.H. Perry; V.A. Everson


    Figure 2 was revised by the author in August 2008. This publication provides an overview of forest resource attributes for Wisconsin based on an annual inventory conducted by the Forest Inventory and Analysis program at the Northern Research Station of the U.S. Forest Service from 2002-2006. These estimates, along with associated core tables postedon the Internet, are...

  20. Wisconsin's Forest Resources, 2007 (United States)

    C.H. Perry; V.A. Everson


    This publication provides an overview of forest resource attributes for Wisconsin based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service, Northern Research Station. These estimates, along with web-posted core tables, are updated annually. For more information please refer to page 4 of this report.

  1. Wisconsin's forest resources, 2009 (United States)

    C.H. Perry


    This publication provides an overview of forest resource attributes for Wisconsin based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information, please refer to page 4 of this report...

  2. Carbon cycle instability as a cause of the late Pleistocene ice age oscillations - Modeling the asymmetric response (United States)

    Saltzman, Barry; Maasch, Kirk A.


    A dynamical model of the Pleistocene ice ages is presented, which incorporates many of the qualitative ideas advanced recently regarding the possible role of ocean circulation, chemistry, temperature, and productivity in regulating long-term atmospheric carbon dioxide variations. This model involves one additional term (and free parameter) beyond that included in a previous model (Saltzman and Sutera, 1987), providing the capacity for an asymmetric response. It is shown that many of the main features exhibited by the delta(O-18)-derived ice record and the Vostok core/delta(C-13)-derived carbon dioxide record in the late Pleistocene can be deduced as a free oscillatory solution of the model.

  3. Ice formation and development in aged, wintertime cumulus over the UK : observations and modelling (United States)

    Crawford, I.; Bower, K. N.; Choularton, T. W.; Dearden, C.; Crosier, J.; Westbrook, C.; Capes, G.; Coe, H.; Connolly, P.; Dorsey, J. R.; Gallagher, M. W.; Williams, P.; Trembath, J.; Cui, Z.; Blyth, A.


    In-situ high resolution aircraft measurements of cloud microphysical properties were made in coordination with ground based remote sensing observations of Radar and Lidar as part of the Aerosol Properties, PRocesses And InfluenceS on the Earth's climate (APPRAISE) project. A narrow but extensive line (~100 km long) of shallow convective clouds over the southern UK was studied. Cloud top temperatures were observed to be higher than ~-8 °C, but the clouds were seen to consist of supercooled droplets and varying concentrations of ice particles. No ice particles were observed to be falling into the cloud tops from above. Current parameterisations of ice nuclei (IN) numbers predict too few particles will be active as ice nuclei to account for ice particle concentrations at the observed near cloud top temperatures (~-7 °C). The role of biological particles, consistent with concentrations observed near the surface, acting as potential efficient high temperature IN is considered important in this case. It was found that very high concentrations of ice particles (up to 100 L-1) could be produced by powerful secondary ice particle production emphasising the importance of understanding primary ice formation in slightly supercooled clouds. Aircraft penetrations at -3.5 °C, showed peak ice crystal concentrations of up to 100 L-1 which together with the characteristic ice crystal habits observed (generally rimed ice particles and columns) suggested secondary ice production had occurred. To investigate whether the Hallett-Mossop (HM) secondary ice production process could account for these observations, ice splinter production rates were calculated. These calculated rates and observations could only be reconciled provided the constraint that only droplets >24 μm in diameter could lead to splinter production, was relaxed slightly by 2 μm. Model simulations of the case study were also performed with the WRF (Weather, Research and Forecasting) model and ACPIM (Aerosol Cloud and

  4. Simple energy balance model resolving the seasons and the continents - Application to the astronomical theory of the ice ages (United States)

    North, G. R.; Short, D. A.; Mengel, J. G.


    An analysis is undertaken of the properties of a one-level seasonal energy balance climate model having explicit, two-dimensional land-sea geography, where land and sea surfaces are strictly distinguished by the local thermal inertia employed and transport is governed by a smooth, latitude-dependent diffusion mechanism. Solutions of the seasonal cycle for the cases of both ice feedback exclusion and inclusion yield good agreements with real data, using minimal turning of the adjustable parameters. Discontinuous icecap growth is noted for both a solar constant that is lower by a few percent and a change of orbital elements to favor cool Northern Hemisphere summers. This discontinuous sensitivity is discussed in the context of the Milankovitch theory of the ice ages, and the associated branch structure is shown to be analogous to the 'small ice cap' instability of simpler models.

  5. Tracing the effects of the Little Ice Age in the tropical lowlands of eastern Mesoamerica. (United States)

    Lozano-García, Ma del Socorro; Caballero, Margarita; Ortega, Beatriz; Rodríguez, Alejandro; Sosa, Susana


    The causes of late-Holocene centennial to millennial scale climatic variability and the impact that such variability had on tropical ecosystems are still poorly understood. Here, we present a high-resolution, multiproxy record from lowland eastern Mesoamerica, studied to reconstruct climate and vegetation history during the last 2,000 years, in particular to evaluate the response of tropical vegetation to the cooling event of the Little Ice Age (LIA). Our data provide evidence that the densest tropical forest cover and the deepest lake of the last two millennia were coeval with the LIA, with two deep lake phases that follow the Spörer and Maunder minima in solar activity. The high tropical pollen accumulation rates limit LIA's winter cooling to a maximum of 2 degrees C. Tropical vegetation expansion during the LIA is best explained by a reduction in the extent of the dry season as a consequence of increased meridional flow leading to higher winter precipitation. These results highlight the importance of seasonal responses to climatic variability, a factor that could be of relevance when evaluating the impact of recent climate change.

  6. The Medieval Climate Anomaly and Little Ice Age in Chesapeake Bay and the North Atlantic Ocean (United States)

    Cronin, T. M.; Hayo, K.; Thunell, R.C.; Dwyer, G.S.; Saenger, C.; Willard, D.A.


    A new 2400-year paleoclimate reconstruction from Chesapeake Bay (CB) (eastern US) was compared to other paleoclimate records in the North Atlantic region to evaluate climate variability during the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA). Using Mg/Ca ratios from ostracodes and oxygen isotopes from benthic foraminifera as proxies for temperature and precipitation-driven estuarine hydrography, results show that warmest temperatures in CB reached 16-17. ??C between 600 and 950. CE (Common Era), centuries before the classic European Medieval Warm Period (950-1100. CE) and peak warming in the Nordic Seas (1000-1400. CE). A series of centennial warm/cool cycles began about 1000. CE with temperature minima of ~. 8 to 9. ??C about 1150, 1350, and 1650-1800. CE, and intervening warm periods (14-15. ??C) centered at 1200, 1400, 1500 and 1600. CE. Precipitation variability in the eastern US included multiple dry intervals from 600 to 1200. CE, which contrasts with wet medieval conditions in the Caribbean. The eastern US experienced a wet LIA between 1650 and 1800. CE when the Caribbean was relatively dry. Comparison of the CB record with other records shows that the MCA and LIA were characterized by regionally asynchronous warming and complex spatial patterns of precipitation, possibly related to ocean-atmosphere processes. ?? 2010.

  7. Conference Summary: First International Conference on Global Warming and the Next Ice Age (United States)

    Wetzel, Peter J.; Chylek, Petr; Lesins, Glen; Starr, David OC. (Technical Monitor)


    The First International Conference on Global Warming and the Next Ice Age was convened in Halifax, Nova Scotia, August 19-24, 2001. The conference program began each day with a 30 minute live classical music performances of truly international quality before the beginning business. Ample time for panel discussions was also scheduled. The general public was invited to attend and participate in a special evening panel session on the last day of the conference. The unusual and somewhat provocative title of the conference was designed to attract diverse views on global climate change. This summary attempts to accurately reflect the tone and flavor of the lively discussions which resulted. Presentations ranged from factors forcing current climate to those in effect across the span of time from the Proterozoic "snowball Earth" epoch to 50,000 years in the future. Although, as should be expected, attendees at the conference arrived with opinions on some of the controversial issues regarding climate change, and no-one openly admitted to a 'conversion' from their initial point of view, the interdisciplinary nature of the formal presentations, poster discussions, panels, and abundant informal discourse helped to place the attendees' personal perspectives into a broader, more diversified context.

  8. Global warming and ice ages: I. prospects for physics based modulation of global change

    Energy Technology Data Exchange (ETDEWEB)

    Teller, E.; Wood, L.; Hyde, R.


    It has been suggested that large-scale climate changes, mostly due to atmospheric injection of greenhouse gases connected with fossil-fired energy production, should be forestalled by internationally-agreed reductions in, e.g., electricity generation. The potential economic impacts of such limitations are obviously large: greater than or equal to $10{sup 11}/year. We propose that for far smaller - less than 1% - the mean thermal effects of greenhouse gases may be obviated in any of several distinct ways, some of them novel. These suggestions are all based on scatterers that prevent a small fraction of solar radiation from reaching all or part of the Earth. We propose research directed to quite near-term realization of one or more of these inexpensive approaches to cancel the effects of the greenhouse gas injection. While the magnitude of the climatic impact of greenhouse gases is currently uncertain, the prospect of severe failure of the climate, for instance at the onset of the next Ice Age, is undeniable. The proposals in this paper may lead to quite practical methods to reduce or eliminate all climate failures.

  9. The Maunder minimum and the Little Ice Age: an update from recent reconstructions and climate simulations (United States)

    Owens, Mathew J.; Lockwood, Mike; Hawkins, Ed; Usoskin, Ilya; Jones, Gareth S.; Barnard, Luke; Schurer, Andrew; Fasullo, John


    The Maunder minimum (MM) was a period of extremely low solar activity from approximately AD 1650 to 1715. In the solar physics literature, the MM is sometimes associated with a period of cooler global temperatures, referred to as the Little Ice Age (LIA), and thus taken as compelling evidence of a large, direct solar influence on climate. In this study, we bring together existing simulation and observational studies, particularly the most recent solar activity and paleoclimate reconstructions, to examine this relation. Using northern hemisphere surface air temperature reconstructions, the LIA can be most readily defined as an approximately 480 year period spanning AD 1440-1920, although not all of this period was notably cold. While the MM occurred within the much longer LIA period, the timing of the features are not suggestive of causation and should not, in isolation, be used as evidence of significant solar forcing of climate. Climate model simulations suggest multiple factors, particularly volcanic activity, were crucial for causing the cooler temperatures in the northern hemisphere during the LIA. A reduction in total solar irradiance likely contributed to the LIA at a level comparable to changing land use.

  10. Little Ice Age Wetting of Interior Asian Deserts and the Rise of the Mongol Empire (United States)

    Putnam, A. E.; Putnam, D.; Andreu-Hayles, L.; Cook, E. R.; Palmer, J. G.; Clark, E. H.; WANG, C.; Chen, F.; Denton, G.; Boyle, D. P.; Bassett, S.; Birkel, S. D.; Martin Fernandez, J.; Hajdas, I.; Southon, J. R.; Garner, C.; Broecker, W. S.


    Documenting hydrological responses to past climate changes may provide insights into how ongoing warming will alter the distribution of Earth's water resources. Here we report evidence suggesting that wetter-than-present conditions persisted during the past millennium in the deserts of the Tarim Basin, western China, located at the heart of Asia - Earth's largest and most populous continent. Our assessment is based on observations of landforms composed of waterlain sediments occurring throughout the Taklamakan and Lop Deserts of the Tarim Basin. These landforms are associated with subfossil phreatophyte trees, reeds, and mollusk shells. We applied 14C and dendrochronological dating techniques to construct a chronology for when the Tarim Basin was wetter than today. We also employed hydrological modeling to estimate plausible climatic conditions under which the observed wet environment could have been sustained. Our results indicate that the core of the Asian desert belt was dominantly wetter than today during the last major cold spell of the Holocene: The Little Ice Age. Wetter conditions in the Tarim Basin deserts accompanied northern cooling, snowline lowering, a strengthened boreal jet, and coeval weakening of south Asian monsoons. Southward migration of grasslands in response to wetter conditions may have aided the spread of the Mongol Empire across Asian drylands. On the other hand, net drying over the 20th century has led to drought that is unprecedented for at least the past ~830 years, and which could intensify with further warming.

  11. Global Warming and Ice Ages: I. Prospects For Physics Based Modulation of Global Change (United States)

    Teller, E.; Wood, L.; Hyde, R.


    It has been suggested that large-scale climate changes, mostly due to atmospheric injection of greenhouse gases connected with fossil-fired energy production, should be forestalled by internationally-agreed reductions in, e.g., electricity generation. The potential economic impacts of such limitations are obviously large: greater than or equal to $10{sup 11}/year. We propose that for far smaller - less than 1% - the mean thermal effects of greenhouse gases may be obviated in any of several distinct ways, some of them novel. These suggestions are all based on scatterers that prevent a small fraction of solar radiation from reaching all or part of the Earth. We propose research directed to quite near-term realization of one or more of these inexpensive approaches to cancel the effects of the greenhouse gas injection. While the magnitude of the climatic impact of greenhouse gases is currently uncertain, the prospect of severe failure of the climate, for instance at the onset of the next Ice Age, is undeniable. The proposals in this paper may lead to quite practical methods to reduce or eliminate all climate failures.

  12. Global warming and ice ages: I. prospects for physics- based modulation of global change

    International Nuclear Information System (INIS)

    Teller, E.; Wood, L.; Hyde, R.


    It has been suggested that large-scale climate changes, mostly due to atmospheric injection of greenhouse gases connected with fossil-fired energy production, should be forestalled by internationally-agreed reductions in, e.g., electricity generation. The potential economic impacts of such limitations are obviously large: greater than or equal to $10 11 /year. We propose that for far smaller - less than 1% - the mean thermal effects of greenhouse gases may be obviated in any of several distinct ways, some of them novel. These suggestions are all based on scatterers that prevent a small fraction of solar radiation from reaching all or part of the Earth. We propose research directed to quite near-term realization of one or more of these inexpensive approaches to cancel the effects of the greenhouse gas injection. While the magnitude of the climatic impact of greenhouse gases is currently uncertain, the prospect of severe failure of the climate, for instance at the onset of the next Ice Age, is undeniable. The proposals in this paper may lead to quite practical methods to reduce or eliminate all climate failures

  13. Wisconsin's Forests 2009 (United States)

    Charles H. Perry; Vern A. Everson; Brett J. Butler; Susan J. Crocker; Sally E. Dahir; Andrea L. Diss-Torrance; Grant M Domke; Dale D. Gormanson; Sarah K. Herrick; Steven S. Hubbard; Terry R. Mace; Patrick D. Miles; Mark D. Nelson; Richard B. Rodeout; Luke T. Saunders; Kirk M. Stueve; Barry T. Wilson; Christopher W. Woodall


    The second full annual inventory of Wisconsin's forests reports more than 16.7 million acres of forest land with an average volume of more than 1,400 cubic feet per acre. Forest land is dominated by the oak/hickory forest-type group, which occupies slightly more than one quarter of the total forest land area; the maple/beech/birch forest-type group occupies an...

  14. Historical reconstruction of storms in the West of France in the early Little Ice Age. (United States)

    Athimon, Emmanuelle; Maanan, Mohamed


    This research offers to : 1) identify, as accurately as possible, the storms and the coastal flooding in the early Little Ice Age, 2) expose their impacts on the environment and populations, 3) query the « resilience » and adaptation of medieval and modern coastal societies in the West of France by presenting their perceptions and reactions. The space-time frame of the study is located in France, from Brittany to Gascony, between the xivth and the xvith century. Sensitive and brittle, this area is regularly battered by violent winds. It also undergoes episodic sea flooding that can cause ruptures of balance. Hence, the historical reconstruction and analysis of storms and coastal flooding in a long period appear fundamental. A thorough knowledge of past meteo-marine hazards allows to recreate a link with the territory, particularly through the (re)construction of an effective memory of these phenomena. This process is essential however difficult because of many documentary gaps. They are due to historical contingencies such as wars, French Revolution, or archival disasters like the fire of the Chamber of Accounts in Paris in 1737. Many limits must also be taken into account and discussed as inaccurate dates, exaggerated or undervalued descriptions, strict spatial demarcation almost impossible to achieve for the xivth-xvith centuries. Furthermore, during this period, no death toll, material and economic balance was done after a climate disaster. Yet, many historical records - especially narrative sources, books of accounts or cities repairs - expose the impacts of storms and marine submersion on agriculture, environment, infrastructures, etc. For instance, a violent storm hit the coast on June 24th 1452. It washed away part of the roof of a castle on Noirmoutier island and knocked down the bell towers of two churches in Angers. Storms and sea flooding have affected activities, constructions and populations' lives. They have therefore forced societies to adapt


    Directory of Open Access Journals (Sweden)

    E. A. Zolotarev


    Full Text Available SummaryThe results of remote monitoring of the greatest inEuropemountain glaciation of Elbrus are covered for 120 years by instrumental survey (1887–2007 and lichenometric survey in 1986. The materials of stereoscopic digital photo survey of the whole glaciation with terrain resolution of2.5 metersproduced by space imaging system Cartosat-1 (IRS-P5 in 2007 were compared with the same year materials of phototheodolite survey of south glaciation slope (6 glaciers in total. Results of comparison showed that the data received from Cartosat-1 can be used for monitoring of glaciers with long enough interval of time between repeated surveys (from 10 years and more, and also is suitable for updating 1:25 000 topographic maps of mountain areas. The leading role of Dzhikiugankez plateau in changes was revealed. Over the last 50 years (1957–2007 the Dzhikiugankez share in change of the glaciation area as a whole has reached 45 %. The method of glacier dynamics research, based on digital technologies of image processing and assuming first of all visual deciphering of changes and in the second – measurement of parameters of changes is offered. The quantitative data of Elbrus glaciation reduction since the middle of the XIX century do not confirm the hypothesis of the global climate warming beginning just in the second half of XX century as a result of anthropogenic greenhouse gases effect. Contrarily in 1970s, many Elbrus glaciers advanced. Elbrus glaciation area reduction is occurring practically evenly through time and is alternated with short-term periods of stationary state and advance. These facts suggest that global climate warming, which alternated with short-term cooling periods, began after the end of the Little Ice Age and was most likely due to natural rather than anthropogenic causes.

  16. Glacier change in the Gangdise Mountains, southern Tibet, since the Little Ice Age (United States)

    Zhang, Qian; Yi, Chaolu; Fu, Ping; Wu, Yubin; Liu, Jinhua; Wang, Ninglian


    Delineating glacier change during the Little Ice Age (LIA) is of great importance when attempting to understand regional climatic changes and can also help to improve the understanding of any predictions of future glacial changes. However, such knowledge is still lacking for some critical regions of the Tibetan Plateau (TP). In this study, we mapped 4188 contemporary glaciers and reconstructed 1216 LIA areas of glacial coverage in the Gangdise Mountains to the north of the Himalaya using Google Earth satellite imagery. We estimated their paleoglacial areas and equilibrium line altitudes (ELAs) based on the toe-to-headwall altitude ratio (THAR) method. Results show that most glaciers are small (topographic conditions. The contemporary ELA ranges from 5516 to 6337 m asl; the LIA ELA ranged from 5476 to 6329 m asl. Contemporary and LIA ELA values rise from southeast to northwest. As a general rule, the rise in the ELA value decreases from the eastern to the central Gangdise Mountains and then increases westward, with a mean ELA rise of 45 m. Multiple regression models suggest that 46.8% of the glacier area loss can be explained by glacier elevation, area, and slope. However, only 15.5% of the rise in ELA values can be explained by glacial geometric, topographic, or locational parameters. The spatial pattern of modern ELA values in this region appears inversely related to precipitation, which decreases from southeast to northwest, implying that precipitation is one of the key controls of ELAs. This is also consistent with results from elsewhere in High Asia. In contrast to the Gangdise Mountains' eastern and western sectors, glaciers in the central sector have undergone less change, i.e., in terms of reductions in length, area loss, and rises in ELA. Topography can of course also influence glacial change by creating shielding and/or rainshadow effects and by affecting local temperatures.

  17. Exceptional Shift to a Weaker Atlantic Meridional Overturning Circulation at the end of the Little Ice Age (United States)

    Thornalley, D. J.; Oppo, D.; Moffa Sanchez, P.; Hall, I. R.; Keigwin, L. D.; Rose, N.; Green, K.; Pallottino, F.; Ortega, P.; Robson, J.


    Several proxy and modelling studies suggest that there may have been considerable change in the operation of the Atlantic Meridional Overturning Circulation (AMOC) during the last two millennia. Yet despite its importance for regional and global climate, the recent history of the AMOC is poorly constrained and comprehensive observational records only extend back a few decades at most. Observational data suggest that the export of large volumes of sea-ice and freshwater from the Arctic during the Great Salinity Anomaly of the late 1960s to early 1970s impacted North Atlantic circulation, and perhaps the strength of the AMOC, thus raising the possibility that more extreme events may have affected the AMOC during the pre-instrumental era. We present a suite of AMOC related proxies from high resolution marine sediment cores from the North Atlantic, spanning the last 2000 years, including proxies for both deep ocean circulation and surface ocean climate. Our results suggest that there was an exceptional shift to a weaker mode of Labrador Sea Water (LSW) formation during the late 19th century, which persisted up to the present day, notwithstanding strong decadal-scale LSW production events such as during the 1990s. Using a compilation of sites that allow the sea-surface temperature fingerprint of AMOC change to be identified, we show that the shift to weaker LSW formation was accompanied by a weakening of the combined AMOC. Preliminary data suggests that this exceptional event impacted marine ecosystems in certain locations. Based on their timing, we infer that the weakening of LSW and AMOC may have been caused by the export of sea-ice and freshwater from the Arctic during the termination of the Little Ice Age (somewhat mimicking, albeit on a smaller scale, the AMOC weakening events that accompanied the last Ice Age termination). These results have significant implications for the sensitivity of the AMOC to climate forcing, and the cause of late Holocene climate events.

  18. High Resolution Spatiotemporal Climate Reconstruction and Variability in East Asia during Little Ice Age (United States)

    Lin, K. H. E.; Wang, P. K.; Lee, S. Y.; Liao, Y. C.; Fan, I. C.; Liao, H. M.


    The Little ice Age (LIA) is one of the most prominent epochs in paleoclimate reconstruction of the Common Era. While the signals of LIA were generally discovered across hemispheres, wide arrays of regional variability were found, and the reconstructed anomalies were sometimes inconsistent across studies by using various proxy data or historical records. This inconsistency is mainly attributed to limited data coverage at fine resolution that can assist high-resolution climate reconstruction in the continuous spatiotemporal trends. Qing dynasty (1644-1911 CE) of China existed in the coldest period of LIA. Owing to a long-standing tradition that acquired local officials to record odds and social or meteorological events, thousands of local chronicles were left. Zhang eds. (2004) took two decades to compile all these meteorological records in a compendium, for which we then digitized and coded all records into our REACHS database system for reconstructing climate. There were in total 1,435 points (sites) in our database for over 80,000 events in the period of time. After implementing two-rounds coding check for data quality control (accuracy rate 87.2%), multiple indexes were retrieved for reconstructing annually and seasonally resolved temperature and precipitation series for North, Central, and South China. The reconstruction methods include frequency count and grading, with usage of multiple regression models to test sensitivity and to calculate correlations among several reconstructed series. Validation was also conducted through comparison with instrumental data and with other reconstructed series in previous studies. Major research results reveal interannual (3-5 years), decadal (8-12 years), and interdecadal (≈30 years) variabilities with strong regional expressions across East China. Cooling effect was not homogenously distributed in space and time. Flood and drought conditions frequently repeated but the spatiotemporal pattern was variant, indicating likely

  19. Modelling the behavior of the Jakobshavn glacier since the end of the Little Ice Age

    DEFF Research Database (Denmark)

    Muresan, Ioana Stefania; Khroulev, Constantine; Khan, Shfaqat Abbas


    Current model estimates of the Greenland Ice Sheet (GrIS) are almost entirely based on coarse grids (>10km) and constrained by climate models that span from 60s to present. To improve the projection of future sea level rise, a long-term data record that reveals the mass balance beyond decadal tim...

  20. Coupling between atmospheric CO2 and temperature during the onset of the Little Ice Age

    NARCIS (Netherlands)

    Hoof, T.B. van


    Present day global warming is primarily caused by the greenhouse effect of the increased CO2 emissions since the onset of the industrial revolution. A coupling between temperature and the greenhouse gas CO2 has also been observed in several ice-core records on a glacial-interglacial timescale as

  1. A refined TALDICE-1a age scale from 55 to 112 ka before present for the Talos Dome ice core based on high-resolution methane measurements

    Directory of Open Access Journals (Sweden)

    S. Schüpbach


    Full Text Available A precise synchronization of different climate records is indispensable for a correct dynamical interpretation of paleoclimatic data. A chronology for the TALDICE ice core from the Ross Sea sector of East Antarctica has recently been presented based on methane synchronization with Greenland and the EDC ice cores and δ18Oice synchronization with EDC in the bottom part (TALDICE-1. Using new high-resolution methane data obtained with a continuous flow analysis technique, we present a refined age scale for the age interval from 55–112 thousand years (ka before present, where TALDICE is synchronized with EDC. New and more precise tie points reduce the uncertainties of the age scale from up to 1900 yr in TALDICE-1 to below 1100 yr over most of the refined interval and shift the Talos Dome dating to significantly younger ages during the onset of Marine Isotope Stage 3. Thus, discussions of climate dynamics at sub-millennial time scales are now possible back to 110 ka, in particular during the inception of the last ice age. Calcium data of EDC and TALDICE are compared to show the impact of the refinement to the synchronization of the two ice cores not only for the gas but also for the ice age scale.

  2. Effect of ageing of K-feldspar on its ice nucleating efficiency in immersion, deposition and contact freezing modes (United States)

    Peckhaus, Andreas; Bachmann, Felix; Hoffmann, Nadine; Koch, Michael; Kiselev, Alexei; Leisner, Thomas


    Recently K-feldspar was identified as one of the most active atmospheric ice nucleating particles (INP) of mineral origin [1]. Seeking the explanation to this phenomena we have conducted extensive experimental investigation of the ice nucleating efficiency of K-feldspar in three heterogeneous freezing modes. The immersion freezing of K-feldspar was investigated with the cold stage using arrays of nanoliter-size droplets containing aqueous suspension of polydisperse feldspar particles. For contact freezing, the charged droplets of supercooled water were suspended in the laminar flow of the DMA-selected feldspar-containing particles, allowing for determination of freezing probability on a single particle-droplet contact [2]. The nucleation and growth of ice via vapor deposition on the crystalline surfaces of macroscopic feldspar particles have been investigated in the Environmental Scanning Electron Microscope (ESEM) under humidified nitrogen atmosphere. The ice nucleation experiments were supplemented with measurements of effective surface area of feldspar particles and ion chromatography (IC) analysis of the leached framework cations (K+, Na+, Ca2+, Mg2+). In this contribution we focus on the role of surface chemistry influencing the IN efficiency of K-feldspar, in particular the connection between the degree of surface hydroxylation and its ability to induce local structural ordering in the interfacial layer in water molecules (as suggested by recent modeling efforts). We mimic the natural process of feldspar ageing by suspending it in water or weak aqueous solution of carbonic acid for different time periods, from minutes to months, and present its freezing efficiency as a function of time. Our immersion freezing experiments show that ageing have a nonlinear effect on the freezing behavior of feldspar within the investigated temperature range (-40°C to -10°C). On the other hand, deposition nucleation of ice observed in the ESEM reveals clear different pattern

  3. Geographic and racial variation in teen pregnancy rates in Wisconsin. (United States)

    Layde, Molly M; Remington, Patrick L


    Despite recent declines in teen birth rates, teenage pregnancy remains an important public health problem in Wisconsin with significant social, economic, and health-related effects. Compare and contrast teen birth rate trends by race, ethnicity, and county in Wisconsin. Teen (ages 15-19 years) birth rates (per 1000 teenage females) in Wisconsin from 2001-2010 were compared by racelethnicity and county of residence using data from the Wisconsin Interactive Statistics on Health. Teen birth rates in Wisconsin have declined by 20% over the past decade, from 35.5/1000 teens in 2001 to 28.3/1000 teens in 2010-a relative decline of 20.3%. However, trends vary by race, with declines among blacks (-33%) and whites (-26%) and increases among American Indians (+21%) and Hispanics (+30%). Minority teen birth rates continue to be 3 to 5 times greater than birth rates among whites. Rates varied even more by county, with an over 14-fold difference between Ozaukee County (7.8/1000) and Menominee County (114.2). Despite recent declines, teen pregnancy continues to be an important public health problem in Wisconsin. Pregnancy prevention programs should be targeted toward the populations and counties with the highest rates.

  4. Glacier dynamics at Helheim and Kangerdlugssuaq glaciers, southeast Greenland, since the Little Ice Age

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas; Kjeldsen, Kristian Kjellerup; Kjær, Kurt H.


    Observations over the past decade show significant ice loss associated with the speed-up of glaciers in southeast Greenland from 2003, followed by a deceleration from 2006. These short-term, episodic, dynamic perturbations have a major impact on the mass balance on the decadal scale. To improve...... temperature to records of thickness and velocity change suggest that both glaciers are highly sensitive to short-term atmospheric and ocean forcing, and respond very quickly to small fluctuations. On century timescales, however, multiple external parameters (e.g. outlet glacier shape) may dominate the mass...... change. These findings suggest that special care must be taken in the projection of future dynamic ice loss....

  5. Long scale astronomical variations in our solar system: consequences for future ice ages

    International Nuclear Information System (INIS)

    Edvardsson, S.; Karlsson, K.G.


    It is well known that the Earth has gone through a number of glaciations during the last few million years. It is generally agreed that changes in the Earth's orbital parameters and obliquity play an important role in climate forcing, an idea originally due to Milutin Milankovitch. The climatic history of the Earth shows clear evidence of the precession periods (about 19 000 and 23 000 years) and changes in the obliquity (period about 41 000 years). The main period in glacial data (around 100 000 years) is, however, hard to explain in terms of orbital variations. During the last decade or so a large number of simulations of the planetary system have been reported, many of which have been concerned with the influence of variations in the Earth's orbit on climate. In former studies comparisons have been made between the astronomical parameters and the ice volume of the Earth. Generally speaking, the match between astronomical forcing and ice data has been rather poor. In this study we instead compare the parameters with changes in ice volume, which yields a much better agreement between the astronomical and the geological data. A number of climate models have been constructed to reproduce past climate history, and also to make predictions about the future. These are purely empirical models designed to match certain periods of past climate. Typically they also involve a substantial number of free parameters. (authors)

  6. Sr Isotopes at the Onset of the Ice Ages at the Northern Apennines (United States)

    Fuchs, Rita; Lazar, Boaz; Angiolini, Lucia; Crippa, Gaia; Stein, Mordechai


    Sr isotopes can be used to constrain the marine Sr budget. The temporal variations in the 87Sr/86Sr ratios (radiogenic Sr) have been reconstructed over the past few decades based on marine macro and micro fossils data (e.g. brachiopods and foraminifera). It is used to constrain the sources and amounts of strontium that dictate the temporal variations in oceanic Sr throughout the Phanerozoic. On the other hand, the study of processes controlling the composition stable Sr isotopes (δ88/86Sr) is very new and only limited research was conducted on this topic during the past few years. Up to date, no δ88/86Sr data are available for considerable parts of Earth's history and the contribution of the potential Sr sources to the oceans is poorly constrained. Here, we set to examine the behavior of radiogenic and stable Sr isotopes in the marine environment of the northern Apennines (Italy) during the time interval of the late Pliocene to early-Middle Pleistocene - upon the onset of ice ages in the northern latitudes. We collected fossil mollusks from outcrops of the Arda and Stirone Rivers that are rich in bivalves, brachiopods, foraminifera (that were used for establishing the chronostratigraphy of the sections) and other genera. Ecological and sedimentological analysis of the section suggest a normal marine environment of depth range of several tens of meters that existed on the southern flanks of the large Po embayment. In order to evaluate the potential of the fossil assemblages in the Arda and Stirone sections to serve as reliable recorders of the marine δ88/86Sr of seawater during the desired period, we examined mineralogical and chemical properties of the fossils (e.g. distribution of trace elements like Sr and Mg in the skeletons, microstructures like secondary fillings of punctate shells in brachiopod) and measured the 87Sr/86Sr ratios. Among the species analyzed, Aequipecten opercularis (bivalve) and Glycymeris inflata (bivalve) have aragonite skeletons that

  7. Tornadoes Strike Northern Wisconsin (United States)


    A series of tornadoes ripped through the Upper Midwest region of the United States in the evening of June 7, 2007. At least five different tornadoes touched down in Wisconsin, according to the Associated Press, one of which tore through the Bear Paw Resort in northern Wisconsin. Despite dropping as much as fifteen centimeters (six inches) of rain in some places and baseball-size hail in others, authorities were reporting no deaths attributable to the storm system, and only a smattering of injuries, but considerable property damage in some areas. When the MODIS instrument on NASA's Terra satellite observed the area on June 9, 2007, the track torn through the woods by one of the tornadoes stands out quite clearly. This photo-like image uses data collected by MODIS in the normal human vision range to give a familiar natural-looking appearance. The landscape is largely a checkerboard of farms, towns, roads, and cities. The pale land is predominantly farmland where crops have not fully grown in yet. Dark blue shows the winding path of rivers and lakes dotting the landscape. The large blue lake on the east (right) side of the image is Lake Michigan. Towns and cities, including the city of Green Bay, are gray. To the north side, farmland gives way to dark green as land use shifts from agriculture to the Menominee Indian Reservation and Nicolet National Forest. The diagonal slash through the dark green forested land shows the tornado track. Bare land was revealed where the tornado tore down trees or stripped vegetation off the branches. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions.

  8. Amazonian-aged fluvial system and associated ice-related features in Terra Cimmeria, Mars (United States)

    Adeli, Solmaz; Hauber, Ernst; Kleinhans, Maarten; Le Deit, Laetitia; Platz, Thomas; Fawdon, Peter; Jaumann, Ralf


    The Martian climate throughout the Amazonian is widely believed to have been cold and hyper-arid, very similar to the current conditions. However, ubiquitous evidence of aqueous and glacial activity has been recently reported, including channels that can be tens to hundreds of kilometres long, alluvial and fluvial deposits, ice-rich mantles, and glacial and periglacial landforms. Here we study a ∼340 km-long fluvial system located in the Terra Cimmeria region, in the southern mid-latitudes of Mars. The fluvial system is composed of an upstream catchment system with narrow glaciofluvial valleys and remnants of ice-rich deposits. We observe depositional features including fan-shaped deposits, and erosional features such as scour marks and streamlined islands. At the downstream section of this fluvial system is an outflow channel named Kārūn Valles, which displays a unique braided alluvial fan and terminates on the floor of the Ariadnes Colles basin. Our observations point to surface runoff of ice/snow melt as the water source for this fluvial activity. According to our crater size-frequency distribution analysis the entire fluvial system formed during early to middle Amazonian, between ∼ 1.8-0.2+0.2 Ga to 510-40+40 Ma. Hydraulic modelling indicates that the Kārūn Valles and consequently the alluvial fan formation took place in geologically short-term event(s). We conclude that liquid water was present in Terra Cimmeria during the early to middle Amazonian, and that Mars during that time may have undergone several episodic glacial-related events.

  9. Wisconsin SRF Electron Gun Commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Bisognano, Joseph J. [University of Wisconsin-Madison; Bissen, M. [University of Wisconsin-Madison; Bosch, R. [University of Wisconsin-Madison; Efremov, M. [University of Wisconsin-Madison; Eisert, D. [University of Wisconsin-Madison; Fisher, M. [University of Wisconsin-Madison; Green, M. [University of Wisconsin-Madison; Jacobs, K. [University of Wisconsin-Madison; Keil, R. [University of Wisconsin-Madison; Kleman, K. [University of Wisconsin-Madison; Rogers, G. [University of Wisconsin-Madison; Severson, M. [University of Wisconsin-Madison; Yavuz, D. D. [University of Wisconsin-Madison; Legg, Robert A. [JLAB; Bachimanchi, Ramakrishna [JLAB; Hovater, J. Curtis [JLAB; Plawski, Tomasz [JLAB; Powers, Thomas J. [JLAB


    The University of Wisconsin has completed fabrication and commissioning of a low frequency (199.6 MHz) superconducting electron gun based on a quarter wave resonator (QWR) cavity. Its concept was optimized to be the source for a CW free electron laser facility. The gun design includes active tuning and a high temperature superconducting solenoid. We will report on the status of the Wisconsin SRF electron gun program, including commissioning experience and first beam measurements.

  10. Wisconsin's forest resources in 2004 (United States)

    Charles H. Perry


    Results of the 2000-2004 annual inventory of Wisconsin show about 16.0 million acres of forest land, more than 22.1 billion cubic feet of live volume on forest land, and nearly 593 million dry tons of all live aboveground tree biomass on timberland. Populations of jack pine budworm are increasing, and it remains a significant pest in Wisconsin forests. A complete...

  11. Pleistocene population expansions of shade-tolerant trees indicate fragmentation of the African rainforest during the Ice Ages. (United States)

    Piñeiro, Rosalía; Dauby, Gilles; Kaymak, Esra; Hardy, Olivier J


    The fossil record in tropical Africa suggests that dry conditions during the Ice Ages caused expansion of savannahs and contraction of the rainforest. Forest refugia have been proposed to be located in areas of Central Africa that currently harbour high rates of endemic species. However, to what extent the forest was fragmented remains unknown. Nuclear microsatellites and plastid sequences of 732 trees of two species occurring in the same habitat-mature lowland evergreen rainforests-but with remarkably different dispersal capacities-animal versus gravity-were analysed. Geographical information system tools revealed intraspecific lineages partially congruent across the two species, suggesting common past barriers to gene flow in Central Africa. According to approximate Bayesian computation, the intraspecific genetic clusters diverged during the Pleistocene (less than 2 Ma), so that intraspecific differentiation is the appropriate scale to test the aridification effect of the Ice Ages on tree populations. Demographic tests revealed clear genetic signals of population expansion in both taxa, possibly following bottleneck events after forest fragmentation, with stronger evidence of expansion after the Penultimate rather than after the Last Glacial Maximum. The differential dispersal capacity may have modulated the particular response of each species to climate change, as revealed by the stronger evidence of expansion found in the animal-dispersed species than in the gravity-dispersed one. © 2017 The Author(s).

  12. Hydrogeology of southwestern Sheboygan County, Wisconsin, in the vicinity of the Kettle Moraine Springs fish hatchery (United States)

    Conlon, T.D.


    This report describes the hydrogeology of the dolomite aquifer of Silurian age and its relation to springs in a study area in southwestern Sheboygan County, Wisconsin. The study was conducted at the Kettle Moraine Springs fish hatchery in cooperation with the Wisconsin Department of Natural Resources.

  13. [Preliminary analysis of ginseng industry in Wisconsin]. (United States)

    Hu, Li; Zhang, Wen-sheng


    To study the case of Wisconsin as the top ginseng state in United States which has come through four developing steps: beginning, stagnating, flourishing and now, downturn. The current situation of the ginseng industry in Wisconsin was briefly introduced, the federal and state management on ginseng cultivation and export, the organization of Ginseng Board of Wisconsin and their marketing style based on the field investigation and data collected from USDA and Wisconsin state. The advantages and disadvantages of Wisconsin ginseng industry were analyzed in order to provide some suggestions for Chinese medicine industry. Chinese ginseng industry should learn the organization system from Wisconsin.

  14. Comparative Study of Probiotic Ice Cream and Probiotic Drink on Salivary Streptococcus mutans Levels in 6-12 Years Age Group Children. (United States)

    Mahantesha, Taranatha; Reddy, K M Parveen; Kumar, N H Praveen; Nara, Asha; Ashwin, Devasya; Buddiga, Vinutna


    Dental caries is one of the most common health problems in the world. Probiotics are one the various preventive methods to reduce dental caries. The aim of this study is to compare the effectiveness of probiotic ice cream and drink on salivary Streptococcus mutans levels in children of 6-12 years age group. A three phase study was carried out in children (n = 50) of 6-12 years age with zero decayed missing filled teeth (dmft)/DMFT. They were randomly divided into two equal groups. Saliva samples were collected before the consumptions of probiotic ice cream and probiotic drink. Colony count obtained was recorded as baseline data. For both groups probiotic ice cream and drink was given randomly for 7 days and a washout period of 90 days were given and then the saliva samples were collected and colony counting was done. Statistical analysis was performed using Student's paired t-test and multiple comparisons by Tukey's honest significant difference test which showed, there is a significant reduction in salivary S. mutans level in both groups after 7 days period. However, after washout period only probiotic ice cream showed reduction whereas drink did not. Also, there was no significant difference between probiotic ice cream and drink. Probiotic organisms definitely have a role in reducing the salivary S. mutans level and ice cream would be a better choice than drink. However, the prolonged use of the agents and their effects on caries is still to be determined.

  15. Cooling and societal change during the Late Antique Little Ice Age from 536 to around 660 AD (United States)

    Büntgen, Ulf; Myglan, Vladimir S.; Ljungqvist, Fredrik Charpentier; McCormick, Michael; di Cosmo, Nicola; Sigl, Michael; Jungclaus, Johann; Wagner, Sebastian; Krusic, Paul J.; Esper, Jan; Kaplan, Jed O.; de Vaan, Michiel A. C.; Luterbacher, Jürg; Wacker, Lukas; Tegel, Willy; Kirdyanov, Alexander V.


    Climatic changes during the first half of the Common Era have been suggested to play a role in societal reorganizations in Europe and Asia. In particular, the sixth century coincides with rising and falling civilizations, pandemics, human migration and political turmoil. Our understanding of the magnitude and spatial extent as well as the possible causes and concurrences of climate change during this period is, however, still limited. Here we use tree-ring chronologies from the Russian Altai and European Alps to reconstruct summer temperatures over the past two millennia. We find an unprecedented, long-lasting and spatially synchronized cooling following a cluster of large volcanic eruptions in 536, 540 and 547 AD (ref. ), which was probably sustained by ocean and sea-ice feedbacks, as well as a solar minimum. We thus identify the interval from 536 to about 660 AD as the Late Antique Little Ice Age. Spanning most of the Northern Hemisphere, we suggest that this cold phase be considered as an additional environmental factor contributing to the establishment of the Justinian plague, transformation of the eastern Roman Empire and collapse of the Sasanian Empire, movements out of the Asian steppe and Arabian Peninsula, spread of Slavic-speaking peoples and political upheavals in China.

  16. Impact of Wisconsin Medicaid Policy Change on Dental Sealant Utilization. (United States)

    Okunseri, Christopher; Okunseri, Elaye; Garcia, Raul I; Gonzalez, Cesar; Visotcky, Alexis; Szabo, Aniko


    In September 2006, Wisconsin Medicaid changed its policy to allow nondentists to become certified Medicaid providers and to bill for sealants in public health settings. This study examined changes in patterns of dental sealant utilization in first molars of Wisconsin Medicaid enrollees associated with a policy change. The Electronic Data Systems of Medicaid Evaluation and Decision Support for Wisconsin from 2001 to 2009. Retrospective claims data analysis of Wisconsin Dental Medicaid for children aged 6-16 years. A total of 479,847 children followed up for 1,441,300 person-years with 64,546 visits were analyzed. The rate of visits for sealants by dentists increased significantly from 3 percent per year prepolicy to 11 percent per year postpolicy, and that of nondentists increased from 18 percent per year to 20 percent after the policy change, but this was not significant. Non-Hispanic blacks had the lowest visit rates for sealant application by dentists and nondentists pre- and postpolicy periods. The Wisconsin Medicaid policy change was associated with increased rates of visits for dental sealant placement by dentists. The rate of visits with sealant placements by nondentists increased at the same rate pre- and postpolicy change. © Health Research and Educational Trust.

  17. An investigation into the use of color as a device to convey memes during the Little Ice Age (United States)

    White, Peter A.

    Color is used as a tool in visual communication to express ideas in a symbolic fashion. It can also be used as a guide to assist the viewer in the visual narrative. Artwork created in the period of time between 1300 to 1850 in northern and central Europe provides a comprehensive perspective in the use of color as symbol and color as an elucidative devise. This period of time is known as the Little Ice Age, the duration of which spans European history between the Medieval period and the Romantic era. The extreme climatic conditions of this era caused profound changes in society on many levels and influenced the use of color in paintings throughout this chapter in history. The new paradigm of the science of ideas, called memetics, provides a framework to analyze the expression of ideas through the use of color within this span of time.

  18. The onset of the Little Ice Age in Andalusia (southern Spain: detection and characterization from documentary sources

    Directory of Open Access Journals (Sweden)

    F. S. Rodrigo

    Full Text Available In this work the onset of the "Little Ice Age" period in Andalusia (southern Spain is analysed from documentary data, focusing attention on the evolution of the climate during the 16th and 17th centuries. It is shown that changes in the rainfall regime have been more important than those in the temperature in studying the Andalusian climate change. Analysis of the total annual precipitation is carried out by codifying the documentary data and establishing an ordinal index. Several statistical methods are used to detect and characterize climate changes in the region. The results suggest a fluctuating evolution, without trends or abrupt changes, with a prevailing wet period from 1550 to 1650 AD. Cycles of ~17, 3.5 and 2.1 years are detected. Some possible causal mechanisms are suggested.

  19. The onset of the Little Ice Age in Andalusia (southern Spain: detection and characterization from documentary sources

    Directory of Open Access Journals (Sweden)

    F. S. Rodrigo


    Full Text Available In this work the onset of the "Little Ice Age" period in Andalusia (southern Spain is analysed from documentary data, focusing attention on the evolution of the climate during the 16th and 17th centuries. It is shown that changes in the rainfall regime have been more important than those in the temperature in studying the Andalusian climate change. Analysis of the total annual precipitation is carried out by codifying the documentary data and establishing an ordinal index. Several statistical methods are used to detect and characterize climate changes in the region. The results suggest a fluctuating evolution, without trends or abrupt changes, with a prevailing wet period from 1550 to 1650 AD. Cycles of ~17, 3.5 and 2.1 years are detected. Some possible causal mechanisms are suggested.

  20. Timing of the Late Paleozoic Ice Age: A Review of the Status Quo and New U-Pb Zircon Ages From Southern Gondwana (United States)

    Mundil, R.; Griffis, N. P.; Keller, C. B.; Fedorchuk, N.; Montanez, I. P.; Isbell, J.; Vesely, F.; Iannuzzi, R.


    Throughout the Carboniferous and Permian Late Paleozoic Ice Age (LPIA), glaciations in southern Gondwana exerted a profound influence on global climate and environment, ocean chemistry, and the nature of sedimentary processes. The LPIA is widely regarded as an analogue for Pleistocene glaciations. Our understanding of the latter, as well as the validity of predictions for the future global climate and environment, depends therefore on our ability to reconstruct the LPIA. A robust chronostratigraphic framework built on high precision/high accuracy geochronology is crucial for the reconstruction of events and processes that occurred during the LPIA, particularly in the absence of high-resolution terrestrial biostratigraphic constraints that apply to both near- and far-field proxy records. The occurrence of volcaniclastic layers containing primary volcanic zircon at many levels throughout southern Gondwana makes such a reconstruction feasible, but complications inevitably arise due to the mixing of older age components with primary volcanic crystals, as well as the potential of unrecognized open system behavior to produce spurious younger ages. These pitfalls cause age dispersion that may be difficult to interpret, or is unrecognized if low precision geochronological techniques are used, resulting in inaccurate radioisotopic ages. Our current efforts in the Parana Basin (Southern Brazil) and the Karoo Basin (South Africa/Namibia) concentrate on building a robust and exportable chronostratigraphic framework based on U-Pb zircon CA-TIMS ages with sub-permil level precision combined with Bayesian approaches for resolving the eruption age of dispersed age spectra to facilitate the reconstruction of glaciogenic processes through the Carboniferous-Permian transition, as well as their implications for global sea level, atmospheric pCO2 and ocean chemistry. We will also review currently available geochronological data from contemporaneous Australian successions and their

  1. Little Ice Age climate reconstruction from ensemble reanalysis of Alpine glacier fluctuations

    Directory of Open Access Journals (Sweden)

    M. P. Lüthi


    Full Text Available Mountain glaciers sample a combination of climate fields – temperature, precipitation and radiation – by accumulation and melting of ice. Flow dynamics acts as a transfer function that maps volume changes to a length response of the glacier terminus. Long histories of terminus positions have been assembled for several glaciers in the Alps. Here I analyze terminus position histories from an ensemble of seven glaciers in the Alps with a macroscopic model of glacier dynamics to derive a history of glacier equilibrium line altitude (ELA for the time span 400–2010 C.E. The resulting climatic reconstruction depends only on records of glacier variations. The reconstructed ELA history is similar to recent reconstructions of Alpine summer temperature and Atlantic Multidecadal Oscillation (AMO index, but bears little resemblance to reconstructed precipitation variations. Most reconstructed low-ELA periods coincide with large explosive volcano eruptions, hinting at a direct effect of volcanic radiative cooling on mass balance. The glacier advances during the LIA, and the retreat after 1860, can thus be mainly attributed to temperature and volcanic radiative cooling.

