WorldWideScience

Sample records for surface temperature based

  1. Evaluation of Surface Fatigue Strength Based on Surface Temperature

    Science.gov (United States)

    Deng, Gang; Nakanishi, Tsutomu

    Surface temperature is considered to be an integrated index that is dependent on not only the load and the dimensions at the contact point but also the sliding velocity, rolling velocity, surface roughness, and lubrication conditions. Therefore, the surface durability of rollers and gears can be evaluated more exactly and simply by the use of surface temperature rather than Hertzian stress. In this research, surface temperatures of rollers under different rolling and sliding conditions are measured using a thermocouple. The effects of load P, mean velocity Vm and sliding velocity Vs on surface temperature are clarified. An experimental formula, which expresses the linear relationship between surface temperature and the P0.86Vs1.31Vm-0.83 value, is used to determine surface temperature. By comparing calculated and measured temperature on the tooth surface of a gear, this formula is confirmed to be applicable for gear tooth surface temperature calculation.

  2. A physically based model of global freshwater surface temperature

    Science.gov (United States)

    van Beek, Ludovicus P. H.; Eikelboom, Tessa; van Vliet, Michelle T. H.; Bierkens, Marc F. P.

    2012-09-01

    Temperature determines a range of physical properties of water and exerts a strong control on surface water biogeochemistry. Thus, in freshwater ecosystems the thermal regime directly affects the geographical distribution of aquatic species through their growth and metabolism and indirectly through their tolerance to parasites and diseases. Models used to predict surface water temperature range between physically based deterministic models and statistical approaches. Here we present the initial results of a physically based deterministic model of global freshwater surface temperature. The model adds a surface water energy balance to river discharge modeled by the global hydrological model PCR-GLOBWB. In addition to advection of energy from direct precipitation, runoff, and lateral exchange along the drainage network, energy is exchanged between the water body and the atmosphere by