  2. Molecular evidence of the survival of subterranean amphipods (Arthropoda) during Ice Age underneath glaciers in Iceland. (United States)

    Kornobis, Etienne; Pálsson, Snaebjörn; Kristjánsson, Bjarni K; Svavarsson, Jörundur


    A Two endemic groundwater arthropod crustacean species, Crangonyx islandicus and Crymostygius thingvallensis, were recently discovered on the mid-Atlantic volcanic island of Iceland. The extent of morphological differences from closest relatives, endemism, along with the geographic isolation of Iceland and its complete coverage by glaciers 21,000 years ago, suggests that these two species have survived glaciation periods in sub-glacial refugia. Here we provide strong support for this hypothesis by an analysis of mitochondrial genetic variation within Crangonyx islandicus. Our results show that the species is divided into several distinct monophyletic groups that are found along the volcanic zone in Iceland, which have been separated by 0.5 to around 5 million years. The genetic divergence between groups reflects geographic distances between sampling sites, indicating that divergence occurred after the colonization of Iceland. The genetic patterns, as well as the dependency of genetic variation on distances from the tectonic plate boundary and altitude, points to recent expansion from several refugia within Iceland. This presents the first genetic evidence of multicellular organisms as complex as crustacean amphipods which have survived glaciations beneath an ice sheet. This survival may be explained by geothermal heat linked to volcanic activities, which may have maintained favourable habitats in fissures along the tectonic plate boundary in Iceland during glaciations.

  3. Preservation of Late Amazonian Mars ice and water-related deposits in a unique crater environment in Noachis Terra: Age relationships between lobate debris tongues and gullies (United States)

    Morgan, Gareth A.; Head, James W.; Marchant, David R.


    The Amazonian period of Mars has been described as static, cold, and dry. Recent analysis of high-resolution imagery of equatorial and mid-latitude regions has revealed an array of young landforms produced in association with ice and liquid water; because near-surface ice in these regions is currently unstable, these ice-and-water-related landforms suggest one or more episodes of martian climate change during the Amazonian. Here we report on the origin and evolution of valley systems within a degraded crater in Noachis Terra, Asimov Crater. The valleys have produced a unique environment in which to study the geomorphic signals of Amazonian climate change. New high-resolution images reveal Hesperian-aged layered basalt with distinctive columnar jointing capping interior crater fill and providing debris, via mass wasting, for the surrounding annular valleys. The occurrence of steep slopes (>20°), relatively narrow (sheltered) valleys, and a source of debris have provided favorable conditions for the preservation of shallow-ice deposits. Detailed mapping reveals morphological evidence for viscous ice flow, in the form of several lobate debris tongues (LDT). Superimposed on LDT are a series of fresh-appearing gullies, with typical alcove, channel, and fan morphologies. The shift from ice-rich viscous-flow formation to gully erosion is best explained as a shift in martian climate, from one compatible with excess snowfall and flow of ice-rich deposits, to one consistent with minor snow and gully formation. Available dating suggests that the climate transition occurred >8 Ma, prior to the formation of other small-scale ice-rich flow features identified elsewhere on Mars that have been interpreted to have formed during the most recent phases of high obliquity. Taken together, these older deposits suggest that multiple climatic shifts have occurred over the last tens of millions of years of martian history.

  4. Regional reconstruction of subglacial hydrology and glaciodynamic behaviour along the southern margin of the Cordilleran Ice Sheet in British Columbia, Canada and northern Washington State, USA (United States)

    Lesemann, Jerome-Etienne; Brennand, Tracy A.


    Subglacial landsystems in and around Okanagan Valley, British Columbia, Canada are investigated in order to evaluate landscape development, subglacial hydrology and Cordilleran Ice Sheet dynamics along its southern margin. Major landscape elements include drumlin swarms and tunnel valleys. Drumlins are composed of bedrock, diamicton and glaciofluvial sediments; their form truncates the substrate. Tunnel valleys of various scales (km to 100s km length), incised into bedrock and sediment, exhibit convex longitudinal profiles, and truncate drumlin swarms. Okanagan Valley is the largest tunnel valley in the area and is eroded >300 m below sea level. Over 600 m of Late Wisconsin-age sediments, consisting of a fining-up sequence of cobble gravel, sand and silt fill Okanagan Valley. Landform-substrate relationships, landform associations, and sedimentary sequences are incompatible with prevailing explanations of landsystem development centred mainly on deforming beds. They are best explained by meltwater erosion and deposition during ice sheet underbursts. During the Late-Wisconsin glaciation, Okanagan Valley functioned as part of a subglacial lake spanning multiple connected valleys (few 100s km) of southern British Columbia. Subglacial lake development started either as glaciers advanced over a pre-existing sub-aerial lake (catch lake) or by incremental production and storage of basal meltwater. High geothermal heat flux, geothermal springs and/or subglacial volcanic eruptions contributed to ice melt, and may have triggered, along with priming from supraglacial lakes, subglacial lake drainage. During the underburst(s), sheetflows eroded drumlins in corridors and channelized flows eroded tunnel valleys. Progressive flow channelization focused flows toward major bedrock valleys. In Okanagan Valley, most of the pre-glacial and early-glacial sediment fill was removed. A fining-up sequence of boulder gravel and sand was deposited during waning stages of the underburst(s) and

  5. Using AMS to Help Interpret Glaciogenic Deposits of the Late Paleozoic Ice Age in the Parana Basin, Brazil (United States)

    Amato, James Anthony

    The term 'diamictite' is used as a lithologic descriptive term without assigning a particular origin to a rock unit as either glacial deposits (till), proglacial, glacially influenced deposits (resulting from meltwater plumes and ice rafted debris), or mass transport deposits (glacial or non-glacial related). While in some cases, it is possible to delineate between the origins of diamictites, in other instances, weathering and lack of exposures make it difficult to determine. In general, the occurrence of diamictites within the Gondwana succession has been traditionally used to indicate the occurrence of subglacial deposition despite the potential occurrence of other depositional modes. Thus, the extent of glaciation during the Late Paleozoic Ice Age is interpreted to be much greater than it actually was. . One area of interest in Gondwana where interpretation of these deposits is problematic, and hence has resulted in problems determining ice extent, is the Parana Basin in Brazil. The ability to better differentiate subglacial processes from proglacial, subaqueous mass transport, glaciomarine/glaciolacustrine rainout, and/or ice rafting, in addition to determining glacier flow or mass transport directions, will allow researchers studying these deposits to more accurately reconstruct the environments timing and extent of glaciation during the LPIA. In sedimentary fabrics, anisotropy of magnetic susceptibility (AMS) is a geophysical method, which depicts the preferred orientation of magnetic particles during the final stages of transport and/or synsedimentary deformation. The technique is used to determine the preferred orientation of the constituent grains, therefore a useful indicator to help determine the mode of deposition, direction of sediment transport, and the nature of stress and strain during deformation. In August of 2016, samples were collected from deposits assigned to the Itarare Group, which outcrop along the southern and eastern margins of the Parana

  6. Residential Energy Efficiency Potential: Wisconsin

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)


    Energy used by Wisconsin single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  7. Wisconsin's fourth forest inventory, 1983. (United States)

    John S. Jr. Spencer; W. Brad Smith; Jerold T. Hahn; Gerhard K. Raile


    The fourth inventory of the timber resource of Wisconsin shows that growing-stock volume increased from 11.2 to 15.5 billion cubic feet between 1968 and 1983, and area of timberland increased from 14.5 to 14.8 million acres. Presented are analysis and statistics on forest area and timber volume, growth, mortality, removals, and projections.

  8. Wisconsin's forest resources in 2001. (United States)

    John S. Vissage; Gery J. Brand; Manfred E. Mielke


    Results of the 2001 annual inventory of Wisconsin show about 15.8 million acres of forest land, more than 21.6 billion cubic feet of live volume on forest land, and nearly 584 million dry tons of all live aboveground tree biomass on timberland. Gypsy moth, forest tent caterpillar, twolined chestnut borer, bronze birch borer, ash yellows, and white pine blister rust...

  9. Educational Attainment in Southeast Wisconsin (United States)

    Million, Laura; Henken, Rob; Dickman, Anneliese


    In metro Milwaukee, as a part of the WIRED Initiative, the Regional Workforce Alliance (RWA)--a collaboration of organizations representing workforce development, economic development and education across southeast Wisconsin--has established the framework for pursuing the local talent dividend goal and a regional strategy for increasing…

  10. Birds of Prey of Wisconsin. (United States)

    Hamerstrom, Frances

    This copiously illustrated document is designed to be a field quide to birds of prey that are common to Wisconsin, as well as to some that enter the state occasionally. An introduction discusses birds of prey with regard to migration patterns, the relationship between common names and the attitudes of people toward certain birds, and natural signs…

  11. Glacier History of the Northern Antarctic Peninsula Region Since the End of the Last Ice Age and Implications for Southern Hemisphere Westerly-Climate Changes (United States)

    Kaplan, M. R.; Schaefer, J. M.; Strelin, J. A.; Peltier, C.; Southon, J. R.; Lepper, K. E.; Winckler, G.


    For the area around James Ross Island, we present new cosmogenic 10Be exposure ages on glacial deposits, and 14C ages on associated fossil materials. These data allow us to reconstruct in detail when and how the Antarctic Peninsula Ice Sheet retreated around the Island as the last Ice Age ended, and afterward when local land-based glaciers fluctuated. Similar to other studies, we found widespread deglaciation during the earliest Holocene, with fjords and bays becoming ice free between about 11,000 and 8,000 years ago. After 7,000 years ago, neoglacial type advances initiated. Then, both expansions and ice free periods occurred from the middle to late Holocene. We compare the new glacier record to those in southern Patagonia, which is on the other side of the Drake Passage, and published Southern Ocean marine records, in order to infer past middle to high latitude changes in the Southern Hemisphere Westerlies. Widespread warmth in the earliest Holocene, to the north and south of the Drake Passage, led to small glacier systems in Patagonia and wide-ranging glacier recession around the northern Antarctic Peninsula. We infer that this early Holocene period of overall glacier recession - from Patagonia to the northern Peninsula - was caused by a persistent far-southerly setting of the westerlies and accompanying warm climates. Subsequently, during the middle Holocene renewed glacier expansions occurred on both sides of the Drake Passage, which reflects that the Westerlies and associated colder climate systems were generally more equatorward. From the middle to late Holocene, glacier expansions and ice free periods (and likely related ice shelf behavior) document how the Westerlies and associated higher-latitude climate systems varied.

  12. Coach Selections and the Relative Age Effect in Male Youth Ice Hockey (United States)

    Hancock, David J.; Ste-Marie, Diane M.; Young, Bradley W.


    Relative age effects (RAEs; when relatively older children possess participation and performance advantages over relatively younger children) are frequent in male team sports. One possible explanation is that coaches select players based on physical attributes, which are more likely witnessed in relatively older athletes. Purpose: To determine if…

  13. Global Glacial Isostasy and the Surface of the Ice-Age Earth: The ICE-5G (VM2) Model and GRACE (United States)

    Peltier, W. R.


    The 100 kyr quasiperiodic variation of continental ice cover, which has been a persistent feature of climate system evolution throughout the most recent 900 kyr of Earth history, has occurred as a consequence of changes in the seasonal insolation regime forced by the influence of gravitational n-body effects in the Solar System on the geometry of Earth's orbit around the Sun. The impacts of the changing surface ice load upon both Earth's shape and gravitational field, as well as upon sea-level history, have come to be measurable using a variety of geological and geophysical techniques. These observations are invertible to obtain useful information on both the internal viscoelastic structure of the solid Earth and on the detailed spatiotemporal characteristics of glaciation history. This review focuses upon the most recent advances that have been achieved in each of these areas, advances that have proven to be central to the construction of the refined model of the global process of glacial isostatic adjustment, denoted ICE-5G (VM2). A significant test of this new global model will be provided by the global measurement of the time dependence of the gravity field of the planet that will be delivered by the GRACE satellite system that is now in space.

  14. Glacial recession in the Tropical Andes from the Little Ice Age: the case of Ampato Volcanic Complex (Southern Peru (United States)

    Alcalá, J.; Palacios, D.; Zamorano, J. J.


    Data published over the last decade reveal substantial glacial recession in the tropical Andes since the Little Ice Age (LIA), (Ramirez, et al., 2001; Rabatel, et al., 2005; Rabatel, et al., 2008; Vuille, et al., 2008; Hastenrath, 2009; Jomelli, et al., 2009), and a growing rate of recession since the 1980’s caused by global warming (Ramirez, et al., 2001; Vuille, et al., 2008). Today there is great interest in the evolution of these ice masses due to heightened awareness of climate change and of the strategic importance that glaciers have as a hydrologic resource for communities in arid climate zones in the tropical Andes (Mark, 2008; Vuille et al., 2008). Cordillera Blanca forms part of the Andes Mountains of northern Peru, and is a chosen site for many studies on glacier evolution. Vuille et al. 2008 determined that a considerable area of ice mass was lost at Huascarán-Chopicalqui glacier (18% from 1920-1970) and Astesonraju glacier (20% from 1962-2003). Studies at Coropuna volcano, which has the most extensive glacier field in the western range of southern Peru, also report a strong melting trend that began with only minimal recession from 1955-1986 (4%), but increased to 14% from 1986-2007 (Úbeda et al., 2009). Only a few of the Andes glaciers are consistently monitored, and the most comprehensive data are for Chacaltaya and Zongo glaciers (16º S) in Bolivia. Since the maximum LIA, Chacaltaya has lost 89% of its surface area, particularly in recent years. By 1983, the totaled loss was five times the shrinkage for the period 1940-1963 (Ramirez, et al., 2001). Zongo glacier maintained equilibrium from 1956-1975, but later experienced a period dominated by continuous recession (Soruco, et al., 2009). This study expands current knowledge of glacier evolution since the LIA in the Central Volcanic Zone (CVZ; 14º - 27º S) (Stern, 2004) of the Andes. The study site was chosen in an area that had never been used for preliminary research of this type, concretely

  15. UV–Vis Light-induced Aging of Titan’s Haze and Ice (United States)

    Couturier-Tamburelli, Isabelle; Piétri, Nathalie; Le Letty, Vincent; Chiavassa, Thierry; Gudipati, Murthy


    The study of the photochemical aging of aerosols is an important tool for understanding Titan’s stratosphere/troposphere composition and evolution, particularly the haze. Laboratory simulations of the photoreactivity of the haze aerosol analogs provide insight into the photochemical evolution of Titan’s atmosphere at and below the haze layers. Here we use experimental simulations to investigate the evolution of the laboratory analogs of these organic aerosols under ultraviolet (UV)–visible (Vis) photons, which make it through the haze layers during their sedimentation process. We present experimental results for the aging of Titan’s aerosol analogs obtained from two dominant nitrogen-containing organics, HC3N and HCN, under simulated Titan atmospheric conditions (photons and temperature). We report that volatile nitriles condensed on haze particles could be incorporated through photochemistry and provide one such sink mechanism for nitrile compounds. We provide laboratory evidence that the organic aerosols could photochemically evolve during their sedimentation through Titan’s atmosphere.

  16. Water resources of Wisconsin: lower Wisconsin River basin (United States)

    Hindall, S.M.; Borman, Ronald G.


    This report describes the physical environment, availability, distribution, movement, quality, and use of water in the upper Wisconsin River basin as an aid in planning and water management. The report presents general information on the basin derived from data obtained from Federal, State, and local agencies, New field data were collected in areas where information was lacking. More detailed studies of problem areas may be required in the future, as water needs and related development increase.

  17. Vegetation response to southern California drought during the Medieval Climate Anomaly and early Little Ice Age (AD 800–1600) (United States)

    Heusser, Linda E.; Hendy, Ingrid L.; Barron, John A.


    High-resolution studies of pollen in laminated sediments deposited in Santa Barbara Basin (SBB) core SPR0901-02KC reflect decadal-scale fluctuations in precipitation spanning the interval from AD 800–1600. From AD 800–1090 during the Medieval Climate Anomaly (MCA) SBB sediments were dominated by xeric vegetation types (drought-resistant coastal sagebrush and chaparral) implying reduced precipitation in the southern California region. Drought-adapted vegetation abruptly decreased at AD 1090 and was rapidly replaced by mesic oak (Quercus) woodlands associated with an increased pollen flux into the basin. After a mesic interval lasting ∼100 years, pollen flux and the relative abundance of Quercus pollen dropped abruptly at AD 1200 when the rapid rise of chaparral suggests a significant drought similar to that of the MCA (∼AD 800–1090). This brief resurgence of drought-adapted vegetation between AD 1200–1270 marked the end of the MCA droughts. A gradual increase in mesic vegetation followed, characterizing cool hydroclimates of the Little Ice Age (LIA) in coastal southern California.

  18. Seasonal variability in Northern Hemisphere atmospheric circulation during the Medieval Climate Anomaly and the Little Ice Age (United States)

    Edwards, Thomas W. D.; Hammarlund, Dan; Newton, Brandi W.; Sjolte, Jesper; Linderson, Hans; Sturm, Christophe; St. Amour, Natalie A.; Bailey, Joscelyn N.-L.; Nilsson, Anders L.


    Here we report new reconstructions of winter temperature and summer moisture during the past millennium in southeastern Sweden, based on stable-isotope data from a composite tree-ring sequence, that further enhances our knowledge and understanding of seasonal climate variability in the Northern Hemisphere over the past millennium. Key features of these new climate proxy records include evidence for distinctive fluctuations in winter temperature in SE Sweden, superimposed upon the general pattern of cooling between the so-called Medieval Climate Anomaly (MCA) of the early millennium and the Little Ice Age (LIA) of the late millennium, as well as evidence for sustained summer wetness during the MCA, followed by drier and less variable conditions during the LIA. We also explore these new records within a circumpolar spatial context by employing self-organizing map analysis of meteorological reanalysis data to identify potential modern analogues of mid-tropospheric synoptic circulation types in the Northern Hemisphere extratropics that can reconcile varying seasonal climate states during the MCA and LIA in SE Sweden with less variable conditions in southwestern Canada, as portrayed by paleoclimate records developed in the same manner in an earlier study.

  19. Climatic variability in the Gulf of California associated with the Medieval Warm Period and the Little Ice Age (United States)

    Flores-Castillo, O. D. L. A.; Martínez-López, A.; Perez-Cruz, L. L.


    Marine ecosystems close to the coasts are highly susceptible to be affected both by the variability due to natural processes of the climate system as well as by anthropogenic activities. The Gulf of California, located near the tropical Pacific region, whose influence on the long-term global climate has already been demonstrated, represents a great opportunity to assess the regional response to these effects. This study reconstructs some of the oceanographic and climatic conditions that occurred simultaneously with the Medieval Warm Period (MWP) and the Little Ice Age (LIA) climatic periods in the southern region of the gulf. This reconstruction was based on the use of multiple indirect indicators or proxies of paleoproduction and geochemistry (determined by isotope-ratios mass spectrometer interfaced with an elemental analyzer and inductively coupled plasma mass spectrometry) preserved in a high-resolution laminated sedimentary sequence collected in the slope of southeastern coast of the Gulf of California (24.2822 ° N and 108.3037 ° W). The main effects of these periods were higher precipitation conditions that generated a greater fluvial contribution during the MWP besides a bigger oxygenation of the water mass near the bottom. These conditions were followed by an increase in exported production, decrease in the oxygen content of the water near the bottom and an increase in the denitrification during the transition to the LIA. The results confirm the existence of oceanographic and climatic variability on a secular scale in the Gulf of California associated with both global climatic periods.

  20. Seasonal modulation of the Asian summer monsoon between the Medieval Warm Period and Little Ice Age: a multi model study (United States)

    Kamae, Youichi; Kawana, Toshi; Oshiro, Megumi; Ueda, Hiroaki


    Instrumental and proxy records indicate remarkable global climate variability over the last millennium, influenced by solar irradiance, Earth's orbital parameters, volcanic eruptions and human activities. Numerical model simulations and proxy data suggest an enhanced Asian summer monsoon during the Medieval Warm Period (MWP) compared to the Little Ice Age (LIA). Using multiple climate model simulations, we show that anomalous seasonal insolation over the Northern Hemisphere due to a long cycle of orbital parameters results in a modulation of the Asian summer monsoon transition between the MWP and LIA. Ten climate model simulations prescribing historical radiative forcing that includes orbital parameters consistently reproduce an enhanced MWP Asian monsoon in late summer and a weakened monsoon in early summer. Weakened, then enhanced Northern Hemisphere insolation before and after June leads to a seasonally asymmetric temperature response over the Eurasian continent, resulting in a seasonal reversal of the signs of MWP-LIA anomalies in land-sea thermal contrast, atmospheric circulation, and rainfall from early to late summer. This seasonal asymmetry in monsoon response is consistently found among the different climate models and is reproduced by an idealized model simulation forced solely by orbital parameters. The results of this study indicate that slow variation in the Earth's orbital parameters contributes to centennial variability in the Asian monsoon transition.[Figure not available: see fulltext.

  1. Unravelling the Natural and Anthropogenic Drivers of North Atlantic Tropical Cyclone Track Position since the Little Ice Age (United States)

    Baldini, L. M.; Baldini, J. U. L.; McElwaine, J.; Frappier, A. B.; Asmerom, Y.; Liu, K. B.; Prufer, K. M.; Ridley, H.; Polyak, V. J.; Kennett, D. J.; Macpherson, C.; Aquino, V. V.; Awe, J.; Breitenbach, S. F. M.


    In the last decade, stalagmites have been recognised as valuable archives of past hurricane activity. The characteristically low δ18O rainfall of tropical cyclones (TCs, including both hurricanes and tropical storms) is particularly well-preserved in fast-growing tropical speleothems. Here we present a new multi-proxy approach used to extract the western Caribbean TC signal from background wet season rainfall that, at our site in southern Belize, is driven by seasonal migration of the Intertropical Convergence Zone (ITCZ). The result is an annual 450-year record of western Caribbean TC activity that, when compared to documentary and statistical model-based reconstructions of North Atlantic TC activity, reveals a northward migration of dominant TC track since the height of Little Ice Age cooling. Importantly, the record reveals a reversal in the TC track position-North Atlantic sea surface temperature relationship between the pre-Industrial and Industrial Eras. During the pre-Industrial interval, TC track position migrated with the ITCZ toward the warmer hemisphere. Conversely, anthropogenic greenhouse gas and aerosol emissions during the Industrial Era have decoupled TC track position from the ITCZ through expansion of the Hadley Cell. This research suggests that under future greenhouse gas and aerosol emissions scenarios, the dominant TC track is likely to remain to the north. Combined with greenhouse gas-induced rising sea surface temperatures, the risk to the NE US population and financial centres is likely to increase in the future.

  2. Phylogeographic analysis elucidates the influence of the ice ages on the disjunct distribution of relict dragonflies in Asia.

    Directory of Open Access Journals (Sweden)

    Sebastian Büsse

    Full Text Available Unusual biogeographic patterns of closely related groups reflect events in the past, and molecular analyses can help to elucidate these events. While ample research on the origin of disjunct distributions of different organism groups in the Western Paleartic has been conducted, such studies are rare for Eastern Palearctic organisms. In this paper we present a phylogeographic analysis of the disjunct distribution pattern of the extant species of the strongly cool-adapted Epiophlebia dragonflies from Asia. We investigated sequences of the usually more conserved 18 S rDNA and 28 S rDNA genes and the more variable sequences of ITS1, ITS2 and CO2 of all three currently recognised Epiophlebia species and of a sample of other odonatan species. In all genes investigated the degrees of similarity between species of Epiophlebia are very high and resemble those otherwise found between different populations of the same species in Odonata. This indicates that substantial gene transfer between these populations occurred in the comparatively recent past. Our analyses imply a wide distribution of the ancestor of extant Epiophlebia in Southeast Asia during the last ice age, when suitable habitats were more common. During the following warming phase, its range contracted, resulting in the current disjunct distribution. Given the strong sensitivity of these species to climatic parameters, the current trend to increasing global temperatures will further reduce acceptable habitats and seriously threaten the existences of these last representatives of an ancient group of Odonata.

  3. Oceanographic mechanisms and penguin population increases during the Little Ice Age in the southern Ross Sea, Antarctica (United States)

    Yang, Lianjiao; Sun, Liguang; Emslie, Steven D.; Xie, Zhouqing; Huang, Tao; Gao, Yuesong; Yang, Wenqing; Chu, Zhuding; Wang, Yuhong


    The Adélie penguin is a well-known indicator for climate and environmental changes. Exploring how large-scale climate variability affects penguin ecology in the past is essential for understanding the responses of Southern Ocean ecosystems to future global change. Using ornithogenic sediments at Cape Bird, Ross Island, Antarctica, we inferred relative population changes of Adélie penguins in the southern Ross Sea over the past 500 yr, and observed an increase in penguin populations during the Little Ice Age (LIA; 1500-1850 AD). We used cadmium content in ancient penguin guano as a proxy of ocean upwelling and identified a close linkage between penguin dynamics and atmospheric circulation and oceanic conditions. During the cold period of ∼1600-1825 AD, a deepened Amundsen Sea Low (ASL) led to stronger winds, intensified ocean upwelling, enlarged Ross Sea and McMurdo Sound polynyas, and thus higher food abundance and penguin populations. We propose a mechanism linking Antarctic marine ecology and atmospheric/oceanic dynamics which can help explain and predict responses of Antarctic high latitudes ecosystems to climate change.

  4. Indian Ocean Dipole variability from Indonesian corals during the Little Ice Age (United States)

    Ellis, Bethany; Abram, Nerilie


    The Indian Ocean Dipole (IOD) is an ocean-atmosphere climate oscillation within the Indian Ocean basin, and one of Australasia's key climate drivers that influences the distribution of rainfall across the region. Future projections of the activity of the IOD suggest that positive IOD events may become more frequent with greenhouse warming. However, the short duration of instrumental records and biases in model representations of the IOD make it difficult to confidently separate anthropogenic-related trends from natural variability. To better understand natural IOD variability, high-resolution reconstructions of the Indian Ocean sea surface temperature (SST) are needed to provide a comprehensive view of IOD upwelling activity prior to the 20th Century. In this research, a fossil Porites coral has been used reconstruct past SST from the Sunda Strait, between the Indonesian islands of Java and Sumatra. Tectonic and volcanic activity in this region has preserved fossil coral material of various ages along the Sunda Strait coast. The southern Sunda Strait (6.5°S, 105.5°E) area is a key area for measuring IOD activity, as the cold upwelling waters in the eastern Indian Ocean, associated with a positive IOD event have a clear signature here that is captured by geochemical changes in coral skeletal material. The focus of this project is on a new 170 year, monthly resolution ∂18O record from a Krakatoa coral tsunami block dated to 1883 BP. This coral-based SST reconstruction reveals insights into the frequency and intensity of positive IOD events prior to anthropogenic climate change that gives context to the intensification of positive IOD events since the 1960s.

  5. Sediment yields of Wisconsin streams (United States)

    Hindall, S.M.; Flint, R.F.


    Sediment in Wisconsin streams causes economic and engineering problems in water management and reduces the value of water for nearly all uses. Sediment produces problems such as reduced reservoir capacity, navigation hazards, increased cost of water treatment, property damage, temporary loss of farmland, destruction of feeding and nesting grounds of fish, and destruction of wildlife habitat. Sediment in water also reduces the aesthetic value of surface waters and is detrimental to the State's tourist and recreation industry.

  6. Winter precipitation changes during the Medieval Climate Anomaly and the Little Ice Age in arid Central Asia (United States)

    Fohlmeister, Jens; Plessen, Birgit; Dudashvili, Alexey Sergeevich; Tjallingii, Rik; Wolff, Christian; Gafurov, Abror; Cheng, Hai


    The strength of the North Atlantic Oscillation (NAO) is considered to be the main driver of climate changes over the European and western Asian continents throughout the last millennium. For example, the predominantly warm Medieval Climate Anomaly (MCA) and the following cold period of the Little Ice Age (LIA) over Europe have been associated with long-lasting phases with a positive and negative NAO index. Its climatic imprint is especially pronounced in European winter seasons. However, little is known about the influence of NAO with respect to its eastern extent over the Eurasian continent. Here we present speleothem records (δ13C, δ18O and Sr/Ca) from the southern rim of Fergana Basin (Central Asia) revealing annually resolved past climate variations during the last millennium. The age control of the stalagmite relies on radiocarbon dating as large amounts of detrital material inhibit accurate 230Th dating. Present-day calcification of the stalagmite is most effective during spring when the cave atmosphere and elevated water supply by snow melting and high amount of spring precipitation provide optimal conditions. Seasonal precipitation variations cause changes of the stable isotope and Sr/Ca compositions. The simultaneous changes in these geochemical proxies, however, give also evidence for fractionation processes in the cave. By disentangling both processes, we demonstrate that the amount of winter precipitation during the MCA was generally higher than during the LIA, which is in line with climatic changes linked to the NAO index but opposite to the higher mountain records of Central Asia. Several events of strongly reduced winter precipitation are observed during the LIA in Central Asia. These dry winter events can be related to phases of a strong negative NAO index and all results reveal that winter precipitation over the central Eurasian continent is tightly linked to atmospheric NAO modes by the westerly wind systems.

  7. Response of a comprehensive climate model to a broad range of external forcings: relevance for deep ocean ventilation and the development of late Cenozoic ice ages (United States)

    Galbraith, Eric; de Lavergne, Casimir


    Over the past few million years, the Earth descended from the relatively warm and stable climate of the Pliocene into the increasingly dramatic ice age cycles of the Pleistocene. The influences of orbital forcing and atmospheric CO2 on land-based ice sheets have long been considered as the key drivers of the ice ages, but less attention has been paid to their direct influences on the circulation of the deep ocean. Here we provide a broad view on the influences of CO2, orbital forcing and ice sheet size according to a comprehensive Earth system model, by integrating the model to equilibrium under 40 different combinations of the three external forcings. We find that the volume contribution of Antarctic (AABW) vs. North Atlantic (NADW) waters to the deep ocean varies widely among the simulations, and can be predicted from the difference between the surface densities at AABW and NADW deep water formation sites. Minima of both the AABW-NADW density difference and the AABW volume occur near interglacial CO2 (270-400 ppm). At low CO2, abundant formation and northward export of sea ice in the Southern Ocean contributes to very salty and dense Antarctic waters that dominate the global deep ocean. Furthermore, when the Earth is cold, low obliquity (i.e. a reduced tilt of Earth's rotational axis) enhances the Antarctic water volume by expanding sea ice further. At high CO2, AABW dominance is favoured due to relatively warm subpolar North Atlantic waters, with more dependence on precession. Meanwhile, a large Laurentide ice sheet steers atmospheric circulation as to strengthen the Atlantic Meridional Overturning Circulation, but cools the Southern Ocean remotely, enhancing Antarctic sea ice export and leading to very salty and expanded AABW. Together, these results suggest that a `sweet spot' of low CO2, low obliquity and relatively small ice sheets would have poised the AMOC for interruption, promoting Dansgaard-Oeschger-type abrupt change. The deep ocean temperature and

  8. Little Ice Age climatic erraticism as an analogue for future enhanced hydroclimatic variability across the American Southwest. (United States)

    Loisel, Julie; MacDonald, Glen M; Thomson, Marcus J


    The American Southwest has experienced a series of severe droughts interspersed with strong wet episodes over the past decades, prompting questions about future climate patterns and potential intensification of weather disruptions under warming conditions. Here we show that interannual hydroclimatic variability in this region has displayed a significant level of non-stationarity over the past millennium. Our tree ring-based analysis of past drought indicates that the Little Ice Age (LIA) experienced high interannual hydroclimatic variability, similar to projections for the 21st century. This is contrary to the Medieval Climate Anomaly (MCA), which had reduced variability and therefore may be misleading as an analog for 21st century warming, notwithstanding its warm (and arid) conditions. Given past non-stationarity, and particularly erratic LIA, a 'warm LIA' climate scenario for the coming century that combines high precipitation variability (similar to LIA conditions) with warm and dry conditions (similar to MCA conditions) represents a plausible situation that is supported by recent climate simulations. Our comparison of tree ring-based drought analysis and records from the tropical Pacific Ocean suggests that changing variability in El Niño Southern Oscillation (ENSO) explains much of the contrasting variances between the MCA and LIA conditions across the American Southwest. Greater ENSO variability for the 21st century could be induced by a decrease in meridional sea surface temperature gradient caused by increased greenhouse gas concentration, as shown by several recent climate modeling experiments. Overall, these results coupled with the paleo-record suggests that using the erratic LIA conditions as benchmarks for past hydroclimatic variability can be useful for developing future water-resource management and drought and flood hazard mitigation strategies in the Southwest.

  9. Little Ice Age climatic erraticism as an analogue for future enhanced hydroclimatic variability across the American Southwest.

    Directory of Open Access Journals (Sweden)

    Julie Loisel

    Full Text Available The American Southwest has experienced a series of severe droughts interspersed with strong wet episodes over the past decades, prompting questions about future climate patterns and potential intensification of weather disruptions under warming conditions. Here we show that interannual hydroclimatic variability in this region has displayed a significant level of non-stationarity over the past millennium. Our tree ring-based analysis of past drought indicates that the Little Ice Age (LIA experienced high interannual hydroclimatic variability, similar to projections for the 21st century. This is contrary to the Medieval Climate Anomaly (MCA, which had reduced variability and therefore may be misleading as an analog for 21st century warming, notwithstanding its warm (and arid conditions. Given past non-stationarity, and particularly erratic LIA, a 'warm LIA' climate scenario for the coming century that combines high precipitation variability (similar to LIA conditions with warm and dry conditions (similar to MCA conditions represents a plausible situation that is supported by recent climate simulations. Our comparison of tree ring-based drought analysis and records from the tropical Pacific Ocean suggests that changing variability in El Niño Southern Oscillation (ENSO explains much of the contrasting variances between the MCA and LIA conditions across the American Southwest. Greater ENSO variability for the 21st century could be induced by a decrease in meridional sea surface temperature gradient caused by increased greenhouse gas concentration, as shown by several recent climate modeling experiments. Overall, these results coupled with the paleo-record suggests that using the erratic LIA conditions as benchmarks for past hydroclimatic variability can be useful for developing future water-resource management and drought and flood hazard mitigation strategies in the Southwest.

  10. Deposition of a saline giant in the Mississippian Windsor Group, Nova Scotia, and the nascent Late Paleozoic Ice Age (United States)

    MacNeil, Laura A.; Pufahl, Peir K.; James, Noel P.


    Saline giants are vast marine evaporite deposits that currently have no modern analogues and remain one of the most enigmatic of chemical sedimentary rocks. The Mississippian Windsor Group (ca. 345 Ma), Maritimes Basin, Atlantic Canada is a saline giant that consists of two evaporite-rich sedimentary sequences that are subdivided into five subzones. Sequence 1 is composed almost entirely of thick halite belonging to Subzone A (Osagean). Sequence 2 is in unconformable contact and comprised of stacked carbonate-evaporite peritidal cycles of Subzones B through E (Meramecian). Subzone B, the focus of research herein, documents the transition from wholly evaporitic to open marine conditions and thus, preserves an exceptional window into the processes forming saline giants. Lithofacies stacking patterns in Subzone B reveal that higher-order fluctuations in relative sea level produced nine stacked parasequences interpreted to reflect high frequency glacioeustatic oscillations during the onset of the Late Paleozoic Ice Age. Each parasequence reflects progradation of intertidal and sabkha sediments over subtidal carbonate and evaporite deposits. Dissimilarities in cycle composition between sub-basins imply the development of contrasting brine chemistries from differing recharge rates with the open ocean. What the Windsor Group shows is that evaporite type is ostensibly linked to the amplitude and frequency of sea level rise and fall during deposition. True saline giants, like the basinwide evaporites of Sequence 1, apparently require low amplitude, long frequency changes in sea level to promote the development of stable brine pools that are only periodically recharged with seawater. By contrast, the high amplitude, short frequency glacioeustatic variability in sea level that controlled the accumulation of peritidal evaporites in Subzone B produce smaller, subeconomic deposits with more complex facies relationships.

  11. Water Use in Wisconsin, 2005 (United States)

    Buchwald, Cheryl A.


    The U.S. Geological Survey (USGS) Wisconsin Water Science Center is responsible for presenting data collected or estimated for water withdrawals and diversions every 5 years to the National Water-Use Information Program (NWUIP). This program serves many purposes such as quantifying how much, where, and for what purpose water is used; tracking and documenting water-use trends and changes; and providing these data to other agencies to support hydrologic projects. In 2005, data at both the county and subbasin levels were compiled into the USGS national water-use database system; these data are published in a statewide summary report and a national circular. This publication, Water Use in Wisconsin, 2005, presents the water-use estimates for 2005; this publication also describes how these water-use data were determined (including assumptions used), limitations of using these data, and trends in water-use data presented to the NWUIP. Estimates of water use in Wisconsin indicate that about 8,608 million gallons per day (Mgal/d) were withdrawn during 2005. Of this amount, about 7,622 Mgal/d (89 percent) were from surface-water sources and about 986 Mgal/d (11 percent) were from ground-water sources. Surface water used for cooling at thermoelectric-power plants constituted the largest portion of daily use at 6,898 Mgal/d. Water provided by public-supply water utilities is the second largest use of water and totaled 552 Mgal/d. Public supply served approximately 71 percent of the estimated 2005 Wisconsin population of 5.54 million people; two counties - Milwaukee and Dane - accounted for more than one-third of the public-supply withdrawal. Industrial and irrigation were the next major water uses at 471 and 402 Mgal/d, respectively. Non-irrigational agricultural (livestock and aquaculture) accounted for approximately 155 Mgal/d and is similar to the combined withdrawal for the remaining water-use categories of domestic, commercial, and mining (131 Mgal/d). Data on water use

  12. Developing a Climatology of Cirrus Lidar Ratios Using Univeristy of Wisconsin HSRL Observations

    Directory of Open Access Journals (Sweden)

    Kuehn Ralph


    Full Text Available Measurements of ice cloud lidar ratio from the University of Wisconsin High Spectral Resolution Lidar System (UW HSRL are shown, for the period 2013/06/18-2013/11/04 in Hunstville, AL. These data were acquired as part of the SEAC4RS campaign. The layer-averaged median lidar ratio ,at 532 nm, for non-precipitating ice-clouds, 0.3 < OD < 3.0, observed during the experiment was determined to be 25.7 +/- 10.6 sr. As part of this work we’ve also developed an automated cloud and precipitation classification and detection algorithm.

  13. Improving mobility for Wisconsin's elderly : brief. (United States)


    By 2035, the number of elderly residents in Wisconsin is expected to nearly double, and one in four drivers on Wisconsin roads will be elderly. According to national statistics, the elderly are more likely to be involved in crashes on a per-mile basi...

  14. Updating progress in cancer control in Wisconsin. (United States)

    Treml, Kimberly B; McElroy, Jane A; Kaufman, Stephanie K; Remington, Patrick L; Wegner, Mark V


    In 1989, experts in cancer prevention, early detection, and treatment met in Madison to set the public health agenda for cancer control. Part of the plan defined target percent change in cancer mortality rates to be met by the year 2000. During the 1990s, public health and health care professionals developed programs and policies to reach these goals. The purpose of this analysis is to evaluate Wisconsin's progress in reducing cancer mortality and success in meeting the year 2000 objectives. Wisconsin mortality data for 1984-1986 and 1999-2001 were obtained from the Centers for Disease Control and Prevention, CDC Wonder. Percent change was calculated between the 2 time periods and compared to the 2000 target percent change for all-site cancer and site specific cancer mortality. All-site cancer mortality decreased by 7% from 1984-1986 to 1999-2001 with a greater than 16% decline in age groups <65 years. Mortality from breast, colorectal, and cervical cancer each decreased by at least 25%. Lung cancer and malignant melanoma mortality rates increased by 5% and 17%, respectively. Among additionally analyzed cancers, mortality decreased in prostate, stomach, and childhood cancers and increased in liver cancer and non-Hodgkin's lymphoma. The results of the state's cancer control effort are mixed. The year 2000 objectives were met for breast and colorectal cancer. Progress was made in reducing mortality from cervical cancer and from all sites combined, but the other year 2000 objectives were not met. Mortality rates increased for lung cancer and malignant melanoma during the 15-year period.

  15. Climate variability reflected by tree-ring width and δ18O in a heavily glaciated area of the Patagonian Andes since the Little Ice Age (United States)

    Meier, W. J. H.; Wernicke, J., Jr.; Braun, M.; Aravena, J. C.; Jaña, R.; Griessinger, J.


    Since the end of the Little Ice Age, the area of the Northern and Southern Patagonian ice sheet decreased by more than 14% and 11%, respectively. The melting increased since the last decade by 2.3%. The glaciers of Cordillera Darwin recorded a surface decrease of approximately 14% for the last 140 years. The reason for the excessive glacial change is often explained through the rise in temperature combined with a decrease in precipitation or a change in seasonality. Since a spatially coherent coverage of climatological measurement is lacking it is not possible to verify this assumption in a differentiated manner. Hence, the German- Chilean joint project "Responses of GlAciers, Biosphere and hYdrology to climate Variability and climate chAnge across the Southern Andes (GABY-VASA)" aims to determine the influence of long and short term climate variabilities (El Niño-Southern Oscillation (ENSO), Southern Hemisphere Annular Mode (SAM)) on the cryo- and biosphere. Trees growing at the glacier margins and at the natural treeline were sampled at four different locations ranging from the humid western part of the southern Andes (annual precipitation > 10.000mma-1) to the distinct dryer eastern part (annual precipitation meteorological back trajectories and the derivation of air masses since the Little Ice Age. It thus interlinks past and present climate and allows to draw conclusions about the driving forces of glacial change.

  16. Current glaciation of the Chikhachev ridge (South-Eastern Altai and its dynamics after maximum of the Little Ice Age

    Directory of Open Access Journals (Sweden)

    D. A. Ganyushkin


    Full Text Available Glaciation of the Chikhachev ridge (South-Eastern Altai remains poorly known: field observations were not performed since the mid-twentieth century, available schemes and estimates of the glaciation and its scale made on the basis of remote sensing cover only a part of the glaciers, reconstructions of the Little Ice Age (LIA glaciations are absent. This research was based on interpretation of the satellite images: Landsat-4 (1989, Landsat-7 (2001, and Spot-5 (2011, as well as with the use of data of the field season of 2015. Characteristics of glaciations of the Chikhachev ridge as the whole and of its individual centers (Talduair massif, Mongun-Taiga-Minor massif, and southern part of the Chikhachev ridge were determined for the first time. Recent glaciation is represented by 7 glaciers with their total area of 1.12 km2 in the Talduair massif, by 5 glaciers with total area of 0.75 km2 in the Mongun-Taiga-Minor massif, and by 85 glaciers with total area of 29 km2 in the southern part of the Chikhachev ridge. Since the LIA maximum, areas of glaciers decreased by 61% in the Talduair massif, by 74% in the Mongun-Taiga-Minor massif, by 56% in the southern part of the Chikhachev ridge with simultaneous lifting of the firn line by 50 m, 65 m, and 70 m, respectively.The largest rates of the glacier contractions were determined for the period 1989–2011. Different mechanisms of the glacier retreats were shown by the example of the glacier complexes Burgastyn-Gol (one-sided retreat and disintegration and the Grigorjev glacier (gradual retreat of the tongue. Retreat of the Grigorjev glacier has been reconstructed for the period from the LIA maximum until 2015. Average rate of the retreat increased from 1,6 m/year in 1957–1989 up to 11,3 m/year in 2011–2015. The present-day scales of the glaciers and rates of their retreating do not significantly differ from estimations made by other researchers for the nearest centers of glaciation of the

  17. Coeval Southward Migration of the ITCZ Over East Africa and South America During the Little Ice Age (United States)

    Brown, E. T.; Johnson, T. C.


    We have extracted high resolution records of past climate conditions from varved sediments accumulating near 10§ S in the north basin of Lake Malawi, the southernmost of the East African Rift lakes. Here we compare profiles of biogenic silica and Nb/Ti ratios spanning nearly 1000 years in Malawi with the Cariaco Basin high-resolution record of Haug et al. (2001), which is based primarily on sedimentary profiles of Fe and Ti. During the past 1000 years Nb/Ti and biogenic silica track one another in Malawi sediments, as observed for the late Glacial (Johnson et al., 2002). These signals have been interpreted this as a reflection of the intensity or frequency of north winds over the basin. Such winds carry Nb-rich volcaniclastic sediments into the lake and promote upwelling, favorable to diatom productivity. Johnson et al. (2002) attributed the greater frequency of north winds over the Malawi basin during "cold" episodes such as the Younger Dryas to southward shifts in the Intertropical Convergence Zone (ITCZ). Haug et al. (2001) have suggested that southward migration of the ITCZ over South America as such times has caused decreased rainfall and delivery of terrigenous clastics rich in Fe and Ti to the Cariaco basin. Over the past 1000 years, the trends in the African and South American records are remarkably similar. Both show evidence for the ITCZ being positioned more to the north during the Medieval Warm Period, more to the south during the Little Ice Age, and subsequently returning to the north. Both records also exhibit greater variability during the LIA, with three distinct southerly ITCZ excursions. Uncertainties inherent in the absolute chronologies preclude determination of whether or not these higher frequency variations are in phase at the two sites. The cause of the apparent coeval shifts of the ITCZ on both the African and South American continents during the past thousand years is yet to be explained. While North Atlantic temperature gradients may

  18. Cooling and societal change during the Late Antique Little Ice Age from 536 to around 660 AD

    Czech Academy of Sciences Publication Activity Database

    Büntgen, Ulf; Myglan, V. S.; Ljungqvist, F. C.; McCormick, M.; Di Cosmo, N.; Sigl, M.; Jungclaus, J.; Wagner, S.; Krusic, P. J.; Esper, J.; Kaplan, J. O.; de Vaan, M. A. C.; Luterbacher, J.; Wacker, L.; Tegel, W.; Kirdyanov, A. V.


    Roč. 9, č. 3 (2016), s. 231-236 ISSN 1752-0894 R&D Projects: GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : climate science * history * paleoclimate * Antique little ice Subject RIV: EH - Ecology, Behaviour Impact factor: 13.941, year: 2016

  19. Pain Intensity after an Ice Pack Application Prior to Venipuncture among School-Age Children: An Experimental Study (United States)

    Alalo, Fadeelah Mansour Ahmed; Ahmad, Awatef El Sayed; El Sayed, Hoda Mohamed Nafee


    Venipuncture and other invasive procedures as blood draws, intramuscular injections or heel pricks are the most commonly performed painful procedures in children. These can be a terrifying and painful experience for children and their families. The present study aimed to identify Pain intensity after an ice pack application prior to venipuncture…

  20. High-resolution sedimentary effects of post-Little Ice Age glacial recession in Hornsund (Svalbard) - insights from chirp and core data (United States)

    Dominiczak, Aleksander; Szczuciński, Witold; Moskalik, Mateusz; Forwick, Matthias


    As a result of global warming from the end of the Little Ice Age a fast withdrawal and loss of mass of many glaciers have been observed. The retreat has been particularly rapid in case of tidewater glaciers of Spitsbergen, where in an effect a new bays were formed and serve as glaciomarine sediment accumulation areas. The new depocenters in emerging bays are characterized by high sediment accumulation rates. Analysis and quantitative assessment of the processes occurring in these bays can enhance a better understanding of the dynamics of glaciers recession and bio-geochemical processes occurring in the fjords. This is particularly important because the subpolar fjords may be important storage for organic carbon on a global scale (Smith at al. 2015). In order to obtain a detailed high-resolution record of sedimentation history in the post Little Ice Age bays, 30 gravity cores and 18 box cores were collected along with detail seism acoustic surveys (Chirp) during three cruises on board of R/V Helmar Hansen in 2007, 2014 and 2015. The sediment cores revealed two major types of sediments: subglacial till and overlying laminated glacimarine mud with abundant ice rafted debris. The sediment accumulation rate of the latter is estimated to be on average in order of 1 to 5 cm per year. The periods of increase ice rafting are likely related to surge events. The dense Chirp survey grid spatial changeability in the post-Little Ice Age sediment cover. The amount and lithology of sediments in different parts of the bays also helped to link glacier dynamics with sedimentary effect. Our results confirms that despite similarities in lithology there are significant differences in sediment accumulation rates, probably driven by changes in accommodation spaces and sediment delivery. The record is also affected by effects of glacier surges. However, analyses of historical data enhanced the interpretation of sedimentary record and provide hints to identify the specific processes and

  1. Ice flow Modelling of the Greenland Ice Sheet

    DEFF Research Database (Denmark)

    Nielsen, Lisbeth Tangaa

    Models of ice flow have a range of application in glaciology, including investigating the large-scale response of ice sheets to changes in climate, assimilating data to estimate unknown conditions beneath the ice sheet, and in interpreting proxy records obtained from ice cores, among others. In t...... a steady state with respect to the reference climate at the end of the simulation and that the mass balance of the ice sheet at this time was more sensitive to recent climate fluctuations than the temperature forcing in the early or mid-Holocene.......Models of ice flow have a range of application in glaciology, including investigating the large-scale response of ice sheets to changes in climate, assimilating data to estimate unknown conditions beneath the ice sheet, and in interpreting proxy records obtained from ice cores, among others....... In this PhD project, the use of ice flow models for the interpretation of the age-structure of the Greenland ice sheet, i.e. the depth within the ice, at which ice deposited at given times are found at present day. Two different observational data sets of this archive were investigated. Further, paleo...

  2. The effect of wind, ice and waves on the in-situ burning of emulsions and aged oils

    International Nuclear Information System (INIS)

    Bech, C.; Sveum, P.; Buist, I.


    A series of small- and meso-scale in-situ burning tests was conducted on Spitsbergen to define the limitations and burn effectiveness of in-situ burning of water-in-oil emulsions in terms of water content, degree of evaporation, and film thickness; and to study how the presence of ice, waves, and wind affect in-situ burning. The tests were conducted in basins cut into the ice on a fjord. The size of the basins ranged from 4 to 300 m 2 . The largest basin was fitted with a wavemaker. Evaporated water-free oil was found to be easily ignited and to burn with high efficiency. The burn efficiency was not affected by waves. Highly evaporated oil with 25% water was hard to ignite with gelled gasoline. In the presence of waves, it was not possible to ignite a 12.5% stable water-in-oil emulsion. The presence of waves reduced the burn efficiency for emulsion with a low water content. The main problem with in-situ burning of emulsions is flame spreading; emulsions require a large initial burn area for the burn to be self-sustaining. Small ice floes and slush did not influence burn efficiency in a negative way. In-situ burning could not be accomplished in wind speeds above 10 m/s. 2 refs., 5 figs., 5 tabs

  3. Adaptation and rise: Little Ice Age challenges and social responses on the Trans-Tisza Region (Hungary) (United States)

    Pinke, Zsolt; Romhányi, Beatrix F.; Gábris, Gyula; Gyulai, Ferenc; Mravcsik, Zoltán; Pósa, Patricia; Ferenczi, László


    The studied 4.128 km2 Central European lowland region includes the Hortobágy landscape, a UNESCO World Heritage site and one of the most extensive protected natural grasslands of Europe. In the evolution of this semi-natural landscape human-nature interactions were characterised by gradual but extremely serious settlement abandonment during the 13th-17th centuries. The identification of the agents shaping this process has been widely discussed in the Hungarian landscape historiography. The statistical analysis of medieval archaeological sites indicating settlements showed that elevation means in the early period of the Little Ice Age (LIA) (mid-13th - mid-16th centuries) were significantly higher than in the Medieval Warm Epoch (MWE) (mid-10th - mid-13th centuries) (p≤0.01; n=549; α=0.05). This result supported our hypothesis that waterside settlements of the plain displaced vertically from the MWE to the LIA. Secondly, a GIS based zonal analysis suggested a strong spatial connection between the geomorphological zones (riparian, deep floodplain and sand plateau), the agro-ecological suitability zones (good-excellent, medium and low) and the population zones (with stable settlement pattern, deserted and uninhabited). E.g. the elevation means of archaeological sites in deserted zones proved significantly lower than those with stable settlement pattern (p≤0.01; n=381; α=0.05). Similarly, a statistical investigation of grain remains (narchaeologicalsite=79; ntaxon=751; nfindings=4.8 millions) of the Great Hungarian Plain (GHP) indicated that the early phase of the LIA saw the spreading of moorland plants and rye, the cereal most resistant to humidity and cool. When the relation of settlement patterns to soil conditions was analysed by ANOVA linear model, a significant spatial correlation appeared between the extension of the high and medium agro-ecological suitability zones and the number of settlements in each population zone of the five microregions (R2

  4. Effect of Probiotic Containing Ice-cream on Salivary Mutans Streptococci (SMS) Levels in Children of 6-12 Years of Age: A Randomized Controlled Double Blind Study with Six-months Follow Up. (United States)

    Ashwin, Devasya; Ke, Vijayaprasad; Taranath, Mahanthesh; Ramagoni, Naveen Kumar; Nara, Asha; Sarpangala, Mythri


    To evaluate the caries risk based on the salivary levels of streptococcus mutans in children of 6-12 years of age group before and after consuming probiotic ice-cream containing Bifidobacterium lactis Bb-12 and Lactobacillus acidophilus La-5. A double blind, placebo controlled trial was carried out in 60 children aged between 6 to 12 years with zero decayed, missing, and filled teeth (DMFT). They were randomly divided into two equal groups. Saliva sample were collected before the consumption of ice-cream and Streptococcus mutans count was calculated and recorded as baseline data. For the next seven days both the groups were given ice creams marked as A and B. Saliva samples were collected after ice-cream consumption at the end of study period and also after a washout period of 30 days and again after six months. Samples were inoculated and colonies were counted. On statistical evaluation by students paired t-test, probiotic ice-cream brought significant reduction in the Streptococcus mutans count after seven days of ice-cream ingestion (pice-cream consumption. After six months of the study period in both the groups the salivary levels of Streptococcus mutans was similar to the baseline. Probiotic ice-cream containing Bifidobacterium lactis Bb-12 and Lactobacillus acidophilus La-5 can cause reduction in caries causative organism. The dosage of the probiotic organisms for the long term or synergetic effect on the oral health are still needed to be explored.

  5. Predicting Scour of Bedrock in Wisconsin (United States)


    This research evaluates the scour potential of rocks supporting Wisconsin DOT bridge foundations. Ten highway bridges were selected for this study, of which seven are supported by shallow foundations, and five were built on sandstone in rivers/stream...

  6. Fuelwood production and sources in Wisconsin, 1981. (United States)

    James E. Blyth; E. Michael Bailey; W. Brad Smith


    Discusses and analyzes the 1981 Wisconsin fuelwood production from roundwood and primary wood-using mill residue. Analyzes production by geographic area, type of producer, species, landowner class, type of land, and tree source.

  7. Ice Cores (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, atmospheric trace gases, and other aspects of climate and environment derived from ice cores drilled on glaciers and ice...

  8. Ancient ice (United States)


    Simon Belt, Guillaume Massé and colleagues rammed their way through sheets of ice, spotting some polar bears on the way, in their attempt to reconstruct Arctic sea-ice records covering thousands of years.

  9. Improving Outreach and Surveillance Efforts Following a Large-Scale Carbon Monoxide Poisoning in Wisconsin. (United States)

    Creswell, Paul D; Vogt, Christy M; Wozniak, Ryan J; Camponeschi, Jenny; Werner, Mark A; Meiman, Jonathan G

    In December 2014, the largest carbon monoxide (CO) poisoning in Wisconsin's history occurred at an ice arena. Following this event, the Wisconsin Environmental Public Health Tracking (WI EPHT) Program sought to improve outreach and surveillance efforts. WI EPHT designed and distributed educational materials on CO poisoning prevention and surveyed stakeholders to gauge the effectiveness of outreach efforts. To enhance surveillance, WI EPHT utilized data from the Wisconsin Poison Center (WPC) to generate real-time alerts of anomalous numbers of CO-related calls. WI EPHT found that 42% of stakeholders reviewed the outreach materials, and 1 ice arena had installed a CO detector as a result. CO alerts were developed using WPC data and are now routinely used in statewide public health surveillance. WI EPHT staff improved CO poisoning prevention outreach and saw a positive response among stakeholders. This work demonstrates ways that health agencies can improve outreach and surveillance for CO poisoning. Improvements in these areas can bolster public health response and may prevent CO-related illness and injury.

  10. Ice Cream

    NARCIS (Netherlands)

    Scholten, E.


    Ice cream is a popular dessert, which owes its sensorial properties (mouth feel) to its complex microstructure. The microstructure is a result of the combination of the ingredients and the production process. Ice cream is produced by simultaneous freezing and shearing of the ice cream mix, which


    Directory of Open Access Journals (Sweden)

    V. G. Chuvardinsky


    Full Text Available The hypothesis of Permo-Carboniferous glaciation appeared for the first time in the middle of XIX century based on findings of tillite outcrop and striated boulder in India and Australia. After that such boulder deposits were found in South and Equatorial Africa, Europe, Kazakhstan, South and North America, on the Arabian Peninsula. The latest place where tillites were found is Antarctica. Over 150-200 years the hypothesis turned into an unshakeable theory and, together with the theory of powerful Quaternary glaciation, was wildly introduced into Earth science (geoscience, it was definitely considered as a fundamental and epoch-making scientific achievement. During this period the scientific groups from different countries – botanists, zoologists, paleogeographers, climatologists and geologists collected rich, sometimes unique, factual material concerning plant and animal life of the late Paleozoic and wide formations of coal deposits. The paleogeography reconstructions of almost global glaciation with ice thickness of 6 km (! were also informative; this glaciation was called “The Great Permo-Carboniferous ice age”. It was impossible to think about debunking this theory. Therefore, it is worth mentioning that many scientists, both foreign and Russian ones, can be regarded as our extramural co-authors. The fact that we, unlike them, try to disprove the glacial theory, does not change the matter – it was impossible to prove the absence of this glaciation without the powerful glacial doctrine created by the scientific community and without huge factual material collected by them. The geological features of the Permo-Carboniferous glaciation are based on the same criteria as for the Quaternary glaciation. First of all, this is “an ice exaltation relief” – they are roche moutonnée (sheepbacks, polished rocks, striation, furrows on bedrock and boulders, tillites. It allows using the well-known principle of actuality. The author

  12. On the nature of the dirty ice at the bottom of the GISP2 ice core (United States)

    Bender, Michael L.; Burgess, Edward; Alley, Richard B.; Barnett, Bruce; Clow, Gary D.


    We present data on the triple Ar isotope composition in trapped gas from clean, stratigraphically disturbed ice between 2800 and 3040 m depth in the GISP2 ice core, and from basal dirty ice from 3040 to 3053 m depth. We also present data for the abundance and isotopic composition of O 2 and N 2, and abundance of Ar, in the basal dirty ice. The Ar/N 2 ratio of dirty basal ice, the heavy isotope enrichment (reflecting gravitational fractionation), and the total gas content all indicate that the gases in basal dirty ice originate from the assimilation of clean ice of the overlying glacier, which comprises most of the ice in the dirty bottom layer. O 2 is partly to completely depleted in basal ice, reflecting active metabolism. The gravitationally corrected ratio of 40Ar/ 38Ar, which decreases with age in the global atmosphere, is compatible with an age of 100-250 ka for clean disturbed ice. In basal ice, 40Ar is present in excess due to injection of radiogenic 40Ar produced in the underlying continental crust. The weak depth gradient of 40Ar in the dirty basal ice, and the distribution of dirt, indicate mixing within the basal ice, while various published lines of evidence indicate mixing within the overlying clean, disturbed ice. Excess CH 4, which reaches thousands of ppm in basal dirty ice at GRIP, is virtually absent in overlying clean disturbed ice, demonstrating that mixing of dirty basal ice into the overlying clean ice, if it occurs at all, is very slow. Order-of-magnitude estimates indicate that the mixing rate of clean ice into dirty ice is sufficient to maintain a steady thickness of dirty ice against thinning from the mean ice flow. The dirty ice appears to consist of two or more basal components in addition to clean glacial ice. A small amount of soil or permafrost, plus preglacial snow, lake or ground ice could explain the observations.

  13. On the nature of the dirty ice at the bottom of the GISP2 ice core (United States)

    Bender, Michael L.; Burgess, Edward; Alley, Richard B.; Barnett, Bruce; Clow, Gary D.


    We present data on the triple Ar isotope composition in trapped gas from clean, stratigraphically disturbed ice between 2800 and 3040m depth in the GISP2 ice core, and from basal dirty ice from 3040 to 3053m depth. We also present data for the abundance and isotopic composition of O2 and N2, and abundance of Ar, in the basal dirty ice. The Ar/N2 ratio of dirty basal ice, the heavy isotope enrichment (reflecting gravitational fractionation), and the total gas content all indicate that the gases in basal dirty ice originate from the assimilation of clean ice of the overlying glacier, which comprises most of the ice in the dirty bottom layer. O2 is partly to completely depleted in basal ice, reflecting active metabolism. The gravitationally corrected ratio of 40Ar/38Ar, which decreases with age in the global atmosphere, is compatible with an age of 100-250ka for clean disturbed ice. In basal ice, 40Ar is present in excess due to injection of radiogenic 40Ar produced in the underlying continental crust. The weak depth gradient of 40Ar in the dirty basal ice, and the distribution of dirt, indicate mixing within the basal ice, while various published lines of evidence indicate mixing within the overlying clean, disturbed ice. Excess CH4, which reaches thousands of ppm in basal dirty ice at GRIP, is virtually absent in overlying clean disturbed ice, demonstrating that mixing of dirty basal ice into the overlying clean ice, if it occurs at all, is very slow. Order-of-magnitude estimates indicate that the mixing rate of clean ice into dirty ice is sufficient to maintain a steady thickness of dirty ice against thinning from the mean ice flow. The dirty ice appears to consist of two or more basal components in addition to clean glacial ice. A small amount of soil or permafrost, plus preglacial snow, lake or ground ice could explain the observations.

  14. Legal Ice?

    DEFF Research Database (Denmark)

    Strandsbjerg, Jeppe

    The idealised land|water dichotomy is most obviously challenged by ice when ‘land practice’ takes place on ice or when ‘maritime practice’ is obstructed by ice. Both instances represent disparity between the legal codification of space and its social practice. Logically, then, both instances call...... for alternative legal thought and practice; in the following I will emphasise the former and reflect upon the relationship between ice, law and politics. Prior to this workshop I had worked more on the relationship between cartography, geography and boundaries than specifically on ice. Listening to all...

  15. 75 FR 56597 - University of Wisconsin; University of Wisconsin Nuclear Reactor Environmental Assessment and... (United States)


    ... when solid waste is generated from use of the UWNR, it is transferred to the University of Wisconsin.... In the years that solid waste was generated, less than 400 milliCuries of solid waste was transferred...; University of Wisconsin Nuclear Reactor Environmental Assessment and Finding of No Significant Impact The U.S...

  16. High-resolution chronology for deglaciation of the Patagonian Ice Sheet at Lago Buenos Aires (46.5°S) revealed through varve chronology and Bayesian age modelling (United States)

    Bendle, Jacob M.; Palmer, Adrian P.; Thorndycraft, Varyl R.; Matthews, Ian P.


    Glaciolacustrine varves offer the potential to construct continuous, annually-resolved chronologies for ice-sheet deglaciation, and improved understanding of glacier retreat dynamics. This paper investigates laminated glaciolacustrine sediments deposited around the waning margins of the Patagonian Ice Sheet, following the local Last Glacial Maximum (LGM). Detailed macro- and microfacies analyses confirm an annual (varve) structure within these sediments. The correlation of annual layers (varves) across five sites in eastern Lago Buenos Aires yields a 994 ± 36 varve-year (vyr) chronology and thickness record. The floating chronology has been anchored to the calendar-year timescale through identification of the Ho tephra (17,378 ± 118 cal a BP) in the varve sequences. Using a Bayesian age model to integrate the new varve chronology with published moraine ages, the onset of deglaciation at 46.5°S is dated to 18,086 ± 214 cal a BP. New age estimates for deglacial events are combined with high-resolution analysis of varve thickness trends, and new lithostratigraphic data on ice-margin position(s), to reconstruct ice-margin retreat rates for the earliest ca. 1000 years of ice-sheet demise. Glacier retreat rates were moderate (5.3-10.3 m yr-1) until 17,322 ± 115 cal a BP, but subsequently accelerated (15.4-18.0 m yr-1). Sustained influxes of ice-rafted debris (IRD) after 17,145 ± 122 cal a BP suggest retreat rates were enhanced by calving after ice contracted into deeper lake waters. Ice persisted in eastern Lago Buenos Aires until at least 16,934 ± 116 cal a BP, after which the glacier started to retreat towards the Patagonian mountains.

  17. Rehabilitation of Delavan Lake, Wisconsin (United States)

    Robertson, Dale M.; Goddard, Gerald L.; Helsel, D.R.; MacKinnon, Kevin L.


    A comprehensive rehabilitation plan was developed and implemented to shift Delavan Lake, Wisconsin, from a hypereutrophic to a mesotrophic condition. The plan was threefold: (1) reduce external phosphorus (P) loading by applying Best Management Practices in the watershed, enhance an existing wetland, and short-circuit the inflows through the lake, (2) reduce internal P loading by treating the sediments with alum and removing carp, and (3) rehabilitate the fishery by removing carp and bigmouth buffalo and adding piscivores (biomanipulation). The first and second parts of the plan met with only limited success. With only minor reductions in internal and external P loading, P concentrations in the lake returned to near pre-treatment concentrations. The intensive biomanipulation and resulting trophic cascade (increased piscivores, decreased planktivores, increased large zooplankton populations, and reduced phytoplankton populations) eliminated most of the original problems in the lake (blue-green algal blooms and limited water clarity). However, now there is extensive macrophyte growth and abundant filamentous algae. Without significantly reducing the sources of the problems (high P loading) in Delavan Lake, the increased water clarity may not last. With an improved understanding of the individual components of this rehabilitation program, better future management plans can be developed for Delavan Lake and other lakes and reservoirs with similar eutrophication problems.

  18. Little Ice Age mapping as a tool for identifying hazard in the paraglacial environment: The case study of Trentino (Eastern Italian Alps) (United States)

    Zanoner, Thomas; Carton, Alberto; Seppi, Roberto; Carturan, Luca; Baroni, Carlo; Salvatore, Maria Cristina; Zumiani, Matteo


    The Little Ice Age (LIA) is a well-recognized climatic event during which the glaciers in the Alps advanced and reached their maximum Holocene extent. During their retreat following the LIA, the glaciers left large areas of loose or poorly consolidated glacial deposits in their forelands, which are subject to paraglacial reworking and may represent potential hazards for human infrastructures. In this study, we present a regional scale mapping of the LIA and post-LIA glacial deposits and a reconstruction of the maximum LIA extents of glaciers in the same area. This work is motivated by a local law requiring the classification of areas subject to natural hazards in Trentino (Italian Alps). Results highlight that glaciers shrunk by 63% from the LIA maximum, leaving 30 km2 of unconsolidated deposits, which are subject to geomorphic paraglacial processes. Potentially hazardous consequences can occur, in particular, during high-magnitude instantaneous events, causing debris and mud flows, mass wasting from debris-covered ice, and floods from small moraine-dammed lakes.

  19. Tickborne Powassan virus infections among Wisconsin residents. (United States)

    Johnson, Diep K Hoang; Staples, J Erin; Sotir, Mark J; Warshauer, David M; Davis, Jeffrey P


    Powassan virus (POWV) is a tickborne Flavivirus that causes a rare but potentially life-threatening illness. The first reported case of POWV infection in a Wisconsin resident occurred in 2003. Enhanced surveillance and testing detected 2 additional cases. Patient specimens with a positive or equivocal immunoglobulin M (IgM) antibody to an arbovirus were sent from commercial laboratories to the Wisconsin State Laboratory of Hygiene and forwarded to the Centers for Disease Control and Prevention (CDC) for confirmatory testing. Patients with laboratory confirmed POWV infections were interviewed to obtain demographic, clinical, and epidemiologic information. POWV infections were confirmed in 3 adult Wisconsin residents in 2003, 2006, and 2007; illness onsets occurred during May and June. Two patients were hospitalized and all survived. One patient had a dual infection with POWV and Anaplasma phaghocytophilum. Specimens from all 3 patients were initially reported as positive for IgM antibody to either St Louis encephalitis or California serogroup viruses; POWV-specific antibody was detected during confirmatory testing at the CDC. Each patient had exposures to known or likely tick habitats in different counties within 30 days before illness onset. These are the first diagnosed human POWV infections in Wisconsin. Because all 3 patients were initially identified as having other arboviral infections using commercial screening kits, routine confirmatory testing is essential for proper diagnosis of most arboviral infections. Wisconsin residents should be educated regarding risks of acquiring and ways to prevent POWV infection and other tickborne diseases when spending time outdoors.

  20. Implementing high-speed rail in Wisconsin peer exchange. (United States)


    The Wisconsin Department of Transportation Division of Transportation Investment Management hosted : a peer exchange on June 2 -4, 2009 in Milwaukee, Wisconsin. Representatives from four state DOTs and : two freight railroads joined representatives f...

  1. Islands in the ice

    DEFF Research Database (Denmark)

    Jørgensen, Tina; Kjær, Kurt H.; Haile, James Seymour


    Nunataks are isolated bedrocks protruding through ice sheets. They vary in age, but represent island environments in 'oceans' of ice through which organism dispersals and replacements can be studied over time. The J.A.D. Jensen's Nunataks at the southern Greenland ice sheet are the most isolated...... nunataks on the northern hemisphere - some 30 km from the nearest biological source. They constitute around 2 km(2) of ice-free land that was established in the early Holocene. We have investigated the changes in plant composition at these nunataks using both the results of surveys of the flora over...... the last 130 years and through reconstruction of the vegetation from the end of the Holocene Thermal Maximum (5528 ± 75 cal year BP) using meta-barcoding of plant DNA recovered from the nunatak sediments (sedaDNA). Our results show that several of the plant species detected with sedaDNA are described from...

  2. Sea Ice (United States)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.


    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  3. Climate variability during the Medieval Climate Anomaly and Little Ice Age based on ostracod faunas and shell geochemistry from Biscayne Bay, Florida: Chapter 14 (United States)

    Cronin, Thomas M.; Wingard, G. Lynn; Dwyer, Gary S.; Swart, Peter K.; Willard, Debra A.; Albietz, Jessica


    An 800-year-long environmental history of Biscayne Bay, Florida, is reconstructed from ostracod faunal and shell geochemical (oxygen, carbon isotopes, Mg/Ca ratios) studies of sediment cores from three mudbanks in the central and southern parts of the bay. Using calibrations derived from analyses of modern Biscayne and Florida Bay ostracods, palaeosalinity oscillations associated with changes in precipitation were identified. These oscillations reflect multidecadal- and centennial-scale climate variability associated with the Atlantic Multidecadal Oscillation during the late Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA). Evidence suggests wetter regional climate during the MCA and drier conditions during the LIA. In addition, twentieth century anthropogenic modifications to Everglades hydrology influenced bay circulation and/or processes controlling carbon isotopic composition.

  4. Ice Surfaces (United States)

    Shultz, Mary Jane


    Ice is a fundamental solid with important environmental, biological, geological, and extraterrestrial impact. The stable form of ice at atmospheric pressure is hexagonal ice, Ih. Despite its prevalence, Ih remains an enigmatic solid, in part due to challenges in preparing samples for fundamental studies. Surfaces of ice present even greater challenges. Recently developed methods for preparation of large single-crystal samples make it possible to reproducibly prepare any chosen face to address numerous fundamental questions. This review describes preparation methods along with results that firmly establish the connection between the macroscopic structure (observed in snowflakes, microcrystallites, or etch pits) and the molecular-level configuration (detected with X-ray or electron scattering techniques). Selected results of probing interactions at the ice surface, including growth from the melt, surface vibrations, and characterization of the quasi-liquid layer, are discussed.

  5. Geophysical features influence the climate change sensitivity of northern Wisconsin pine and oak forests. (United States)

    Tweiten, Michael A; Calcote, Randy R; Lynch, Elizabeth A; Hotchkiss, Sara C; Schuurman, Gregor W


    Landscape-scale vulnerability assessment from multiple sources, including paleoecological site histories, can inform climate change adaptation. We used an array of lake sediment pollen and charcoal records to determine how soils and landscape factors influenced the variability of forest composition change over the past 2000 years. The forests in this study are located in northwestern Wisconsin on a sandy glacial outwash plain. Soils and local climate vary across the study area. We used the Natural Resource Conservation Service's Soil Survey Geographic soil database and published fire histories to characterize differences in soils and fire history around each lake site. Individual site histories differed in two metrics of past vegetation dynamics: the extent to which white pine (Pinus strobus) increased during the Little Ice Age (LIA) climate period and the volatility in the rate of change between samples at 50-120 yr intervals. Greater increases of white pine during the LIA occurred on sites with less sandy soils (R² = 0.45, P climate (R² = 0.55, P change between samples was positively associated with LIA fire frequency (R² = 0.41, P change and rate-of-change volatility were associated with higher fire frequency. Over longer (multi-centennial) time frames, forest composition change, especially increased white pine, shifted most in sites with more soil moisture. Our results show that responsiveness of forest composition to climate change was influenced by soils, local climate, and fire. The anticipated climatic changes in the next century will not produce the same community dynamics on the same soil types as in the past, but understanding past dynamics and relationships can help us assess how novel factors and combinations of factors in the future may influence various site types. Our results support climate change adaptation efforts to monitor and conserve the landscape's full range of geophysical features.


    Directory of Open Access Journals (Sweden)

    Yurij K. Vasil’chuk


    Full Text Available The paper summarises stable-isotope research on massive ice in the Russian and North American Arctic, and includes the latest understanding of massive-ice formation. A new classification of massive-ice complexes is proposed, encompassing the range and variabilityof massive ice. It distinguishes two new categories of massive-ice complexes: homogeneousmassive-ice complexes have a similar structure, properties and genesis throughout, whereasheterogeneous massive-ice complexes vary spatially (in their structure and properties andgenetically within a locality and consist of two or more homogeneous massive-ice bodies.Analysis of pollen and spores in massive ice from Subarctic regions and from ice and snow cover of Arctic ice caps assists with interpretation of the origin of massive ice. Radiocarbon ages of massive ice and host sediments are considered together with isotope values of heavy oxygen and deuterium from massive ice plotted at a uniform scale in order to assist interpretation and correlation of the ice.

  7. The Legal Status of Homemakers in Wisconsin. (United States)

    Melli, Marygold Shire

    This report focuses on laws in the state of Wisconsin as they relate to homemakers. Four areas are discussed, each in separate sections: marriage, widowhood, divorce, and wife abuse. The section on marriage includes information on property rights, disability and death of homemaker, federal Equal Credit Opportunity Act, domicile, interspousal…

  8. Divided Wisconsin: Partisan Spatial Electoral Realignment (United States)

    Zaniewski, Kazimierz J.; Simmons, James R.


    When the Republican and Democratic presidential candidates head into the general election this fall, they will be courting votes from a statewide electorate that has dramatically shifted over time, mirroring the political polarization that is happening across the country. Over the last three decades, Wisconsin's political geography has evolved…

  9. Wisconsin Public Schools at a Glance, 2016 (United States)

    Wisconsin Department of Public Instruction, 2016


    "Wisconsin Public Schools at a Glance" provides in a single page document statistical information on the following topics: (1) Total number of public schools (2015-16); (2) Student (2015-16); (3) Attendance & Graduation (2014-15);(4) Staff (2013-14); (5) School Funding; and (6) Student Performance (2014-15). [For the previous report…

  10. Wisconsin Public Schools at a Glance (United States)

    Wisconsin Department of Public Instruction, 2014


    "Wisconsin Public Schools at a Glance" provides in a single page document statistical information on the following topics: (1) Total number of public schools (2014-15); (2) Staff (2013-14); (3) Students (2013-14);(4) Report Cards (2013-14); (5) Attendance and Graduation (2012-13); (6) Student Performance (2013-14); and (7) School Funding.

  11. The University of Wisconsin OAO operating system (United States)

    Heacox, H. C.; Mcnall, J. F.


    The Wisconsin OAO operating system is presented which consists of two parts: a computer program called HARUSPEX, which makes possible reasonably efficient and convenient operation of the package and ground operations equipment which provides real-time status monitoring, commanding and a quick-look at the data.

  12. Genetic Analysis of Termite Colonies in Wisconsin (United States)

    R.A. Arango; D.A. Marschalek; F. Green III; K.F. Raffa; M.E. Berres


    The objective of this study was to document current areas of subterranean termite activity in Wisconsin and to evaluate genetic characteristics of these northern, peripheral colonies. Here, amplified fragment-length polymorphism was used to characterize levels of inbreeding, expected heterozygosity, and percent polymorphism within colonies as well as genetic structure...

  13. Stakeholders' Perceptions of Parcelization in Wisconsin's Northwoods (United States)

    Mark G. Rickenbach; Paul H. Gobster


    Parcelization, the process by which relatively large forest ownerships become subdivided into smaller ones, is often related to changes in ownership and can bring changes to the use of the land. Landowners, resource professionals, and others interested in Wisconsin's Northwoods were asked their views on parcelization in a series of stakeholder forums. We analyzed...

  14. Sorghum as a forage in Wisconsin (United States)

    Growing moderate quality forages that meet, but do not exceed, requirements of dairy replacement heifers is not a common practice in Wisconsin; however, this forage management option would have a positive impact on the dairy industry. It is typical for heifers to gain excessive bodyweight when they ...

  15. Comment on: “Solar Minima, Earth's rotation and Little Ice Ages in the past and in the future. The North Atlantic-European case” (Mörner, 2010) (United States)

    Cheddadi, R.; Guiot, J.


    This is a comment on the following publication: Mörner, N-A. 2010. Solar Minima, Earth's rotation and Little Ice Ages in the past and in the future. The North Atlantic-European case. Global and Planetary Change, 72: 282-293.

  16. The late Little Ice Age landslide calamity in North Bohemia: Triggers, impacts and post-landslide development reconstructed from documentary data (case study of the Kozi vrch Hill landslide)

    Czech Academy of Sciences Publication Activity Database

    Raška, P.; Zábranský, V.; Brázdil, Rudolf; Lamková, J.


    Roč. 255, feb (2016), s. 95-107 ISSN 0169-555X Institutional support: RVO:67179843 Keywords : flysch carpathians * shallow landslides * rainfall intensity * duration control * climatic -change * central-europe * debris flows * czechia * state * Landslide reconstruction * Documentary data * Little Ice Age * North Bohemia Subject RIV: EH - Ecology, Behaviour Impact factor: 2.958, year: 2016

  17. Strong Gradients in Forest Sensitivity to Climate Change Revealed by Dynamics of Forest Fire Cycles in the Post Little Ice Age Era (United States)

    Drobyshev, Igor; Bergeron, Yves; Girardin, Martin P.; Gauthier, Sylvie; Ols, Clémentine; Ojal, John


    The length of the fire cycle is a critical factor affecting the vegetation cover in boreal and temperate regions. However, its responses to climate change remain poorly understood. We reanalyzed data from earlier studies of forest age structures at the landscape level, in order to map the evolution of regional fire cycles across Eastern North American boreal and temperate forests, following the termination of the Little Ice Age (LIA). We demonstrated a well-defined spatial pattern of post-LIA changes in the length of fire cycles toward lower fire activity during the 1800s and 1900s. The western section of Eastern North America (west of 77°W) experienced a decline in fire activity as early as the first half of the 1800s. By contrast, the eastern section showed these declines as late as the early 1900s. During a regionally fire-prone period of the 1910s-1920s, forests in the western section of Eastern boreal North America burned more than forests in the eastern section. The climate appeared to dominate over vegetation composition and human impacts in shaping the geographical pattern of the post-LIA change in fire activity. Changes in the atmospheric circulation patterns following the termination of the LIA, specifically changes in Arctic Oscillation and the strengthening of the Continental Polar Trough, were likely drivers of the regional fire dynamics.

  18. Legal Ice?

    DEFF Research Database (Denmark)

    Strandsbjerg, Jeppe

    for alternative legal thought and practice; in the following I will emphasise the former and reflect upon the relationship between ice, law and politics. Prior to this workshop I had worked more on the relationship between cartography, geography and boundaries than specifically on ice. Listening to all...... the interesting conversations during the workshop, however, made me think that much of the concern with the Polar Regions in general, and the presence of ice in particular, reverberates around the question of how to accommodate various geographical presences and practices within the regulatory framework that we...

  19. Childhood body mass index at 5.5 years mediates the effect of prenatal maternal stress on daughters' age at menarche: Project Ice Storm. (United States)

    Duchesne, A; Liu, A; Jones, S L; Laplante, D P; King, S


    Early pubertal timing is known to put women at greater risk for adverse physiological and psychological health outcomes. Of the factors that influence girls' pubertal timing, stress experienced during childhood has been found to advance age at menarche (AAM). However, it is not known if stress experienced by mothers during or in the months before conception can be similarly associated with earlier pubertal timing. Prenatal maternal stress (PNMS) is associated with metabolic changes, such as increased childhood adiposity and risk of obesity, that have been associated with earlier menarchal age. Using a prospective longitudinal design, the present study tested whether PNMS induced by a natural disaster is either directly associated with earlier AAM, or whether there is an indirect association mediated through increased girls' body mass index (BMI) during childhood. A total of 31 girls, whose mothers were exposed to the Quebec's January 1998 ice storm during pregnancy were followed from 6 months to 5 1/2 to 5.5 years of age. Mother's stress was measured within 6 months of the storm. BMI was measured at 5.5 years, and AAM was assessed through teen's self-report at 13.5 and 15.5 years of age. Results revealed that greater BMI at 5.5 years mediated the effect of PNMS on decreasing AAM [B=-0.059, 95% confidence intervals (-0.18, -0.0035)]. The present study is the first to demonstrate that maternal experience of stressful conditions during pregnancy reduces AAM in the offspring through its effects on childhood BMI. Future research should consider the impact of AAM on other measures of reproductive ability.

  20. Little Ice Age versus Present Day: Comparison of Temperature, Precipitation and Seasonality in Speleothem Records from the Han-sur-Lesse Cave, Belgium. (United States)

    Vansteenberge, S.; Van Opdenbosch, J.; Van Rampelbergh, M.; Verheyden, S.; Keppens, E.; Cheng, H.; Edwards, R. L.; Claeys, P. F.


    The Proserpine stalagmite is a 2 m large, tabular-shaped speleothem located in the Han-sur-Lesse cave in Belgium. The speleothem formed over the last 1000 years and is still growing. High-accuracy U/Th datings have indicated exceptionally high growth-rates of up to 2 mm per year. This, together with a well expressed annual layering, makes the Proserpine stalagmite an ideal candidate for high-resolution paleoclimate reconstructions of the last millennium. Previous work, including over 10 years of cave monitoring, has already learned us how short-term, i.e. decadal to seasonal, climate variations are incorporated within speleothem calcite from the Han-sur-Lesse cave system. It has been shown that δ18O and δ13C stable isotopes and trace element proxies of recently formed calcite reflect seasonal variations in temperature and precipitation of the near-cave environment (Verheyden et al, 2008; Van Rampelbergh et al., 2014). Now, this knowledge was used to infer local climate parameters further back in time to the period of +/- 1620-1630 CE, corresponding to one of the cold peaks within the Little Ice Age. Speleothem calcite was sampled at sub-annual resolution, with approximately 11 samples per year, for stable isotope analysis. LA-ICP-MS and µXRF analyses resulted in time series of trace elements. Preliminary results indicate a well expressed seasonal signal in δ13C and trace element composition but a multi-annual to decadal trend in δ18O. This combined proxy study eventually enables comparison of the expression of seasonality and longer term climate variations between a Little Ice Age cold peak and Present Day. References: Verheyden, S. et al., 2008, Monitoring climatological, hydrological and geochemical parameters in the Père Noël cave (Belgium): implication for the interpretation of speleothem isotopic and geochemical time-series. International Journal of Speleology, 37(3), 221-234. Van Rampelbergh, M. et al., 2014, Seasonal variations recorded in cave

  1. A warm and wet Little Climatic Optimum and a cold and dry Little Ice Age in the southern Rocky Mountains, USA

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, K.L.


    In the next century, increases in atmospheric trace gas concentration could warm the global average temperature beyond what it has ranged during the past century. Examination of larger-than-historic climatic changes that have occurred in the past in specific regions provides realistic context for evaluating such potential future changes. This paper has contrasted the climatic manifestation of the Little Climatic Optimum or Medieval Warm Period (AD 900--1300) with that of the Little Ice Age (AD 1300--1850) in the northern Colorado Plateau region of the southwestern USA. The zenith of the Anasazi occupation coincides with the former and their demise coincides with the latter, when conditions became too cold and especially dry (in the summer) to support upland dry farming. During the height of the Little Climatic Optimum the region was characterized by a relatively long growing season and greater winter and summer precipitation than that of today. This resulted in a relatively rapid development of a potential dry-farming belt that was twice as wide as the present and areas that cannot be dry farmed today were routinely farmed by the Anasazi. Such conditions would be beneficial to dry farmers in the Four Corners region if those conditions were repeated in the near future.

  2. Tree-ring dates on two pre-Little Ice Age advances in Glacier Bay National Park and Preserve, Alaska, USA (United States)

    Wiles, Gregory C.; Lawson, Daniel E.; Lyon, Eva; Wiesenberg, Nicholas; D'Arrigo, R. D.


    Two interstadial tree ring-width chronologies from Geikie Inlet, Glacier Bay Southeast, Alaska were built from 40 logs. One of these chronologies has been calendar dated to AD 224-999 (775 yr) crossdating with a living ring-width chronology from Prince William Sound, Alaska. Trees in this chronology were likely killed through inundation by sediments and meltwater from the advancing Geikie Glacier and its tributaries ca. AD 850. The earlier tree-ring chronology spans 545 yr and is a floating ring-width series tied to radiocarbon ages of about 3000 cal yr BP. This tree-ring work indicates two intervals of glacial expansion by the Geikie Glacier system toward the main trunk glacier in Glacier Bay between 3400 and 3000 cal yr BP and again about AD 850. The timing of both expansions is consistent with patterns of ice advance at tidewater glaciers in other parts of Alaska and British Columbia about the same time, and with a relative sea-level history from just outside Glacier Bay in Icy Strait. This emerging tree-ring dated history builds on previous radiocarbon-based glacial histories and is the first study to use tree-ring dating to assign calendar dates to glacial activity for Glacier Bay.

  3. The Little Ice Age was 1.0-1.5 °C cooler than current warm period according to LOD and NAO (United States)

    Mazzarella, Adriano; Scafetta, Nicola


    We study the yearly values of the length of day (LOD, 1623-2016) and its link to the zonal index (ZI, 1873-2003), the Northern Atlantic oscillation index (NAO, 1659-2000) and the global sea surface temperature (SST, 1850-2016). LOD is herein assumed to be mostly the result of the overall circulations occurring within the ocean-atmospheric system. We find that LOD is negatively correlated with the global SST and with both the integral function of ZI and NAO, which are labeled as IZI and INAO. A first result is that LOD must be driven by a climatic change induced by an external (e.g. solar/astronomical) forcing since internal variability alone would have likely induced a positive correlation among the same variables because of the conservation of the Earth's angular momentum. A second result is that the high correlation among the variables implies that the LOD and INAO records can be adopted as global proxies to reconstruct past climate change. Tentative global SST reconstructions since the seventeenth century suggest that around 1700, that is during the coolest period of the Little Ice Age (LIA), SST could have been about 1.0-1.5 °C cooler than the 1950-1980 period. This estimated LIA cooling is greater than what some multiproxy global climate reconstructions suggested, but it is in good agreement with other more recent climate reconstructions including those based on borehole temperature data.

  4. ‘Neanderthal bone flutes’: simply products of Ice Age spotted hyena scavenging activities on cave bear cubs in European cave bear dens (United States)

    Diedrich, Cajus G.


    Punctured extinct cave bear femora were misidentified in southeastern Europe (Hungary/Slovenia) as ‘Palaeolithic bone flutes’ and the ‘oldest Neanderthal instruments’. These are not instruments, nor human made, but products of the most important cave bear scavengers of Europe, hyenas. Late Middle to Late Pleistocene (Mousterian to Gravettian) Ice Age spotted hyenas of Europe occupied mainly cave entrances as dens (communal/cub raising den types), but went deeper for scavenging into cave bear dens, or used in a few cases branches/diagonal shafts (i.e. prey storage den type). In most of those dens, about 20% of adult to 80% of bear cub remains have large carnivore damage. Hyenas left bones in repeating similar tooth mark and crush damage stages, demonstrating a butchering/bone cracking strategy. The femora of subadult cave bears are intermediate in damage patterns, compared to the adult ones, which were fully crushed to pieces. Hyenas produced round–oval puncture marks in cub femora only by the bone-crushing premolar teeth of both upper and lower jaw. The punctures/tooth impact marks are often present on both sides of the shaft of cave bear cub femora and are simply a result of non-breakage of the slightly calcified shaft compacta. All stages of femur puncturing to crushing are demonstrated herein, especially on a large cave bear population from a German cave bear den. PMID:26064624

  5. Private drinking water quality in rural Wisconsin. (United States)

    Knobeloch, Lynda; Gorski, Patrick; Christenson, Megan; Anderson, Henry


    Between July 1, 2007, and December 31, 2010, Wisconsin health departments tested nearly 4,000 rural drinking water supplies for coliform bacteria, nitrate, fluoride, and 13 metals as part of a state-funded program that provides assistance to low-income families. The authors' review of laboratory findings found that 47% of these wells had an exceedance of one or more health-based water quality standards. Test results for iron and coliform bacteria exceeded safe limits in 21% and 18% of these wells, respectively. In addition, 10% of the water samples from these wells were high in nitrate and 11% had an elevated result for aluminum, arsenic, lead, manganese, or strontium. The high percentage of unsafe test results emphasizes the importance of water quality monitoring to the health of nearly one million families including 300,000 Wisconsin children whose drinking water comes from a privately owned well.

  6. Wisconsin Earth and Space Science Education (United States)

    Bilbrough, Larry (Technical Monitor); French, George


    The Wisconsin Earth and Space Science Education project successfilly met its objectives of creating a comprehensive online portfolio of science education curricular resources and providing a professional development program to increase educator competency with Earth and Space science content and teaching pedagogy. Overall, 97% of participants stated that their experience was either good or excellent. The favorable response of participant reactions to the professional development opportunities highlights the high quality of the professional development opportunity. The enthusiasm generated for using the curricular material in classroom settings was overwhelmingly positive at 92%. This enthusiasm carried over into actual classroom implementation of resources from the curricular portfolio, with 90% using the resources between 1-6 times during the school year. The project has had a positive impact on student learning in Wisconsin. Although direct measurement of student performance is not possible in a project of this kind, nearly 75% of participating teachers stated that they saw an increase in student performance in math and science as a result of using project resources. Additionally, nearly 75% of participants saw an increase in the enthusiasm of students towards math and science. Finally, some evidence exists that the professional development academies and curricular portfolio have been effective in changing educator behavior. More than half of all participants indicated that they have used more hands-on activities as a result of the Wisconsin Earth and Space Science Education project.

  7. Arctic Ice Algae Distribution as Function of Large Scale Sea Ice Variables (United States)

    Flores, H.; Castellani, G.; Lange, B. A.; David, C.; Katlein, C.; Peeken, I.; Nicolaus, M.; Losch, M. J.; van Franeker, J. A.


    One of the most pronounced impacts of climate change is the declining sea ice cover in the Arctic Ocean, which has implications for sea-ice associated ecosystems that are strongly dependent on carbon produced by ice algae. In order to understand these ecosystems there is a need to understand the interaction between the physical and biological components of sea ice. Our current understanding of Arctic sea ice algae is based on observations with limited spatial coverage. Therefore, we aim to model the spatial distribution of ice-algae on a basin scale. Current sea-ice-ocean models do allow the representation of sea-ice variability on a scale of few km. Large scale characteristics of sea ice such as age, deformation, and snow cover, do affect the small scale ice properties, such as salinity, porosity, light transmission. The latter directly affect the sea ice algae content, but to what extent is not yet well understood. In this work we present a new parameterization for the sea-ice algae content developed with the aim to model the algae content and variability based on large scale sea-ice characteristics. This parameterization is tuned with data collected during a ship-based campaign to the Eastern Central Arctic in summer 2012. Sea-ice thickness and under-ice spectral surveys over different sea ice regimes were conducted with a Surface and Under Ice Trawl (SUIT) and a Remote Operated Vehicle (ROV). In addition, ice cores were extracted at several sites for chl a analysis. We use a coupled sea-ice-ocean model with a spatial scale of 10 km and we show here the results for the temporal evolution of algae content in sea ice.

  8. A spongy icing model for aircraft icing

    Directory of Open Access Journals (Sweden)

    Li Xin


    Full Text Available Researches have indicated that impinging droplets can be entrapped as liquid in the ice matrix and the temperature of accreting ice surface is below the freezing point. When liquid entrapment by ice matrix happens, this kind of ice is called spongy ice. A new spongy icing model for the ice accretion problem on airfoil or aircraft has been developed to account for entrapped liquid within accreted ice and to improve the determination of the surface temperature when entering clouds with supercooled droplets. Different with conventional icing model, this model identifies icing conditions in four regimes: rime, spongy without water film, spongy with water film and glaze. By using the Eulerian method based on two-phase flow theory, the impinging droplet flow was investigated numerically. The accuracy of the Eulerian method for computing the water collection efficiency was assessed, and icing shapes and surface temperature distributions predicted with this spongy icing model agree with experimental results well.

  9. Carcinoma of the tongue in Norway and Wisconsin. I

    International Nuclear Information System (INIS)

    Vermund, H.


    The records of 503 patients with carcinoma of the tongue diagnosed between 1958 and 1972 were reviewed. The preponderance of tongue carcinoma among men was confirmed both in The Norwegian Radium Hospital (NRH) and the University of Wisconsin Hospitals (UW), but it was relatively more frequent among women in NRH and in UW than in southern Europe. More women had on presentation less advanced tumors at NRH than at UW. The incidence of tongue carcinoma in Norway increased steadily with age for both sexes. The sex ratio did not change in Norway such as in England, Canada and the United States. Tumor of the posterior one-third of the tongue was relatively infrequent in women both in NRH and UW, in agreement with reports from other countries. The length of survival was analysed and no significant sex difference was demonstrated. The younger patients had less advanced tumors and a better prognosis. (Auth.)

  10. Adolescent IQ and Survival in the Wisconsin Longitudinal Study (United States)

    Hauser, Robert M.; Palloni, Alberto


    Objective. This study attempts to explain the ubiquitous positive correlation between cognitive ability (IQ) and survival. Methods. A sample of 10,317 Wisconsin high school graduates of 1957 was followed until 2009, from ages 18 to 68 years. Mortality was analyzed using a Weibull survival model that includes gender, social background, Henmon–Nelson IQ, and rank in high school class. Results. Rank in high school class, a cumulative measure of responsible performance during high school, entirely mediates the relationship between adolescent IQ and survival. Its effect on survival is 3 times greater than that of IQ, and it accounts for about 10% of the female advantage in survival. Discussion. Cognitive functioning may improve survival by promoting responsible and timely patterns of behavior that are firmly in place by late adolescence. Prior research suggests that conscientiousness, one of the “Big Five” personality characteristics, plays a key role in this relationship. PMID:21743056

  11. There goes the sea ice: following Arctic sea ice parcels and their properties. (United States)

    Tschudi, M. A.; Tooth, M.; Meier, W.; Stewart, S.


    Arctic sea ice distribution has changed considerably over the last couple of decades. Sea ice extent record minimums have been observed in recent years, the distribution of ice age now heavily favors younger ice, and sea ice is likely thinning. This new state of the Arctic sea ice cover has several impacts, including effects on marine life, feedback on the warming of the ocean and atmosphere, and on the future evolution of the ice pack. The shift in the state of the ice cover, from a pack dominated by older ice, to the current state of a pack with mostly young ice, impacts specific properties of the ice pack, and consequently the pack's response to the changing Arctic climate. For example, younger ice typically contains more numerous melt ponds during the melt season, resulting in a lower albedo. First-year ice is typically thinner and more fragile than multi-year ice, making it more susceptible to dynamic and thermodynamic forcing. To investigate the response of the ice pack to climate forcing during summertime melt, we have developed a database that tracks individual Arctic sea ice parcels along with associated properties as these parcels advect during the summer. Our database tracks parcels in the Beaufort Sea, from 1985 - present, along with variables such as ice surface temperature, albedo, ice concentration, and convergence. We are using this database to deduce how these thousands of tracked parcels fare during summer melt, i.e. what fraction of the parcels advect through the Beaufort, and what fraction melts out? The tracked variables describe the thermodynamic and dynamic forcing on these parcels during their journey. This database will also be made available to all interested investigators, after it is published in the near future. The attached image shows the ice surface temperature of all parcels (right) that advected through the Beaufort Sea region (left) in 2014.

  12. Medieval climate anomaly and little ice age as recorded in speleothem and tree-ring data from the Middle Atlas in Morocco (United States)

    Wassenburg, J. A.; Immenhauser, A.; Richter, D. K.; Fietzke, J.; Scholz, D.; Jochum, K. P.; Riechelmann, D. F. C.; Schneider, L.; Esper, J.


    Progress has recently been made in assessing the spatial extend and timing of the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA) on hemispheric and global scales (Graham et al. 2011). Uncertainties still exist, however, since the transition from the MCA into the LIA seems to be diachronous, and in many cases, reconstructions are based on single climate archives (e.g., speleothems, tree-rings, or pollen data). In Morocco, cedar trees from the Middle and High Atlas have been used to reconstruct the Palmer Drought Severity Index (PDSI) back to 1049 AD (Esper et al., 2007), a metric integrating the evaporation-precipitation balance and soil properties. According to Graham et al. (2011), the MCA/LIA transition recorded in Moroccan tree rings occurred rather late (around 1400 AD) in comparison to the reconstructed winter temperature in the European Alps (e.g., Mangini et al., 2005), which show substantial changes about 50 years earlier. Here we compare precisely dated speleothem δ13C and trace element records from the Middle Atlas with an updated version of the tree-ring based PDSI reconstruction from Esper et al. (2007). Both stalagmite δ13C and strontium records support the prevalence of exceptionally dry conditions during the MCA and relatively wet conditions during the LIA. These changes have formerly been suggested to be related to persistent positive and negative phases of the North Atlantic Oscillation (Trouet et al., 2009). The speleothem based reconstruction extends back to 700 AD and, thus, provides insight on the precise timing of the driest period during the MCA in the Moroccan Middle Atlas.

  13. High-resolution lake sediment archives of midcontinental atmospheric and hydroclimate variability during the Medieval Climate Anomaly and Little Ice Age (United States)

    Bird, B. W.; Wilson, J. J.; Gilhooly, W., III; Steinman, B. A.; Stamps, L. G.; Ahmed, M. N.; Abbott, M. B.; Pompeani, D. P.; Hillman, A. L.; Finkenbinder, M. S.


    Hydroclimate variability in the midcontinental United States (US) during the last 2000 years is not well characterized because there are few high-resolution paleoclimate records from the region. The majority of information about late Holocene midcontinental hydroclimate variability comes from scattered lake and bog sediment archives (primarily north of 42˚N) and gridded Palmer Drought Severity Index (PDSI) data calculated from a network of tree-ring records. The density of tree-ring records is lowest in the midcontinent, however, and decreases precipitously with time. In order to address this midcontinental paleoclimate data gap, we are developing a series of new lake-sediment-based hydroclimate records spanning 85˚ to 98˚W and 38˚ to 45˚N. New results from the eastern and central portions of the study area indicate large hydroclimate changes during the last 2000 years. Specifically, the Ohio and central Mississippi River valleys were wetter during the Medieval Climate Anomaly (MCA; 950-1250 CE), but drier during the Little Ice Age (LIA; 1350-1850 CE) with an especially severe, multi-decadal drought between 1350-1450 CE. Comparison with western (west of 96˚W) drought and fire records supports the existence of a hydroclimate dipole, with opposite hydroclimate conditions west and east of 96˚W. Isotopic changes in precipitation during the MCA and LIA suggest hydroclimate anomalies during these events were associated with mean state atmospheric circulation changes that resemble modern Pacific North American Mode (PNA) variability. Midcontinental Native American populations appear to have responded to MCA and LIA hydroclimate variability, with the latter event contributing to midcontinental depopulation between 1350-1500 CE.

  14. Phylogeographic and population insights of the Asian common toad (Bufo gargarizans in Korea and China: population isolation and expansions as response to the ice ages

    Directory of Open Access Journals (Sweden)

    Amaël Borzée


    Full Text Available The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad (Bufo gargarizans from South Korea and their North East Asian counterpart populations, based on mitochondrial data. Korean B. gargarizans GenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.. Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a

  15. Phylogeographic and population insights of the Asian common toad (Bufo gargarizans) in Korea and China: population isolation and expansions as response to the ice ages. (United States)

    Borzée, Amaël; Santos, Joana L; Sánchez-RamÍrez, Santiago; Bae, Yoonhyuk; Heo, Kyongman; Jang, Yikweon; Jowers, Michael Joseph


    The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad ( Bufo gargarizans ) from South Korea and their North East Asian counterpart populations, based on mitochondrial data. Korean B. gargarizans GenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.). Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a., likely attributed

  16. A comparison of the climates of the Medieval Climate Anomaly, Little Ice Age, and Current Warm Period reconstructed using coral records from the northern South China Sea (United States)

    Deng, Wenfeng; Liu, Xi; Chen, Xuefei; Wei, Gangjian; Zeng, Ti; Xie, Luhua; Zhao, Jian-xin


    For the global oceans, the characteristics of high-resolution climate changes during the last millennium remain uncertain because of the limited availability of proxy data. This study reconstructs climate conditions using annually resolved coral records from the South China Sea (SCS) to provide new insights into climate change over the last millennium. The results indicate that the climate of the Medieval Climate Anomaly (MCA, AD 900-1300) was similar to that of the Current Warm Period (CWP, AD 1850-present), which contradicts previous studies. The similar warmth levels for the MCA and CWP have also been recorded in the Makassar Strait of Indonesia, which suggests that the MCA was not warmer than the CWP in the western Pacific and that this may not have been a globally uniform change. Hydrological conditions were drier/saltier during the MCA and similar to those of the CWP. The drier/saltier MCA and CWP in the western Pacific may be associated with the reduced precipitation caused by variations in the Pacific Walker Circulation. As for the Little Ice Age (LIA, AD 1550-1850), the results from this study, together with previous data from the Makassar Strait, indicate a cold and wet period compared with the CWP and the MCA in the western Pacific. The cold LIA period agrees with the timing of the Maunder sunspot minimum and is therefore associated with low solar activity. The fresher/wetter LIA in the western Pacific may have been caused by the synchronized retreat of both the East Asian Summer Monsoon and the Australian Monsoon.

  17. A new little ice age?

    International Nuclear Information System (INIS)

    Labohm, H.


    According to the IPCC (Intergovernmental Panel on Climate Change) climatic change is caused by humans, in particular the emission of CO2 as a result of combustion of fossil fuels. However, according to the author this has not been proved beyond the shadow of doubt. Climatic change sceptics even consider it as unlikely. They believe that the heating up of the last 150 years (circa 0.7C) has mainly natural causes [nl

  18. Elements of Instruction VTAE Workshop (Wisconsin Rapids, Wisconsin, March 7-9, 1989). Final Report. (United States)

    Lee, Howard D.

    This document describes a 3-day Wisconsin workshop on essential elements of instruction in vocational, technical, and adult education (VTAE). The workshop's content was based on the Univesity of California at Los Angeles' Teaching Model, which resulted from the work of Madeline Hunter. A three-page narrative describes some aspects of the model,…

  19. Quality of Wisconsin stormwater, 1989-94 (United States)

    Bannerman, Roger T.; Legg, Andrew D.; Greb, Steven R.


    Water-quality data were compiled from four urban stormwater monitoring projects conducted in Wisconsin between 1989 and 1994. These projects included monitoring in both storm-sewer pipes and urban streams. A total of 147 constitu ents were analyzed for in stormwater sampled from 10 storm-sewer pipes and four urban streams. Land uses represented by the storm-sewer watersheds included residential, commercial, industrial, and mixed. For about one-half the con stituents, at least 10 percent of the event mean con centrations exceeded the laboratory's minimum reporting limit. Detection frequencies were greater than 75 percent for many of the heavy metals and polycyclic aromatic hydrocarbons in both the storm sewer and stream samples, whereas detec tion frequencies were about 20 percent or greater for many of the pesticides in both types of sam ples. Stormwater concentrations for conventional constituents, such as suspended solids, chloride, total phosphorus, and fecal coliform bacteria were greater than minimum reporting limits almost 100 percent of the time. Concentrations of many of the constituents were high enough to say that stormwater in the storm sewers and urban streams might be contrib uting to the degradation of the streams. In this report, constituents defined as potential contami nants are those for which the laboratory minimum report limit was exceeded for at least 10 percent of the sampled storm events, and for which at least one event mean concentration exceeded an estab lished water-quality standard. Storm-sewer sam ples had event mean concentrations of lead, copper, zinc, cadmium, and silver that frequently exceeded Wisconsin's acute toxicity criteria for cold water fisheries. Wisconsin's human cancer criteria was exceeded almost 100 percent of the time for polycyclic aromatic hydrocarbons in stormwater samples from storm sewers and streams. Maximum concentrations of diazinon found in storm sewers exceeded recommended levels of diazinon. Storm

  20. Similar performance of Brasfield and Wisconsin scoring systems in young children with cystic fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Cleveland, Robert H.; Stamoulis, Catherine [Boston Children' s Hospital, Harvard Medical School, Department of Radiology, Boston, MA (United States); Sawicki, Gregory S. [Boston Children' s Hospital, Harvard Medical School, Division of Respiratory Diseases, Department of Medicine, Boston, MA (United States)


    To assess the severity of lung disease in cystic fibrosis (CF), scoring systems based on chest radiographs (CXRs), CT and MRI have been used extensively, although primarily in research settings rather than for clinical purposes. It has recently been shown that those based on CXRs (primarily the Brasfield and Wisconsin systems) are as sensitive and valid as those based on CT. The reproducibility and correlation of both systems to pulmonary function tests (PFTs) were recently investigated and were found to be statistically identical. However, the relative performance of these systems has not been specifically assessed in children younger than 5 years old with mild lung disease, a critical age range in which PFTs is rarely performed. To investigate and compare the performance of the Brasfield and Wisconsin systems in children 0-5 years old with predominantly mild lung disease. Fifty-five patients 0-5 years old with 105 CXRs were included in the study. Given that the goal was to compare system performance in mild disease, only the first two CXRs from each patient were included (all but five patients had two images). When only one image was available in the target age range, it only was included. Agreement between the Brasfield and Wisconsin systems was assessed using a 2X2 contingency table assuming binary classification of CF lung disease using CXR scoring systems (mild vs. non-mild). In the absence of PFTs or another external gold standard for comparison, the Wisconsin system was used as an arbitrary gold standard against which the Brasfield was compared. Correlation between the two systems was assessed via a concordance correlation coefficient (CCC) for repeated measures. Scores were rated as mild or non-mild based on published numerical cutoffs for each system. The systems agreed on 89/105 (85%) and disagreed on 16/105 (15%) of the CXRs. Agreement between the two systems was statistically significant (P < 0.001). Relative sensitivity and specificity of the

  1. Mixing zones studies of the waste water discharge from the Consolidated Paper Company into the Wisconsin River at Wisconsin Rapids, Wisconsin (United States)

    Hoopes, J. A.; Wu, D. S.; Ganatra, R.


    Effluent concentration distributions from the waste water discharge of the Kraft Division Mill, Consolidated Paper Company, into the Wisconsin River at Wisconsin Rapids, Wisconsin, is investigated. Effluent concentrations were determined from measurements of the temperature distribution, using temperature as a tracer. Measurements of the velocity distribution in the vicinity of the outfall were also made. Due to limitations in the extent of the field observations, the analysis and comparison of the measurements is limited to the region within about 300 feet from the outfall. Effects of outfall submergence, of buoyancy and momentum of the effluent and of the pattern and magnitude of river currents on these characteristics are considered.

  2. Ice cores and palaeoclimate

    International Nuclear Information System (INIS)

    Krogh Andersen, K.; Ditlevsen, P.; Steffensen, J.P.


    Ice cores from Greenland give testimony of a highly variable climate during the last glacial period. Dramatic climate warmings of 15 to 25 deg. C for the annual average temperature in less than a human lifetime have been documented. Several questions arise: Why is the Holocene so stable? Is climatic instability only a property of glacial periods? What is the mechanism behind the sudden climate changes? Are the increased temperatures in the past century man-made? And what happens in the future? The ice core community tries to attack some of these problems. The NGRIP ice core currently being drilled is analysed in very high detail, allowing for a very precise dating of climate events. It will be possible to study some of the fast changes on a year by year basis and from this we expect to find clues to the sequence of events during rapid changes. New techniques are hoped to allow for detection of annual layers as far back as 100,000 years and thus a much improved time scale over past climate changes. It is also hoped to find ice from the Eemian period. If the Eemian layers confirm the GRIP sequence, the Eemian was actually climatically unstable just as the glacial period. This would mean that the stability of the Holocene is unique. It would also mean, that if human made global warming indeed occurs, we could jeopardize the Holocene stability and create an unstable 'Eemian situation' which ultimately could start an ice age. Currenlty mankind is changing the composition of the atmosphere. Ice cores document significant increases in greenhouse gases, and due to increased emissions of sulfuric and nitric acid from fossil fuel burning, combustion engines and agriculture, modern Greenland snow is 3 - 5 times more acidic than pre-industrial snow (Mayewski et al., 1986). However, the magnitude and abruptness of the temperature changes of the past century do not exceed the magnitude of natural variability. It is from the ice core perspective thus not possible to attribute the

  3. Flood-frequency characteristics of Wisconsin streams (United States)

    Walker, John F.; Peppler, Marie C.; Danz, Mari E.; Hubbard, Laura E.


    Flood-frequency characteristics for 360 gaged sites on unregulated rural streams in Wisconsin are presented for percent annual exceedance probabilities ranging from 0.2 to 50 using a statewide skewness map developed for this report. Equations of the relations between flood-frequency and drainage-basin characteristics were developed by multiple-regression analyses. Flood-frequency characteristics for ungaged sites on unregulated, rural streams can be estimated by use of the equations presented in this report. The State was divided into eight areas of similar physiographic characteristics. The most significant basin characteristics are drainage area, soil saturated hydraulic conductivity, main-channel slope, and several land-use variables. The standard error of prediction for the equation for the 1-percent annual exceedance probability flood ranges from 56 to 70 percent for Wisconsin Streams; these values are larger than results presented in previous reports. The increase in the standard error of prediction is likely due to increased variability of the annual-peak discharges, resulting in increased variability in the magnitude of flood peaks at higher frequencies. For each of the unregulated rural streamflow-gaging stations, a weighted estimate based on the at-site log Pearson type III analysis and the multiple regression results was determined. The weighted estimate generally has a lower uncertainty than either the Log Pearson type III or multiple regression estimates. For regulated streams, a graphical method for estimating flood-frequency characteristics was developed from the relations of discharge and drainage area for selected annual exceedance probabilities. Graphs for the major regulated streams in Wisconsin are presented in the report.

  4. Archaeological Investigations at a Wisconsin Petroglyph Site

    Directory of Open Access Journals (Sweden)

    Jack Steinbring


    Full Text Available Preliminary test excavations at the Hensler Petroglyph Site in East Central Wisconsin, U.S.A. have disclosed the remains of aboriginal engravings below Aeolian sediments dated to ca. 15,000 years B.P. The stratified deposits lying adjacent to an engraved panel, containing 35 pecked images, have yielded animal-like cobbles, some covered with red ochre, apparently picked for some esoteric use. The site itself has unusual natural shapes in the rock formation, along with acoustical properties, lightning strikes, a magnetic anomaly, and geographic prominence. Collectively these factors are thought to have attracted the ancient rock artists to the site.

  5. Lake Malawi sediment and pore water chemistry: Proposition of a conceptual model for stratification intensification since the end of the Little Ice Age (United States)

    Branchu, Philippe; Bergonzini, Laurent; Pons-branchu, Edwige; Violier, Eric; Dittrich, Maria; Massault, Marc; Ghaleb, Bassam


    Sedimentary records of salinity indicators are largely used to reconstruct past climatic changes in lacustrine systems where chemistry is sensitive to hydroclimatic conditions. In large fresh lakes of the East African Rift such as Lakes Tanganyika and Malawi, salinity is often considered constant and other paleoclimatological proxy data are used. However, a relation between lake surface chloride concentration and hydroclimatic regime was previously demonstrated at the century scale in Lake Tanganyika. This relation is transposed to Lake Malawi on the base of similarity between hydrochemical budgets of both lakes that are computed for the whole lake and epilimnion. Whereas numerous physico-chemical difficulties make generally debatable use of lake pore water chemistry, as illustrated here by diffusion modelling, the dissolved chloride concentration profile from a core sampled in northern Lake Malawi is considered as a potential indicator of limnological-hydroclimatic condition changes for the last 200 years. A decrease in pore water chloride concentration between 1840 AD and present situation is directly associated to a metalimnetic water salinity decrease. The chronology of this event is synchronous with diatom productivity change demonstrated by Johnson et al. (2001) at the end of the Little Ice Age (LIA). A conceptual model of Lake Malawi, based on salinity, organic carbon and its "dead" watershed contribution, lake-level and productivity changes since the mid 19th century is presented. A new scenario is proposed, based on thermal stratification reinforcement at the end of the LIA. Lake productivity and chemistry depend on stratification strength, water column mixing rate and on climatic variability. During the LIA, nutrient distribution profiles were more homogeneous with depth due to the climatically (colder and drier climatic conditions than today) induced destabilisation of the mixing barrier. The productive system is then auto-supplied and does not require

  6. Place vs. time and vegetational persistence: A comparison of four tropical mires from the Illinois Basin during the height of the Pennsylvanian Ice Age (United States)

    DiMichele, W.A.; Phillips, T.L.; Nelson, W. John


    Coal balls were collected from four coal beds in the southeastern part of the Illinois Basin. Collections were made from the Springfield, Herrin, and Baker coals in western Kentucky, and from the Danville Coal in southwestern Indiana. These four coal beds are among the principal mineable coals of the Illinois Basin and belong to the Carbondale and Shelburn Formations of late Middle Pennsylvanian age. Vegetational composition was analyzed quantitatively. Coal-ball samples from the Springfield, Herrin, and Baker are dominated by the lycopsid tree Lepidophloios, with lesser numbers of Psaronius tree ferns, medullosan pteridosperms, and the lycopsid trees Synchysidendron and Diaphorodendron. This vegetation is similar to that found in the Springfield and Herrin coals elsewhere in the Illinois Basin, as reported in previous studies. The Danville coal sample, which is considerably smaller than the others, is dominated by Psaronius with the lycopsids Sigillaria and Synchysidendron as subdominants. Coal balls from the Springfield coal were collected in zones directly from the coal bed and their zone-by-zone composition indicates three to four distinct plant assemblages. The other coals were analyzed as whole-seam random samples, averaging the landscape composition of the parent mire environments. This analysis indicates that these coals, separated from each other by marine and terrestrial-clastic deposits, have essentially the same floristic composition and, thus, appear to represent a common species pool that persisted throughout the late Middle Pennsylvanian, despite changes in baselevel and climate attendant the glacial interglacial cyclicity of the Pennsylvanian ice age. Patterns of species abundance and diversity are much the same for the Springfield, Herrin, and Baker, although each coal, both in the local area sampled, and regionally, has its own paleobotanical peculiarities. Despite minor differences, these coals indicate a high degree of recurrence of assemblage

  7. Wisconsin EE Mandates: The Bad News and the Good News. (United States)

    Lane, Jennie; And Others


    Examines Wisconsin teachers' perceived competencies in, attitudes toward, and amount of class time devoted to teaching about the environment. Discusses the effects of Wisconsin environmental education mandates concerning preservice preparation in environmental education and K-12 environmental education curriculum plans. Identifies areas where the…

  8. Wisconsin Maternity Leave and Fringe Benefits: Policies, Practices and Problems. (United States)

    Gerner, Jennifer

    The study examines the economic implications in Wisconsin of the 1972 Equal Employment Opportunity Commission guideline which requires employers to treat maternity leave as a temporary disability. First, the static cost of the maternity leave guideline to employers is estimated for the State of Wisconsin. Second, some examination of the economic…

  9. Sea ice - Multiyear cycles and white ice (United States)

    Ledley, T. S.


    The multiyear thickness cycles represent one of the interesting features of the sea ice studies performed by Semtner (1976) and Washington et al. (1976) with simple thermodynamic models of sea ice. In the present article, a description is given of results which show that the insulating effect of snow on the surface of the sea ice is important in producing these multiyear cycles given the physics included in the model. However, when the formation of white ice is included, the cycles almost disappear. White ice is the ice which forms at the snow-ice interface when the snow layer becomes thick enough to depress the ice below the water level. Water infiltrates the snow by coming through the ice at leads and generally freezes there, forming white ice.

  10. Age (United States)

    ... Resources About Policymakers Media ASA Member Toolkit Risks Age Explore this page: Age Do anesthesia risks increase ... can you reduce anesthesia risks in older patients? Age Age may bring wisdom but it also brings ...

  11. Sediment Mixing in the Holocene and Late Wisconsin Mississippi Source-To System Using Detrital Zircons (United States)

    Mason, C. C.; Fildani, A.; Gerber, T. P.; Blum, M. D.; Clark, J. D.; Dykstra, M.


    U-Pb geochronology of detrital zircons (DZ) is a robust tool used to elucidate linkages between tectonics, climate, drainage configurations, and sediment provenance. The late Pleistocene to modern Mississippi drainage basin has experienced modifications by glacial ice and recent anthropogenic modifications, making it an ideal natural laboratory for sedimentary system response to forcings over different timescales. DZs in the lower Mississippi Valley, delta, and deep-sea fan reflect time-integrated (103-4 yrs) pre-anthropogenic contributions from large tributary catchments. Here we present results of DZ mixture modeling using modern sediment samples from tributaries as parent components, and samples from the modern lower Mississippi River and delta, and late Wisconsin deep-sea fan (marine isotope stage 2; DSDP 96 cores) as daughter mixtures. Mixture modeling of modern daughter samples shows broad agreement between modeled relative contributions and measured suspended sediment loads (1976-2009). Differences between model results and historical records can best be explained by anthropogenic sediment impoundment within tributaries to the lower Mississippi. Modeling of late Wisconsin deep-sea daughter samples indicates the Missouri and Upper Mississippi river basins supplied >95% of the sediment to the late Wisconsin deep-sea fan. We interpret these results in terms of increased sediment supply during the last glacial maximum, and increased transport capacity related to deglacial melt-water floods. We suggest sediment composition in large rivers responds to icehouse climate change at timescales of 103-4 years, in contrast to indications that anthropogenic river modifications can alter sediment flux nearly instantaneously. Furthermore, adjustments in lower Mississippi River, delta, and deep-sea fan mixtures occur at timescales an order-of-magnitude less than Milankovitch-scale climate changes, or the equilibrium response time of the Mississippi River itself, indicating

  12. Diversity of cultured bacteria from the perennial ice block of Scarisoara Ice Cave, Romania

    Directory of Open Access Journals (Sweden)

    Corina Iţcuş


    Full Text Available Cave ice ecosystems represent a poorly investigated glacial environment. Diversity of cave ice bacteria and their distribution in perennial ice deposits of this underground glacial habitat could constitute a proxy for microbial response to climatic and environmental changes. Scarisoara Ice Cave (Romania hosts one of the oldest and largest cave ice blocks worldwide. Here we report on cultured microbial diversity of recent, 400, and 900 years-old perennial ice from this cave, representing the first characterization of a chronological distribution of cave-ice bacteria. Total cell density measured by SYBR Green I epifluorescence microscopy varied in the 2.4 x 104 – 2.9 x 105 cells mL-1 range. The abundance of cultured bacteria (5 x 102 – 8 x 104 CFU mL-1 representing 0.3-52% of the total cell number decreased exponentially with the ice age, and was higher in organic rich ice sediments. Cultivation at 4˚C and 15˚C using BIOLOG EcoPlates revealed a higher functional diversity of cold-active bacteria, dependent on the age, sediment content and physicochemical properties of the ice. The composition dissimilarity of ice microbiota across the ice block was confirmed by growth parameter variations when cultivated in different liquid media at low and high temperatures. PCR-DGGE and sequencing of bacterial 16S rRNA gene fragments from the cultured ice samples led to the identification of 77 bacterial amplicons belonging to Gammaproteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, showing variation in distribution across the ice layers. Several identified OTUs were homologous to those identified in other glacial and karst environments and showed partial conservation across the ice block. Moreover, our survey provided a glimpse on the cave-ice hosted bacteria as putative biomarkers for past climate and environmental changes.

  13. Methane Isotopes from the WAIS Divide Ice Core, Version 1 (United States)

    National Aeronautics and Space Administration — This data set includes methane (CH4) isotope data from the West Antarctic Ice Sheet (WAIS) Divide ice core, WDC05A, in Antarctica. The data include depth, gas age,...

  14. Dendroclimatic transfer functions revisited: Little Ice Age and Medieval Warm Period summer temperatures reconstructed using artificial neural networks and linear algorithms

    Directory of Open Access Journals (Sweden)

    S. Helama


    Full Text Available Tree-rings tell of past climates. To do so, tree-ring chronologies comprising numerous climate-sensitive living-tree and subfossil time-series need to be "transferred" into palaeoclimate estimates using transfer functions. The purpose of this study is to compare different types of transfer functions, especially linear and nonlinear algorithms. Accordingly, multiple linear regression (MLR, linear scaling (LSC and artificial neural networks (ANN, nonlinear algorithm were compared. Transfer functions were built using a regional tree-ring chronology and instrumental temperature observations from Lapland (northern Finland and Sweden. In addition, conventional MLR was compared with a hybrid model whereby climate was reconstructed separately for short- and long-period timescales prior to combining the bands of timescales into a single hybrid model. The fidelity of the different reconstructions was validated against instrumental climate data. The reconstructions by MLR and ANN showed reliable reconstruction capabilities over the instrumental period (AD 1802–1998. LCS failed to reach reasonable verification statistics and did not qualify as a reliable reconstruction: this was due mainly to exaggeration of the low-frequency climatic variance. Over this instrumental period, the reconstructed low-frequency amplitudes of climate variability were rather similar by MLR and ANN. Notably greater differences between the models were found over the actual reconstruction period (AD 802–1801. A marked temperature decline, as reconstructed by MLR, from the Medieval Warm Period (AD 931–1180 to the Little Ice Age (AD 1601–1850, was evident in all the models. This decline was approx. 0.5°C as reconstructed by MLR. Different ANN based palaeotemperatures showed simultaneous cooling of 0.2 to 0.5°C, depending on algorithm. The hybrid MLR did not seem to provide further benefit above conventional MLR in our sample. The robustness of the conventional MLR over the

  15. The deglaciation of Iztaccíhuatl volcano (Mexico) from the Little Ice Age maximum to the present, determined by photogrametry and lichenometry (United States)

    Palacios, D.; García-Sancho, L.; Zamorano, J. J.; Andrés, N.; Pintado, A.


    Iztaccíhualt Volcano (19°10'20''N, 98°38'30''W, 5230 m asl) preserves an important moraine complex from the Little Ice Age (LIA), which stretches to 4300 m asl. These moraines are different from former ones because they are not covered by ash fall from the last plinian explosive phases of the nearby Popocatépetl volcano. In fact, the last emission of those pyroclasts took place during the XI century (Vázquez-Selem, 2000). The summit area of the Iztaccíhualt volcano still has glaciers whose terminus are located around 5000 m asl. From the end of the LIA until present the glacier terminus have ascended 700 m. To study the deglaciation process in Iztaccíhualt volcano from the LIA maximum to present, the Ayoloco valley was selected as it is the most important valley of the western slope of the volcano. Taking this valley as a reference, we determined the limits of glaciers in different dates by georeferencing the aerial and panoramic photographs (from 1897 to 2000) and analysing the 1958 field cartography of the glacial limits (Lorenzo, 1964). On the one hand, we carried out a statistical analysis of the size of the Rhizocarpon geographicum thallus and, on the other hand, we undertook a statistical study of the biodiversity of the lichen species through a number of cross-sections from the lowest LIA moraines to the current glacier snouts. This methodology allowed dating the exact moment in which the glacier retreated over certain points of the analysed cross-sections and determining the ecesis and the growth curve of the Rhizocarpon geographicum specie. In the Ayoloco valley the average growth rate is of 0.23 mm per year. From this information, we could deduce the evolution of the glacier from the LIA maximum to present. The results indicate that two main advances took place during the XVII and the XIX centuries. At the beginning of the XX century the glacier terminus were very close to the moraines of the maximum advance. An intense glacial retreat took place

  16. Variation in the Asian monsoon intensity and dry-wet condition since the Little Ice Age in central China revealed by an aragonite stalagmite (United States)

    Yin, J.-J.; Yuan, D.-X.; Li, H.-C.; Cheng, H.; Li, T.-Y.; Edwards, R. L.; Lin, Y.-S.; Qin, J.-M.; Tang, W.; Zhao, Z.-Y.; Mii, H.-S.


    Highlight: this paper focuses on the climate variability in central China since 1300 AD, involving: 1. A well-dated, 1.5 year resolution stalagmite δ18O record from Lianhua Cave, central China; 2. Links of the δ18O record with regional dry-wet condition, monsoon intensity, and temperature over eastern China; 3. Correlations among drought events in the Lianhua record, solar irradiation, and ENSO index. We present a highly precisely 230Th/U dated, 1.5 year resolution δ18O record of an aragonite stalagmite (LHD1) collected from Lianhua Cave in Wuling mountain area of central China. The comparison of the δ18O record with the local instrumental record and historical documents exhibits at least 15 drought events in the Wuling mountain and adjacent areas during the Little Ice Age, in which some of them were corresponding to megadrought events in the broad Asian monsoonal region of China. Thus, the stalagmite δ18O record reveals variations in the summer monsoon precipitation and dry-wet condition in Wuling mountain area. The eastern China temperature varied with the solar activity, showing higher temperature under stronger solar irradiation which produces stronger summer monsoon. During Maunder, Dalton and 1900 sunspot minima, more severe drought events occurred, indicating weakening of the summer monsoon when solar activity decreased on decadal time scales. On interannual time scale, dry conditions in the studying area were prevailing under El Niño condition, which is also supported by the spectrum analysis. Hence, our record illustrates the linkage of Asian summer monsoon precipitation to solar irradiation and ENSO: wetter condition under stronger summer monsoon during warm periods and vice versa; During cold periods, the Walker circulation will shift toward central Pacific under El Niño condition, resulting further weakening of Asian summer monsoon. However, the δ18O of LHD1 record is positively correlated with temperature after ~1940 AD which is opposite to the

  17. Cold-season patterns of reserve and soluble carbohydrates in sugar maple and ice-damaged trees of two age classes following drought (United States)

    B. L. Wong; K. L. Baggett; A. H. Rye


    This study examines the effects of summer drought on the composition and profiles of cold-season reserve and soluble carbohydrates in sugar maple (Acer saccharum Marsh.) trees (50-100 years old or ~200 years old) in which the crowns were nondamaged or damaged by the 1998 ice storm. The overall cold season reserve...

  18. Groundwater Quantity and Quality Issues in a Water-Rich Region: Examples from Wisconsin, USA

    Directory of Open Access Journals (Sweden)

    John Luczaj


    Full Text Available The State of Wisconsin is located in an unusually water-rich portion of the world in the western part of the Great Lakes region of North America. This article presents an overview of the major groundwater quantity and quality concerns for this region in a geologic context. The water quantity concerns are most prominent in the central sand plain region and portions of a Paleozoic confined sandstone aquifer in eastern Wisconsin. Water quality concerns are more varied, with significant impacts from both naturally occurring inorganic contaminants and anthropogenic sources. Naturally occurring contaminants include radium, arsenic and associated heavy metals, fluoride, strontium, and others. Anthropogenic contaminants include nitrate, bacteria, viruses, as well as endocrine disrupting compounds. Groundwater quality in the region is highly dependent upon local geology and land use, but water bearing geologic units of all ages, Precambrian through Quaternary, are impacted by at least one kind of contaminant.

  19. Off-Ice Anaerobic Power Does Not Predict On-Ice Repeated Shift Performance in Hockey. (United States)

    Peterson, Ben J; Fitzgerald, John S; Dietz, Calvin C; Ziegler, Kevin S; Baker, Sarah E; Snyder, Eric M


    Peterson, BJ, Fitzgerald, JS, Dietz, CC, Ziegler, KS, Baker, SE, and Snyder, EM. Off-ice anaerobic power does not predict on-ice repeated shift performance in hockey. J Strength Cond Res 30(9): 2375-2381, 2016-Anaerobic power is a significant predictor of acceleration and top speed in team sport athletes. Historically, these findings have been applied to ice hockey although recent research has brought their validity for this sport into question. As ice hockey emphasizes the ability to repeatedly produce power, single bout anaerobic power tests should be examined to determine their ability to predict on-ice performance. We tested whether conventional off-ice anaerobic power tests could predict on-ice acceleration, top speed, and repeated shift performance. Forty-five hockey players, aged 18-24 years, completed anthropometric, off-ice, and on-ice tests. Anthropometric and off-ice testing included height, weight, body composition, vertical jump, and Wingate tests. On-ice testing consisted of acceleration, top speed, and repeated shift fatigue tests. Vertical jump (VJ) (r = -0.42; r = -0.58), Wingate relative peak power (WRPP) (r = -0.32; r = -0.43), and relative mean power (WRMP) (r = -0.34; r = -0.48) were significantly correlated (p ≤ 0.05) to on-ice acceleration and top speed, respectively. Conversely, none of the off-ice tests correlated with on-ice repeated shift performance, as measured by first gate, second gate, or total course fatigue; VJ (r = 0.06; r = 0.13; r = 0.09), WRPP (r = 0.06; r = 0.14; r = 0.10), or WRMP (r = -0.10; r = -0.01; r = -0.01). Although conventional off-ice anaerobic power tests predict single bout on-ice acceleration and top speed, they neither predict the repeated shift ability of the player, nor are good markers for performance in ice hockey.

  20. Mars, earth, and ice

    International Nuclear Information System (INIS)

    Cordell, B.M.


    Possible mechanisms to explain the global ice covering of Mars, and previous ice ages on the earth, are considered. Evidence for the Milankovitch effect is found in the close correspondence of earth's past climate with its orbital variations, as recorded principally in ocean sediments, and the role of CO 2 is discussed. Mars' range of obliquity, 10 times that of the earth, and orbital eccentricity, fluctuating over a range 2 1/2 times that of the earth, could produce an important climate-driving cycle. Mathematical models of the Martian surface and atmosphere based on Viking data suggest that escaped CO 2 could create a surface pressure of 1-3 bars. Other factors such as the effect of continental drift, the increased brightness of the sun, and planetary reversals of magnetic field polarity are discussed, and the questions of where Martian water and CO 2 have gone are considered

  1. Wisconsin River at Portage, Wisconsin; Feasibility Study for Flood Control Plant of Study. (United States)


    natural setting that the late Aldo Leopold , often called the "Father of Wildlife Management," wrote some of his famous works in the still-standing log...Protect endangered or threatened plants and animals and their ha>itats. e. Consider the Aldo Leopold Memorial Reserve. The Wisconsin Department of Natural...standing log cabin he built -- that the late 0 0 Aldo Leopold wrote some of his famous works. He also wrote about this very site and the immediate area

  2. Great Lakes Ice Charts (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Charts show ice extent and concentration three times weekly during the ice season, for all lakes except Ontario, from the 1973/74 ice season through the 2001/2002...

  3. Holocene accumulation and ice flow near the West Antarctic Ice Sheet Divide ice core site (United States)

    Koutnik, Michelle R.; Fudge, T. J.; Conway, Howard; Waddington, Edwin D.; Neumann, Thomas A.; Cuffey, Kurt M.; Buizert, Christo; Taylor, Kendrick C.


    The West Antarctic Ice Sheet Divide Core (WDC) provided a high-resolution climate record from near the Ross-Amundsen Divide in Central West Antarctica. In addition, radar-detected internal layers in the vicinity of the WDC site have been dated directly from the ice core to provide spatial variations in the age structure of the region. Using these two data sets together, we first infer a high-resolution Holocene accumulation-rate history from 9.2 kyr of the ice-core timescale and then confirm that this climate history is consistent with internal layers upstream of the core site. Even though the WDC was drilled only 24 km from the modern ice divide, advection of ice from upstream must be taken into account. We evaluate histories of accumulation rate by using a flowband model to generate internal layers that we compare to observed layers. Results show that the centennially averaged accumulation rate was over 20% lower than modern at 9.2 kyr before present (B.P.), increased by 40% from 9.2 to 2.3 kyr B.P., and decreased by at least 10% over the past 2 kyr B.P. to the modern values; these Holocene accumulation-rate changes in Central West Antarctica are larger than changes inferred from East Antarctic ice-core records. Despite significant changes in accumulation rate, throughout the Holocene the regional accumulation pattern has likely remained similar to today, and the ice-divide position has likely remained on average within 5 km of its modern position. Continent-scale ice-sheet models used for reconstructions of West Antarctic ice volume should incorporate this accumulation history.

  4. An evaluation of the bedrock aquifer system in northeastern Wisconsin (United States)

    Emmons, P.J.


    Ground water is a major source of water in northeastern Wisconsin. The lower Fox River valley, located between Lake Winnebago and Green Bay in northeastern Wisconsin, is the second largest population center in Wisconsin. By 1957, ground-water withdrawals had lowered the potentiometric surface of the aquifer system as much as 440 feet below prepumping levels. With the exception of the city of Green Bay, which converted from ground water to surface water (Lake Michigan) for their municipal water supply in 1957, ground-water withdrawals have continually increased.

  5. Survey of medical radium installations in Wisconsin

    International Nuclear Information System (INIS)

    Tapert, A.C.; Lea, W.L.


    A radiation protection survey was performed at 70 medical radium installations in the State of Wisconsin. The requirements of the State's Radiation Protection Code were used as survey criteria. Radiation measurements of radium storage containers, radium capsule leakage tests, and monitoring of work surfaces for contamination were performed. Film badge monitoring data of whole body and extremity doses are presented for 221 individuals at 17 hospitals. Whole body doses during single treatments ranged from 10 to 1360 mrems per individual. The estimate of 500 mrems per treatment was determined as the dose aggregate to hospital personnel. Whole body doses from film badges are compared with analogous TLD doses. Four physicians and six technicians at nine hospitals participated in a study for monitoring the extremities with TLD. Cumulative extremity doses ranged from 28 to 6628 mrems per participant during the study. (U.S.)

  6. US hydropower resource assessment for Wisconsin

    Energy Technology Data Exchange (ETDEWEB)

    Conner, A.M.; Francfort, J.E.


    The Department of Energy is developing an estimate of the undeveloped hydropower potential in this country. The Hydropower Evaluation Software is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The software measures the undeveloped hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven software program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the State of Wisconsin.

  7. Late Pleistocene eolian features in southeastern Maryland and Chesapeake Bay region indicate strong WNW-NW winds accompanied growth of the Laurentide Ice Sheet (United States)

    Markewich, H.W.; Litwin, R.J.; Pavich, M.J.; Brook, G.A.


    Inactive parabolic dunes are present in southeastern Maryland, USA, along the east bank of the Potomac River. More elongate and finer-grained eolian deposits and paha-like ridges characterize the Potomac River-Patuxent River upland and the west side of Chesapeake Bay. These ridges are streamlined erosional features, veneered with eolian sediment and interspersed with dunes in the low-relief headwaters of Potomac- and Patuxent-river tributaries. Axis data for the dunes and ridges indicate formation by WNW-NW winds. Optically stimulated luminescence and radiocarbon age data suggest dune formation from ??? 33-15??ka, agreeing with the 30-13??ka ages Denny, C.S., Owens, J.P., Sirkin, L., Rubin, M., 1979. The Parsonburg Sand in the central Delmarva Peninsula, Maryland and Delaware. U.S. Geol. Surv. Prof. Pap. 1067-B, 16??pp. suggested for eolian deposits east of Chesapeake Bay. Age range and paleowind direction(s) for eolian features in the Bay region approximate those for late Wisconsin loess in the North American midcontinent. Formation of midcontinent loess and Bay-region eolian features was coeval with rapid growth of the Laurentide Ice Sheet and strong cooling episodes (??18O minima) evident in Greenland ice cores. Age and paleowind-direction coincidence, for eolian features in the midcontinent and Bay region, indicates strong mid-latitude WNW-NW winds for several hundred kilometers south of the Laurentide glacial terminus that were oblique to previously simulated anticyclonic winds for the last glacial maximum.

  8. Perceived Neighborhood Quality and Cancer Screening Behavior: Evidence from the Survey of the Health of Wisconsin. (United States)

    Beyer, Kirsten M M; Malecki, Kristen M; Hoormann, Kelly A; Szabo, Aniko; Nattinger, Ann B


    Socioeconomic disparities in colorectal and breast cancer screening persist, partially accounting for disparities in cancer outcomes. Some neighborhood characteristics--particularly area level socioeconomic factors--have been linked to cancer screening behavior, but few studies have examined the relationship between perceived neighborhood quality and screening behavior, which may provide more insight into the ways in which neighborhood environments shape cancer related behaviors. This study examines the relationship between several aspects of the perceived neighborhood environment and breast and colorectal cancer screening behavior among a population-based sample of Wisconsin residents. A sub-goal was to compare the relevance of different perceived neighborhood factors for different screening tests. This is a cross-sectional study of 2008-2012 data from the Survey of the Health of Wisconsin, a population-based annual survey of Wisconsin residents. An average risk sample of Black, Hispanic and White women age 50 and older (n = 1265) were selected. Survey regression analyses examined predictors of screening, as well as adherence to screening guidelines. Models controlled for individual socio-demographic information and insurance status. Perceptions of social and physical disorder, including fear of crime and visible garbage, were associated with screening rates. Findings emphasize the particular importance of these factors for colorectal cancer screening, indicating the necessity of improving screening rates in areas characterized by social disorganization, crime, and physical disorder. Additional work should be done to further investigate the pathways that explain the linkage between neighborhood conditions, perceived neighborhood risks and cancer screening behavior.

  9. University of Wisconsin Antarctic Soils Database, Version 1 (United States)

    National Aeronautics and Space Administration — The University of Wisconsin Antarctic Soils Database contains data collected by Dr. James G. Bockheim and his colleagues from 1975 through 1987. Data include site...

  10. Forecasting Turbine Icing Events

    DEFF Research Database (Denmark)

    Davis, Neil; Hahmann, Andrea N.; Clausen, Niels-Erik


    In this study, we present a method for forecasting icing events. The method is validated at two European wind farms in with known icing events. The icing model used was developed using current ice accretion methods, and newly developed ablation algorithms. The model is driven by inputs from the WRF...... mesoscale model, allowing for both climatological estimates of icing and short term icing forecasts. The current model was able to detect periods of icing reasonably well at the warmer site. However at the cold climate site, the model was not able to remove ice quickly enough leading to large ice...... accumulations, which have not been seen in observations. In addition to the model evaluation we were able to investigate the potential occurrence of ice induced power loss at two wind parks in Europe using observed data. We found that the potential loss during an icing event is large even when the turbine...

  11. Allan Hills Pleistocene Ice Project (PIP) (United States)

    Kurbatov, A.; Brook, E.; Campbell, S. W.; Conway, H.; Dunbar, N. W.; Higgins, J. A.; Iverson, N. A.; Kehrl, L. M.; McIntosh, W. C.; Spaulding, N. E.; Yan, Y.; Mayewski, P. A.


    A major international effort to identify at least 1.5 Ma old ice for paleoclimate reconstructions has successfully resulted in the selection of several potential drill sites in East Antarctica. At this point it is indisputable that the Antarctic ice sheet captures a continuous envinronmental record of the Earth that spans the Mid Pleistocene Transition (MPT). In addition to traditional ice coring approaches, the oldest ice can also be recovered in Antarctic Blue Ice Areas (BIA). We have already successfully demonstrated that the Allan Hills (AH) BIA captures a regional climate signal and robust record of 1Ma atmosphere that can be studied with a relatively uncomplicated logistical imprint and essentially unlimited sampling volume. The attractiveness of unlimited sampling of known age ice is the basis for the "ice park" concept proposed earlier by our research team. The idea is that, once the age of ice exposed along the flow line at the surface of BIA is mapped, it could be sampled for numerous research projects as needed. Here we propose an intermediate ( 1,150 m deep) ice core drill site, located only 240 km away from McMurdo base that will help to develop a, continuous, high quality regional paleoclimate record that is at least 1Ma old. We will introduce and discuss the glaciological settings, paleoclimate signals and possible limitations and advantages of the 1 Ma AH BIA regional paleoclimate record. The research was funded by NSF Division of Polar Programs.

  12. Pulmonary Blastomycosis in Vilas County, Wisconsin: Weather, Exposures and Symptoms

    Directory of Open Access Journals (Sweden)

    Dennis J. Baumgardner


    Full Text Available Purpose: Blastomycosis is a serious fungal infection contracted by inhalation of Blastomyces spores from the environment. Case occurrence in dogs in Vilas County, Wisconsin, has been associated with antecedent weather. We aimed to explore the effects of weather on the occurrence of human pulmonary blastomycosis in this area, and update exposure factors and symptoms since last published reports. Methods: Mandatory case reports were reviewed. Chi-square test was used for categorical data of exposures, comparing 1979–1996 (n=101 versus 1997–June 2013 (n=95. Linear regression was used to model local weather data (available 1990–2013; n=126; Southern Oscillation Index (SOI, North Atlantic Oscillation Index (NAOI, and Wisconsin River water discharge (WRD from the adjacent county (all available for 1984–2013; n=174; and case counts of known onset by warm (April–September and cold (October–March 6-month periods. Results: Distribution of pulmonary blastomycosis cases did not vary by season. Environmental exposures for the 1997–June 2013 group (mean age 45, 59% male were: residence(76%, excavation (42% and gardening (31%, all similar to the 1979–1996 group. Fishing (23% vs. 37%; P=0.09 and hunting (15% vs. 26%; P=0.13 exposures were less common in 1997–June 2013, but not significantly different. Overall, 69% of cases recalled some prior soil-disturbing activities. Considering the 6-month warm/cold periods, 19% of variation is explained by a direct relationship with total precipitation from two periods prior (P=0.005. There was no association of case occurrence with SOI, NAOI or WRD. Estimated annual incidence of blastomycosis for 1997–June 2013 was 27/100,000 compared with 44/100,000 for 1984–1996. Several symptoms were significantly less frequent in 2002–June 2013 compared to earlier years. Conclusions: As with dogs, human pulmonary blastomycosis occurrence is partially determined by antecedent precipitation. It is unclear if

  13. Ice sheet margins and ice shelves (United States)

    Thomas, R. H.


    The effect of climate warming on the size of ice sheet margins in polar regions is considered. Particular attention is given to the possibility of a rapid response to warming on the order of tens to hundreds of years. It is found that the early response of the polar regions to climate warming would be an increase in the area of summer melt on the ice sheets and ice shelves. For sufficiently large warming (5-10C) the delayed effects would include the breakup of the ice shelves by an increase in ice drainage rates, particularly from the ice sheets. On the basis of published data for periodic changes in the thickness and melting rates of the marine ice sheets and fjord glaciers in Greenland and Antarctica, it is shown that the rate of retreat (or advance) of an ice sheet is primarily determined by: bedrock topography; the basal conditions of the grounded ice sheet; and the ice shelf condition downstream of the grounding line. A program of satellite and ground measurements to monitor the state of ice sheet equilibrium is recommended.

  14. Ice Lithography for Nanodevices

    DEFF Research Database (Denmark)

    Han, Anpan; Kuan, A.; Wang, J.

    Water vapor is condensed onto a cold sample, coating it with a thin-film of ice. The ice is sensitive to electron beam lithography exposure. 10 nm ice patterns are transferred into metals by “melt-off”. Non-planar samples are coated with ice, and we pattern on cantilevers, AFM tips, and suspended...

  15. Community Energy Systems and the Law of Public Utilities. Volume Fifty-one. Wisconsin

    Energy Technology Data Exchange (ETDEWEB)

    Feurer, D.A.; Weaver, C.L.


    A detailed description is presented of the laws and programs of the State of Wisconsin governing the regulation of public energy utilities, the siting of energy generating and transmission facilities, the municipal franchising of public energy utilities, and the prescription of rates to be charged by utilities including attendant problems of cost allocations, rate base and operating expense determinations, and rate of return allowances. These laws and programs are analyzed to identify impediments which they may present to the implementation of Integrated Community Energy Systems (ICES). This report is one of fifty-one separate volumes which describe such regulatory programs at the Federal level and in each state as background to the report entitled Community Energy Systems and the Law of Public Utilities - Volume One: An Overview. This report also contains a summary of a strategy described in Volume One - An Overview for overcoming these impediments by working within the existing regulatory framework and by making changes in the regulatory programs to enhance the likelihood of ICES implementation.

  16. Trends and characteristics of heroin overdoses in Wisconsin, 2003-2012. (United States)

    Meiman, Jon; Tomasallo, Carrie; Paulozzi, Leonard


    Heroin abuse has increased substantially during the past decade in the United States. This study describes trends and demographic shifts of heroin overdoses and heroin-related fatalities in Wisconsin and contrasts these with prescription opioid overdoses. This study was cross-sectional using databases of emergency department (ED) visits, hospital admissions, and death certificates in Wisconsin, United States, during 2003-2012. Cases were Wisconsin residents treated for heroin or prescription opioid overdose, and residents who died of heroin-related drug poisoning. Primary measurements were rates over time and by geographic region, and rates and rate ratios for selected demographic characteristics. During 2003-2012, age-adjusted rates of heroin overdoses treated in EDs increased from 1.0 to 7.9/100,000 persons; hospitalized heroin overdoses increased from 0.7 to 3.5/100,000. Whites accounted for 68% of hospitalized heroin overdoses during 2003-2007 but 80% during 2008-2012. Heroin-related deaths were predominantly among urban residents; however, rural fatalities accounted for zero deaths in 2003 but 31 (17%) deaths in 2012. Among patients aged 18-34 years, those hospitalized with heroin overdose were more often men (73.0% versus 54.9%), uninsured (44.2% versus 29.9%), and urban (84.3% versus 73.2%) than those with prescription opioid overdose. Rates of ED visits for heroin overdose in this age group exceeded rates for prescription opioid overdose in 2012 (26.1/100,000 versus 12.6/100,000 persons, respectively). An epidemic of heroin abuse is characterized by demographic shifts toward whites and rural residents. Rates of heroin overdose in younger persons now exceed rates of prescription opioid overdose. Published by Elsevier Ireland Ltd.

  17. Challenges in validating model results for first year ice (United States)

    Melsom, Arne; Eastwood, Steinar; Xie, Jiping; Aaboe, Signe; Bertino, Laurent


    In order to assess the quality of model results for the distribution of first year ice, a comparison with a product based on observations from satellite-borne instruments has been performed. Such a comparison is not straightforward due to the contrasting algorithms that are used in the model product and the remote sensing product. The implementation of the validation is discussed in light of the differences between this set of products, and validation results are presented. The model product is the daily updated 10-day forecast from the Arctic Monitoring and Forecasting Centre in CMEMS. The forecasts are produced with the assimilative ocean prediction system TOPAZ. Presently, observations of sea ice concentration and sea ice drift are introduced in the assimilation step, but data for sea ice thickness and ice age (or roughness) are not included. The model computes the age of the ice by recording and updating the time passed after ice formation as sea ice grows and deteriorates as it is advected inside the model domain. Ice that is younger than 365 days is classified as first year ice. The fraction of first-year ice is recorded as a tracer in each grid cell. The Ocean and Sea Ice Thematic Assembly Centre in CMEMS redistributes a daily product from the EUMETSAT OSI SAF of gridded sea ice conditions which include "ice type", a representation of the separation of regions between those infested by first year ice, and those infested by multi-year ice. The ice type is parameterized based on data for the gradient ratio GR(19,37) from SSMIS observations, and from the ASCAT backscatter parameter. This product also includes information on ambiguity in the processing of the remote sensing data, and the product's confidence level, which have a strong seasonal dependency.

  18. Stochastic ice stream dynamics. (United States)

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca


    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution.

  19. Sea Ice Ecosystems (United States)

    Arrigo, Kevin R.


    Polar sea ice is one of the largest ecosystems on Earth. The liquid brine fraction of the ice matrix is home to a diverse array of organisms, ranging from tiny archaea to larger fish and invertebrates. These organisms can tolerate high brine salinity and low temperature but do best when conditions are milder. Thriving ice algal communities, generally dominated by diatoms, live at the ice/water interface and in recently flooded surface and interior layers, especially during spring, when temperatures begin to rise. Although protists dominate the sea ice biomass, heterotrophic bacteria are also abundant. The sea ice ecosystem provides food for a host of animals, with crustaceans being the most conspicuous. Uneaten organic matter from the ice sinks through the water column and feeds benthic ecosystems. As sea ice extent declines, ice algae likely contribute a shrinking fraction of the total amount of organic matter produced in polar waters.

  20. Ross Ice Shelf, Antarctic Ice and Clouds (United States)


    In this view of Antarctic ice and clouds, (56.5S, 152.0W), the Ross Ice Shelf of Antarctica is almost totally clear, showing stress cracks in the ice surface caused by wind and tidal drift. Clouds on the eastern edge of the picture are associated with an Antarctic cyclone. Winds stirred up these storms have been known to reach hurricane force.

  1. Wisconsin Healthy Birth Outcomes: minority health program challenges and contributions. (United States)

    Cruz, Evelyn; Guhleman, Patricia; Onheiber, Patrice Mocny


    For at least 20 years, the probability that an infant born in Wisconsin would die during the first year of life has been approximately three times greater for infants born to African American women than for those born to White women. Over the same period of time, other states have made improvements in African American infant mortality, whereas Wisconsin's ranking has fallen to last place. Various state and local efforts have been made to address the issue; however, it is only in the last 2 to 3 years that Wisconsin's high rate of African American infant mortality has become an agreed-upon health priority. This article discusses the factors that have converged to bring African American infant mortality to the forefront of Wisconsin public health policy and programs. Particular attention is given to the role of Wisconsin's Minority Health Program in relation to public health leadership and coalition building. Key actions currently underway to implement effective, evidence-based solutions are also described.

  2. Muskellunge growth potential in northern Wisconsin: implications for trophy management (United States)

    Faust, Matthew D.; Isermann, Daniel A.; Luehring, Mark A.; Hansen, Michael J.


    The growth potential of Muskellunge Esox masquinongy was evaluated by back-calculating growth histories from cleithra removed from 305 fish collected during 1995–2011 to determine whether it was consistent with trophy management goals in northern Wisconsin. Female Muskellunge had a larger mean asymptotic length (49.8 in) than did males (43.4 in). Minimum ultimate size of female Muskellunge (45.0 in) equaled the 45.0-in minimum length limit, but was less than the 50.0-in minimum length limit used on Wisconsin's trophy waters, while the minimum ultimate size of male Muskellunge (34.0 in) was less than the statewide minimum length limit. Minimum reproductive sizes for both sexes were less than Wisconsin's trophy minimum length limits. Mean growth potential of female Muskellunge in northern Wisconsin appears to be sufficient for meeting trophy management objectives and angler expectations. Muskellunge in northern Wisconsin had similar growth potential to those in Ontario populations, but lower growth potential than Minnesota's populations, perhaps because of genetic and environmental differences.

  3. Aging

    International Nuclear Information System (INIS)

    Sasaki, Hideo; Kodama, Kazunori; Yamada, Michiko


    The hypothesis that exposure to ionizing radiation accelerates the aging process has been actively investigated at ABCC-RERF since 1958, when longitudinal cohort studies of the Adult Health Study (AHS) and the Life Span Study (LSS) were initiated. In their 1975 overall review of aging studies related to the atomic bomb (A-bomb) survivors, Finch and Beebe concluded that while most studies had shown no correlation between aging and radiation exposure, they had not involved the large numbers of subjects required to provide strong evidence for or against the hypothesis. Extending LSS mortality data up to 1978 did not alter the earlier conclusion that any observed life-shortening was associated primarily with cancer induction rather than with any nonspecific cause. The results of aging studies conducted during the intervening 15 years using data from the same populations are reviewed in the present paper. Using clinical, epidemiological, and laboratory techniques, a broad spectrum of aging parameters have been studied, such as postmortem morphological changes, tests of functional capacity, physical tests and measurements, laboratory tests, tissue changes, and morbidity. With respect to the aging process, the overall results have not been consistent and are generally thought to show no relation to radiation exposure. Although some preliminary results suggest a possible radiation-induced increase in atherosclerotic diseases and acceleration of aging in the T-cell-related immune system, further study is necessary to confirm these findings. In the future, applying the latest gerontological study techniques to data collected from subjects exposed 45 years ago to A-bomb radiation at relatively young ages will present a new body of data relevant to the study of late radiation effects. (author) 103 refs

  4. Inception of the Laurentide Ice Sheet using asynchronous coupling of a regional atmospheric model and an ice model (United States)

    Birch, L.; Cronin, T.; Tziperman, E.


    The climate over the past 0.8 million years has been dominated by ice ages. Ice sheets have grown about every 100 kyrs, starting from warm interglacials, until they spanned continents. State-of-the-art global climate models (GCMs) have difficulty simulating glacial inception, or the transition of Earth's climate from an interglacial to a glacial state. It has been suggested that this failure may be related to their poorly resolved local mountain topography, due to their coarse spatial resolution. We examine this idea as well as the possible role of ice flow dynamics missing in GCMs. We investigate the growth of the Laurentide Ice Sheet at 115 kya by focusing on the mountain glaciers of Canada's Baffin Island, where geologic evidence indicates the last inception occurred. We use the Weather Research and Forecasting model (WRF) in a regional, cloud-resolving configuration with resolved mountain terrain to explore how quickly Baffin Island could become glaciated with the favorable yet realizable conditions of 115 kya insolation, cool summers, and wet winters. Using the model-derived mountain glacier mass balance, we force an ice sheet model based on the shallow-ice approximation, capturing the ice flow that may be critical to the spread of ice sheets away from mountain ice caps. The ice sheet model calculates the surface area newly covered by ice and the change in the ice surface elevation, which we then use to run WRF again. Through this type of iterated asynchronous coupling, we investigate how the regional climate responds to both larger areas of ice cover and changes in ice surface elevation. In addition, we use the NOAH-MP Land model to characterize the importance of land processes, like refreezing. We find that initial ice growth on the Penny Ice Cap causes regional cooling that increases the accumulation on the Barnes Ice Cap. We investigate how ice and topography changes on Baffin Island may impact both the regional climate and the large-scale circulation.

  5. Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for Wisconsin

    Energy Technology Data Exchange (ETDEWEB)

    Mendon, Vrushali V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhao, Mingjie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Taylor, Zachary T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Poehlman, Eric A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    The 2015 IECC provides cost-effective savings for residential buildings in Wisconsin. Moving to the 2015 IECC from the 2006 IECC base code is cost-effective for residential buildings in all climate zones in Wisconsin.

  6. Hydrology of upper Black Earth Creek basin, Wisconsin (United States)

    Cline, Denzel R.; Busby, Mark W.


    The upper Black Earth Creek drainage basin has an area of 46 square miles and is in Dane County in south-central Wisconsin. The oldest rock exposed in the valley walls is the sandstone of Late Cambrian age. Dolomite of the Prairie du Chien Group of Ordovician age overlies the sandstone and forms the. resistant cap on the hills. The St. Peter Sandstone, Platteville and Decorah Formations, and Galena Dolomite, all Ordovician in age, form a narrow belt along the southern boundary of the area. Outwash and alluvium of Pleistocene and Recent age fill the valleys. The eastern half of the area was glaciated and is covered with till. The sandstone of Late Cambrian age and the sand and gravel of the outwash deposits are hydraulically connected. Ground water occurs under unconfined (water-table) conditions in the western unglaciated part of the basin and under artesian conditions beneath the till locally in the eastern part. The source of most of the ground water is direct infiltration of precipitation; however, some ground water enters the area as underflow from the south. About 7 inches of the 30 inches of average annual precipitation recharges the ground-water reservoir. The ground water generally moves toward Black Earth Creek where it is discharged. Some ground water moves out of the basin as underflow beneath the valley of Black Earth Creek, and some is discharged by evapotranspiration or is withdrawn by pumping from wells. Water levels in shallow nonartesian wells respond rapidly to precipitation. The effect of precipitation on water levels in artesian wells is slower and more subdued. Water levels are generally highest in spring and lowest in fall and winter. The flow of upper Black Earth Creek is derived mostly from ground-water discharge, except during short periods of and immediately after precipitation when most of the flow is derived from surface runoff. The runoff from upper Black Earth Creek basin decreased from an average of 8.72 inches per square mile of

  7. Gas records from the West Greenland ice margin covering the Last Glacial termination: a horizontal ice core

    DEFF Research Database (Denmark)

    Petrenko, V.; Severinghaus, J.P.; Brook, E.J.


    and Preboreal intervals. Extensive sections of ice from the Holocene and most ages within the last glacial period are probably also present. Very accurate dating has been possible in the ice section containing the Younger Dryas-Preboreal abrupt climate transition signal. The ice at Pakitsoq is folded and non......Certain sites along ice sheet margins provide an easily accessible and almost unlimited supply of ancient ice at the surface. Measurements of gases in trapped air from ice outcropping at Pakitsoq, West Greenland, demonstrate that ancient air is mostly well preserved. No alterations in delta O-18......(atm) and delta N-15 of N-2 are apparent, and alterations in methane are found in only a few ice sections. Using measurements of these gases, we have unambiguously identified a stratigraphic section containing ice from the end of last glacial period as well as Bolling-Allerod, Younger Dryas...

  8. Capabilities and performance of Elmer/Ice, a new-generation ice sheet model

    Directory of Open Access Journals (Sweden)

    O. Gagliardini


    Full Text Available The Fourth IPCC Assessment Report concluded that ice sheet flow models, in their current state, were unable to provide accurate forecast for the increase of polar ice sheet discharge and the associated contribution to sea level rise. Since then, the glaciological community has undertaken a huge effort to develop and improve a new generation of ice flow models, and as a result a significant number of new ice sheet models have emerged. Among them is the parallel finite-element model Elmer/Ice, based on the open-source multi-physics code Elmer. It was one of the first full-Stokes models used to make projections for the evolution of the whole Greenland ice sheet for the coming two centuries. Originally developed to solve local ice flow problems of high mechanical and physical complexity, Elmer/Ice has today reached the maturity to solve larger-scale problems, earning the status of an ice sheet model. Here, we summarise almost 10 yr of development performed by different groups. Elmer/Ice solves the full-Stokes equations, for isotropic but also anisotropic ice rheology, resolves the grounding line dynamics as a contact problem, and contains various basal friction laws. Derived fields, like the age of the ice, the strain rate or stress, can also be computed. Elmer/Ice includes two recently proposed inverse methods to infer badly known parameters. Elmer is a highly parallelised code thanks to recent developments and the implementation of a block preconditioned solver for the Stokes system. In this paper, all these components are presented in detail, as well as the numerical performance of the Stokes solver and developments planned for the future.

  9. Antarctic Ice Velocity Data (United States)

    National Aeronautics and Space Administration — This compilation of recent ice velocity data of the Antarctic ice sheet is intended for use by the polar scientific community. The data are presented in tabular form...

  10. Current Icing Product (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Current Icing Product (CIP) is an automatically-generated index suitable for depicting areas of potentially hazardous airframe icing. The CIP algorithm combines...

  11. Of Needles and Haystacks: Building an Accurate Statewide Dropout Early Warning System in Wisconsin (United States)

    Knowles, Jared E.


    The state of Wisconsin has one of the highest four year graduation rates in the nation, but deep disparities among student subgroups remain. To address this the state has created the Wisconsin Dropout Early Warning System (DEWS), a predictive model of student dropout risk for students in grades six through nine. The Wisconsin DEWS is in use…

  12. 77 FR 71587 - Wisconsin Public Service Corporation; Notices of Intent To File License Applications, Filing of... (United States)


    ... Energy Regulatory Commission Wisconsin Public Service Corporation; Notices of Intent To File License.... d. Submitted By: Wisconsin Public Service Corporation. e. Name of Projects: Tomahawk Hydroelectric..., Vice President, Energy Supply Operations, Wisconsin Public Service Corporation, P.O. Box 19001, 700...

  13. 76 FR 48841 - Wisconsin Public Service Corporation; Notice of Application for Amendment of License and... (United States)


    ... Energy Regulatory Commission Wisconsin Public Service Corporation; Notice of Application for Amendment of..., 2011. d. Applicant: Wisconsin Public Service Corporation. e. Name of Project: High Falls Project. f.... 791a-825r. h. Applicant Contact: James Nuthals, Wisconsin Public Service Corporation, 700 North Adams...

  14. Introduction to radioactive waste management issues in Wisconsin

    International Nuclear Information System (INIS)



    This brief focused on wastes from commercial production of electricity and various industrial, medical and research applications of radioactive materials. Only traditionally solid wastes are dealt with. It was organized into five parts. Part I presented an introduction to radioactivity - what it is and the biological hazards associated with it. Federal regulation of the management of radioactive wastes was discussed in Part II. Existing state laws and bills currently before the Wisconsin Legislature were described in Part III. Part IV gave background information on specific areas of potential inquiry related to radioactive wastes in Wisconsin. Part V summarized the issues identified in the brief. 2 figures, 7 tables

  15. Biblioteca y Centro de Estudios de la Universidad de Wisconsin - Kenosha - . Wisconsin – (EE.UU.

    Directory of Open Access Journals (Sweden)

    Hellmuth, George


    Full Text Available Continuing the line established by these same architects in previous University designs, the Library and Study Hall of the University of Wisconsin is another attempt at creating an exciting atmosphere, particularly conducive to the development of university life. It is to be noted, in this case, the arrangement of the library and study areas around a central common open space, sort of an inner courtyard used as a relaxation and sitting área, where all traffic corridors and promenades from the adjacent faculties come to meet, thus becoming the main reference point for the entire campus. The library with a current capacity for 245,000 volumes and 1,400 reading stalls is designed so it can be eventually enlarged permitting to almost double its book capacity and increasing the reading stalls to more than 2,000.

    Continuando la línea marcada por estos mismos arquitectos en anteriores proyectos de universidades, la biblioteca y el centro de estudios de la Universidad de Wisconsin procura definir atractivos espacios para el desarrollo de la vida universitaria. En este caso destaca la organización de los servicios de biblioteca y estudio en torno a un espacio comunitario central, a modo de plaza interior, destinado a sala de estar y recreo, y en donde confluyen las circulaciones que provienen de los locales adyacentes, convirtiéndolo en el principal punto de referencia del campus universitario. La biblioteca, que actualmente tiene capacidad para 245.000 volúmenes y 1.400 lectores, ha previsto una ampliación que le permitirá casi doblar el número de volúmenes y proporcionar espacio para más de 2.000 lectores.

  16. Aircraft Icing Handbook. (Update) (United States)


    pp. 68-69, 1947. Speranza, F., OThe Formation of Ice,a Rivista di Meteorologia Aeronautics, 1(2), pp. 19-30, 1937. Steiner, R. 0., "The Icing of...Deposits of Ice on Airplane Carburetors,8 (Translation) Rivista di Meteorologia Aeronautica, 4(2), pp. 38-47, 1940. Von Glahn, U. H.; Renner, C. E

  17. Technology for Ice Rinks (United States)


    Ron Urban's International Ice Shows set up portable ice rinks for touring troupes performing on temporary rinks at amusement parks, sports arenas, dinner theaters, shopping malls and civic centers. Key to enhanced rink portability, fast freezing and maintaining ice consistency is a mat of flexible tubing called ICEMAT, an offshoot of a solar heating system developed by Calmac, Mfg. under contract with Marshall.

  18. Glacial Lake Lind, Wisconsin and Minnesota (United States)

    Johnson, M.D.; Addis, K.L.; Ferber, L.R.; Hemstad, C.B.; Meyer, G.N.; Komai, L.T.


    Glacial Lake Lind developed in the pre-late Wisconsinan St. Croix River valley, Minnesota and Wisconsin, and lasted more than 1000 yr during the retreat of the Superior lobe at the end of the Wisconsinan glaciation. Lake Lind sediment consists primarily of red varved silt and clay, but also includes mud-flow deposits, nearshore silt (penecontemporaneously deformed in places), nearshore rippled sand, and deltaic sand. Lake Lind varved red clay is not part of glacial Lake Grantsburg, as suggested by earlier authors, because the red varves are separated from overlying glacial Lake Grantsburg silt and clay by a unit of deltaic and fluvial sand. Furthermore, varve correlations indicate that the base of the red varves is younger to the north, showing that the basin expanded as the Superior lobe retreated and was not a lake basin dammed to the southwest by the advancing Grantsburg sublobe. Varve correlations indicate that the Superior lobe retreated at a rate of about 200 m/yr. Uniform winter-clay thickness throughout most of the varve couplets suggests thermal stratification in the lake with clay trapped in the epilimnion; some clay would exit the lake at the outlet prior to winter freeze. Zones of thicker winter-clay layers, in places associated with mud-flow layers, indicate outlet incision, lake-level fall, and shoreline erosion and resuspension of lake clay. The most likely outlet for glacial Lake Lind was in the southwest part of the lake near the present site of Minneapolis, Minnesota. Nearshore sediment indicates that the lake level of glacial Lake Lind was around 280 m. The elevation of the base of the Lake Lind sediments indicates water depth was 20 to 55 m. Evidence in the southern part of the lake basin suggests that the Superior lobe readvanced at least once during the early stages of glacial Lake Lind. Lake Lind ended not by drainage but by being filled in by prograding deltas and outwash plains composed of sand derived from the retreating Superior lobe. It

  19. Increasing educational disparities in premature adult mortality, Wisconsin, 1990-2000. (United States)

    Reither, Eric N; Peppard, Paul E; Remington, Patrick L; Kindig, David A


    Public health agencies have identified the elimination of health disparities as a major policy objective. The primary objective of this study is to assess changes in the association between education and premature adult mortality in Wisconsin, 1990-2000. Wisconsin death records (numerators) and US Census data (denominators) were compiled to estimate mortality rates among adults (25-64 years) in 1990 and 2000. Information on the educational status, sex, racial identification, and age of subjects was gathered from these sources. The effect of education on mortality rate ratios in 1990 and 2000 was assessed while adjusting for age, sex, and racial identification. Education exhibited a graded effect on mortality rates, which declined most among college graduates from 1990 to 2000. The relative rate of mortality among persons with less than a high school education compared to persons with a college degree increased from 2.4 to 3.1 from 1990-2000-an increase of 29%. Mortality disparities also increased, although to a lesser extent, among other educational groups. Despite renewed calls for the elimination of health disparities, evidence suggests that educational disparities in mortality increased from 1990 to 2000.

  20. The Influence of Ice Properties on Borehole Deformation at the West Antarctic Ice Sheet Divide (United States)

    Sinkler, E.; Pettit, E. C.; Obbard, R. W.


    It is widely known that ice flow is affected by many properties, including crystal fabric and impurities, though these relationships are not fully understood. This study uses data from the West Antarctic Ice Sheet (WAIS) Divide borehole to better determine the influence of such properties on ice flow. The WAIS Divide borehole, the byproduct of the 2006-2012 coring project, offers a unique opportunity to study deep Antarctic Ice. Thanks to the work of many researchers, extensive data on ice properties are available from both coring and borehole logging at this site. The borehole, kept open with a density-approximating fluid, closes and tilts due to ice flow. We have tracked this deformation over two years using a set of repeat measurements with an Acoustic Televiewer. This tool acts as an acoustic caliper allowing us to view cross-sections of the borehole shape and size with up to 1.25 degree azimuthal resolution and a depth resolution as high as 1.4 mm. In addition, the tool collects tilt and azimuth data. These measurements are compared to a 1D Glen's Flow Law model for borehole closure that uses density differences between the ice and borehole fluid as its driving force and incorporates temperature effects. This is then compared to ice properties like crystal fabric and impurities in order to determine the influence of these properties on ice deformation at this site. Crystal fabric has appeared as an important factor in this study.This work builds on that of others who have studied in-situ deep ice through borehole deformation (e.g. Paterson, 1977 and Dahl-Jensen and Gundestrup, 1987). Our results have implications for ice flow modeling and therefore interpretation of depth-age relationships in deep ice cores.

  1. Arctic ice management (United States)

    Desch, Steven J.; Smith, Nathan; Groppi, Christopher; Vargas, Perry; Jackson, Rebecca; Kalyaan, Anusha; Nguyen, Peter; Probst, Luke; Rubin, Mark E.; Singleton, Heather; Spacek, Alexander; Truitt, Amanda; Zaw, Pye Pye; Hartnett, Hilairy E.


    As the Earth's climate has changed, Arctic sea ice extent has decreased drastically. It is likely that the late-summer Arctic will be ice-free as soon as the 2030s. This loss of sea ice represents one of the most severe positive feedbacks in the climate system, as sunlight that would otherwise be reflected by sea ice is absorbed by open ocean. It is unlikely that CO2 levels and mean temperatures can be decreased in time to prevent this loss, so restoring sea ice artificially is an imperative. Here we investigate a means for enhancing Arctic sea ice production by using wind power during the Arctic winter to pump water to the surface, where it will freeze more rapidly. We show that where appropriate devices are employed, it is possible to increase ice thickness above natural levels, by about 1 m over the course of the winter. We examine the effects this has in the Arctic climate, concluding that deployment over 10% of the Arctic, especially where ice survival is marginal, could more than reverse current trends of ice loss in the Arctic, using existing industrial capacity. We propose that winter ice thickening by wind-powered pumps be considered and assessed as part of a multipronged strategy for restoring sea ice and arresting the strongest feedbacks in the climate system.

  2. Dead-ice environments

    DEFF Research Database (Denmark)

    Krüger, Johannes; Kjær, Kurt H.; Schomacker, Anders


    Kötlujökull transports considerable amounts of supraglacial debris at its snout because of frontal oscillations with frequent ice advances followed by ice-margin stagnation. Kötlujökull provides suitable conditions of studying dead-ice melting and landscape formation in a debris-charged lowland...... glacier environment. The scientific challenges are to answer the key questions. What are the conditions for dead-ice formation? From which sources does the sediment cover originate? Which melting and reworking processes act in the ice-cored moraines? What is the rate of de-icing in the ice-cored moraines...... under humid, sub-polar conditions? Does this rate differ from rates reported from polar environments of dry continental nature? How will the sedimentary architecture appear in the geological record? How will the final landsystem appear? These key questions are answered in a review of research...

  3. Historical Trends, Drivers, and Future Projections of Ice Phenology in Small North Temperate Lakes in the Laurentian Great Lakes Region

    Directory of Open Access Journals (Sweden)

    Bailey A. Hewitt


    Full Text Available Lake ice phenology (timing of ice breakup and freeze up is a sensitive indicator of climate. We acquired time series of lake ice breakup and freeze up, local weather conditions, and large-scale climate oscillations from 1981–2015 for seven lakes in northern Wisconsin, USA, and two lakes in Ontario, Canada. Multiple linear regression models were developed to understand the drivers of lake ice phenology. We used projected air temperature and precipitation from 126 climate change scenarios to forecast the day of year of ice breakup and freeze up in 2050 and 2070. Lake ice melted 5 days earlier and froze 8 days later over the past 35 years. Warmer spring and winter air temperatures contributed to earlier ice breakup; whereas warmer November temperatures delayed lake freeze. Lake ice breakup is projected to be 13 days earlier on average by 2070, but could vary by 3 days later to 43 days earlier depending upon the degree of climatic warming by late century. Similarly, the timing of lake freeze up is projected to be delayed by 11 days on average by 2070, but could be 1 to 28 days later. Shortened seasonality of ice cover by 24 days could increase risk of algal blooms, reduce habitat for coldwater fisheries, and jeopardize survival of northern communities reliant on ice roads.

  4. Digital Learning Compass: Distance Education State Almanac 2017. Wisconsin (United States)

    Seaman, Julia E.; Seaman, Jeff


    This brief report uses data collected under the U.S. Department of Education's National Center for Educational Statistics (NCES) Integrated Postsecondary Education Data System (IPEDS) Fall Enrollment survey to highlight distance education data in the state of Wisconsin. The sample for this analysis is comprised of all active, degree-granting…

  5. Dragonflies are biocontrol agents in Wisconsin cranberry marshes (United States)

    Dragonflies (Order Odonata) are abundant predators that emerge in large hatch events each summer in Wisconsin cranberry marshes. They seem to be a potential group of biocontrol agents for pest management that may be influenced by the diversity found on the marsh. In fact, our evidence shows that dra...

  6. Southeastern Wisconsin Workplace Communication Project Curriculum Development Guide. (United States)

    Frederick, Catherine; Huss-Lederman, Susan; Johnson, Jewelie

    The Southeastern Wisconsin Workplace Communication Project is a workplace English-as-a-Second-Language (ESL) resource and outreach program involving a partnership of businesses and adult educators in a rural area that has experienced an increase in new speakers of English in the manufacturing workforce. The guide provides workplace educators and…


    Spatial synchrony in population dynamics is a topic of increasing interest in basic and applied ecology. We used data from 18 years of frog and toad calling surveys conducted throughout Wisconsin to determine the level of intraspecific synchrony among survey sites, and the relat...

  8. On Farmers’ Ground: Wisconsin Dairy Farm Nutrient Management Survey Questionnaire (United States)

    This questionnaire was used during quarterly, face-to-face interviews with the fifty-four Wisconsin dairy farmers who participated in the ‘On Farmers’ Ground’ nutrient management research project. It was designed to systematically and consistently compile information on herd size and composition, l...

  9. Quaternary Glacial Mapping in Western Wisconsin Using Soil Survey Information (United States)

    Oehlke, Betsy M.; Dolliver, Holly A. S.


    The majority of soils in the western Wisconsin have developed from glacial sediments deposited during the Quaternary Period (2.6 million years before present). In many regions, multiple advances and retreats have left a complex landscape of diverse glacial sediments and landforms. The soils that have developed on these deposits reflect the nature…

  10. The Wisconsin experience with incentives for demand-side management

    International Nuclear Information System (INIS)

    Landgren, D.A.


    It has been noted that, within traditional regulatory frameworks for electric utilities, factors exist which discourage demand side management (DSM) and that there is a lack of positive incentives for DSM. Regulatory agencies should therefore make it possible for DSM measures to benefit from the same treatment as supply-side measures. The Wisconsin Public Service Commission (WPSC) has recognized this need and has adopted various measures accordingly. The need for efficiency incentives is described according to the particular experience of Wisconsin Electric concerning their recourse to a DSM incentive and according to new incentive models being tested in collaboration with other electricity suppliers in Wisconsin. The WPSC has concluded that the fact of considering the costs relating to DSM as expenses or capitalizing them within the rate base does not motivate the utility to promote DSM programs. The WPSC has thus decided to experiment with energy efficiency incentives in order to evaluate their eventual impact. The choice of the type of incentive had an objective of starting the process in an area where the lack of experience has created, from the regulatory point of view, a reticence on the part of utilities to engage in DSM programs. The WPSC has designed a variety of incentive models which have been adapted to each utility's own situation. Specific incentive programs developed for three Wisconsin utilities are reviewed

  11. Wisconsin's Infants and Toddlers. Publication #2015-17 (United States)

    Murphey, David; Cooper, Mae


    Wisconsin's infants and toddlers (defined as children less than three years old) are more than 200,000 in number. Seventy-one percent are white/non-Hispanic, and the largest minority group is Hispanic, at 12 percent. Black, Asian American, and American Indian infants and toddlers make up smaller percentages. To help states target policies related…

  12. 77 FR 16674 - Establishment of the Wisconsin Ledge Viticultural Area (United States)


    .... All of the comments expressed support for the proposed Wisconsin Ledge viticultural area. TTB... label reference on a wine that indicates or implies an origin other than the wine's true place of origin... or other term identified as being viticulturally significant in part 9 of the TTB regulations, at...

  13. Skill Needs and Training Strategies in the Wisconsin Printing Industry. (United States)

    Wisconsin Univ., Madison. Center on Wisconsin Strategy.

    A study examined the emerging skill needs in the Wisconsin printing industry, a key industry that provided the largest increase (more than 13,000 new jobs) in manufacturing employment in the state in the past decade. Eighteen interviews were conducted with industry personnel and production managers, union representatives, technical college…

  14. Autonomous Aerial Ice Observation for Ice Defense

    Directory of Open Access Journals (Sweden)

    Joakim Haugen


    Full Text Available One of the tasks in ice defense is to gather information about the surrounding ice environment using various sensor platforms. In this manuscript we identify two monitoring tasks known in literature, namely dynamic coverage and target tracking, and motivate how these tasks are relevant in ice defense using RPAS. An optimization-based path planning concept is outlined for solving these tasks. A path planner for the target tracking problem is elaborated in more detail and a hybrid experiment, which consists of both a real fixed-wing aircraft and simulated objects, is included to show the applicability of the proposed framework.

  15. Automatic Weather Station (AWS Program operated by the University of Wisconsin-Madison during the 2011-2012 field season

    Directory of Open Access Journals (Sweden)

    Matthew A. Lazzara


    Full Text Available During the 2011-2012 austral summer, the Antarctic Automatic Weather Station (AWS program at the University of Wisconsin?Madison completed its 32nd year of observations. Ongoing studies utilizing the network include topics in Antarctic meteorology and climate studies. This field season consisted of work throughout the Ross Island area, the Ross Ice Shelf, West Antarctica, and East Antarctica. Argos satellite transmissions are the primary method for relaying station data, but throughout this year, a number of stations in the Ross Island area have been converted to Freewave modems, with their data being relayed through McMurdo station. Each AWS station report contains information regarding the instrumentation currently installed and the work performed at each site. An overview of the AWS applications is included along with field work accomplished.

  16. The Paleozoic Dust Bowl: Dust Deposition in Tropical Western Pangaea (Midcontinent U.S.) at the Terminus of the Late Paleozoic Ice Age (United States)

    Soreghan, G. S.; Heavens, N. G.; Benison, K. C.; Soreghan, M. J.; Mahowald, N. M.; Foster, T.; Zambito, J.; Sweet, A.; Kane, M.


    Atmospheric dust is well recognized and studied as both an archive and agent of climate change in Earth's relatively recent past. Archives of past dust include loess deposits and dust recovered from ocean- and ice-cores. Dust remains poorly known in Earth's past prior to the Cenozoic, but is increasingly recognized in the form of paleo-loess deposits, and (epeiric) marine strata that accumulated isolated from fluvio-deltaic influx. Here, we report on the growing recognition of voluminous dust deposits preserved in the Permian record of the U.S. Midcontinent (western tropical Pangaea). Fine-grained redbeds predominate in Permian strata throughout the U.S. Midcontinent, but notably in a swath extending from Oklahoma through South Dakota. These units consist predominantly of red mudstone and siltstone in commonly massive units, but sedimentary structures and bedding that signal aqueous processes (e.g. laminations, ripples) have led most to infer deltaic or tidal deposition. The absence of channel systems to deliver the sediment, as well as the predominantly massive and laterally continuous character and the uniform fine grain size signal wind transport, implying that these units record sustained dust deposition overprinted at times by sub-aqueous deposition in lakes, including ephemeral saline and acid lakes that led to evaporite cementation. Detrital zircon geochronology indicates that much of the dust originated in the relatively distant Appalachian-Ouachita orogenic systems, which formed part of the central Pangaean mountains (CPM), the collisional zone that sutured the supercontinent. Within the Anadarko basin of Oklahoma, Permian redbeds record >2 km of predominantly dust deposition, some of the thickest dust deposits yet documented in Earth's record. Yet the tropical setting is remarkably non-uniformitarian, as much Quaternary loess occurs in mid- to high-latitude regions, commonly linked to glacial genesis. We are currently investigating with both data and

  17. connecting the dots between Greenland ice sheet surface melting and ice flow dynamics (Invited) (United States)

    Box, J. E.; Colgan, W. T.; Fettweis, X.; Phillips, T. P.; Stober, M.


    This presentation is of a 'unified theory' in glaciology that first identifies surface albedo as a key factor explaining total ice sheet mass balance and then surveys a mechanistic self-reinforcing interaction between melt water and ice flow dynamics. The theory is applied in a near-real time total Greenland mass balance retrieval based on surface albedo, a powerful integrator of the competing effects of accumulation and ablation. New snowfall reduces sunlight absorption and increases meltwater retention. Melting amplifies absorbed sunlight through thermal metamorphism and bare ice expansion in space and time. By ';following the melt'; we reveal mechanisms linking existing science into a unified theory. Increasing meltwater softens the ice sheet in three ways: 1.) sensible heating given the water temperature exceeds that of the ice sheet interior; 2.) Some infiltrating water refreezes, transferring latent heat to the ice; 3.) Friction from water turbulence heats the ice. It has been shown that for a point on the ice sheet, basal lubrication increases ice flow speed to a time when an efficient sub-glacial drainage network develops that reduces this effect. Yet, with an increasing melt duration the point where the ice sheet glides on a wet bed increases inland to a larger area. This effect draws down the ice surface elevation, contributing to the ';elevation feedback'. In a perpetual warming scenario, the elevation feedback ultimately leads to ice sheet loss reversible only through much slower ice sheet growth in an ice age environment. As the inland ice sheet accelerates, the horizontal extension pulls cracks and crevasses open, trapping more sunlight, amplifying the effect of melt accelerated ice. As the bare ice area increases, the direct sun-exposed crevassed and infiltration area increases further allowing the ice warming process to occur more broadly. Considering hydrofracture [a.k.a. hydrofracking]; surface meltwater fills cracks, attacking the ice integrity

  18. Reconstructing the temperature regime of the Weichselian ice sheet

    International Nuclear Information System (INIS)

    Holmlund, P.


    Areas in Sweden are described, where the ice could have been at the pressure melting point during the last ice age. In order to calculate probable degrees of glacial erosion, estimates on the time of ice coverage and the temperature distribution in time are combined data on erosion rates from present day glaciers. An estimate of the extent of ice cover can be made using the proxy temperature record from the Greenland ice cores and a model of the ice sheet. Adding the estimations on climate and ice sheet shape outlined in this contribution, to erosion figures we may conclude that the crucial areas for glaciation erosion are within the mountains and where the present Baltic and the Gulf of Bothnia are situated. At these sites erosion rates of some tens of meters may have occurred. In inland northern Sweden and inland southern Sweden the potential for glacial erosion seems to be small. 14 refs

  19. Reconstructing the temperature regime of the Weichselian ice sheet

    Energy Technology Data Exchange (ETDEWEB)

    Holmlund, P. [Stockholm Univ. (Sweden). Dept. of Physical Geography


    Areas in Sweden are described, where the ice could have been at the pressure melting point during the last ice age. In order to calculate probable degrees of glacial erosion, estimates on the time of ice coverage and the temperature distribution in time are combined data on erosion rates from present day glaciers. An estimate of the extent of ice cover can be made using the proxy temperature record from the Greenland ice cores and a model of the ice sheet. Adding the estimations on climate and ice sheet shape outlined in this contribution, to erosion figures we may conclude that the crucial areas for glaciation erosion are within the mountains and where the present Baltic and the Gulf of Bothnia are situated. At these sites erosion rates of some tens of meters may have occurred. In inland northern Sweden and inland southern Sweden the potential for glacial erosion seems to be small. 14 refs.

  20. Land Ice: Greenland & Antarctic ice mass anomaly (United States)

    National Aeronautics and Space Administration — Data from NASA's Grace satellites show that the land ice sheets in both Antarctica and Greenland are losing mass. The continent of Antarctica (left chart) has been...

  1. Periodical Publishing in Wisconsin. Proceedings of the Conference on Periodical Publishing in Wisconsin (Madison, WI, May 11-12, 1978). (United States)

    Danky, James P., Ed.; And Others

    The papers contained in this compilation were drawn from the proceedings of a 1978 conference on periodical publishing in Wisconsin. Papers in the first section of the collection deal with the basics of publishing and cover such topics as selecting articles, starting a new publication, mailing procedures, aesthetics and layout, and printing…

  2. Informed Forces for Environmental Quality, Conference Proceedings (University of Wisconsin, Green Bay, Wisconsin, March 28-29, 1968). (United States)

    Wisconsin Univ., Green Bay.

    To increase understanding of the dimensions of man's impact on his environment and the key issues involved in improving that environment through education and action was the goal of the environmental quality conference held at the University of Wisconsin, Green Bay, on March 28-29, 1968. Contained in this document are the conference…

  3. Ice cream structure modification by ice-binding proteins. (United States)

    Kaleda, Aleksei; Tsanev, Robert; Klesment, Tiina; Vilu, Raivo; Laos, Katrin


    Ice-binding proteins (IBPs), also known as antifreeze proteins, were added to ice cream to investigate their effect on structure and texture. Ice recrystallization inhibition was assessed in the ice cream mixes using a novel accelerated microscope assay and the ice cream microstructure was studied using an ice crystal dispersion method. It was found that adding recombinantly produced fish type III IBPs at a concentration 3 mg·L -1 made ice cream hard and crystalline with improved shape preservation during melting. Ice creams made with IBPs (both from winter rye, and type III IBP) had aggregates of ice crystals that entrapped pockets of the ice cream mixture in a rigid network. Larger individual ice crystals and no entrapment in control ice creams was observed. Based on these results a model of ice crystals aggregates formation in the presence of IBPs was proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. The effect of signal leakage and glacial isostatic rebound on GRACE-derived ice mass changes in Iceland

    DEFF Research Database (Denmark)

    Sørensen, Louise Sandberg; Jarosch, Alexander H.; Adalgeirsdottir, Gudfinna


    Monthly gravity field models from the GRACE satellite mission are widely used to determine ice mass changes of large ice sheets as well as smaller glaciers and ice caps. Here, we investigate in detail the ice mass changes of the Icelandic ice caps as derived from GRACE data. The small size...... find that the ice mass changes of the Icelandic ice caps derived from GRACE gravity field models are influenced by both the large gravity change signal resulting from ice mass loss in southeast Greenland and the mass redistribution within the Earth mantle due to glacial isostatic adjustment since...... the Little Ice Age (∼ 1890 AD). To minimize the signal that leaks towards Iceland from Greenland, we employ an independent mass change estimate of the Greenland Ice Sheet derived from satellite laser altimetry. We also estimate the effect of post Little Ice Age glacial isostatic adjustment, from knowledge...

  5. 76 FR 21386 - National Institute on Aging (United States)


    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute on Aging... personal privacy. Name of Committee: National Institute on Aging Special Emphasis Panel; Organelle Lifespan.... Place: National Institute on Aging, Gateway Building, 7201 Wisconsin Avenue, Suite 2C212, Bethesda, MD...

  6. 76 FR 65203 - National Institute on Aging (United States)


    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute on Aging... unwarranted invasion of personal privacy. Name of Committee: National Institute on Aging Special Emphasis... and evaluate grant applications. Place: National Institute on Aging, Gateway Building, 7201 Wisconsin...

  7. Late Pleistocene horse and camel hunting at the southern margin of the ice-free corridor: reassessing the age of Wally's Beach, Canada. (United States)

    Waters, Michael R; Stafford, Thomas W; Kooyman, Brian; Hills, L V


    The only certain evidence for prehistoric human hunting of horse and camel in North America occurs at the Wally's Beach site, Canada. Here, the butchered remains of seven horses and one camel are associated with 29 nondiagnostic lithic artifacts. Twenty-seven new radiocarbon ages on the bones of these animals revise the age of these kill and butchering localities to 13,300 calibrated y B.P. The tight chronological clustering of the eight kill localities at Wally's Beach indicates these animals were killed over a short period. Human hunting of horse and camel in Canada, coupled with mammoth, mastodon, sloth, and gomphothere hunting documented at other sites from 14,800-12,700 calibrated y B.P., show that 6 of the 36 genera of megafauna that went extinct by approximately 12,700 calibrated y B.P. were hunted by humans. This study shows the importance of accurate geochronology, without which significant discoveries will go unrecognized and the empirical data used to build models explaining the peopling of the Americas and Pleistocene extinctions will be in error.

  8. Ice and ocean velocity in the Arctic marginal ice zone: Ice roughness and momentum transfer

    Directory of Open Access Journals (Sweden)

    Sylvia T. Cole


    Full Text Available The interplay between sea ice concentration, sea ice roughness, ocean stratification, and momentum transfer to the ice and ocean is subject to seasonal and decadal variations that are crucial to understanding the present and future air-ice-ocean system in the Arctic. In this study, continuous observations in the Canada Basin from March through December 2014 were used to investigate spatial differences and temporal changes in under-ice roughness and momentum transfer as the ice cover evolved seasonally. Observations of wind, ice, and ocean properties from four clusters of drifting instrument systems were complemented by direct drill-hole measurements and instrumented overhead flights by NASA operation IceBridge in March, as well as satellite remote sensing imagery about the instrument clusters. Spatially, directly estimated ice-ocean drag coefficients varied by a factor of three with rougher ice associated with smaller multi-year ice floe sizes embedded within the first-year-ice/multi-year-ice conglomerate. Temporal differences in the ice-ocean drag coefficient of 20–30% were observed prior to the mixed layer shoaling in summer and were associated with ice concentrations falling below 100%. The ice-ocean drag coefficient parameterization was found to be invalid in September with low ice concentrations and small ice floe sizes. Maximum momentum transfer to the ice occurred for moderate ice concentrations, and transfer to the ocean for the lowest ice concentrations and shallowest stratification. Wind work and ocean work on the ice were the dominant terms in the kinetic energy budget of the ice throughout the melt season, consistent with free drift conditions. Overall, ice topography, ice concentration, and the shallow summer mixed layer all influenced mixed layer currents and the transfer of momentum within the air-ice-ocean system. The observed changes in momentum transfer show that care must be taken to determine appropriate parameterizations

  9. Sea Ice Index, Version 3 (United States)

    National Aeronautics and Space Administration — The Sea Ice Index provides a quick look at Arctic- and Antarctic-wide changes in sea ice. It is a source for consistent, up-to-date sea ice extent and concentration...

  10. Geodemographic Features of Human Blastomycosis in Eastern Wisconsin

    Directory of Open Access Journals (Sweden)

    Megan E. Huber


    Full Text Available Purpose: Blastomycosis is an endemic fungal infection. In rural northern Wisconsin, blastomycosis cases are associated with certain environmental features including close proximity to waterways. Other studies have associated blastomycosis with particular soil chemicals. However, blastomycosis also occurs in urban and suburban regions. We explored the geodemographic associations of blastomycosis cases in the more urban/suburban landscape of eastern Wisconsin. Methods: We conducted a retrospective study of 193 laboratory-identified blastomycosis cases in a single eastern Wisconsin health system, 2007–2015. Controls were 250 randomly selected cases of community-diagnosed pneumonia from a similar time period. Geographic features of home addresses were explored using Google Maps. Categorical variables were analyzed with chi-square or Fisher’s exact tests and continuous variables by two-sample t-tests. Stepwise regression followed by binary logistic regression was used for multivariable analysis. Results: Compared to pneumonia cases, blastomycosis cases were younger (47.7 vs. 55.3 years and more likely to be male (67.9% vs. 45.6%, nonwhite (23.2% vs. 9.7% and machinists, automobile workers/mechanics or construction workers (32.7% vs. 7.2%; P 0.5 acres (30.4% vs. 14.2%, P = 0.0002, be < 0.25 miles from an automobile repair facility or junkyard (35.9% vs. 19.4%, P = 0.0005, and be < 0.1 miles from a park, forest or farm field (54.9% vs. 39.6%, P = 0.002. Only the latter association remained on multivariable analysis. Conclusions: Eastern Wisconsin blastomycosis case subjects were younger, more often male and more likely to live near parks/forests/fields. Novel associations of blastomycosis cases with machinery- and automobile-related occupations and/or facilities should be further explored.

  11. Borreliosis in free-ranging black bears from Wisconsin. (United States)

    Kazmierczak, J J; Amundson, T E; Burgess, E C


    Blood, kidney and tick samples were obtained from 18 hunter-killed black bears (Ursus americanus) from three sites in northern Wisconsin. A Borrelia sp., morphologically and antigenically similar to Borrelia burgdorferi, was isolated from the blood of two of the animals, and from the kidney of a third. Ixodes dammini and Dermacentor variabilis were found on the bears. This is the first report of borreliosis in the Ursidae, and of the primary vector of Lyme disease, I. dammini, from this host.

  12. Evaluation of nonpoint-source contamination, Wisconsin: water year 1999 (United States)

    Walker, John F.; Graczyk, D.J.; Corsi, Steven R.; Wierl, J.A.; Owens, D.W.


    The objective of the watershed-management evaluation monitoring program in Wisconsin is to evaluate the effectiveness of best-management practices (BMPs) for controlling nonpoint-source pollution in rural and urban watersheds. This progress report provides a summary of the data collected by the U.S Geological Survey for the program and a discussion of the results from several different detailed analyses conducted within this program.

  13. Analysis of water-level fluctuations in Wisconsin wells (United States)

    Patterson, G.L.; Zaporozec, A.


    More than 60 percent of the residents of Wisconsin use ground water as their primary water source. Water supplies presently are abundant, but ground-water levels continually fluctuate in response to natural factors and human-related stresses. A better understanding of the magnitude, duration, and frequency of past fluctuations, and the factors controlling these fluctuations may help anticipate future changes in ground-water levels.

  14. Water resources of Wisconsin--Lake Superior basin (United States)

    Young, H.L.; Skinner, Earl L.


    This report describes the physical environment, availability, distribution, movement, quality, and use of water in the upper Wisconsin River basin as an aid in planning and water management. The report presents general information on the basin derived from data obtained from Federal, State, and local agencies, New field data were collected in areas where information was lacking. More detailed studies of problem areas may be required in the future, as water needs and related development increase.

  15. Determining climate change management priorities: A case study from Wisconsin (United States)

    LeDee, Olivia E.; Ribic, Christine


    A burgeoning dialogue exists regarding how to allocate resources to maximize the likelihood of long-term biodiversity conservation within the context of climate change. To make effective decisions in natural resource management, an iterative, collaborative, and learning-based decision process may be more successful than a strictly consultative approach. One important, early step in a decision process is to identify priority species or systems. Although this promotes the conservation of select species or systems, it may inadvertently alter the future of non-target species and systems. We describe a process to screen terrestrial wildlife for potential sensitivity to climate change and then use the results to engage natural resource professionals in a process of identifying priorities for monitoring, research, and adaptation strategy implementation. We demonstrate this approach using a case study from Wisconsin. In Wisconsin, experts identified 23 out of 353 species with sufficient empirical research and management understanding to inform targeted action. Habitat management and management of hydrological conditions were the common strategies for targeted action. Although there may be an interest in adaptation strategy implementation for many species and systems, experts considered existing information inadequate to inform targeted action. According to experts, 40% of the vertebrate species in Wisconsin will require near-term intervention for climate adaptation. These results will inform state-wide conservation planning as well as regional efforts.

  16. Rheology of glacier ice (United States)

    Jezek, K. C.; Alley, R. B.; Thomas, R. H.


    A new method for calculating the stress field in bounded ice shelves is used to compare strain rate and deviatoric stress on the Ross Ice Shelf, Antarctica. The analysis shows that strain rate (per second) increases as the third power of deviatoric stress (in newtons/sq meter), with a constant of proportionality equal to 2.3 x 10 to the -25th.

  17. Sputtering of water ice

    DEFF Research Database (Denmark)

    Baragiola, R.A.; Vidal, R.A.; Svendsen, W.


    We present results of a range of experiments of sputtering of water ice together with a guide to the literature. We studied how sputtering depends on the projectile energy and fluence, ice growth temperature, irradiation temperature and external electric fields. We observed luminescence from...

  18. Academic Airframe Icing Perspective (United States)

    Bragg, Mike; Rothmayer, Alric; Thompson, David


    2-D ice accretion and aerodynamics reasonably well understood for engineering applications To significantly improve our current capabilities we need to understand 3-D: a) Important ice accretion physics and modeling not well understood in 3-D; and b) Aerodynamics unsteady and 3-D especially near stall. Larger systems issues important and require multidisciplinary team approach

  19. Making an Ice Core. (United States)

    Kopaska-Merkel, David C.


    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)

  20. Ice sheet in peril

    DEFF Research Database (Denmark)

    Hvidberg, Christine Schøtt


    Earth's large ice sheets in Greenland and Antarctica are major contributors to sea level change. At present, the Greenland Ice Sheet (see the photo) is losing mass in response to climate warming in Greenland (1), but the present changes also include a long-term response to past climate transitions...

  1. Multiyear Arctic Ice Classification Using ASCAT and SSMIS

    Directory of Open Access Journals (Sweden)

    David B. Lindell


    Full Text Available The concentration, type, and extent of sea ice in the Arctic can be estimated based on measurements from satellite active microwave sensors, passive microwave sensors, or both. Here, data from the Advanced Scatterometer (ASCAT and the Special Sensor Microwave Imager/Sounder (SSMIS are employed to broadly classify Arctic sea ice type as first-year (FY or multiyear (MY. Combining data from both active and passive sensors can improve the performance of MY and FY ice classification. The classification method uses C-band σ0 measurements from ASCAT and 37 GHz brightness temperature measurements from SSMIS to derive a probabilistic model based on a multivariate Gaussian distribution. Using a Gaussian model, a Bayesian estimator selects between FY and MY ice to classify pixels in images of Arctic sea ice. The ASCAT/SSMIS classification results are compared with classifications using the Oceansat-2 scatterometer (OSCAT, the Equal-Area Scalable Earth Grid (EASE-Grid Sea Ice Age dataset available from the National Snow and Ice Data Center (NSIDC, and the Canadian Ice Service (CIS charts, also available from the NSIDC. The MY ice extent of the ASCAT/SSMIS classifications demonstrates an average difference of 282 thousand km - + from that of the OSCAT classifications from 2009 to 2014. The difference is an average of 13.6% of the OSCAT MY ice extent, which averaged 2.19 million km2 over the same period. Compared to the ice classified as two years or older in the EASE-Grid Sea Ice Age dataset (EASE-2+ from 2009 to 2012, the average difference is 617 thousand km2 . The difference is an average of 22.8% of the EASE-2+ MY ice extent, which averaged 2.79 million km2 from 2009 to 2012. Comparison with the Canadian Ice Service (CIS charts shows that most ASCAT/SSMIS classifications of MY ice correspond to a MY ice concentration of approximately 50% or greater in the CIS charts. The addition of the passive SSMIS data appears to improve classifications by mitigating

  2. Feasibility Report and Final Environmental Impact Statement, Wisconsin River at Portage, Wisconsin, Feasibility Study for Flood Control. Main Report. (United States)


    TABLE OF CONTRNTS (Continued) Item Page Aldo Leopold Shack EIS-43 Nonassessed Cultural Resources EIS-43...It was here, in and around his still standing cabin, that the late Aldo Leopold wrote some of his famous works. He also wrote about the immediate...the Fox-Wisconsin Portage Site (Wauona Trail); the Zona Gale House; the Old Indian Agency House; the Portage Canal; and the Aldo Leopold Shack. Four

  3. Sunlight, Sea Ice, and the Ice Albedo Feedback in a Changing Arctic Sea Ice Cover (United States)


    Figure 1). When the ice is snow covered there is little difference in albedo and partitioning between first year and multiyear ice. Once the snow melts...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Sunlight, Sea Ice, and the Ice Albedo Feedback in a...and iv) onset dates of melt and freeze up. 4. Assess the magnitude of the contribution from ice- albedo feedback to the observed decrease of sea ice

  4. Sunlight, Sea Ice, and the Ice Albedo Feedback in a Changing Artic Sea Ice Cover (United States)


    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. SUNLIGHT, SEA ICE , AND THE ICE ALBEDO FEEDBACK IN A...iv) onset dates of melt and freeze up. 4. Assess the magnitude of the contribution from ice - albedo feedback to the observed decrease of sea ice in... sea ice prediction and modeling community to improve the treatment of solar radiation and the ice - albedo feedback. This transfer will take the form of

  5. GLERL Radiation Transfer Through Freshwater Ice (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radiation transmittance (ratio of transmitted to incident radiation) through clear ice, refrozen slush ice and brash ice, from ice surface to ice-water interface in...

  6. Increasing use of firearms in completed suicides in Wisconsin, 1979-1994. (United States)

    Fox, J; Stahlsmith, L; Nashold, R; Remington, P


    Based on a review of Wisconsin suicide methods and rates from 1979 to 1994, firearms have eclipsed all other methods combined as the most common method of suicide. Between 1981 and 1992, the number of firearm suicides increased from 48% to 57%. While the overall suicide rate has remained unchanged in the last 16 years, the firearm suicide rate has increased 17% in all sexes, races and ages. For persons at known risk for suicide, removal of firearms and other lethal means from the home is recommended. Since many persons who commit suicide have not been identified as at risk, families should consider the potential risks and benefits of having a firearm in the home.

  7. Modelling snow ice and superimposed ice on landfast sea ice in Kongsfjorden, Svalbard

    Directory of Open Access Journals (Sweden)

    Caixin Wang


    Full Text Available Snow ice and superimposed ice formation on landfast sea ice in a Svalbard fjord, Kongsfjorden, was investigated with a high-resolution thermodynamic snow and sea-ice model, applying meteorological weather station data as external forcing. The model shows that sea-ice formation occurs both at the ice bottom and at the snow/ice interface. Modelling results indicated that the total snow ice and superimposed ice, which formed at the snow/ice interface, was about 14 cm during the simulation period, accounting for about 15% of the total ice mass and 35% of the total ice growth. Introducing a time-dependent snow density improved the modelled results, and a time-dependent oceanic heat flux parameterization yielded reasonable ice growth at the ice bottom. Model results suggest that weather conditions, in particular air temperature and precipitation, as well as snow thermal properties and surface albedo are the most critical factors for the development of snow ice and superimposed ice in Kongsfjorden. While both warming air and higher precipitation led to increased snow ice and superimposed ice forming in Kongsfjorden in the model runs, the processes were more sensitive to precipitation than to air temperature.

  8. High Speed Ice Friction (United States)

    Seymour-Pierce, Alexandra; Sammonds, Peter; Lishman, Ben


    Many different tribological experiments have been run to determine the frictional behaviour of ice at high speeds, ostensibly with the intention of applying results to everyday fields such as winter tyres and sports. However, experiments have only been conducted up to linear speeds of several metres a second, with few additional subject specific studies reaching speeds comparable to these applications. Experiments were conducted in the cold rooms of the Rock and Ice Physics Laboratory, UCL, on a custom built rotational tribometer based on previous literature designs. Preliminary results from experiments run at 2m/s for ice temperatures of 271 and 263K indicate that colder ice has a higher coefficient of friction, in accordance with the literature. These results will be presented, along with data from further experiments conducted at temperatures between 259-273K (in order to cover a wide range of the temperature dependent behaviour of ice) and speeds of 2-15m/s to produce a temperature-velocity-friction map for ice. The effect of temperature, speed and slider geometry on the deformation of ice will also be investigated. These speeds are approaching those exhibited by sports such as the luge (where athletes slide downhill on an icy track), placing the tribological work in context.

  9. Synchronizing ice cores from the Renland and Agassiz ice caps to the Greenland Ice Core Chronology

    DEFF Research Database (Denmark)

    Vinther, Bo Møllesøe; Clausen, Henrik Brink; Fischer, D. A.


    Four ice cores from the Agassiz ice cap in the Canadian high arctic and one ice core from the Renland ice cap in eastern Greenland have been synchronized to the Greenland Ice Core Chronology 2005 (GICC05) which is based on annual layer counts in the DYE-3, GRIP and NGRIP ice cores. Volcanic....... Annual layer thicknesses in the Agassiz ice cores point to a well-developed Raymond bump in the Agassiz ice cap....... reference horizons, seen in electrical conductivity measurements (ECM) have been used to carry out the synchronization throughout the Holocene. The Agassiz ice cores have been matched to the NGRIP ice core ECM signal, while the Renland core has been matched to the GRIP ice core ECM signal, thus tying...

  10. Initial Cooling Experiment (ICE)

    CERN Multimedia

    Photographic Service; CERN PhotoLab


    In 1977, in a record-time of 9 months, the magnets of the g-2 experiment were modified and used to build a proton/antiproton storage ring: the "Initial Cooling Experiment" (ICE). It served for the verification of the cooling methods to be used for the "Antiproton Project". Stochastic cooling was proven the same year, electron cooling followed later. Also, with ICE the experimental lower limit for the antiproton lifetime was raised by 9 orders of magnitude: from 2 microseconds to 32 hours. For its previous life as g-2 storage ring, see 7405430. More on ICE: 7711282, 7809081, 7908242.

  11. Wave-ice Interaction and the Marginal Ice Zone (United States)


    single buoys that were moved from place to place. These new data, obtained within the comprehensive set of ocean, ice and atmosphere sensors and remote...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Wave- ice interaction and the Marginal Ice Zone Prof...between ocean waves and a sea ice cover, in terms, of scattering, attenuation, and mechanical effect of the waves on the ice . OBJECTIVES The

  12. Creep of ice: further studies

    International Nuclear Information System (INIS)

    Heard, H.C.; Durham, W.B.; Kirby, S.H.


    Detailed studies have been done of ice creep as related to the icy satellites, Ganymede and Callisto. Included were: (1) the flow of high-pressure water ices II, III, and V, and (2) frictional sliding of ice I sub h. Work was also begun on the study of the effects of impurities on the flow of ice. Test results are summarized

  13. Vortex ice in nanostructured superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Reichhardt, Charles [Los Alamos National Laboratory; Reichhardt, Cynthia J [Los Alamos National Laboratory; Libal, Andras J [Los Alamos National Laboratory


    We demonstrate using numerical simulations of nanostructured superconductors that it is possible to realize vortex ice states that are analogous to square and kagome ice. The system can be brought into a state that obeys either global or local ice rules by applying an external current according to an annealing protocol. We explore the breakdown of the ice rules due to disorder in the nanostructure array and show that in square ice, topological defects appear along grain boundaries, while in kagome ice, individual defects appear. We argue that the vortex system offers significant advantages over other artificial ice systems.

  14. High-resolution paleoclimatology of the Santa Barbara Basin during the Medieval Climate Anomaly and early Little Ice Age based on diatom and silicoflagellate assemblages in Kasten core SPR0901-02KC (United States)

    Barron, John A.; Bukry, David B.; Hendy, Ingrid L.


    Diatom and silicoflagellate assemblages documented in a high-resolution time series spanning 800 to 1600 AD in varved sediment recovered in Kasten core SPR0901-02KC (34°16.845’ N, 120°02.332’ W, water depth 588 m) from the Santa Barbara Basin (SBB) reveal that SBB surface water conditions during the Medieval Climate Anomaly (MCA) and the early part of the Little Ice Age (LIA) were not extreme by modern standards, mostly falling within one standard deviation of mean conditions during the pre anthropogenic interval of 1748 to 1900. No clear differences between the character of MCA and the early LIA conditions are apparent. During intervals of extreme droughts identified by terrigenous proxy scanning XRF analyses, diatom and silicoflagellate proxies for coastal upwelling typically exceed one standard deviation above mean values for 1748-1900, supporting the hypothesis that droughts in southern California are associated with cooler (or La Niña-like) sea surface temperatures (SSTs). Increased percentages of diatoms transported downslope generally coincide with intervals of increased siliciclastic flux to the SBB identified by scanning XRF analyses. Diatom assemblages suggest only two intervals of the MCA (at ~897 to 922 and ~1151 to 1167) when proxy SSTs exceeded one standard deviation above mean values for 1748 to 1900. Conversely, silicoflagellates imply extreme warm water events only at ~830 to 860 (early MCA) and ~1360 to 1370 (early LIA) that are not supported by the diatom data. Silicoflagellates appear to be more suitable for characterizing average climate during the 5 to 11 year-long sample intervals studied in the SPR0901-02KC core than diatoms, probably because diatom relative abundances may be dominated by seasonal blooms of a particular year.

  15. Impact of the Little Ice Age cooling and 20th century climate change on peatland vegetation dynamics in central and northern Alberta using a multi-proxy approach and high-resolution peat chronologies (United States)

    Magnan, Gabriel; van Bellen, Simon; Davies, Lauren; Froese, Duane; Garneau, Michelle; Mullan-Boudreau, Gillian; Zaccone, Claudio; Shotyk, William


    Northern boreal peatlands are major terrestrial sinks of organic carbon and these ecosystems, which are highly sensitive to human activities and climate change, act as sensitive archives of past environmental change at various timescales. This study aims at understanding how the climate changes of the last 1000 years have affected peatland vegetation dynamics in the boreal region of Alberta in western Canada. Peat cores were collected from five bogs in the Fort McMurray region (56-57° N), at the southern limit of sporadic permafrost, and two in central Alberta (53° N and 55° N) outside the present-day limit of permafrost peatlands. The past changes in vegetation communities were reconstructed using detailed plant macrofossil analyses combined with high-resolution peat chronologies (14C, atmospheric bomb-pulse 14C, 210Pb and cryptotephras). Peat humification proxies (C/N, H/C, bulk density) and records of pH and ash content were also used to improve the interpretation of climate-related vegetation changes. Our study shows important changes in peatland vegetation and physical and chemical peat properties during the Little Ice Age (LIA) cooling period mainly from around 1700 CE and the subsequent climate warming of the 20th century. In some bogs, the plant macrofossils have recorded periods of permafrost aggradation during the LIA with drier surface conditions, increased peat humification and high abundance of ericaceous shrubs and black spruce (Picea mariana). The subsequent permafrost thaw was characterized by a short-term shift towards wetter conditions (Sphagnum sect. Cuspidata) and a decline in Picea mariana. Finally, a shift to a dominance of Sphagnum sect. Acutifolia (mainly Sphagnum fuscum) occurred in all the bogs during the second half of the 20th century, indicating the establishment of dry ombrotrophic conditions under the recent warmer and drier climate conditions.

  16. Microwave single-scattering properties of randomly oriented soft-ice hydrometeors

    Directory of Open Access Journals (Sweden)

    D. Casella


    Full Text Available Large ice hydrometeors are usually present in intense convective clouds and may significantly affect the upwelling radiances that are measured by satellite-borne microwave radiometers – especially, at millimeter-wavelength frequencies. Thus, interpretation of these measurements (e.g., for precipitation retrieval requires knowledge of the single scattering properties of ice particles. On the other hand, shape and internal structure of these particles (especially, the larger ones is very complex and variable, and therefore it is necessary to resort to simplifying assumptions in order to compute their single-scattering parameters.

    In this study, we use the discrete dipole approximation (DDA to compute the absorption and scattering efficiencies and the asymmetry factor of two kinds of quasi-spherical and non-homogeneous soft-ice particles in the frequency range 50–183 GHz. Particles of the first kind are modeled as quasi-spherical ice particles having randomly distributed spherical air inclusions. Particles of the second kind are modeled as random aggregates of ice spheres having random radii. In both cases, particle densities and dimensions are coherent with the snow hydrometeor category that is utilized by the University of Wisconsin – Non-hydrostatic Modeling System (UW-NMS cloud-mesoscale model. Then, we compare our single-scattering results for randomly-oriented soft-ice hydrometeors with corresponding ones that make use of: a effective-medium equivalent spheres, b solid-ice equivalent spheres, and c randomly-oriented aggregates of ice cylinders. Finally, we extend to our particles the scattering formulas that have been developed by other authors for randomly-oriented aggregates of ice cylinders.

  17. Web life: Ice Flows (United States)


    Computer and video gamers of a certain vintage will have fond memories of Lemmings, a game in which players must shepherd pixelated, suicidal rodents around a series of obstacles to reach safety. At first glance, Ice Flows is strikingly similar.

  18. Ice Engineering Research Area (United States)

    Federal Laboratory Consortium — Refrigerated Physical Modeling of Waterways in a Controlled EnvironmentThe Research Area in the Ice Engineering Facility at the Cold Regions Research and Engineering...

  19. Dead-ice environments

    DEFF Research Database (Denmark)

    Krüger, Johannes; Kjær, Kurt H.; Schomacker, Anders


    Kötlujökull transports considerable amounts of supraglacial debris at its snout because of frontal oscillations with frequent ice advances followed by ice-margin stagnation. Kötlujökull provides suitable conditions of studying dead-ice melting and landscape formation in a debris-charged lowland...... under humid, sub-polar conditions? Does this rate differ from rates reported from polar environments of dry continental nature? How will the sedimentary architecture appear in the geological record? How will the final landsystem appear? These key questions are answered in a review of research...... and conclusions on dead-ice melting and landscape formation from Kötlujökull. Processes and landform-sediment associations are linked to the current climate and glacier–volcano interaction....

  20. Global ice sheet modeling

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, T.J.; Fastook, J.L. [Univ. of Maine, Orono, ME (United States). Institute for Quaternary Studies


    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed.

  1. Global ice sheet modeling

    International Nuclear Information System (INIS)

    Hughes, T.J.; Fastook, J.L.


    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed

  2. Ice Cream Stick Math. (United States)

    Paddock, Cynthia


    Described is a teaching technique which uses the collection of ice cream sticks as a means of increasing awareness of quantity in a self-contained elementary special class for students with learning disabilities and mild mental retardation. (DB)

  3. Did ice-age bovids spread tuberculosis? (United States)

    Rothschild, Bruce M.; Martin, Larry D.


    Pathognomonic metacarpal undermining is a skeletal pathology that has been associated with Mycobacterium tuberculosis in bovids. Postcranial artiodactyl, perissodactyl, and carnivore skeletons were examined in major university and museum collections of North America and Europe for evidence of this and other pathology potentially attributable to tuberculosis. Among nonproboscidean mammals from pre-Holocene North America, bone lesions indicative of tuberculosis were restricted to immigrant bovids from Eurasia. No bone lesions compatible with diagnosis of tuberculosis were found in large samples of other pre-Holocene (164 Oligocene, 397 Miocene, and 1,041 Plio Pleistocene) North American mammals, including 114 antilocaprids. Given the unchanged frequency of bovid tubercular disease during the Pleistocene, it appears that most did not die from the disease but actually reached an accommodation with it (as did the mastodon) (Rothschild and Laub 2006). Thus, they were sufficiently long-lived to assure greater spread of the disease. The relationships of the proboscidean examples need further study, but present evidence suggests a Holarctic spread of tuberculosis during the Pleistocene, with bovids acting as vectors. While the role of other animals in the transmission of tuberculosis could be considered, the unique accommodation achieved by bovids and mastodons makes them the likely “culprits” in its spread.

  4. The genetic history of Ice Age Europe

    Czech Academy of Sciences Publication Activity Database

    Fu, Q.; Posth, C.; Hajdinjak, M.; Petr, M.; Mallick, S.; Fernandes, D.; Furtwängler, A.; Haak, W.; Meyer, M.; Mittnik, A.; Nickel, B.; Peltzer, A.; Rohland, N.; Slon, V.; Talamo, S.; Lazaridis, I.; Lipson, M.; Mathieson, I.; Schiffels, S.; Skoglund, P.; Derevianko, A. P.; Drozdov, N.; Slavinsky, V.; Tsybankov, A.; Cremonesi, R. G.; Mallegni, F.; Gély, B.; Vacca, E.; Morales, M. R. G.; Straus, L. G.; Neugebauer-Maresch, Ch.; Teschler-Nicola, M.; Constantin, S.; Moldovan, O. T.; Benazzi, S.; Peresani, M.; Coppola, D.; Lari, M.; Ricci, S.; Ronchitelli, A.; Valentin, F.; Thevenet, C.; Wehrberger, K.; Grigorescu, D.; Rougier, H.; Crevecoeur, I.; Flas, D.; Semal, P.; Mannino, M. A.; Cupillard, Ch.; Bocherens, H.; Conard, N. J.; Harvati, K.; Moiseyev, V.; Drucker, D. G.; Svoboda, Jiří; Richards, M. P.; Caramelli, D.; Pinhasi, R.; Kelso, J.; Patterson, N.; Krause, J.; Pääbo, S.; Reich, D.


    Roč. 534, č. 7606 (2016), s. 200-205 ISSN 0028-0836 Institutional support: RVO:68081758 Keywords : genetics * Pleistocene * Europe * modern humans * Neanderthal Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology Impact factor: 40.137, year: 2016

  5. The genetic history of Ice Age Europe

    DEFF Research Database (Denmark)

    Fu, Qiaomei; Posth, Cosimo; Hajdinjak, Mateja


    Modern humans arrived in Europe ~45,000 years ago, but little is known about their genetic composition before the start of farming ~8,500 years ago. Here we analyse genome-wide data from 51 Eurasians from ~45,000–7,000 years ago. Over this time, the proportion of Neanderthal DNA decreased from 3–...

  6. Heavy metals in wild rice from northern Wisconsin (United States)

    Bennett, J.P.; Chiriboga, E.; Coleman, J.; Waller, D.M.


    Wild rice grain samples from various parts of the world have been found to have elevated concentrations of heavy metals, raising concern for potential effects on human health. It was hypothesized that wild rice from north-central Wisconsin could potentially have elevated concentrations of some heavy metals because of possible exposure to these elements from the atmosphere or from water and sediments. In addition, no studies of heavy metals in wild rice from Wisconsin had been performed, and a baseline study was needed for future comparisons. Wild rice plants were collected from four areas in Bayfield, Forest, Langlade, Oneida, Sawyer and Wood Counties in September, 1997 and 1998 and divided into four plant parts for elemental analyses: roots, stems, leaves and seeds. A total of 194 samples from 51 plants were analyzed across the localities, with an average of 49 samples per part depending on the element. Samples were cleaned of soil, wet digested, and analyzed by ICP for Ag, As, Cd, Cr, Cu, Hg, Mg, Pb, Se and Zn. Roots contained the highest concentrations of Ag, As, Cd, Cr, Hg, Pb, and Se. Copper was highest in both roots and seeds, while Zn was highest just in seeds. Magnesium was highest in leaves. Seed baseline ranges for the 10 elements were established using the 95% confidence intervals of the medians. Wild rice plants from northern Wisconsin had normal levels of the nutritional elements Cu, Mg and Zn in the seeds. Silver, Cd, Hg, Cr, and Se were very low in concentration or within normal limits for food plants. Arsenic and Pb, however, were elevated and could pose a problem for human health. The pathway for As, Hg and Pb to the plants could be atmospheric.

  7. Oneida Tribe of Indians of Wisconsin Energy Optimization Model

    Energy Technology Data Exchange (ETDEWEB)

    Troge, Michael [Little Bear Development Center, Oneida, WI (United States)


    Oneida Nation is located in Northeast Wisconsin. The reservation is approximately 96 square miles (8 miles x 12 miles), or 65,000 acres. The greater Green Bay area is east and adjacent to the reservation. A county line roughly splits the reservation in half; the west half is in Outagamie County and the east half is in Brown County. Land use is predominantly agriculture on the west 2/3 and suburban on the east 1/3 of the reservation. Nearly 5,000 tribally enrolled members live in the reservation with a total population of about 21,000. Tribal ownership is scattered across the reservation and is about 23,000 acres. Currently, the Oneida Tribe of Indians of Wisconsin (OTIW) community members and facilities receive the vast majority of electrical and natural gas services from two of the largest investor-owned utilities in the state, WE Energies and Wisconsin Public Service. All urban and suburban buildings have access to natural gas. About 15% of the population and five Tribal facilities are in rural locations and therefore use propane as a primary heating fuel. Wood and oil are also used as primary or supplemental heat sources for a small percent of the population. Very few renewable energy systems, used to generate electricity and heat, have been installed on the Oneida Reservation. This project was an effort to develop a reasonable renewable energy portfolio that will help Oneida to provide a leadership role in developing a clean energy economy. The Energy Optimization Model (EOM) is an exploration of energy opportunities available to the Tribe and it is intended to provide a decision framework to allow the Tribe to make the wisest choices in energy investment with an organizational desire to establish a renewable portfolio standard (RPS).

  8. Electrical Properties of Ice (United States)


    carriers in ice. T U] P2 P3 PU4 (00C (m2 V s) (m21V S) (M21V s) (m2/V s) Method used Reference -13 to -36 (1.1±O..1)xl0𔄁 Analysis of Kunst and...Chapter 18. In Ice, 2nd ed., vol. 2. Amsterdam: North Holland Publishing Co., p. 783-7 99 . Kunst , M. and J. Warnan (1983) Nanosecond time-resolved

  9. Drugged Driving in Wisconsin: Oral Fluid Versus Blood. (United States)

    Edwards, Lorrine D; Smith, Katherine L; Savage, Theodore


    A pilot project was conducted in Dane County, Wisconsin, to evaluate the frequency of individuals driving under the influence of drugs (DUID). Evidentiary blood specimens, collected from subjects arrested for Operating While Intoxicated (OWI), were compared to oral fluid (OF) results obtained with the Alere DDS2®, a handheld screening device. The project objectives were to evaluate (i) the Alere DDS2® for use by police officers in the field, (ii) the frequency of individuals DUID and drugs combined with alcohol among OWI cases, (iii) the differences between detecting drugs in OF and in blood, and (iv) the effect of the laboratory drug testing cancellation policy (LCP) when the blood alcohol concentration (BAC) exceeds 0.100 g/100 mL. Following the arrest and collection of blood, subjects were asked to voluntarily participate in the project and provide an OF specimen. The OF was presumptively screened with the Alere DDS2® for six drug categories including (ng/mL) amphetamine (50), benzodiazepines (temazepam, 20), cocaine (benzoylecgonine, 30), methamphetamine (50), opioids (morphine, 40) and THC (delta-9-THC, 25). Results obtained with the OF screening instrument were not confirmed. A total of 104 subjects (22 female, 82 male), ages 18-72, were included in the project. Blood specimens were tested by gas chromatography-headspace (GCHS-FID) for volatiles, enzyme immunoassay (Siemens Viva-E Drug Testing System), and an alkaline basic drug screen with gas chromatography-mass spectrometry (GCMS) analysis. To compensate for differences between the EIA and the Alere DDS2® drug categories, results from the enzyme immunoassay and the alkaline basic drug screen were combined for purposes of comparing OF to blood. Seventy-six of 104 (73%) subjects arrested for OWI were driving under the influence of alcohol; 71 of the 76 had a BAC exceeding 0.10 g/100 mL. Subjects with a BAC exceeding the LCP, screened positive for drugs in both OF (n = 29) and blood (n = 28). Overall, one

  10. Analysis of nursing home use and bed supply: Wisconsin, 1983.


    Nyman, J A


    This article presents evidence that in 1983 excess demand was a prevailing characteristic of nursing home care markets in Wisconsin, a state with one of the highest bed to elderly population ratios. It further shows that excess demand is the source of at least three types of error in use-based estimates of the determinants of the need for nursing home care. First, if excess demand is present, estimates of the determinants of Medicaid use may simply represent a crowding out of Medicaid patient...

  11. Simulated Performance of the Wisconsin Superconducting Electron Gun

    Energy Technology Data Exchange (ETDEWEB)

    R.A. Bosch, K.J. Kleman, R.A. Legg


    The Wisconsin superconducting electron gun is modeled with multiparticle tracking simulations using the ASTRA and GPT codes. To specify the construction of the emittance-compensation solenoid, we studied the dependence of the output bunch's emittance upon the solenoid's strength and field errors. We also evaluated the dependence of the output bunch's emittance upon the bunch's initial emittance and the size of the laser spot on the photocathode. The results suggest that a 200-pC bunch with an emittance of about one mm-mrad can be produced for a free-electron laser.

  12. Ice slurry accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, K.G.; Kauffeld, M.


    More and more refrigeration systems are designed with secondary loops, thus reducing the refrigerant charge of the primary refrigeration plant. In order not to increase energy consumption by introducing a secondary refrigerant, alternatives to the well established single phase coolants (brines) and different concepts of the cooling plant have to be evaluated. Combining the use of ice-slurry - mixture of water, a freezing point depressing agent (antifreeze) and ice particles - as melting secondary refrigerant and the use of a cool storage makes it possible to build plants with secondary loops without increasing the energy consumption and investment. At the same time the operating costs can be kept at a lower level. The accumulation of ice-slurry is compared with other and more traditional storage systems. The method is evaluated and the potential in different applications is estimated. Aspects of practically use of ice-slurry has been examined in the laboratory at the Danish Technological Institute (DTI). This paper will include the final conclusions from this work concerning tank construction, agitator system, inlet, outlet and control. The work at DTI indicates that in some applications systems with ice-slurry and accumulation tanks have a great future. These applications are described by a varying load profile and a process temperature suiting the temperature of ice-slurry (-3 - -8/deg. C). (au)

  13. Co-distribution of seabirds and their polar cod prey near the ice edge in southern Baffin Bay

    DEFF Research Database (Denmark)

    LeBlanc, Mathieu; Gauthier, S; Mosbech, Anders

    species, and age-1 polar cod found in bird stomachs were likely individuals associated to ice. At a large scale of hundreds of kilometers, seabirds and age-0 polar cod were more abundant in ice-covered habitats (30 to 100% ice concentration). At medium and small scale of 12.5 and 1 km respectively...

  14. Northern red oak volume growth on four northern Wisconsin habitat types (United States)

    Michael Demchik; Kevin M. Schwartz; Rory Braun; Eric. Scharenbrock


    Northern red oak (Quercus rubra) grows across much of Wisconsin. Using site factors to aid in prediction of volume and basal area increment facilitates management of red oak and other species of interest. Currently, habitat type (Wisconsin Habitat Type Classification System) is often determined when stands are inventoried. If habitat type were...

  15. 78 FR 65875 - Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Removal of Gasoline... (United States)


    ...] Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Removal of Gasoline Vapor... Administrative Code, Chapter NR 420 Control of Organic Compound Emissions from Petroleum and Gasoline Sources... FROM PETROLEUM AND GASOLINE SOURCES. NR 420.01 as published in the (Wisconsin) Register, February, 1990...

  16. Estimating outside-bark stem volume to any top diameter for ash in Wisconsin (United States)

    Paul F. Doruska; Timothy D. Hart


    The future of Wisconsin's estimated 742 million ash trees (5 million of which are in urban settings composing 20 percent of Wisconsin's urban forests) is being considered based on the presence of the emerald ash borer. Part of this discussion includes the stem volumes of these ash trees.

  17. Tree seed handling, processing, testing, and storage at Hayward State Nursery, Wisconsin Department of Natural Resources (United States)

    Gordon Christians


    The Hayward State Nursery, Wisconsin grows more than 40 species from seeds. Up to 6000 bushels of raw unprocessed tree and shrub seeds are collected each year, and all seeds are collected in Wisconsin or adjacent states. All white spruce (Picea glauca) and some white pine seeds (Pinus strobus) are collected from orchards containing...

  18. 75 FR 71108 - Wisconsin Public Service Corporation; Notice of Application for Amendment of License and... (United States)


    ... Energy Regulatory Commission Wisconsin Public Service Corporation; Notice of Application for Amendment of... Filed: June 30, 2010. d. Applicant: Wisconsin Public Service Corporation. e. Name of Project: Tomahawk... the following hydroelectric application has been filed with the Commission and is available for public...

  19. 77 FR 40608 - Wisconsin Electric Power Company; Notice of Petition for Declaratory Order (United States)


    ... accounting treatment of a coal contract buydown; and (2) waiver of the Commission's fuel clause regulation to allow Wisconsin Electric to recoup the cost of the coal contract buydown through Wisconsin Electric's cost-based, Formula Rate Wholesale Sales Tariff. Any person desiring to intervene or to protest this...

  20. 78 FR 48900 - Notice of Inventory Completion: State Historical Society of Wisconsin, Madison, WI (United States)


    .... 3003, of the completion of an inventory of human remains under the control of the State Historical....R50000] Notice of Inventory Completion: State Historical Society of Wisconsin, Madison, WI AGENCY... Wisconsin has completed an inventory of human remains, in consultation with the appropriate Indian tribes or...

  1. 40 CFR 81.30 - Southeastern Wisconsin Intrastate Air Quality Control Region. (United States)


    ... Quality Control Region. 81.30 Section 81.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Air Quality Control Regions § 81.30 Southeastern Wisconsin Intrastate Air Quality Control Region. The Metropolitan Milwaukee Intrastate Air Quality Control Region (Wisconsin) has been renamed the Southeastern...

  2. 78 FR 44596 - Notice of Inventory Completion: State Historical Society of Wisconsin, Madison, WI (United States)


    ... address in this notice by August 23, 2013. ADDRESSES: Jennifer Kolb, Wisconsin Historical Museum, 30 North Carroll Street, Madison, WI 53703, telephone (608) 261-2461, email request to Jennifer Kolb, Wisconsin Historical Museum, 30 North Carroll Street, Madison, WI 53703...

  3. Revolution and Counter-Revolution: Network Mobilization to Preserve Public Education in Wisconsin (United States)

    Kelley, Carolyn; Mead, Julie


    In this article, Kelley and Mead consider changes in the policymaking process in Wisconsin before the election of Governor Walker, in the early years following his election, and in the months preceding passage of the 2015-17 biennial budget. Kelley and Mead argue that in Wisconsin, serious and significant attacks to public education motivated by…

  4. Environmental Factors Influencing White-Tailed Deer (Odocoileus virginianus Exposure to Livestock Pathogens in Wisconsin.

    Directory of Open Access Journals (Sweden)

    Shelli Dubay

    Full Text Available White-tailed deer (Odocoileus virginianus are commonly exposed to disease agents that affect livestock but environmental factors that predispose deer to exposure are unknown for many pathogens. We trapped deer during winter months on two study areas (Northern Forest and Eastern Farmland in Wisconsin from 2010 to 2013. Deer were tested for exposure to six serovars of Leptospira interrogans (grippotyphosa, icterohaemorrhagiae, canicola, bratislava, pomona, and hardjo, bovine viral diarrhea virus (BVDV-1 and BVDV-2, infectious bovine rhinotracheitis virus (IBR, and parainfluenza 3 virus (PI3. We used logistic regression to model potential intrinsic (e.g., age, sex and extrinsic (e.g., land type, study site, year, exposure to multiple pathogens variables we considered biologically meaningful to exposure of deer to livestock pathogens. Deer sampled in 2010-2011 did not demonstrate exposure to BVDV, so we did not test for BVDV in subsequent years. Deer had evidence of exposure to PI3 (24.7%, IBR (7.9%, Leptospira interrogans serovar pomona (11.7%, L. i. bratislava (1.0%, L. i. grippotyphosa (2.5% and L. i. hardjo (0.3%. Deer did not demonstrate exposure to L. interrogans serovars canicola and icterohaemorrhagiae. For PI3, we found that capture site and year influenced exposure. Fawns (n = 119 were not exposed to L. i. pomona, but land type was an important predictor of exposure to L. i. pomona for older deer. Our results serve as baseline exposure levels of Wisconsin white-tailed deer to livestock pathogens, and helped to identify important factors that explain deer exposure to livestock pathogens.

  5. Ice recrystallization inhibition in ice cream by propylene glycol monostearate. (United States)

    Aleong, J M; Frochot, S; Goff, H D


    The effectiveness of propylene glycol monostearate (PGMS) to inhibit ice recrystallization was evaluated in ice cream and frozen sucrose solutions. PGMS (0.3%) dramatically reduced ice crystal sizes in ice cream and in sucrose solutions frozen in a scraped-surface freezer before and after heat shock, but had no effect in quiescently frozen solutions. PGMS showed limited emulsifier properties by promoting smaller fat globule size distributions and enhanced partial coalescence in the mix and ice cream, respectively, but at a much lower level compared to conventional ice cream emulsifier. Low temperature scanning electron microscopy revealed highly irregular crystal morphology in both ice cream and sucrose solutions frozen in a scraped-surface freezer. There was strong evidence to suggest that PGMS directly interacts with ice crystals and interferes with normal surface propagation. Shear during freezing may be required for its distribution around the ice and sufficient surface coverage.

  6. Demonstration of the Whole-Building Diagnostician for the Federal Building and U.S. Courthouse at Milwaukee, Wisconsin, and for the University of Wisconsin at Madison

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, Nathan N.; Hail, John C.


    In an effort to expand the energy savings programs within the State, the Wisconsin Division of Energy obtained funding through the Federal Energy Management Program (FEMP), with additional funding assistance through the Rebuild America Program (RBA) to install the Whole Building Diagnostician (WBD) software program as a test bed project in two of the State’s facilities in Wisconsin. This report discusses the results of this effort.

  7. Evaluation of Little Ice Age cooling in Western Central Andes, suggested by paleoELAs, in contrast with global warming since late 19th century deduced from instrumental records (United States)

    Ubeda, Jose; Palacios, David; Campos, Néstor; Giraldez, Claudia; García, Eduardo; Quiros, Tatiana


    This paper attempts to evaluate climate cooling (°C) during the glacial expansion phases using the product GTV•ΔELA, where GTV is the vertical air temperature gradient (°C/m) and ΔELA (m) the difference in level observed between the Equilibrium Line Altitude (ELA) reconstructions for current and past glaciers. With this aim the Area x Altitude Balance Ratio-(AABR) method was used to produce reconstructions of present ELAs (2002-2010) and paleoELAs corresponding to the last glacier advance phase. The reconstructions were produced in three study areas located along a N-S transect of the western cordillera in the Central Andes: the south-western sector of the Nevado Hualcán (9°S, 77°W; Giráldez 2011); the southern slope of the Cordillera Pariaqaqa (12°S, 76°W; Quirós, 2013) and the NW, NE, SE and SW quadrants of the Nevado Coropuna (16°S, 72°W; García 2013; Úbeda 2011; Campos, 2012). The three mountains exceed 6000 m altitude, their summit areas are covered by glaciers, and on their slopes there are existing well-conserved moraines deposited by the last advances near the present front of the ice masses. Although there are no absolute dates to confirm this hypothesis, it has been assumed that the last glacial advances occurred during the Little Ice Age (LIA), which the oxygen isotopes of the Nevado Huascarán (9°S, 77°W) date to the period 1500-1890. For the Hualcán and Pariaqaqa the mean global value of the Earth's GTV (6.5°C/km) was used, considered valid for the Tropics. On the Coropuna a GTV=8.4°C/km was used, based on high resolution sensors installed in situ since 2007 (Úbeda 2011). This gradient is approaching the upper limit of the dry adiabatic gradient (9.8°C/km), as the Coropuna region is more arid than the other case study areas. The climate cooling estimates deduced from the product GTV•ΔELA were compared with the global warming shown by the 1880-2012 series, ΔT=0.85°C, and 1850/1900-2003/2012, ΔT=0.78°C. The differences are

  8. Methodological synergies for glaciological constraints to find Oldest Ice (United States)

    Eisen, Olaf


    The Beyond EPICA - Oldest Ice (BE-OI) consortium and its international partners unite a globally unique concentration of scientific expertise and infrastructure for ice-core investigations. It delivers the technical, scientific and financial basis for a comprehensive plan to retrieve an ice core up to 1.5 million years old. The consortium takes care of the pre-site surveys for site selection around Dome C and Dome Fuji, both potentially appropriate regions in East Antarctica. Other science consortia will investigate other regions under the umbrella of the International Partnerships in Ice Core Sciences (IPICS). Of major importance to obtain reliable estimates of the age of the ice in the basal layers of the ice sheet are the physical boundary conditions and ice-flow dynamics: geothermal heat flux, advection and layer integrity to avoid layer overturning and the formation of folds. The project completed the first field season at both regions of interest. This contribution will give an overview how the combined application of various geophysical, geodetical and glaciological methods applied in the field in combination with ice-flow modelling can constrain the glaciological boundary conditions and thus age at depth.

  9. Neoglacial ice expansion and late Holocene cold-based ice cap dynamics on Cumberland Peninsula, Baffin Island, Arctic Canada (United States)

    Margreth, Annina; Dyke, Arthur S.; Gosse, John C.; Telka, Alice M.


    Radiocarbon dating of fossil flora and fauna collected along receding cold-based ice caps and cold-based sections of polythermal glaciers on Cumberland Peninsula reveal insights into Neoglacial ice expansion and late Holocene ice dynamics. The taphonomic advantages of subfossilized moss were exploited to precisely document regional expansions of ice caps through the late Holocene. When compared with climate proxies and records of volcanic eruptions, the moss radiocarbon age distributions indicate i) onset of Neoglaciation shortly after 5 ka, concomitant with increased sea ice cover, ii) intensification of ice expansion between 1.9 and 1.1 ka, followed by halt of ice growth, or ice recession during the Medieval Warm Period, and iii) renewed ice expansion after 0.8 ka, in response to cooling related to a combination of large volcanic eruptions and low solar activity. Overall, the observations support a model of near-instantaneous glacial response to regional climate controls and that these responses were synchronous throughout eastern Canadian Arctic and possibly eastern Greenland.

  10. Ice Formation of Coated Black Carbon Particles (United States)

    Friedman, B.; Kulkarni, G.; Beránek, J.; Zelenyuk, A.; Cziczo, D. J.; Thornton, J. A.


    The importance of black carbon particles as heterogeneous ice nuclei is currently in question. While pure black carbon is hydrophobic, atmospheric processing or aging by condensation or heterogeneous oxidation may alter the surface, physical and chemical properties, likely causing the particle surface and perhaps the particle bulk to become more hydrophilic. The impact of such atmospheric processing on the ice nucleating ability of soot remains poorly explored. In this laboratory study we simulated various atmospheric processing mechanisms and their effect on the ice formation of black carbon particles. Black carbon particles were generated by both dry powder dispersion of commercial carbon black and using a miniCAST soot generator. The particles were then coated with various atmospherically relevant coatings, including dicarboxylic acids of varying solubility. The ice-forming potential of the resulting particles was continuously determined at heterogeneous conditions in the PNNL Compact Ice Chamber. Single Particle Mass Spectrometer (SPLAT) was used to characterize the size, chemical composition, morphology, fractal dimension, and effective densities of individual particles with and without the coatings and to quantify the relationship between particle chemical and physical properties and their IN activity. We discuss the implications of our results in the context of typical lifetimes and processing history experienced by black carbon particles emitted into the upper troposphere.

  11. Characteristics of ice, needed for ice loadings determination

    Directory of Open Access Journals (Sweden)

    Polit’ko Valentin Aleksandrovich


    Full Text Available In order to determine ice loads on the offshore oil and gas structures different ice information is required as an input data. At the present moment there is no unified generally recognized methodology for estimating ice loads and set the main ice parameters. In this relation there appears a question of the ice parameters which need to be investigated. The article attempts to analyze a variety of sources, including standards, on the subject of collection of ice information, required and sufficient for the calculation of ice loads. The article presents the basic steps in the planning of ice information collection, the list of main characteristics and parameters of ice, modern methods of observations and direct measurements of the ice, as well as the ways in which the field tests data of physical and mechanical properties of ice is processed. Particular attention is paid to the anisotropy of ice, integrated assessment of the strength of the ice field, as well as the variability of meteorological conditions.

  12. Atmospheric forcing of sea ice anomalies in the Ross Sea Polynya region (United States)

    Dale, Ethan; McDonald, Adrian; Rack, Wolfgang


    Despite warming trends in global temperatures, sea ice extent in the southern hemisphere has shown an increasing trend over recent decades. Wind-driven sea ice export from coastal polynyas is an important source of sea ice production. Areas of major polynyas in the Ross Sea, the region with largest increase in sea ice extent, have been suggested to produce the vast amount of the sea ice in the region. We investigate the impacts of strong wind events on polynyas and the subsequent sea ice production. We utilize Bootstrap sea ice concentration (SIC) measurements derived from satellite based, Special Sensor Microwave Imager (SSM/I) brightness temperature images. These are compared with surface wind measurements made by automatic weather stations of the University of Wisconsin-Madison Antarctic Meteorology Program. Our analysis focusses on the winter period defined as 1st April to 1st November in this study. Wind data was used to classify each day into characteristic regimes based on the change of wind speed. For each regime, a composite of SIC anomaly was formed for the Ross Sea region. We found that persistent weak winds near the edge of the Ross Ice Shelf are generally associated with positive SIC anomalies in the Ross Sea polynya area (RSP). Conversely we found negative SIC anomalies in this area during persistent strong winds. By analyzing sea ice motion vectors derived from SSM/I brightness temperatures, we find significant sea ice motion anomalies throughout the Ross Sea during strong wind events. These anomalies persist for several days after the strong wing event. Strong, negative correlations are found between SIC within the RSP and wind speed indicating that strong winds cause significant advection of sea ice in the RSP. This rapid decrease in SIC is followed by a more gradual recovery in SIC. This increase occurs on a time scale greater than the average persistence of strong wind events and the resulting Sea ice motion anomalies, highlighting the production

  13. Sea Ice - The overlooked Player in the Arctic Methane Cycle (United States)

    Damm, E.


    Methane is a greenhouse gas and increasing atmospheric concentrations contribute to trigger global warming. The Arctic hosts large natural methane sources and is expected to be a region where warming feeds warming, i.e. temperature changes may quickly induce enhanced methane emissions. This Arctic amplification of global warming has led to increased summer sea ice retreat, thinning sea ice and decreasing multiyear and increasing one-year sea ice. Hence as feedback to a feedback, sea ice loss will have until now unforeseen consequences for methane efflux while as well as sea ice-ocean interactions and shelf-ocean links have to be taken into account. I will present an overview of multiple direct and indirect effects of sea ice on the marine methane cycle not yet counted. Arctic shelf water is reported to be methane super-saturated in summer. Hence an important interaction between sea ice and methane is to be expected when sea ice formation on shelves induces super-saturated brine which will be enclosed in sea ice during winter and released in spring during melt. It will be shown that especially Polynya regions allow studying the effect of strong ice formation in winter which generate deep convection and resuspension of sediments with subsequent methane release. Once released, then methane may either directly escape to the atmosphere or remain trapped in sea ice. The further fate of the enclosed methane is closely coupled to the fate of the sea ice. Hence thinning and shifts in sea ice-age will be pivotal for methane cycling. Sea ice drift may transport shelf- released methane to remote locations in the interior Arctic where the cascade of freezing and melting events triggers the level of super-saturation in Polar surface water below. To date these kinds of sea ice-ocean interaction processes initially induced by shelf-released methane are the most unknown boxes in calculating the methane budget. Considering these pathways instead of efflux estimations calculated by


    Directory of Open Access Journals (Sweden)

    Dana Lori Chalmers


    Full Text Available Ideologically Challenging Entertainment (ICE is entertainment that challenges ‘us vs. them’ ideologies associated with radicalization, violent conflict and terrorism. ICE presents multiple perspectives on a conflict through mainstream entertainment. This article introduces the theoretical underpinnings of ICE, the first ICE production and the audience responses to it. The first ICE production was Two Merchants: The Merchant of Venice adapted to challenge ideologies of the Arab-Israeli Conflict. A mixed-methods study of audience responses explored whether this production inspired audiences to shift their ideological views. Each performance included two versions of the adaptation: a Jewish dominated society with an Arab Muslim minority, contrasted with an Arab Muslim dominated society and a Jewish minority. A mixed-methods study of audience responses explored whether this production inspired audiences to shift their ideological views to become more tolerant of differences away from ideological radicalization. Of audience members who did not initially agree with the premise of the production, 40% reconsidered their ideological views, indicating increased tolerance, greater awareness of and desire to change their own prejudices. In addition, 86% of the audience expressed their intention to discuss the production with others, thereby encouraging critical engagement with, and broader dissemination of the message. These outcomes suggest that high quality entertainment – as defined by audience responses to it - can become a powerful tool in the struggle against radicalised ideologies.

  15. Data archaeology at ICES (United States)

    Dooley, Harry D.


    This paper provides a brief overview of the function of the International Council for the Exploration of the Sea (ICES), both past and present, in particular in the context of its interest in compiling oceanographic data sets. Details are provided of the procedures it adopted to ensure adequate internationally collaborative marine investigations during the first part of the century, such as how it provided a forum for action by its member states, how it coordinated and published the results of scientific programs, and how it provided a foundation, through scientists employed in the ICES Office, for the establishment of the original oceanographic marine databases and associated products, and the scientific interpretation of the results. The growth and expansion of this area of ICES activity is then traced, taking into account the changing conditions for oceanographic data management resulting from the establishment of the National Data Centres, as well as the World Data Centres for Oceanography, which were created to meet the needs of the International Geophysical Year (IGY). Finally, there is a discussion of the way in which the very existence of ICES has proved to be a valuable source of old data, some of which have not yet been digitized, but which can be readily retrieved because they have been very carefully documented throughout the years. Lessons from this activity are noted, and suggestions are made on how the past experiences of ICES can be utilized to ensure the availability of marine data to present and future generations of scientists.

  16. Provisioning rates and time budgets of adult and nestling Bald Eagles at Inland Wisconsin nests (United States)

    Keith, Warnke D.; Andersen, D.E.; Dykstra, C.R.; Meyer, M.W.; Karasov, W.H.


    We used a remote video recording system and direct observation to quantify provisioning rate and adult and nestling behavior at Bald Eagle (Haliaeetus leucocephalus) nests in north-central Wisconsin in 1992 (N = 5) and 1993 (N = 8). Eagles nesting in this region have a high reproductive rate (??? 1.3 young/occupied territory), and the number of occupied territories has expanded nearly three-fold since 1980. The season-long provisioning rate averaged 5.2 prey deliveries/nest/d and 3.0 prey deliveries/nestling/d, and did not vary by year or with nestling number or age. Fish (Osteichthyes) made up 97% of identified prey deliveries followed by reptiles (Reptilia) (1.5%), birds (Aves) (1.2%), and mammals (Mammalia) (0.6%). Nearly 85% of prey items were >15 cm and 90% of the day and was negatively correlated with nestling age. Time adults spent feeding nestlings was negatively correlated with nestling age. Nestlings stood or sat in the nest >30% of the day, began to feed themselves, and exhibited increased mobility in the nest at 6-8 wk. We identified three stages of the nestling period and several benchmarks that may be useful when scheduling data collection for comparison of Bald Eagle nesting behavior. Our results support the hypothesis that food was not limiting this breeding population of Bald Eagles. ?? 2002 The Raptor Research Foundation, Inc.

  17. IceBridge PARIS L2 Ice Thickness V001 (United States)

    National Aeronautics and Space Administration — This data set contains contains Greenland ice thickness measurements acquired using the Pathfinder Advanced Radar Ice Sounder (PARIS).The data were collected as part...

  18. Thin ice and storms: Sea ice deformation from buoy arrays deployed during N-ICE2015


    Itkin, Polona; Spreen, Gunnar; Cheng, Bin; Doble, Martin; Girard-Ardhuin, Fanny; Haapala, Jari; Hughes, Nick; Kaleschke, Lars; Nicolaus, Marcel; Wilkinson, Jeremy


    Arctic sea ice has displayed significant thinning as well as an increase in drift speed in recent years. Taken together this suggests an associated rise in sea ice deformation rate. A winter and spring expedition to the sea ice covered region north of Svalbard – the Norwegian young sea ICE 2015 expedition (N-ICE2015) - gave an opportunity to deploy extensive buoy arrays and to monitor the deformation of the first- and second-year ice now common in the majority of the Arctic Basin. During the ...

  19. Experimental Analysis of Sublimation Dynamics for Buried Glacier Ice in Beacon Valley, Antarctica (United States)

    Ehrenfeucht, S.; Dennis, D. P.; Marchant, D. R.


    The age of the oldest known buried ice in Beacon Valley, McMurdo Dry Valleys (MDV) Antarctica is a topic of active debate due to its implications for the stability of the East Antarctic Ice Sheet. Published age estimates range from as young as 300 ka to as old as 8.1 Ma. In the upland MDV, ablation occurs predominantly via sublimation. The relict ice in question (ancient ice from Taylor Glacier) lies buried beneath a thin ( 30-70 cm) layer of sublimation till, which forms as a lag deposit as underlying debris-rich ice sublimes. As the ice sublimates, the debris held within the ice accumulates slowly on the surface, creating a porous boundary between the buried-ice surface and the atmosphere, which in turn influences gas exchange between the ice and the atmosphere. Additionally, englacial debris adds several salt species that are ultimately concentrated on the ice surface. It is well documented the rate of ice sublimation varies as a function of overlying till thickness. However, the rate-limiting dynamics under varying environmental conditions, including the threshold thicknesses at which sublimation is strongly retarded, are not yet defined. To better understand the relationships between sublimation rate, till thickness, and long-term surface evolution, we build on previous studies by Lamp and Marchant (2017) and evaluate the role of till thickness as a control on ice loss in an environmental chamber capable of replicating the extreme cold desert conditions observed in the MDV. Previous work has shown that this relationship exhibits exponential decay behavior, with sublimation rate significantly dampened under less than 10 cm of till. In our experiments we pay particular attention to the effect of the first several cm of till in order to quantify the dynamics that govern the transition from bare ice to debris-covered ice. We also examine this transition for various forms of glacier ice, including ice with various salt species.

  20. Dry Ice Etches Terrain (United States)


    [figure removed for brevity, see original site] Figure 1 Every year seasonal carbon dioxide ice, known to us as 'dry ice,' covers the poles of Mars. In the south polar region this ice is translucent, allowing sunlight to pass through and warm the surface below. The ice then sublimes (evaporates) from the bottom of the ice layer, and carves channels in the surface. The channels take on many forms. In the subimage shown here (figure 1) the gas from the dry ice has etched wide shallow channels. This region is relatively flat, which may be the reason these channels have a different morphology than the 'spiders' seen in more hummocky terrain. Observation Geometry Image PSP_003364_0945 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 15-Apr-2007. The complete image is centered at -85.4 degrees latitude, 104.0 degrees East longitude. The range to the target site was 251.5 km (157.2 miles). At this distance the image scale is 25.2 cm/pixel (with 1 x 1 binning) so objects 75 cm across are resolved. The image shown here has been map-projected to 25 cm/pixel . The image was taken at a local Mars time of 06:57 PM and the scene is illuminated from the west with a solar incidence angle of 75 degrees, thus the sun was about 15 degrees above the horizon. At a solar longitude of 219.6 degrees, the season on Mars is Northern Autumn.

  1. Submesoscale Sea Ice-Ocean Interactions in Marginal Ice Zones (United States)

    Manucharyan, Georgy E.; Thompson, Andrew F.


    Signatures of ocean eddies, fronts, and filaments are commonly observed within marginal ice zones (MIZs) from satellite images of sea ice concentration, and in situ observations via ice-tethered profilers or underice gliders. However, localized and intermittent sea ice heating and advection by ocean eddies are currently not accounted for in climate models and may contribute to their biases and errors in sea ice forecasts. Here, we explore mechanical sea ice interactions with underlying submesoscale ocean turbulence. We demonstrate that the release of potential energy stored in meltwater fronts can lead to energetic submesoscale motions along MIZs with spatial scales O(10 km) and Rossby numbers O(1). In low-wind conditions, cyclonic eddies and filaments efficiently trap the sea ice and advect it over warmer surface ocean waters where it can effectively melt. The horizontal eddy diffusivity of sea ice mass and heat across the MIZ can reach O(200 m2 s-1). Submesoscale ocean variability also induces large vertical velocities (order 10 m d-1) that can bring relatively warm subsurface waters into the mixed layer. The ocean-sea ice heat fluxes are localized over cyclonic eddies and filaments reaching about 100 W m-2. We speculate that these submesoscale-driven intermittent fluxes of heat and sea ice can contribute to the seasonal evolution of MIZs. With the continuing global warming and sea ice thickness reduction in the Arctic Ocean, submesoscale sea ice-ocean processes are expected to become increasingly prominent.

  2. Centuries of intense surface melt on Larsen C Ice Shelf (United States)

    Bevan, Suzanne L.; Luckman, Adrian; Hubbard, Bryn; Kulessa, Bernd; Ashmore, David; Kuipers Munneke, Peter; O'Leary, Martin; Booth, Adam; Sevestre, Heidi; McGrath, Daniel


    Following a southward progression of ice-shelf disintegration along the Antarctic Peninsula (AP), Larsen C Ice Shelf (LCIS) has become the focus of ongoing investigation regarding its future stability. The ice shelf experiences surface melt and commonly features surface meltwater ponds. Here, we use a flow-line model and a firn density model (FDM) to date and interpret observations of melt-affected ice layers found within five 90 m boreholes distributed across the ice shelf. We find that units of ice within the boreholes, which have densities exceeding those expected under normal dry compaction metamorphism, correspond to two climatic warm periods within the last 300 years on the Antarctic Peninsula. The more recent warm period, from the 1960s onwards, has generated distinct sections of dense ice measured in two boreholes in Cabinet Inlet, which is close to the Antarctic Peninsula mountains - a region affected by föhn winds. Previous work has classified these layers as refrozen pond ice, requiring large quantities of mobile liquid water to form. Our flow-line model shows that, whilst preconditioning of the snow began in the late 1960s, it was probably not until the early 1990s that the modern period of ponding began. The earlier warm period occurred during the 18th century and resulted in two additional sections of anomalously dense ice deep within the boreholes. The first, at 61 m in one of our Cabinet Inlet boreholes, consists of ice characteristic of refrozen ponds and must have formed in an area currently featuring ponding. The second, at 69 m in a mid-shelf borehole, formed at the same time on the edge of the pond area. Further south, the boreholes sample ice that is of an equivalent age but which does not exhibit the same degree of melt influence. This west-east and north-south gradient in the past melt distribution resembles current spatial patterns of surface melt intensity.

  3. Vacancy Concentration in Ice

    DEFF Research Database (Denmark)

    Mogensen, O. E.; Eldrup, Morten Mostgaard


    Based on the diffusion constant for self-diffusion in ice, which is believed to take place by a vacancy mechanism, we estimate the relative vacancy concentration near the melting point to be at least ∼ 10−6, i.e. much higher than previous estimates of about 10−10.......Based on the diffusion constant for self-diffusion in ice, which is believed to take place by a vacancy mechanism, we estimate the relative vacancy concentration near the melting point to be at least ∼ 10−6, i.e. much higher than previous estimates of about 10−10....


    DEFF Research Database (Denmark)

    Andersen, Søren; Tonboe, Rasmus; Heygster, Georg


    and determine the circumstances that may lead to anomalous sea ice concentration retrieval as well as to assess and possibly minimize the sensitivities of the retrieval system. Through an active partnership with the SAF on Ocean and Sea Ice, a prototype system will be implemented as an experimental product...... chain in order to shorten the loop from development to operational processing. The presentation will present the developments and examples of the new retrievals and finally give an outlook to the future perspectives of the system....

  5. Safety hazard of aircraft icing (United States)

    Mclean, J. C., Jr.


    The problem of aircraft icing is reported as well as the type of aircraft affected, the pilots involved, and an identification of the areas where reduction in icing accidents are readily accomplished.

  6. ICE Online Detainee Locator System (United States)

    Department of Homeland Security — The Online Detainee Locator datasets provide the location of a detainee who is currently in ICE custody, or who was release from ICE custody for any reason with the...

  7. Pre-LGM Northern Hemisphere ice sheet topography

    Directory of Open Access Journals (Sweden)

    J. Kleman


    Full Text Available We here reconstruct the paleotopography of Northern Hemisphere ice sheets during the glacial maxima of marine isotope stages (MIS 5b and 4.We employ a combined approach, blending geologically based reconstruction and numerical modeling, to arrive at probable ice sheet extents and topographies for each of these two time slices. For a physically based 3-D calculation based on geologically derived 2-D constraints, we use the University of Maine Ice Sheet Model (UMISM to calculate ice sheet thickness and topography. The approach and ice sheet modeling strategy is designed to provide robust data sets of sufficient resolution for atmospheric circulation experiments for these previously elusive time periods. Two tunable parameters, a temperature scaling function applied to a spliced Vostok–GRIP record, and spatial adjustment of the climatic pole position, were employed iteratively to achieve a good fit to geological constraints where such were available. The model credibly reproduces the first-order pattern of size and location of geologically indicated ice sheets during marine isotope stages (MIS 5b (86.2 kyr model age and 4 (64 kyr model age. From the interglacial state of two north–south obstacles to atmospheric circulation (Rocky Mountains and Greenland, by MIS 5b the emergence of combined Quebec–central Arctic and Scandinavian–Barents-Kara ice sheets had increased the number of such highland obstacles to four. The number of major ice sheets remained constant through MIS 4, but the merging of the Cordilleran and the proto-Laurentide Ice Sheet produced a single continent-wide North American ice sheet at the LGM.

  8. Ice recrystallization inhibition in ice cream as affected by ice structuring proteins from winter wheat grass. (United States)

    Regand, A; Goff, H D


    Ice recrystallization in quiescently frozen sucrose solutions that contained some of the ingredients commonly found in ice cream and in ice cream manufactured under commercial conditions, with or without ice structuring proteins (ISP) from cold-acclimated winter wheat grass extract (AWWE), was assessed by bright field microscopy. In sucrose solutions, critical differences in moisture content, viscosity, ionic strength, and other properties derived from the presence of other ingredients (skim milk powder, corn syrup solids, locust bean gum) caused a reduction in ice crystal growth. Significant ISP activity in retarding ice crystal growth was observed in all solutions (44% for the most complex mix) containing 0.13% total protein from AWWE. In heat-shocked ice cream, ice recrystallization rates were significantly reduced 40 and 46% with the addition of 0.0025 and 0.0037% total protein from AWWE. The ISP activity in ice cream was not hindered by its inclusion in mix prior to pasteurization. A synergistic effect between ISP and stabilizer was observed, as ISP activity was reduced in the absence of stabilizer in ice cream formulations. A remarkably smoother texture for ice creams containing ISP after heat-shock storage was evident by sensory evaluation. The efficiency of ISP from AWWE in controlling ice crystal growth in ice cream has been demonstrated.

  9. Mass balance and surface movement of the Greenland Ice Sheet at Summit, Central Greenland

    DEFF Research Database (Denmark)

    Hvidberg, C.S.; Keller, K.; Gundestrup, N.S.


    During the GRIP deep drilling in Central Greenland, the ice sheet topography and surface movement at Summit has been mapped with GPS. Measurements of the surface velocity are presented for a strain net consisting of 13 poles at distances of 25-60 km from the GRIP site. Some results are: The GRIP...... site is located approximately 2 km NW of the topographic summit; the surface velocity at the GISP 2 site is 1.7 m/yr in the W direction. The present mass balance at Summit is calculated to be -0.03+/-0.04 m/yr, i.e. close to steady state. This result is the best now available for Summit. A small...... thinning rate might be a transient response of the Greenland Ice Sheet due to the temperature increase at the Wisconsin-Holocene transition....

  10. The effect of signal leakage and glacial isostatic rebound on GRACE-derived ice mass changes in Iceland (United States)

    Sørensen, Louise Sandberg; Jarosch, Alexander H.; Aðalgeirsdóttir, Guðfinna; Barletta, Valentina R.; Forsberg, René; Pálsson, Finnur; Björnsson, Helgi; Jóhannesson, Tómas


    Monthly gravity field models from the GRACE satellite mission are widely used to determine ice mass changes of large ice sheets as well as smaller glaciers and ice caps. Here, we investigate in detail the ice mass changes of the Icelandic ice caps as derived from GRACE data. The small size of the Icelandic ice caps, their location close to other rapidly changing ice covered areas and the low viscosity of the mantle below Iceland make this especially challenging. The mass balance of the ice caps is well constrained by field mass balance measurements, making this area ideal for such investigations. We find that the ice mass changes of the Icelandic ice caps derived from GRACE gravity field models are influenced by both the large gravity change signal resulting from ice mass loss in southeast Greenland and the mass redistribution within the Earth mantle due to glacial isostatic adjustment since the Little Ice Age (∼1890 AD). To minimize the signal that leaks towards Iceland from Greenland, we employ an independent mass change estimate of the Greenland Ice Sheet derived from satellite laser altimetry. We also estimate the effect of post Little Ice Age glacial isostatic adjustment, from knowledge of the ice history and GPS network constrained crustal deformation data. We find that both the leakage from Greenland and the post Little Ice Age glacial isostatic adjustment are important to take into account, in order to correctly determine Iceland ice mass changes from GRACE, and when applying these an average mass balance of the Icelandic ice caps of -11.4 ± 2.2 Gt yr-1 for the period 2003-2010 is found. This number corresponds well with available mass balance measurements.

  11. University of Wisconsin Oshkosh Anaerobic Dry Digestion Facility

    Energy Technology Data Exchange (ETDEWEB)

    Koker, John [Univ. of Wisconsin, Oshkosh, WI (United States); Lizotte, Michael [Univ. of Wisconsin, Oshkosh, WI (United States)


    The University of Wisconsin Oshkosh Anaerobic Dry Digestion Facility is a demonstration project that supported the first commercial-scale use in the United States of high solids, static pile technology for anaerobic digestion of organic waste to generate biogas for use in generating electricity and heat. The research adds to the understanding of startup, operation and supply chain issues for anaerobic digester technology. Issues and performance were documented for equipment installation and modifications, feedstock availability and quality, weekly loading and unloading of digestion chambers, chemical composition of biogas produced, and energy production. This facility also demonstrated an urban industrial ecology approach to siting such facilities near sewage treatment plants (to capture and use excess biogas generated by the plants) and organic yard waste collection sites (a source of feedstock).

  12. The business of optimism. Wisconsin's Midwest Renewable Energy Fair

    International Nuclear Information System (INIS)

    Decker, J.


    The paper reports on the Wisconsin Midwest Renewable Energy Fair. The renewable energy business is said to be based on sound technology and sustainable development and is being largely embraced with enthusiasm. However, the keynote speaker, James Kunstler, warned that the transition from fossil fuels to renewables will be complicated and messy. The report mentions the views of several speakers but not all shared Kunstler's views. There were more than 100 workshops at the fair. Although big business was well represented, there were also home-made devices on show including a motorcycle powered by electricity. The importance of the fair is probably best judged by the way in which it generates enthusiasm for preserving the planet through the sustainable development of environmentally-friendly technology. (author)

  13. Process energy efficiency improvement in Wisconsin cheese plants

    International Nuclear Information System (INIS)

    Zehr, S.; Mitchell, J.; Reinemann, D.; Klein, S.; Reindl, D.


    Costs for the energy involved in cheese making has a major impact on profit. Although industrial cheese plants differ in size, production equipment, and the manner in which whey is processed, there are common elements in most plants. This paper evaluates several process integration opportunities at two representative cheese plants in Wisconsin. Pinch analysis is used to help assess the heat recovery potential for the major thermal processes in the plants. The potential of using packaged cheese as a thermal storage medium to allow electrical demand shifting in the cold storage warehouse is evaluated and shown to be feasible. Three major conservation measures are identified with a total cost savings of $130,000 to $160,000 annually

  14. Polar Stereographic Valid Ice Masks Derived from National Ice Center Monthly Sea Ice Climatologies, Version 1 (United States)

    National Aeronautics and Space Administration — These valid ice masks provide a way to remove spurious ice caused by residual weather effects and land spillover in passive microwave data. They are derived from the...

  15. Analysis on ice resistance and ice response of ships sailing in brash ice

    Directory of Open Access Journals (Sweden)

    WANG Chao


    Full Text Available [Objectives] In order to explore the interaction between a hull and crushed ice, [Methods] a discrete element model is combined with Euler multiphase flow. The force of a hull under different speeds and different ice levels is calculated, and the motion response of ice during ship-ice interaction discussed. The reasons for ice resistance and movement change are explained intuitively. [Results] The ice resistance of the hull is obtained, mainly due to the friction and collision of the crushed ice and hull surface, which increases with the increase of the speed, but when the speed increases to a certain value, the crushing resistance no longer increases and even reduces the trend. [Conclusions] This provides a reference for the optimization of ship type for ice zones, as well as propeller design.

  16. IceCube SWIRP (United States)

    Wu, Dongliang L.


    Clouds, ice clouds in particular, are a major source of uncertainty in climate models. Submm-wave sensors fill the sensitivity gap between MW and IR.Cloud microphysical properties (particle size and shape) account for large (200 and 40) measurement uncertainty.

  17. Ecology under lake ice

    NARCIS (Netherlands)

    Hampton, Stephanie E.; Galloway, Aaron W. E.; Powers, Stephen M.; Ozersky, Ted; Woo, Kara H.; Batt, Ryan D.; Labou, Stephanie G.; O'Reilly, Catherine M.; Sharma, Sapna; Lottig, Noah R.; Stanley, Emily H.; North, Rebecca L.; Stockwell, Jason D.; Adrian, Rita; Weyhenmeyer, Gesa A.; Arvola, Lauri; Baulch, Helen M.; Bertani, Isabella; Bowman, Larry L., Jr.; Carey, Cayelan C.; Catalan, Jordi; Colom-Montero, William; Domine, Leah M.; Felip, Marisol; Granados, Ignacio; Gries, Corinna; Grossart, Hans-Peter; Haberman, Juta; Haldna, Marina; Hayden, Brian; Higgins, Scott N.; Jolley, Jeff C.; Kahilainen, Kimmo K.; Kaup, Enn; Kehoe, Michael J.; MacIntyre, Sally; Mackay, Anson W.; Mariash, Heather L.; Mckay, Robert M.; Nixdorf, Brigitte; Noges, Peeter; Noges, Tiina; Palmer, Michelle; Pierson, Don C.; Post, David M.; Pruett, Matthew J.; Rautio, Milla; Read, Jordan S.; Roberts, Sarah L.; Ruecker, Jacqueline; Sadro, Steven; Silow, Eugene A.; Smith, Derek E.; Sterner, Robert W.; Swann, George E. A.; Timofeyev, Maxim A.; Toro, Manuel; Twiss, Michael R.; Vogt, Richard J.; Watson, Susan B.; Whiteford, Erika J.; Xenopoulos, Marguerite A.

    Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experi-ence periods of snow and ice cover. Relatively little is known of winter ecology in these systems,due to a historical research focus on summer ‘growing seasons’. We executed the first global

  18. User's guide for ICE

    International Nuclear Information System (INIS)

    Fraley, S.K.


    ICE is a cross-section mixing code which will accept cross sections from an AMPX working library and produce mixed cross sections in the AMPX working library format, ANISN format, and the group-independent ANISN format. User input is in the free-form or fixed-form FIDO structure. The code is operable as a module in the AMPX system

  19. Melting ice, growing trade?

    Directory of Open Access Journals (Sweden)

    Sami Bensassi


    Full Text Available Abstract Large reductions in Arctic sea ice, most notably in summer, coupled with growing interest in Arctic shipping and resource exploitation have renewed interest in the economic potential of the Northern Sea Route (NSR. Two key constraints on the future viability of the NSR pertain to bathymetry and the future evolution of the sea ice cover. Climate model projections of future sea ice conditions throughout the rest of the century suggest that even under the most “aggressive” emission scenario, increases in international trade between Europe and Asia will be very low. The large inter-annual variability of weather and sea ice conditions in the route, the Russian toll imposed for transiting the NSR, together with high insurance costs and scarce loading/unloading opportunities, limit the use of the NSR. We show that even if these obstacles are removed, the duration of the opening of the NSR over the course of the century is not long enough to offer a consequent boost to international trade at the macroeconomic level.

  20. Glacial-interglacial sea ice proxies from the Antarctic Peninsula using the James Ross Island ice core. (United States)

    Benton, A. K.; Mulvaney, R.; Triest, J.; Abram, N.


    Ice core records from Antarctica have shown promise as highly-resolved indicators of regional sea ice change, but to date semi-quantified reconstructions do not extend back more than ~150 years. In this study the chemical composition of the James Ross Island ice core is presented as a potential sea ice proxy record spanning the full Holocene and into the last glacial interval. A CFA-TE method was used to analyse the chemical composition of the entire 363.9m core including final 5m which contains evidence of glacial age ice. MSA- and major anions were measured at 4cm effective resolution, along with trace elements Na, Ca, K, Mg, Mn, H2O2, NO3, total conductivity and dust at <0.5cm effective resolution. Seasonal signals from H2O2 in the upper 50m of the core support the use of non sea salt-SO42- for determining seasonality in deeper sections. This multi-proxy analysis of the oldest ice core to date from the Antarctic Peninsula region allows the concurrent interpretation of sea ice changes and their environmental drivers. The potential dual influence of previous winter sea ice extent and air pathway source region on MSA concentrations in the core are interpreted with use of Na as a winter maximum indicator and Ca and dust signal strength showing changes in dust flux indicating potential source region variation.

  1. Ice shelf fracture parameterization in an ice sheet model

    Directory of Open Access Journals (Sweden)

    S. Sun


    Full Text Available Floating ice shelves exert a stabilizing force onto the inland ice sheet. However, this buttressing effect is diminished by the fracture process, which on large scales effectively softens the ice, accelerating its flow, increasing calving, and potentially leading to ice shelf breakup. We add a continuum damage model (CDM to the BISICLES ice sheet model, which is intended to model the localized opening of crevasses under stress, the transport of those crevasses through the ice sheet, and the coupling between crevasse depth and the ice flow field and to carry out idealized numerical experiments examining the broad impact on large-scale ice sheet and shelf dynamics. In each case we see a complex pattern of damage evolve over time, with an eventual loss of buttressing approximately equivalent to halving the thickness of the ice shelf. We find that it is possible to achieve a similar ice flow pattern using a simple rule of thumb: introducing an enhancement factor ∼ 10 everywhere in the model domain. However, spatially varying damage (or equivalently, enhancement factor fields set at the start of prognostic calculations to match velocity observations, as is widely done in ice sheet simulations, ought to evolve in time, or grounding line retreat can be slowed by an order of magnitude.

  2. Autonomous Ice Mass Balance Buoys for Seasonal Sea Ice (United States)

    Whitlock, J. D.; Planck, C.; Perovich, D. K.; Parno, J. T.; Elder, B. C.; Richter-Menge, J.; Polashenski, C. M.


    The ice mass-balance represents the integration of all surface and ocean heat fluxes and attributing the impact of these forcing fluxes on the ice cover can be accomplished by increasing temporal and spatial measurements. Mass balance information can be used to understand the ongoing changes in the Arctic sea ice cover and to improve predictions of future ice conditions. Thinner seasonal ice in the Arctic necessitates the deployment of Autonomous Ice Mass Balance buoys (IMB's) capable of long-term, in situ data collection in both ice and open ocean. Seasonal IMB's (SIMB's) are free floating IMB's that allow data collection in thick ice, thin ice, during times of transition, and even open water. The newest generation of SIMB aims to increase the number of reliable IMB's in the Arctic by leveraging inexpensive commercial-grade instrumentation when combined with specially developed monitoring hardware. Monitoring tasks are handled by a custom, expandable data logger that provides low-cost flexibility for integrating a large range of instrumentation. The SIMB features ultrasonic sensors for direct measurement of both snow depth and ice thickness and a digital temperature chain (DTC) for temperature measurements every 2cm through both snow and ice. Air temperature and pressure, along with GPS data complete the Arctic picture. Additionally, the new SIMB is more compact to maximize deployment opportunities from multiple types of platforms.

  3. Survival rates and lifetime reproduction of breeding male Cooper’s Hawks in Wisconsin, 1980-2005 (United States)

    Rosenfield, Robert N.; Bielefeldt, John; Rosenfield, Laura J.; Booms, Travis L.; Bozek, Michael A.


    There are few published data on annual survival and no reports of lifetime reproduction for breeding Cooper's Hawks (Accipiter cooperii). Breeding males (n  =  105) in central and southeastern Wisconsin had an annual mortality rate of 19%, or a survival rate of 81% for birds ≤10 years of age. We did not detect significant differences in mortality rates between urban and rural habitats, nor between the earlier 13 years and later 13 years of this study. Male Cooper's Hawks produced from zero to 32 nestlings during their lifetimes. Body mass or size appeared unrelated to annual survivorship and lifetime reproduction, although lifetime reproduction was correlated strongly with longevity of breeding males. Fifteen of 66 males (23%) produced most (53%) of the nestlings. Our studies occurred in an area where breeding populations may be increasing with some of the highest reported productivity indices and nesting densities for this species. Habitat used for nesting on our Wisconsin study areas may be less important for survivorship and lifetime reproduction than acquisition of a nesting area in which a male will breed throughout his life.

  4. Ice particle collisions (United States)

    Sampara, Naresh; Turnbull, Barbara; Hill, Richard; Swift, Michael


    Granular interactions of ice occur in a range of geophysical, astrophysical and industrial applications. For example, Saturn's Rings are composed of icy particles from micrometers to kilometres in size - inertial and yet too small to interact gravitationally. In clouds, ice crystals are smashed to pieces before they re-aggregate to for snow floccules in a process that is very much open to interpretation. In a granular flow of ice particles, the energy spent in collisions can lead to localized surface changes and wetting, which in turn can promote aggregation. To understand the induced wetting and its effects, we present two novel experimental methods which provide snippets of insight into the collisional behaviour of macroscopic ice particles. Experiment 1: Microgravity experiments provide minute details of the contact between the ice particles during the collision. A diamagnetic levitation technique, as alternative to the parabolic flight or falling tower experiments, was used to understand the collisional behaviour of individual macroscopic icy bodies. A refrigerated cylinder, that can control ambient conditions, was inserted into the bore of an 18 Tesla superconducting magnet and cooled to -10°C. Initial binary collisions were created, where one 4 mm ice particle was levitated in the magnet bore whilst another particle was dropped vertically from the top of the bore. The trajectories of both particles were captured by high speed video to provide the three-dimensional particle velocities and track the collision outcome. Introducing complexity, multiple particles were levitated in the bore and an azimuthal turbulent air flow introduced, allowing the particles to collide with other particles within a coherent fluid structure (mimicking Saturn's rings, or an eddy in a cloud). In these experiments, a sequence of collisions occur, each one different to the previous one due to the changes in surface characteristics created by the collisions themselves. Aggregation

  5. Icing Research Tunnel (United States)

    Chennault, Jonathan


    The Icing Research Tunnel in Building 11 at the NASA Glenn Research Center is committed to researching the effects of in flight icing on aircraft and testing ways to stop the formation of hazardous icing conditions on planes. During this summer, I worked here with Richard DelRosa, the lead engineer for this area. address one of the major concerns of aviation: icing conditions. During the war, many planes crashed (especially supply planes going over the.Himalayas) because ice built up in their wings and clogged the engines. To this day, it remains the largest ice tunnel in the world, with a test section that measures 6 feet high, 9 feet long, and 20 feet wide. It can simulate airspeeds from 50 to 300 miles per hour at temperatures as low as -50 Fahrenheit. Using these capabilities, IRT can simulate actual conditions at high altitudes. The first thing I did was creating a cross reference in Microsoft Excel. It lists commands for the DPU units that control the pressure and temperature variations in the tunnel, as well as the type of command (keyboard, multiplier, divide, etc). The cross reference also contains the algorithm for every command, and which page it is listed in on the control sheet (visual Auto-CAD graphs, which I helped to make). I actually spent most of the time on the computer using Auto-CAD. I drew a diagram of the entire icing tunnel and then drew diagrams of its various parts. Between my mentor and me, we have drawings of every part of it, from the spray bars to the thermocouples, power cabinets, input-output connectors for power systems, and layouts of various other machines. I was also responsible for drawing schematics for the Escort system (which controls the spray bars), the power system, DPUs, and other electrical systems. In my spare time, I am attempting to build and program the "toddler". Toddler is a walking robot that I have to program in PBASIC language. When complete, it should be able to walk on level terrain while avoiding obstacles in

  6. Improved ice loss estimate of the northwestern Greenland ice sheet

    DEFF Research Database (Denmark)

    Kjeldsen, Kristian Kjellerup; Khan, Shfaqat Abbas; Wahr, J.


    We estimate ice volume change rates in the northwest Greenland drainage basin during 2003–2009 using Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data. Elevation changes are often reported to be largest near the frontal portion of outlet glaciers. To improve the volume change...... a significant acceleration in mass loss at elevations above 1200 m. Both the improved mass loss estimate along the ice sheet margin and the acceleration at higher elevations have implications for predictions of the elastic adjustment of the lithosphere caused by present-day ice mass changes. Our study shows...... change. Our results show that adding Airborne Topographic Mapper and Land, Vegetation and Ice Sensor data to the ICESat data increases the catchment-wide estimate of ice volume loss by 11%, mainly due to an improved volume loss estimate along the ice sheet margin. Furthermore, our results show...

  7. Reliability of a Novel Social Activity Questionnaire: Perceived Social Support and Verbal Interaction in the Wisconsin Registry for Alzheimer's Prevention. (United States)

    Zuelsdorff, Megan L; Koscik, Rebecca L; Okonkwo, Ozioma C; Peppard, Paul E; Hermann, Bruce P; Sager, Mark A; Johnson, Sterling C; Engelman, Corinne D


    Social activity is associated with healthy aging and preserved cognition. Such activity includes a confluence of social support and verbal interaction, each influencing cognition through rarely parsed, mechanistically distinct pathways. We created a novel verbal interaction measure for the Wisconsin Registry for Alzheimer's Prevention (WRAP) and assessed reliability of resultant data, a first step toward mechanism-driven examination of social activity as a modifiable predictor of cognitive health. Two WRAP subsamples completed a test-retest study to determine 8-week stability ( n = 107) and 2-year stability ( n = 136) of verbal interaction, and 2-year stability of perceived social support. Reliability was determined using quadratic-weighted kappa, percent agreement, or correlation coefficients. Reliability was fair to almost perfect. The association between social support and interaction quantity decreased with age. Social activity data demonstrate moderate to excellent temporal stability. Moreover, in older individuals, social support and verbal interaction represent two distinct dimensions of social activity.

  8. IceCube: Particle Astrophysics with High Energy Neutrinos

    CERN Multimedia

    Université de Genève


    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Monday 7 May 2012 17h. - Ecole de Physique, Auditoire Stueckelberg IceCube: Particle Astrophysics with High Energy Neutrinos Prof. Francis Halzen / University of Wisconsin, Madison Construction and commissioning of the cubic-kilometer IceCube neutrino detector and its low energy extension DeepCore have been completed. The instrument detects neutrinos over a wide energy range: from 10 GeV atmospheric neutrinos to 1010 GeV cosmogenic neutrinos. We will discuss initial results based on a subsample of the ~100,000 neutrino events recorded during construction. We will emphasize the first measurement of the high-energy atmospheric neutrino spectrum, the search for the still enigmatic sources of the Galactic and extragalactic cosmic rays and for the particle nature of dark matter. Une ve...

  9. Ice Caps and Ice Belts: The Effects of Obliquity on Ice-Albedo Feedback (United States)

    Rose, Brian E. J.; Cronin, Timothy W.; Bitz, Cecilia M.


    Planetary obliquity determines the meridional distribution of the annual mean insolation. For obliquity exceeding 55°, the weakest insolation occurs at the equator. Stable partial snow and ice cover on such a planet would be in the form of a belt about the equator rather than polar caps. An analytical model of planetary climate is used to investigate the stability of ice caps and ice belts over the widest possible range of parameters. The model is a non-dimensional diffusive Energy Balance Model, representing insolation, heat transport, and ice-albedo feedback on a spherical planet. A complete analytical solution for any obliquity is given and validated against numerical solutions of a seasonal model in the “deep-water” regime of weak seasonal ice line migration. Multiple equilibria and unstable transitions between climate states (ice-free, Snowball, or ice cap/belt) are found over wide swaths of parameter space, including a “Large Ice-Belt Instability” and “Small Ice-Belt Instability” at high obliquity. The Snowball catastrophe is avoided at weak radiative forcing in two different scenarios: weak albedo feedback and inefficient heat transport (favoring stable partial ice cover), or efficient transport at high obliquity (favoring ice-free conditions). From speculative assumptions about distributions of planetary parameters, three-fourths to four-fifths of all planets with stable partial ice cover should be in the form of Earth-like polar caps.

  10. The Influence of Platelet Ice and Snow on Antarctic Land-fast Sea Ice


    Hoppmann, Mario; Nicolaus, Marcel


    Sea ice fastened to coasts, icebergs and ice shelves is of crucial importance for climate- and ecosystems. Near Antarctic ice shelves, this land-fast sea ice exhibits two unique characteristics that distinguish it from most other sea ice: 1) Ice platelets form and grow in super-cooled water, which originates from ice shelf cavities. The crystals accumulate beneath the solid sea-ice cover and are incorporated into the sea-ice fabric, contributing between 10 and 60% to the mas...

  11. Effect of Salted Ice Bags on Surface and Intramuscular Tissue Cooling and Rewarming Rates. (United States)

    Hunter, Eric J; Ostrowski, Jennifer; Donahue, Matthew; Crowley, Caitlyn; Herzog, Valerie


    Many researchers have investigated the effectiveness of different cryotherapy agents at decreasing intramuscular tissue temperatures. However, no one has looked at the effectiveness of adding salt to an ice bag. To compare the cooling effectiveness of different ice bags (wetted, salted cubed, and salted crushed) on cutaneous and intramuscular temperatures. Repeated-measures counterbalanced design. University research laboratory. 24 healthy participants (13 men, 11 women; age 22.46 ± 2.33 y, height 173.25 ± 9.78 cm, mass 74.51 ± 17.32 kg, subcutaneous thickness 0.63 ± 0.27 cm) with no lower-leg injuries, vascular diseases, sensitivity to cold, compromised circulation, or chronic use of NSAIDs. Ice bags made of wetted ice (2000 mL ice and 300 mL water), salted cubed ice (intervention A; 2000 mL of cubed ice and 1/2 tablespoon of salt), and salted crushed ice (intervention B; 2000 mL of crushed ice and 1/2 tablespoon of salt) were applied to the posterior gastrocnemius for 30 min. Each participant received all conditions with at least 4 d between treatments. Cutaneous and intramuscular (2 cm plus adipose thickness) temperatures of nondominant gastrocnemius were measured during a 10-min baseline period, a 30-min treatment period, and a 45-min rewarming period. Differences from baseline were observed for all treatments. The wetted-ice and salted-cubed-ice bags produced significantly lower intramuscular temperatures than the salted-crushed-ice bag. Wetted-ice bags produced the greatest temperature change for cutaneous tissues. Wetted- and salted-cubed-ice bags were equally effective at decreasing intramuscular temperature at 2 cm subadipose. Clinical practicality may favor salted-ice bags over wetted-ice bags.

  12. Analysis of sea ice dynamics (United States)

    Zwally, J.


    The ongoing work has established the basis for using multiyear sea ice concentrations from SMMR passive microwave for studies of largescale advection and convergence/divergence of the Arctic sea ice pack. Comparisons were made with numerical model simulations and buoy data showing qualitative agreement on daily to interannual time scales. Analysis of the 7-year SMMR data set shows significant interannual variations in the total area of multiyear ice. The scientific objective is to investigate the dynamics, mass balance, and interannual variability of the Arctic sea ice pack. The research emphasizes the direct application of sea ice parameters derived from passive microwave data (SMMR and SSMI) and collaborative studies using a sea ice dynamics model. The possible causes of observed interannual variations in the multiyear ice area are being examined. The relative effects of variations in the large scale advection and convergence/divergence within the ice pack on a regional and seasonal basis are investigated. The effects of anomolous atmospheric forcings are being examined, including the long-lived effects of synoptic events and monthly variations in the mean geostrophic winds. Estimates to be made will include the amount of new ice production within the ice pack during winter and the amount of ice exported from the pack.

  13. Social Vulnerability Index (SoVI) for Wisconsin based on 2000 Census Block Groups (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data depicts the social vulnerability of Wisconsin census block groups to environmental hazards. Data were culled primarily from the 2000 Decennial Census.

  14. Phosphorus Loading and Compositional Characteristics in Eight-Mile Run Watershed, Wisconsin

    National Research Council Canada - National Science Library

    James, William


    The purpose of this research was to describe and quantify biologically labile and refractory phosphorus runoff in Eight-Mile Run, a small watershed in west-central Wisconsin that is impacted by dairy...

  15. Phosphorus Equilibrium Characteristics for Soils in the Upper Eau Galle River Watershed, Wisconsin

    National Research Council Canada - National Science Library

    James, William F


    The purpose of this demonstration was to examine phosphorus adsorption-desorption and equilibrium characteristics for soils collected from different land use practices in the Upper Eau Galle River watershed (Wisconsin...

  16. Wisconsin State Briefing Book for low-level radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)


    The Wisconsin State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Wisconsin. The profile is the result of a survey of NRC licensees in Wisconsin. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Wisconsin.

  17. Evaluation of wood species and preservatives for Wisconsin transportation sign posts : [research brief]. (United States)


    The Wisconsin Department of Transportation (WisDOT) administers approximately 11,800 miles of state highways. It uses preservative-treated wood posts for much of the signage along these highways because wood is relatively inexpensive, easy to install...

  18. Determination of resilient modulus values for typical plastic soils in Wisconsin. (United States)


    "The objectives of this research are to establish a resilient modulus test results database and to develop : correlations for estimating the resilient modulus of Wisconsin fine-grained soils from basic soil properties. A : laboratory testing program ...

  19. Wisconsin State Briefing Book for low-level radioactive waste management

    International Nuclear Information System (INIS)


    The Wisconsin State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Wisconsin. The profile is the result of a survey of NRC licensees in Wisconsin. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Wisconsin

  20. 77 FR 48538 - Notice of Inventory Completion: State Historical Society of Wisconsin, Madison, WI (United States)


    ... Historical Society of Wisconsin at the address below by September 13, 2012. ADDRESSES: Jennifer Kolb... Indian tribe that believes it satisfies the criteria in 43 CFR 10.11(c)(1) should contact Jennifer Kolb...

  1. Evidence of past climate change in the Little Ice Age and of the Pacific Decadal Oscillation periodicity in Africa: comparison between two neighbor stalagmites from Namibia and Botswana (preliminary results) (United States)

    Voarintsoa, N. G.; Railsback, L. B.; Liang, F.; Brook, G. A.; Cheng, H.; Edwards, R.


    , when abrupt wet seasons follow drier ones every 30 to 40 years. We propose this cycle would match with the Pacific Decadal Oscillation, a pattern of change (warm or cool surface waters) in the Pacific Ocean's climate that occurs every 20 to 30 years. Furthermore, a major climatic shift around the 1600s is also apparent, when both δ18O and δ13C in the Dante Cave stalagmite decrease by ~ 3-4 ‰, indicating a dramatic change from dry to wet conditions. This change is followed by a shift to a drier climate from 1650 to 1950 for both DP1 and BC97-94. The abrupt change in isotopic data is coeval with the transition from the Medieval Climate Anomaly (prior to AD 1600) to the Little Ice Age (~AD 1350-1850), and possibly the onset of the Maunder Sunspot Minimum (1645-1715). The stalagmite data show that major Late Holocene climate events recorded in the Northern Hemisphere also impacted the Southern Hemisphere, including Southern Africa. The rapid changes in isotopic values are also mirrored by changes in stalagmite petrography. Crystals of calcite with a distinctly brownish/yellowish color in DP1 samples reflect the wet period in Namibia, and a Type E (erosional) layer-bounding surface in BC97-14 marks the onset of the very wet period in Botswana.

  2. Climatic implications of glacial evolution in the Tröllaskagi peninsula (northern Iceland) since the Little Ice Age maximum. The cases of the Gljúfurárjökull and Tungnahryggsjökull glaciers (United States)

    Fernández-Fernández, José M.; Andrés, Nuria; Brynjólfsson, Skafti; Sæmundsson, Þorsteinn; Palacios, David


    The Tröllaskagi peninsula is located in northern Iceland, between meridians 19°30'W and 18°10'W, jutting out into the North Atlantic to latitude 66°12'N and joining the central highlands to the south. About 150 glaciers located on the Tröllaskagi peninsula reached their Holocene maximum extent during the Little Ice Age (LIA) maximum at the end of the 19th century. The sudden warming at the turn of the 20th century triggered a continuous retreat from the LIA maximum positions, interrupted by a reversal trend during the mid-seventies and eighties in response to a brief period of climate cooling. The aim of this paper is to analyze the relationships between glacial and climatic evolution since the LIA maximum. For this reason, we selected three small debris-free glaciers: Gljúfurárjökull, and western and eastern Tungnahryggsjökull, at the headwalls of Skíðadalur and Kolbeinsdalur, as their absence of debris cover makes them sensitive to climatic fluctuations. To achieve this purpose, we used ArcGIS to map the glacier extent during the LIA maximum and several dates over four georeferenced aerial photos (1946, 1985, 1994 and 2000), as well as a 2005 SPOT satellite image. Then, the Equilibrium-Line Altitude (ELA) was calculated by applying the Accumulation Area Ratio (AAR) and Area Altitude Balance Ratio (AABR) approaches. Climatological data series from the nearby weather stations were used in order to analyze climate development and to estimate precipitation at the ELA with different numerical models. Our results show considerable changes of the three debris-free glaciers and demonstrates their sensitivity to climatic fluctuations. As a result of the abrupt climatic transition of the 20th century, the following warm 25-year period and the warming started in the late eighties, the three glaciers retreated by ca. 990-1330 m from the LIA maximum to 2005, supported by a 40-metre ELA rise and a reduction of their area and volume of 25% and 33% on average

  3. Towards multi-decadal to multi-millennial ice core records from coastal west Greenland ice caps (United States)

    Das, Sarah B.; Osman, Matthew B.; Trusel, Luke D.; McConnell, Joseph R.; Smith, Ben E.; Evans, Matthew J.; Frey, Karen E.; Arienzo, Monica; Chellman, Nathan


    The Arctic region, and Greenland in particular, is undergoing dramatic change as characterized by atmospheric warming, decreasing sea ice, shifting ocean circulation patterns, and rapid ice sheet mass loss, but longer records are needed to put these changes into context. Ice core records from the Greenland ice sheet have yielded invaluable insight into past climate change both regionally and globally, and provided important constraints on past surface mass balance more directly, but these ice cores are most often from the interior ice sheet accumulation zone, at high altitude and hundreds of kilometers from the coast. Coastal ice caps, situated around the margins of Greenland, have the potential to provide novel high-resolution records of local and regional maritime climate and sea surface conditions, as well as contemporaneous glaciological changes (such as accumulation and surface melt history). But obtaining these records is extremely challenging. Most of these ice caps are unexplored, and thus their thickness, age, stratigraphy, and utility as sites of new and unique paleoclimate records is largely unknown. Access is severely limited due to their high altitude, steep relief, small surface area, and inclement weather. Furthermore, their relatively low elevation and marine moderated climate can contribute to significant surface melting and degradation of the ice stratigraphy. We recently targeted areas near the Disko Bay region of central west Greenland where maritime ice caps are prevalent but unsampled, as potential sites for new multi-decadal to multi-millennial ice core records. In 2014 & 2015 we identified two promising ice caps, one on Disko Island (1250 m. asl) and one on Nuussuaq Peninsula (1980 m. asl) based on airborne and ground-based geophysical observations and physical and glaciochemical stratigraphy from shallow firn cores. In spring 2015 we collected ice cores at both sites using the Badger-Eclipse electromechanical drill, transported by a medley

  4. The evolution of Wisconsin's urban FIA program—yesterday today and tomorrow (United States)

    Andrew M. Stoltman; Richard B. Rideout


    In 2002, Wisconsin was part of two pilot projects in cooperation with the US Forest Service. The first was a street tree assessment, and the second was an urban FIA project. The data generated by these pilots changed the way that Wisconsin DNRs’ Urban Forestry Program conducts its business. Although there have been several urban FIA pilot projects throughout the U.S.,...

  5. Heterogeneous nucleation of ice on model carbon surfaces (United States)

    Molinero, V.; Lupi, L.; Hudait, A.


    Carbonaceous particles account for 10% of the particulate matter in the atmosphere. The experimental investigation of heterogeneous freezing of water droplets by carbonaceous particles reveals widespread ice freezing temperatures. The origin of the soot and its oxidation and aging modulate its ice nucleation ability, however, it is not known which structural and chemical characteristics of soot account for the variability in ice nucleation efficiency. We find that atomically flat carbon surfaces promote heterogeneous nucleation of ice, while molecularly rough surfaces with the same hydrophobicity do not. We investigate a large set of graphitic surfaces of various dimensions and radii of curvature consistent with those of soot in experiments, and find that variations in nanostructures alone could account for the spread in the freezing temperatures of ice on soot in experiments. A characterization of the nanostructure of soot is needed to predict its ice nucleation efficiency. Atmospheric oxidation and aging of soot modulates its ice nucleation ability. It has been suggested that an increase in the ice nucleation ability of aged soot results from an increase in the hydrophilicity of the surfaces upon oxidation. Oxidation, however, also impacts the nanostructure of soot, making it difficult to assess the separate effects of soot nanostructure and hydrophilicity in experiments. We investigate the effect of changes in hydrophilicity of model graphitic surfaces on the freezing temperature of ice. Our results indicate that the hydrophilicity of the surface is not in general a good predictor of ice nucleation ability. We find a correlation between the ability of a surface to promote nucleation of ice and the layering of liquid water at the surface. The results of this work suggest that ordering of liquid water in contact with the surface plays an important role in the heterogeneous ice nucleation mechanism. References: L. Lupi, A. Hudait and V. Molinero, J. Am. Chem. Soc

  6. Simulation of groundwater flow in the glacial aquifer system of northeastern Wisconsin with variable model complexity (United States)

    Juckem, Paul F.; Clark, Brian R.; Feinstein, Daniel T.


    The U.S. Geological Survey, National Water-Quality Assessment seeks to map estimated intrinsic susceptibility of the glacial aquifer system of the conterminous United States. Improved understanding of the hydrogeologic characteristics that explain spatial patterns of intrinsic susceptibility, commonly inferred from estimates of groundwater age distributions, is sought so that methods used for the estimation process are properly equipped. An important step beyond identifying relevant hydrogeologic datasets, such as glacial geology maps, is to evaluate how incorporation of these resources into process-based models using differing levels of detail could affect resulting simulations of groundwater age distributions and, thus, estimates of intrinsic susceptibility.This report describes the construction and calibration of three groundwater-flow models of northeastern Wisconsin that were developed with differing levels of complexity to provide a framework for subsequent evaluations of the effects of process-based model complexity on estimations of groundwater age distributions for withdrawal wells and streams. Preliminary assessments, which focused on the effects of model complexity on simulated water levels and base flows in the glacial aquifer system, illustrate that simulation of vertical gradients using multiple model layers improves simulated heads more in low-permeability units than in high-permeability units. Moreover, simulation of heterogeneous hydraulic conductivity fields in coarse-grained and some fine-grained glacial materials produced a larger improvement in simulated water levels in the glacial aquifer system compared with simulation of uniform hydraulic conductivity within zones. The relation between base flows and model complexity was less clear; however, the relation generally seemed to follow a similar pattern as water levels. Although increased model complexity resulted in improved calibrations, future application of the models using simulated particle

  7. Deep Radiostratigraphy of the East Antarctic Plateau: Connecting the Dome C and Vostok Ice Core Sites (United States)

    Cavitte, Marie G. P.; Blankenship, Donald D.; Young, Duncan A.; Schroeder, Dustin M.; Parrenin, Frederic; Lemeur, Emmanuel; Macgregor, Joseph A.; Siegert, Martin J.


    Several airborne radar-sounding surveys are used to trace internal reflections around the European Project for Ice Coring in Antarctica Dome C and Vostok ice core sites. Thirteen reflections, spanning the last two glacial cycles, are traced within 200 km of Dome C, a promising region for million-year-old ice, using the University of Texas Institute for Geophysics High-Capacity Radar Sounder. This provides a dated stratigraphy to 2318 m depth at Dome C. Reflection age uncertainties are calculated from the radar range precision and signal-to-noise ratio of the internal reflections. The radar stratigraphy matches well with the Multichannel Coherent Radar Depth Sounder (MCoRDS) radar stratigraphy obtained independently. We show that radar sounding enables the extension of ice core ages through the ice sheet with an additional radar-related age uncertainty of approximately 1/3-1/2 that of the ice cores. Reflections are extended along the Byrd-Totten Glacier divide, using University of Texas/Technical University of Denmark and MCoRDS surveys. However, core-to-core connection is impeded by pervasive aeolian terranes, and Lake Vostok's influence on reflection geometry. Poor radar connection of the two ice cores is attributed to these effects and suboptimal survey design in affected areas. We demonstrate that, while ice sheet internal radar reflections are generally isochronal and can be mapped over large distances, careful survey planning is necessary to extend ice core chronologies to distant regions of the East Antarctic ice sheet.

  8. Incidence of Concussion in Youth Ice Hockey Players. (United States)

    Kontos, Anthony P; Elbin, R J; Sufrinko, Alicia; Dakan, Scott; Bookwalter, Kylie; Price, Ali; Meehan, William P; Collins, Michael W


    Ice hockey is a fast-paced collision sport that entails both intentional (ie, body checking) and incidental contact that may involve the head. The objective of this study was to determine the incidence of concussions in relation to games/practices and age among competition-level youth ice hockey players (ages 12-18 years). Participants included 397 youth ice hockey players from Western Pennsylvania; Boston, Massachusetts; and Birmingham, Alabama, during the 2012-2013 and 2013-2014 youth ice hockey seasons. Incidence rates (IRs) and incidence rate ratios (IRRs) of concussion were calculated for games/practices and age groups. A total of 23 369 (12 784 practice/10 585 game) athletic exposures (AEs) involving 37 medically diagnosed concussions occurred. More than 40% of concussions involved illegal contact. The combined IR for games and practices was 1.58 concussions per 1000 AEs. The IRR was 2.86 times (95% confidence interval 0.68-4.42) higher during games (2.49 per 1000 AEs) than practices (1.04 per 1000 AEs). The overall IR for concussion in youth ice hockey was comparable to those reported in other youth collision sports. The game-to-practice IRR was lower than previously reported in ice hockey and other youth sports, although more concussions per exposure occurred in games compared with practices. Younger players had a higher rate of concussions than older players. Copyright © 2016 by the American Academy of Pediatrics.

  9. Incidence of Concussion in Youth Ice Hockey Players (United States)

    Elbin, R.J.; Sufrinko, Alicia; Dakan, Scott; Bookwalter, Kylie; Price, Ali; Meehan, William P.; Collins, Michael W.


    BACKGROUND: Ice hockey is a fast-paced collision sport that entails both intentional (ie, body checking) and incidental contact that may involve the head. The objective of this study was to determine the incidence of concussions in relation to games/practices and age among competition-level youth ice hockey players (ages 12–18 years). METHODS: Participants included 397 youth ice hockey players from Western Pennsylvania; Boston, Massachusetts; and Birmingham, Alabama, during the 2012–2013 and 2013–2014 youth ice hockey seasons. Incidence rates (IRs) and incidence rate ratios (IRRs) of concussion were calculated for games/practices and age groups. RESULTS: A total of 23 369 (12 784 practice/10 585 game) athletic exposures (AEs) involving 37 medically diagnosed concussions occurred. More than 40% of concussions involved illegal contact. The combined IR for games and practices was 1.58 concussions per 1000 AEs. The IRR was 2.86 times (95% confidence interval 0.68–4.42) higher during games (2.49 per 1000 AEs) than practices (1.04 per 1000 AEs). CONCLUSIONS: The overall IR for concussion in youth ice hockey was comparable to those reported in other youth collision sports. The game-to-practice IRR was lower than previously reported in ice hockey and other youth sports, although more concussions per exposure occurred in games compared with practices. Younger players had a higher rate of concussions than older players. PMID:26746405

  10. Possible contribution of ice-sheet/lithosphere interactions to past glaciological changes in Greenland (United States)

    Alley, R. B.; Parizek, B. R.; Anandakrishnan, S.; Pollard, D.; Stevens, N. T.; Pourpoint, M.


    Ice-lithosphere interactions may have influenced the history of ice-sheet sensitivity to climate change. The Greenland ice sheet (GIS) is sensitive to warming, and is likely to be largely removed if subjected to relatively small additional temperature increases. The recent report (Schaefer et al., 2016, Nature) of near-complete GIS removal under modest Pleistocene forcing suggests that GIS sensitivity may be even greater than generally modeled, but lack of major Holocene retreat is more consistent with existing models. As shown by Stevens et al. (2016, JGR), peak lithospheric flexural stresses associated with ice-age GIS cycling are of the same order as dike-driving stresses in plutonic systems, and migrate over ice-age cycles. The full analysis by Stevens et al. suggests the possibility that the onset of cyclic ice-sheet loading allowed deep melt associated with the passage of the Icelandic hot spot beneath Greenland to work up though the crust to or near the base of the ice sheet, helping explain the anomalous geothermal heat fluxes observed at the head of the Northeast Greenland Ice Stream and elsewhere in the northern part of GIS. If ice-age cycling aided extraction of an existing reservoir of melted rock, then geothermal heat flux would have risen with the onset of extraction and migration, but with a subsequent fall associated with reservoir depletion. Simple parameterized flow-model simulations confirm intuition that a higher geothermal flux makes deglaciation easier, with the northern part of the ice sheet especially important. Large uncertainties remain in quantification, but we suggest the hypothesis that, following the onset of ice-age cycling, deglaciation of the GIS first became easier and then more difficult in response to feedbacks involving the ice sheet and the geological system beneath. In turn, this suggests that evidence of past deglaciation under moderate forcing is consistent with existing ice-sheet models.

  11. National survey of children with special health care needs: Wisconsin-specific data. (United States)

    Oftedahl, Elizabeth; Benedict, Ruth; Katcher, Murray L


    The National Center for Health Statistics developed and conducted (2000-2002) the National Survey of Children with Special Health Care Needs (CSHCN), a module of the State and Local Area Integrated Telephone Survey (SLAITS). The purpose of this paper is to present the Wisconsin-specific data derived from analysis of the national survey and to make a comparison with the United States as a whole. In Wisconsin, approximately one fifth (21%) of households have CSHCN, and 13.4% of children have a special health care need; US comparison data are 20% and 12.8%, respectively. When examined by type of special need, Wisconsin shows slightly higher proportions of CSHCN in all categories, when compared with U.S. data, with the exception of limitation in activity. Families in Wisconsin with CSHCN are more likely to report being involved with medical decision making and satisfied with services they receive (67%); having a medical home (57%); having adequate insurance; easy use of community-based service systems (81%); and receiving services to make transition to adult life (7.5%). Though Wisconsin has a slightly higher proportion of CSHCN than the United States as a whole, a greater proportion of Wisconsin families receive important services. These measurements allow us to strive for further improvement through coordination of services in the private health care delivery sector with public health programs.

  12. Experimental provocation of 'ice-cream headache' by ice cubes and ice water. (United States)

    Mages, Stephan; Hensel, Ole; Zierz, Antonia Maria; Kraya, Torsten; Zierz, Stephan


    Background There are various studies on experimentally provoked 'ice-cream headache' or 'headache attributed to ingestion or inhalation of a cold stimulus' (HICS) using different provocation protocols. The aim of this study was to compare two provocation protocols. Methods Ice cubes pressed to the palate and fast ingestion of ice water were used to provoke HICS and clinical features were compared. Results The ice-water stimulus provoked HICS significantly more often than the ice-cube stimulus (9/77 vs. 39/77). Ice-water-provoked HICS had a significantly shorter latency (median 15 s, range 4-97 s vs. median 68 s, range 27-96 s). There was no difference in pain localisation. Character after ice-cube stimulation was predominantly described as pressing and after ice-water stimulation as stabbing. A second HICS followed in 10/39 (26%) of the headaches provoked by ice water. Lacrimation occurred significantly more often in volunteers with than in those without HICS. Discussion HICS provoked by ice water was more frequent, had a shorter latency, different pain character and higher pain intensity than HICS provoked by ice cubes. The finding of two subsequent HICS attacks in the same volunteers supports the notion that two types of HICS exist. Lacrimation during HICS indicates involvement of the trigeminal-autonomic reflex.

  13. Production and characterization of ice cream with high content in oleic and linoleic fatty acids

    DEFF Research Database (Denmark)

    Marín-Suárez, Marta; García Moreno, Pedro Jesús; Padial-Domínguez, Marta


    Ice creams produced with unsaturated fats rich in oleic (OO, 70.7% of oleic) and linoleic (LO, 49.0% of linoleic) fatty acids, were compared to ice cream based on saturated coconut oil (CO, 50% of lauric acid). The globule size distribution of OO mix during aging (72 h at 4°C) followed a similar...... trend to CO mix, being stable after 48 h; whereas LO mix destabilized after 24 h. CO mix showed higher destabilization during ice cream production, but no significant differences among fats were observed in the particle size of the ice cream produced. The overrun was also lower for OO and LO ice creams...... (34.19 and 27.12%, respectively) compared to CO based ice cream (45.06%). However, an improved melting behavior, which gradually decreased from 88.69% for CO to 66.09% for LO ice cream, was observed....

  14. Animals and ICE

    DEFF Research Database (Denmark)

    van Hemmen, J Leo; Christensen-Dalsgaard, Jakob; Carr, Catherine E


    experimental and mathematical foundation, it is known that there is a low-frequency regime where the internal time difference (iTD) as perceived by the animal may well be 2-5 times higher than the external ITD, the interaural time difference, and that there is a frequency plateau over which the fraction i......TD/ITD is constant. There is also a high-frequency regime where the internal level (amplitude) difference iLD as perceived by the animal is much higher than the interaural level difference ILD measured externally between the two ears. The fundamental tympanic frequency segregates the two regimes. The present special...... issue devoted to "internally coupled ears" provides an overview of many aspects of ICE, be they acoustic, anatomical, auditory, mathematical, or neurobiological. A focus is on the hotly debated topic of what aspects of ICE animals actually exploit neuronally to localize a sound source....

  15. Skating on slippery ice

    Directory of Open Access Journals (Sweden)

    J. M. J. van Leeuwen


    Full Text Available The friction of a stationary moving skate on smooth ice is investigated, in particular in relation to the formation of a thin layer of water between skate and ice. It is found that the combination of ploughing and sliding gives a friction force that is rather insensitive for parameters such as velocity and temperature. The weak dependence originates from the pressure adjustment inside the water layer. For instance, high velocities, which would give rise to high friction, also lead to large pressures, which, in turn, decrease the contact zone and so lower the friction. The theory is a combination and completion of two existing but conflicting theories on the formation of the water layer.

  16. Sports: Ice -Doping Time


    Barys Tasman


    In 2013 the systematic degradation of Belarusian sports continued, which was most vivid in the mass and most popular kinds of sports – soccer, hockey, track and field athletics, and also in the traditional Olympic disciplines – cycling, boxing, weight-lifting. The national ice hockey team lost the qualification tournament and failed to get to the Olympic Games in Sochi. The football national team took the last place in the qualifying group tournament at the 2014 World Cup. At the World Forum ...

  17. Car engine breather icing


    Horoufi, Aryan


    Icing in an engine breather system can block the engine breather pipe, cause excessive crankcase pressure and degrade the engine performance. In this project, a numerical study, experimental tests and CFD analysis are employed in order to understand condensation and the extent of freezing inside a vertical pipe, a horizontal pipe and a T-joint pipe which are exposed to an external convective cooling. The pipe internal flow is assumed to be a vapour/air mixture. This study has l...

  18. Helicopter Icing Review. (United States)


    on the ground or could be injurious to per- sons on the ground. Ice on the rotor hub and fuselage may become critical in a flight transitioning from...0 uE -4- c -) U. c-j -- 0- CL) - lCA AC) O C-)) 41 4J 4- -C -I Q -. x 0 s- =U. A S (U C C -- () : -) -_ __ _r__ . -( ___ 4)a -)r ’ ) - 0 n - 1 3092

  19. Ice condenser experimental plan

    International Nuclear Information System (INIS)

    Kannberg, L.D.; Piepel, G.F.; Owczarski, P.C.; Liebetrau, A.M.


    An experimental plan is being developed to validate the computer code ICEDF. The code was developed to estimate the extent of aerosol retention in the ice compartments of pressurized water reactor ice condenser containment systems during severe accidents. The development of the experimental plan began with review of available information on the conditions under which the code will be applied. Computer-generated estimates of thermohydraulic and aerosol conditions entering the ice condenser were evaluated and along with other information, used to generate design criteria. The design criteria have been used for preliminary test assembly design and for generation of statistical test designs. Consideration of the phenomena to be evaluated in the testing program, as well as equipment and measurement limitations, have led to changes in the design criteria and to subsequent changes in the test assembly design and statistical test design. The overall strategy in developing the experimental plan includes iterative generation and evaluation of candidate test designs using computer codes for statistical test design and ICEDF for estimation of experimental results. Estimates of experimental variability made prior to actual testing will be verified by replicate testing at preselected design points

  20. Drinking water systems, hydrology, and childhood gastrointestinal illness in Central and Northern Wisconsin. (United States)

    Uejio, Christopher K; Yale, Steven H; Malecki, Kristen; Borchardt, Mark A; Anderson, Henry A; Patz, Jonathan A


    This study investigated if the type of drinking water source (treated municipal, untreated municipal, and private well water) modifies the effect of hydrology on childhood (aged hydrologic and weather conditions with childhood gastrointestinal illness from 1991 to 2010. The Central and Northern Wisconsin study area includes households using all 3 types of drinking water systems. Separate time series models were created for each system and half-year period (winter/spring, summer/fall). More precipitation (summer/fall) systematically increased childhood gastrointestinal illness in municipalities accessing untreated water. The relative risk of contracting gastrointestinal illness was 1.4 in weeks with 3 centimeters of precipitation and 2.4 in very wet weeks with 12 centimeters of precipitation. By contrast, gastrointestinal illness in private well and treated municipal areas was not influenced by hydrologic conditions, although warmer winter temperatures slightly increased incidence. Our study suggests that improved drinking water protection, treatment, and delivery infrastructure may improve public health by specifically identifying municipal water systems lacking water treatment that may transmit waterborne disease.

  1. Data handling and validation from Wisconsin's remote vehicle emissions sensing studies (United States)

    Rendahl, Craig S.


    The Wisconsin Department of Natural Resources and Department of Transportation (WDOT) are conducting a joint study to determine the effectiveness of applying optical sensing techniques to vehicular emission monitoring. Two field studies using Remote Sensing Technologies, Inc. remote sensing equipment was conducted in 1993 and 1994. This paper describes the data handling and data validation activities of these studies, including identification of data elements. Data handling was performed by the same people who conducted the 180,000 vehicle emissions tests. A contemporary commercial spreadsheet from Borland International, Inc. was used to import the raw data from the remote sensor. The data was reviewed with the spreadsheet then moved into a Borland relational database product. The relational database permitted structured queries against databases of vehicle inspection/maintenance (I/M) data from WDOT, National Insurance Crime Bureau, and EnviroTest. We determined effective cut points for vehicles of different ages which delineated high-polluting vehicles (gross emitters) from vehicles in compliance. The I/M data was also used to intercompare the remote sensing results with traditional testing results. Remote sensing test results were then compared for errors of commission and omission with respect to I/M test. Ultimately, this remote sensing database technique could serve as a means for identifying gross emitters who would be required to visit an I/M facility for an out-of-cycle emissions test.

  2. Using ice melting and ice rolling technologies to remove ice from sub-transmission and transmission lines at Manitoba Hydro

    International Nuclear Information System (INIS)

    Farias, A. R.


    Development of an of an Ice Storm Management program by Manitoba Hydro to reduce ice storm damage to its 8 kV feeders to 115 kV transmission lines, is discussed. The program consists of the de-icing of overhead lines, either by ice melting, or ice rolling. Ice melting involves the placement of a three-phase short at a calculated point. The term ice rolling denotes a process of mechanically stripping the ice from conductors. The most recent major ice storm experienced by Manitoba Hydro was in the winter of 1997/1998. During the period from February 6 to February 17, 1998, a total of 83 'ice melt' procedures were performed to melt the ice from 2,628 km of overhead line (7,883 km of conductor), in addition to 'ice rolling'. This paper describes Manitoba Hydro's 25-years' experience with ice melting and it also describes the advantages and disadvantages of both ice melting and ice rolling. Although not a panacea to combat the effects of ice storms, ice melting was found to be the most effective way of removing ice from overhead transmission and sub-transmission lines. Ice rolling was also found to be effective. Other tools that have been found to be useful by various utilities in combating ice storm damage include improved structure and line design, system design that provide more redundancies and emergency sources, and standby generators at critical load points

  3. A Systems-Level Perspective on Engine Ice Accretion (United States)

    May, Ryan D.; Guo, Ten-Huei; Simon, Donald L.


    The accretion of ice in the compression system of commercial gas turbine engines operating in high ice water content conditions is a safety issue being studied by the aviation sector. While most of the research focuses on the underlying physics of ice accretion and the meteorological conditions in which accretion can occur, a systems-level perspective on the topic lends itself to potential near-term operational improvements. This work focuses on developing an accurate and reliable algorithm for detecting the accretion of ice in the low pressure compressor of a generic 40,000 lbf thrust class engine. The algorithm uses only the two shaft speed sensors and works regardless of engine age, operating condition, and power level. In a 10,000-case Monte Carlo simulation, the detection approach was found to have excellent capability at determining ice accretion from sensor noise with detection occurring when ice blocks an average of 6.8% of the low pressure compressor area. Finally, an initial study highlights a potential mitigation strategy that uses the existing engine actuators to raise the temperature in the low pressure compressor in an effort to reduce the rate at which ice accretes.

  4. Lake ice records used to detect historical and future climatic changes (United States)

    Robertson, Dale M.; Ragotzkie, R.A.; Magnuson, John J.


    Historical ice records, such as freeze and breakup dates and the total duration of ice cover, can be used as a quantitative indicator of climatic change if long homogeneous records exist and if the records can be calibrated in terms of climatic changes. Lake Mendota, Wisconsin, has the longest uninterrupted ice records available for any lake in North America dating back to 1855. These records extend back prior to any reliable air temperature data in the midwestern region of the U.S. and demonstrate significant warming of approximately 1.5 °C in fall and early winter temperatures and 2.5 °C in winter and spring temperatures during the past 135 years. These changes are not completely monotonie, but rather appear as two shorter periods of climatic change in the longer record. The first change was between 1875 and 1890, when fall, winter, and spring air temperatures increased by approximately 1.5 °C. The second change, earlier ice breakup dates since 1979, was caused by a significant increase in winter and early spring air temperatures of approximately 1.3 °C. This change may be indicative of shifts in regional climatic patterns associated with global warming, possibly associated with the ‘Greenhouse Effect’.

  5. Co-distribution of seabirds and their polar cod prey near the ice edge in southern Baffin Bay

    DEFF Research Database (Denmark)

    LeBlanc, Mathieu; Gauthier, S; Mosbech, Anders

    species, and age-1 polar cod found in bird stomachs were likely individuals associated to ice. At a large scale of hundreds of kilometers, seabirds and age-0 polar cod were more abundant in ice-covered habitats (30 to 100% ice concentration). At medium and small scale of 12.5 and 1 km respectively...... fish. The ongoing climate warming and the decrease in sea-ice extent may lead to the confinement of sympagic age-1 polar cod in northernmost regions of the Arctic and force seabirds to travel farther to reach more productive ice edges.......Polar cod (Boreogadus saida) is the main prey of several arctic predators including many seabird species. Ice edges are known as important feeding locations for seabirds. How polar cod density affects arctic seabird distribution around offshore ice edges is still unclear. We tested the hypothesis...

  6. Modelling ice-ocean interaction in ice shelf crevasses (United States)

    Jordan, J. R.; Holland, P.; Piggott, M. D.; Jenkins, A.; Kimura, S.


    Ocean freezing within ice shelf basal crevasses could potentially act as a stabilising influence on ice shelves, however ice-ocean interaction and ocean dynamics within these crevasses are as yet poorly understood. To this end, an idealised two-dimensional model of an ice shelf basal crevasse has been developed using Fluidity-ICOM, a finite element ocean model using an unstructured mesh. A model of frazil ice formation and deposition has been incorporated into Fluidity-ICOM to better represent the freezing process. Model results show that freezing at the top of crevasses leads to the formation of an unstable overturning circulation due to the rejection of dense, salty water. The strength of this circulation, which is increased by the formation of frazil ice, is found to be the dominant factor influencing the total freezing rate. Frazil ice precipitation is found to be responsible for roughly one sixth of ice formation on the top of the basal crevasse, with direct freezing, enhanced by the complex dynamics of the overturning circulation, responsible for the rest. Increasing the frazil crystal radii used in the model has little impact on the amount of frazil ice deposition but does increase the amount of direct freezing. Significant melting and freezing was found to occur on the walls of the crevasse due to the strong overturning circulation. With previous modelling approaches it has not been possible to simulate this strong circulation, with water rising up one side of the crevasse and down the other.

  7. IceCube systematic errors investigation: Simulation of the ice

    Energy Technology Data Exchange (ETDEWEB)

    Resconi, Elisa; Wolf, Martin [Max-Planck-Institute for Nuclear Physics, Heidelberg (Germany); Schukraft, Anne [RWTH, Aachen University (Germany)


    IceCube is a neutrino observatory for astroparticle and astronomy research at the South Pole. It uses one cubic kilometer of Antartica's deepest ice (1500 m-2500 m in depth) to detect Cherenkov light, generated by charged particles traveling through the ice, with an array of phototubes encapsulated in glass pressure spheres. The arrival time as well as the charge deposited of the detected photons represent the base measurements that are used for track and energy reconstruction of those charged particles. The optical properties of the deep antarctic ice vary from layer to layer. Measurements of the ice properties and their correct modeling in Monte Carlo simulation is then of primary importance for the correct understanding of the IceCube telescope behavior. After a short summary about the different methods to investigate the ice properties and to calibrate the detector, we show how the simulation obtained by using this information compares to the measured data and how systematic errors due to uncertain ice properties are determined in IceCube.

  8. Time Dependent Frictional Changes in Ice due to Contact Area Changes (United States)

    Sevostianov, V.; Lipovsky, B. P.; Rubinstein, S.; Dillavou, S.


    Sliding processes along the ice-bed interface of Earth's great ice sheets are the largest contributor to our uncertainty in future sea level rise. Laboratory experiments that have probed sliding processes have ubiquitously shown that ice-rock interfaces strengthen while in stationary contact (Schulson and Fortt, 2013; Zoet et al., 2013; McCarthy et al., 2017). This so-called frictional ageing effect may have profound consequences for ice sheet dynamics because it introduces the possibility of basal strength hysteresis. Furthermore this effect is quite strong in ice-rock interfaces (more than an order of magnitude more pronounced than in rock-rock sliding) and can double in frictional strength in a matter of minutes, much faster than most frictional aging (Dieterich, 1972; Baumberger and Caroli, 2006). Despite this importance, the underling physics of frictional ageing of ice remain poorly understood. Here we conduct laboratory experiments to image the microscopic points of contact along an ice-glass interface. We optically measure changes in the real area of contact over time using measurements of this reflected optical light intensity. We show that contact area increases with time of stationary contact. This result suggests that thermally enhanced creep of microscopic icy contacts is responsible for the much larger frictional ageing observed in ice-rock versus rock-rock interfaces. Furthermore, this supports a more physically detailed description of the thermal dependence of basal sliding than that used in the current generation of large scale ice sheet models.

  9. 76 FR 35901 - National Institute on Aging; Notice of Closed Meetings (United States)


    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute on Aging..., National Institute on Aging, National Institutes of Health, 7201 Wisconsin Avenue, Suite 2C-212, Bethesda... of Committee: National Institute on Aging Special Emphasis Panel, Cognitive Aging Success. Date...

  10. 77 FR 58854 - National Institute on Aging; Notice of Closed Meetings (United States)


    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute on Aging... personal privacy. Name of Committee: National Institute on Aging Special Emphasis Panel Cognitive Aging... Institutes on Aging, National Institutes of Health, 7201 Wisconsin Avenue, Suite 2C212, Bethesda, MD 20892...

  11. Obliquity-paced Pliocene West Antarctic ice sheet oscillations (United States)

    Naish, T.; Powell, R.; Levy, R.; Wilson, G.; Scherer, R.; Talarico, F.; Krissek, L.; Niessen, F.; Pompilio, M.; Wilson, T.; Carter, L.; DeConto, R.; Huybers, P.; McKay, R.; Pollard, D.; Ross, J.; Winter, D.; Barrett, P.; Browne, G.; Cody, R.; Cowan, E.; Crampton, J.; Dunbar, G.; Dunbar, N.; Florindo, F.; Gebhardt, C.; Graham, I.; Hannah, M.; Hansaraj, D.; Harwood, D.; Helling, D.; Henrys, S.; Hinnov, L.; Kuhn, G.; Kyle, P.; Laufer, A.; Maffioli, P.; Magens, D.; Mandernack, K.; McIntosh, W.; Millan, C.; Morin, R.; Ohneiser, C.; Paulsen, T.; Persico, D.; Raine, I.; Reed, J.; Riesselman, C.; Sagnotti, L.; Schmitt, D.; Sjunneskog, C.; Strong, P.; Taviani, M.; Vogel, S.; Wilch, T.; Williams, T.


    Thirty years after oxygen isotope records from microfossils deposited in ocean sediments confirmed the hypothesis that variations in the Earth's orbital geometry control the ice ages1, fundamental questions remain over the response of the Antarctic ice sheets to orbital cycles2. Furthermore, an understanding of the behaviour of the marine-based West Antarctic ice sheet (WAIS) during the 'warmer-than-present' early-Pliocene epoch (5–3 Myr ago) is needed to better constrain the possible range of ice-sheet behaviour in the context of future global warming3. Here we present a marine glacial record from the upper 600 m of the AND-1B sediment core recovered from beneath the northwest part of the Ross ice shelf by the ANDRILL programme and demonstrate well-dated, 40-kyr cyclic variations in ice-sheet extent linked to cycles in insolation influenced by changes in the Earth's axial tilt (obliquity) during the Pliocene. Our data provide direct evidence for orbitally induced oscillations in the WAIS, which periodically collapsed, resulting in a switch from grounded ice, or ice shelves, to open waters in the Ross embayment when planetary temperatures were up to 3 °C warmer than today4 and atmospheric CO2 concentration was as high as 400 p.p.m.v. (refs 5, 6). The evidence is consistent with a new ice-sheet/ice-shelf model7 that simulates fluctuations in Antarctic ice volume of up to +7 m in equivalent sea level associated with the loss of the WAIS and up to +3 m in equivalent sea level from the East Antarctic ice sheet, in response to ocean-induced melting paced by obliquity. During interglacial times, diatomaceous sediments indicate high surface-water productivity, minimal summer sea ice and air temperatures above freezing, suggesting an additional influence of surface melt8 under conditions of elevated CO2.

  12. Ice blockage of water intakes

    International Nuclear Information System (INIS)

    Carey, K.L.


    The ice blockage of water intake structures can pose serious threats to the availability of cooling water at thermal power plants. Using information gained from a literature search and general knowledge of the problem, ice blockage difficulties are described as they may occur in rivers, lakes, reservoirs, and estuaries, and as they may affect intakes either at the surface or submerged. To further enable understanding of these problems, characteristics of both surface sheet ice and frazil ice are examined, namely, formational processes, sizes, thicknesses, movement or mobility, and modes of blockage or adhesion. Case histories of incidents of ice blockage of intakes are given by means of excerpts from the technical literature. Lastly, a brief overview is provided on the matter of solving ice blockage problems, either through original design, post-construction modification, or revised operational techniques

  13. Is there 1.5-million-year-old ice near Dome C, Antarctica? (United States)

    Parrenin, Frédéric; Cavitte, Marie G. P.; Blankenship, Donald D.; Chappellaz, Jérôme; Fischer, Hubertus; Gagliardini, Olivier; Masson-Delmotte, Valérie; Passalacqua, Olivier; Ritz, Catherine; Roberts, Jason; Siegert, Martin J.; Young, Duncan A.


    Ice sheets provide exceptional archives of past changes in polar climate, regional environment and global atmospheric composition. The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ˜ 800 000 years. Obtaining an older paleoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we use internal isochrones, identified from airborne radar coupled to ice-flow modelling to estimate the age of basal ice along transects in the Dome C area. Three glaciological properties are inferred from isochrones: surface accumulation rate, geothermal flux and the exponent of the Lliboutry velocity profile. We find that old ice (> 1.5 Myr, 1.5 million years) likely exists in two regions: one ˜ 40 km south-west of Dome C along the ice divide to Vostok, close to a secondary dome that we name Little Dome C (LDC), and a second region named North Patch (NP) located 10-30 km north-east of Dome C, in a region where the geothermal flux is apparently relatively low. Our work demonstrates the value of combining radar observations with ice flow modelling to accurately represent the true nature of ice flow, and understand the formation of ice-sheet architecture, in the centre of large ice sheets.

  14. Is there 1.5-million-year-old ice near Dome C, Antarctica?

    Directory of Open Access Journals (Sweden)

    F. Parrenin


    Full Text Available Ice sheets provide exceptional archives of past changes in polar climate, regional environment and global atmospheric composition. The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC, reaching ∼ 800 000 years. Obtaining an older paleoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we use internal isochrones, identified from airborne radar coupled to ice-flow modelling to estimate the age of basal ice along transects in the Dome C area. Three glaciological properties are inferred from isochrones: surface accumulation rate, geothermal flux and the exponent of the Lliboutry velocity profile. We find that old ice (> 1.5 Myr, 1.5 million years likely exists in two regions: one ∼ 40 km south-west of Dome C along the ice divide to Vostok, close to a secondary dome that we name Little Dome C (LDC, and a second region named North Patch (NP located 10–30 km north-east of Dome C, in a region where the geothermal flux is apparently relatively low. Our work demonstrates the value of combining radar observations with ice flow modelling to accurately represent the true nature of ice flow, and understand the formation of ice-sheet architecture, in the centre of large ice sheets.

  15. Lichens promote flowering Opuntia fragilis in west-central Wisconsin (United States)

    Bennett, J.P.; Bornar, C.R.; Harrington, C.A.


    Clumps of the cactus Opuntia fragilis growing in association with mats of the lichens Cladina mitis, Cladina rangiferina and a spikemoss, Selaginella rupestris, were discovered in an agricultural field in Pepin County, Wisconsin, that had been abandoned for over 50 y. The association appeared to be beneficial to the cactus, which flowered almost exclusively in the presence of lichens. Of 294 cactus clumps examined in 2001, 127 grew in the presence of lichen mats and, of these, 24 flowered, producing 91 flowers, while none of the cacti growing in the absence of lichens flowered. In 2002, 19 out of 265 cactus clumps flowered, all but one in the presence of lichens. All sizes of cacti in the presence of lichens flowered and the probability of flowering increased with cactus size. In addition, the cacti that flowered had cladodes that were on average 19% heavier than those of cacti that did not flower. The presence of lichens lowered summer soil temperatures 2a??4 C compared to soil temperatures in the absence of lichens. Cooler soil temperatures conserve soil moisture better, which may enhance flowering in these cacti.

  16. 78 FR 29612 - Prevailing Rate Systems; Redefinition of the Minneapolis-St. Paul, MN, and Southwestern Wisconsin... (United States)


    ...: Minnesota: Benton Big Stone Blue Earth Brown Chippewa Cottonwood Dodge Douglas Faribault Freeborn Goodhue... plus: Minnesota: Fillmore Houston Winona Wisconsin: Barron Buffalo Clark Crawford Dunn Florence Forest...




  18. The last North American ice sheet and mantle viscosity from glacial rebound analyses. (United States)

    Lambeck, Kurt; Purcell, Anthony; Zhao, Jason


    drainage of the palaeo-lakes to global sea level rise is small, American Late Wisconsin ice sheet and mantle viscosity from glacial rebound analyses' is in press in J. Quaternary Science Reviews

  19. Dynamics of the Greenland Ice Sheet over multiple timescales

    DEFF Research Database (Denmark)

    Kjeldsen, Kristian Kjellerup

    Since the 1990s mass loss of the Greenland Ice Sheet has accelerated substantially increasing its contribution to global sea level rise, especially during the past decade. Even though the current global sea level budget is well understood, providing better estimates of the mass loss is essential....../crossshelf troughs. Warming of ocean temperatures is suggested as being a main driver for periodic dynamic ice loss events in northwest Greenland while cooling of ocean temperatures around southern Greenland, in conjunction with increased snow accumulation, is found to drive a rapid readvance of glaciers in response...... to the onset of the Little Ice Age. Furthermore this thesis shows that the thinning pattern of the last decade in southern Greenland compares well with that of the entire 20th century, thus the present sensitivity distribution will arguably hold for future ice sheet mass loss until marine outlet glaciers...

  20. [Normative data on tests for frontal lobe functions: Trail Making Test, Verbal fluency, Wisconsin Card Sorting Test (Keio version)]. (United States)

    Abe, Mitsuyo; Suzuki, Kyoko; Okada, Kazue; Miura, Rina; Fujii, Toshikatsu; Etsurou, Mori; Yamadori, Atsushi


    Trail Making Test (TMT Part A, B), Verbal fluency test (phonemic, semantic) and Wisconsin Card Sorting Test (Keio version : KWCST) are useful to evaluate frontal lobe functions and are commonly used in clinical settings. However, few normative data for aged Japanese have been reported. We collected normative data on these tests in elderly population, and examined the effects of age and education on the performance of these tests. Seventy-six healthy adults, aged 45 to 74 years, participated in this study. Subjects were classified into three groups by age (45-54, 55-64, 65-74). Fifty-five subjects repeated the same tests after 6 months to examine the test-retest reliability. Performance of the TMT Part A was correlated with age (r= 0.530) and that of Part B was correlated with age (r=0.500) and education (r=-0.340). Performance on both phonemic and semantic fluency was correlated with education (phonemic: r=0.357, semantic: r=0.279). Number of Categories Achieved (CA) of KWCST was correlated with education (r=0.376). The test-retest reliability of all these tests except for semantic verbal fluency and difficulty maintaining set (DMS) of KWCST was good enough for longitudinal studies.

  1. Diffuse scattering in Ih ice

    International Nuclear Information System (INIS)

    Wehinger, Björn; Krisch, Michael; Bosak, Alexeï; Chernyshov, Dmitry; Bulat, Sergey; Ezhov, Victor


    Single crystals of ice Ih, extracted from the subglacial Lake Vostok accretion ice layer (3621 m depth) were investigated by means of diffuse x-ray scattering and inelastic x-ray scattering. The diffuse scattering was identified as mainly inelastic and rationalized in the frame of ab initio calculations for the ordered ice XI approximant. Together with Monte-Carlo modelling, our data allowed reconsidering previously available neutron diffuse scattering data of heavy ice as the sum of thermal diffuse scattering and static disorder contribution. (paper)

  2. First investigations of an ice core from Eisriesenwelt cave (Austria

    Directory of Open Access Journals (Sweden)

    B. May


    Full Text Available Investigations into the genesis and dynamical properties of cave ice are essential for assessing the climate significance of these underground glaciers. We drilled an ice core through a 7.1 m-thick ice body filling a large cavern of the dynamic ice cave Eisenriesenwelt (Austria. In addition to visual core inspections, quasi-continuous measurements at 2 cm resolution comprised particulate matter, stable water isotope (δ18O, δD and electrolytic conductivity profiles supplemented by specifically selected samples analyzed for tritium and radiocarbon. We found that recent ablation led to an almost complete loss of bomb-derived tritium removing any ice accumulated since, at least, the early fifties leaving the actual ice surface even below the natural tritium level. The small particulate organic masses rendered radiocarbon dating inconclusive, though a crude estimate gave a basal ice age in the order of several thousand years. The visual stratigraphy and all investigated parameters showed a clear dichotomy between the upper 2 m and the bottom 3 m of the core, which points to a substantial change in the ice formation process. Main features of the core comprise the changing appearance and composition of distinct cryocalcite layers, extremely low total ion content and a surprisingly high variability of the isotope signature. Co-isotope evaluation (δD versus δ18O of the core in comparison with data from precipitation and karst spring water clearly indicate that ice formation is governed by (slow freezing of dripping water.

  3. Modelling the Early Weichselian Eurasian Ice Sheets: role of ice shelves and influence of ice-dammed lakes

    Directory of Open Access Journals (Sweden)

    V. Peyaud


    Full Text Available During the last glaciation, a marine ice sheet repeatedly appeared in Eurasia. The floating part of this ice sheet was essential to its rapid extension over the seas. During the earliest stage (90 kyr BP, large ice-dammed lakes formed south of the ice sheet. These lakes are believed to have cooled the climate at the margin of the ice. Using an ice sheet model, we investigated the role of ice shelves during the inception and the influence of ice-dammed lakes on the ice sheet evolution. Inception in Barents sea seems due to thickening of a large ice shelf. We observe a substantial impact of the lakes on the evolution of the ice sheets. Reduced summer ablation enhances ice extent and thickness, and the deglaciation is delayed by 2000 years.

  4. A correction for in situ 14C in Antarctic ice with 14CO

    NARCIS (Netherlands)

    Roijen, J.J. van; Borg, K. van der; Jong, A.F.M. de; Oerlemans, J.


    We use a dry extraction method to obtain trapped C02 of shallow ice cores from a blue ice area of East Antarctica. In-situ-produced 14C extracted in 14CO2 and 10CO concentrations show a mean ratio of 3.4 ± 0.4. Correction for insitu 14CO2 resulted in ice ages within 7-13 ka. The accumulation and

  5. Multi-Decadal Averages of Basal Melt for Ross Ice Shelf, Antarctica Using Airborne Observations (United States)

    Das, I.; Bell, R. E.; Tinto, K. J.; Frearson, N.; Kingslake, J.; Padman, L.; Siddoway, C. S.; Fricker, H. A.


    Changes in ice shelf mass balance are key to the long term stability of the Antarctic Ice Sheet. Although the most extensive ice shelf mass loss currently is occurring in the Amundsen Sea sector of West Antarctica, many other ice shelves experience changes in thickness on time scales from annual to ice age cycles. Here, we focus on the Ross Ice Shelf. An 18-year record (1994-2012) of satellite radar altimetry shows substantial variability in Ross Ice Shelf height on interannual time scales, complicating detection of potential long-term climate-change signals in the mass budget of this ice shelf. Variability of radar signal penetration into the ice-shelf surface snow and firn layers further complicates assessment of mass changes. We investigate Ross Ice Shelf mass balance using aerogeophysical data from the ROSETTA-Ice surveys using IcePod. We use two ice-penetrating radars; a 2 GHz unit that images fine-structure in the upper 400 m of the ice surface and a 360 MHz radar to identify the ice shelf base. We have identified internal layers that are continuous along flow from the grounding line to the ice shelf front. Based on layer continuity, we conclude that these layers must be the horizons between the continental ice of the outlet glaciers and snow accumulation once the ice is afloat. We use the Lagrangian change in thickness of these layers, after correcting for strain rates derived using modern day InSAR velocities, to estimate multidecadal averaged basal melt rates. This method provides a novel way to quantify basal melt, avoiding the confounding impacts of spatial and short-timescale variability in surface accumulation and firn densification processes. Our estimates show elevated basal melt rates (> -1m/yr) around Byrd and Mullock glaciers within 100 km from the ice shelf front. We also compare modern InSAR velocity derived strain rates with estimates from the comprehensive ground-based RIGGS observations during 1973-1978 to estimate the potential magnitude of

  6. Ice storm `98

    Energy Technology Data Exchange (ETDEWEB)

    Soulard, F.; Trant, D.; Filoso, J.; Van Wesenbeeck, P. [Statistics Canada, Ottawa, ON (Canada). Environment Statistics Program


    As much as 100 millimeters of freezing rain fell on central and eastern Canada between January 4 to 10, 1998. This study concentrates on Canada`s St. Lawrence River Valley where total precipitation exceeded 73 mm in Kingston, 85 mm in Ottawa and 100 mm in areas south of Montreal. By comparison, the largest previously recorded ice storms left between 30 and 40 mm of ice. A state of emergency was declared for the affected regions. 56 per cent of Quebec`s population and 11 per cent of Ontario`s population were affected by the storm. Over 1000 power transmission towers collapsed and more than 30,000 wooden utility poles were brought down. In Quebec, nearly 1.4 million customers were left without electricity. In Ontario that number was about 230,000. While some manufacturers benefited directly from the storm, including makers of hydro and telephone poles, batteries and specialized electrical equipment, the overall economic losses for Montreal and Ottawa were high as estimates run to $585 million and $114 million, respectively. Almost 5 million sugar maple taps in Quebec and Ontario were located and suffered some damage in the affected areas. Nearly one-quarter (274,000) of all dairy cows were also located in the affected areas. Since in the absence of electricity they could not be milked, many of them suffered from mastitis. Many succumbed, others that survived may never attain their former level of productivity. As of June 1998, over 600,000 insurance claims totaling one billion dollars had been filed by Canadian households and businesses from the area affected by the ice storm.1 fig.

  7. Improved ice loss estimate of the northwestern Greenland ice sheet

    NARCIS (Netherlands)

    Kjeldsen, K.K.; Khan, S.A.; van den Broeke, M.R.; van Angelen, J.H.


    We estimate ice volume change rates in the northwest Greenland drainage basin during 2003–2009 using Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data. Elevation changes are often reported to be largest near the frontal portion of outlet glaciers. To improve the volume change

  8. Eulerian method for ice crystal icing in turbofan engines

    NARCIS (Netherlands)

    Norde, Ellen


    The newer generations of high-bypass-ratio engines are susceptible to the ingestion of small ice crystals which may cause engine power loss or damage. The research presented in this thesis focusses on the development of a computational method for in-engine ice crystal accretion. The work has been

  9. Wave-Ice and Air-Ice-Ocean Interaction During the Chukchi Sea Ice Edge Advance (United States)


    Chukchi Sea in the late summer have potentially changed the impact of fall storms by creating wave fields in the vicinity of the advancing ice edge. A...related to variability in storm and wave activity and changes in ice type and set the historical context for the Sea State field observations. Work...Doble Wave Climate and Wave Mixing in the Marginal Ice Zones of Arctic Seas: Observations and Modeling Babanin Storm Flux: Heat and Momentum

  10. Ice-driven CO2 feedback on ice volume

    Directory of Open Access Journals (Sweden)

    W. F. Ruddiman


    Full Text Available The origin of the major ice-sheet variations during the last 2.7 million years is a long-standing mystery. Neither the dominant 41 000-year cycles in δ18O/ice-volume during the late Pliocene and early Pleistocene nor the late-Pleistocene oscillations near 100 000 years is a linear ('Milankovitch' response to summer insolation forcing. Both responses must result from non-linear behavior within the climate system. Greenhouse gases (primarily CO2 are a plausible source of the required non-linearity, but confusion has persisted over whether the gases force ice volume or are a positive feedback. During the last several hundred thousand years, CO2 and ice volume (marine δ18O have varied in phase at the 41 000-year obliquity cycle and nearly in phase within the ~100 000-year band. This timing rules out greenhouse-gas forcing of a very slow ice response and instead favors ice control of a fast CO2 response. In the schematic model proposed here, ice sheets responded linearly to insolation forcing at the precession and obliquity cycles prior to 0.9 million years ago, but CO2 feedback amplified the ice response at the 41 000-year period by a factor of approximately two. After 0.9 million years ago, with slow polar cooling, ablation weakened. CO2 feedback continued to amplify ice-sheet growth every 41 000 years, but weaker ablation permitted some ice to survive insolation maxima of low intensity. Step-wise growth of these longer-lived ice sheets continued until peaks in northern summer insolation produced abrupt deglaciations every ~85 000 to ~115 000 years. Most of the deglacial ice melting resulted from the same CO2/temperature feedback that had built the ice sheets. Several processes have the northern geographic origin, as well as the requisite orbital tempo and phasing, to be candidate mechanisms for ice-sheet control of CO2 and their own feedback.

  11. The health of Antarctic ice shelves (United States)

    Gagliardini, Olivier


    The thinning of floating ice shelves around Antarctica enhances upstream ice flow, contributing to sea-level rise. Ice-shelf thinning is now shown to influence glacial movement over much larger distances than previously thought.

  12. Great Lakes Ice Charts, Version 1 (United States)

    National Aeronautics and Space Administration — These charts show ice extent and concentration three times weekly during the ice season, for all lakes except Ontario, from the 1973/74 ice season through the...

  13. Arctic Sea Ice Freeboard and Thickness (United States)

    National Aeronautics and Space Administration — This data set provides measurements of sea ice freeboard and sea ice thickness for the Arctic region. The data were derived from measurements made by from the Ice,...

  14. Ion implantation in ices

    International Nuclear Information System (INIS)

    Strazzulla, G.; Baratta, G.A.; Palumbo, M.E.; Satorre, M.A.


    We have studied, by in situ infrared spectroscopy, some effects due to ion implantation in frozen ices. In particular mixtures containing C, N and O atoms (e.g., N 2 :H 2 O:CH 4 ) have been irradiated with unreactive (noble gases) ions: the resulting alteration of the frozen sample induces the formation of other molecules (e.g., CO 2 , R- - -OCN, CO and HCN) and of a refractory organic residue. Similar products are formed when mixtures containing only C and O atoms (e.g., H 2 O:CH 4 ) are irradiated with N ions, i.e. molecular species that include the projectile are formed. These results are important, in particular for their applications to planetary physics. In planetary environments ice thickness is usually much larger than the penetration depth of the relevant ion populations (solar wind ions, magnetospheric particles, etc.) and ion implantation phenomena are expected. Our results indicate that some molecular species observed on icy planetary surfaces could not be native of that object but formed by ion irradiation and/or by implantation of reactive ions

  15. Ice hockey injuries. (United States)

    Benson, Brian W; Meeuwisse, Willem H


    This article reviews the distribution and determinants of injuries reported in the pediatric ice hockey literature, and suggests potential injury prevention strategies and directions for further research. Thirteen electronic databases, the ISI Web of Science, and 'grey literature' databases were searched using a combination of Medical Subject Headings and text words to identify potentially relevant articles. The bibliographies of selected studies were searched to identify additional articles. Studies were selected for review based on predetermined inclusion and exclusion criteria. A comparison between studies on this topic area was difficult due to the variability in research designs, definition of injury, study populations, and measurements used to assess injury. The majority of injuries were sustained during games compared with practices. The two most commonly reported injuries were sprains/strains and contusions. Players competing at the Minor hockey, High School, and Junior levels of competition sustained most of their injuries to the upper extremity, head, and lower extremity, respectively. The primary mechanism of injury was body checking, followed by stick and puck contact. The frequency of catastrophic eye injuries has been significantly reduced with the world-wide mandation of full facial protection for all Minor hockey players. Specific hockey-related injury risk factors are poorly delineated and rarely studied among pediatric ice hockey players leaving large gaps in the knowledge of appropriate prevention strategies. Risk management strategies should be focused at avoiding unnecessary foreseeable risk, and controlling the risks inherent to the sport. Suggestions for injury prevention and future research are discussed.

  16. The 2016 groundwater flow model for Dane County, Wisconsin (United States)

    Parsen, Michael J.; Bradbury, Kenneth R.; Hunt, Randall J.; Feinstein, Daniel T.


    A new groundwater flow model for Dane County, Wisconsin, replaces an earlier model developed in the 1990s by the Wisconsin Geological and Natural History Survey (WGNHS) and the U.S. Geological Survey (USGS). This modeling study was conducted cooperatively by the WGNHS and the USGS with funding from the Capital Area Regional Planning Commission (CARPC). Although the overall conceptual model of the groundwater system remains largely unchanged, the incorporation of newly acquired high-quality datasets, recent research findings, and improved modeling and calibration techniques have led to the development of a more detailed and sophisticated model representation of the groundwater system. The new model is three-dimensional and transient, and conceptualizes the county’s hydrogeology as a 12-layer system including all major unlithified and bedrock hydrostratigraphic units and two high-conductivity horizontal fracture zones. Beginning from the surface down, the model represents the unlithified deposits as two distinct model layers (1 and 2). A single layer (3) simulates the Ordovician sandstone and dolomite of the Sinnipee, Ancell, and Prairie du Chien Groups. Sandstone of the Jordan Formation (layer 4) and silty dolostone of the St. Lawrence Formation (layer 5) each comprise separate model layers. The underlying glauconitic sandstone of the Tunnel City Group makes up three distinct layers: an upper aquifer (layer 6), a fracture feature (layer 7), and a lower aquifer (layer 8). The fracture layer represents a network of horizontal bedding-plane fractures that serve as a preferential pathway for groundwater flow. The model simulates the sandstone of the Wonewoc Formation as an upper aquifer (layer 9) with a bedding-plane fracture feature (layer 10) at its base. The Eau Claire aquitard (layer 11) includes shale beds within the upper portion of the Eau Claire Formation. This layer, along with overlying bedrock units, is mostly absent in the preglacially eroded valleys along

  17. Snow, ice and solar radiation

    NARCIS (Netherlands)

    Kuipers Munneke, P.


    The snow-covered ice sheets of Antarctica and Greenland reflect most of the incoming solar radiation. The reflectivity, commonly called the albedo, of snow on these ice sheets has been observed to vary in space and time. In this thesis, temporal and spatial changes in snow albedo is found to depend

  18. The physics of ice cream (United States)

    Clarke, Chris


    Almost everybody likes ice cream, so it can provide an excellent vehicle for discussing and demonstrating a variety of physical phenomena, such as Newton's law of cooling, Boyle's law and the relationship between microstructure and macroscopic properties (e.g. Young's modulus). Furthermore, a demonstration of freezing point depression can be used to make ice cream in the classroom!

  19. Ice as a Construction Material (United States)

    Zuppero, Anthony; Lewis, Joseph


    The use of ice as a construction material is discussed. A model of an ice tire torus space ship, which slowly spins to produce artificial gravity is proposed. The size of the ship, needed to support a given number of people and the required envelope mass is presented.

  20. Catalyzing Collaboration: Wisconsin's Agency-Initiated Basin Partnerships (United States)

    Genskow, Kenneth D.


    Experience with collaborative approaches to natural resource and environmental management has grown substantially over the past 20 years, and multi-interest, shared-resources initiatives have become prevalent in the United States and internationally. Although often viewed as “grass-roots” and locally initiated, governmental participants are crucial to the success of collaborative efforts, and important questions remain regarding their appropriate roles, including roles in partnership initiation. In the midst of growing governmental support for collaborative approaches in the mid-1990s, the primary natural resource and environmental management agency in Wisconsin (USA) attempted to generate a statewide system of self-sustaining, collaborative partnerships, organized around the state’s river basin boundaries. The agency expected the partnerships to enhance participation by stakeholders, leverage additional resources, and help move the agency toward more integrated and ecosystem-based resource management initiatives. Most of the basin partnerships did form and function, but ten years after this initiative, the agency has moved away from these partnerships and half have disbanded. Those that remain active have changed, but continue to work closely with agency staff. Those no longer functioning lacked clear focus, were dependent upon agency leadership, or could not overcome issues of scale. This article outlines the context for state support of collaborative initiatives and explores Wisconsin’s experience with basin partnerships by discussing their formation and reviewing governmental roles in partnerships’ emergence and change. Wisconsin’s experience suggests benefits from agency support and agency responsiveness to partnership opportunities, but cautions about expectations for initiating general-purpose partnerships.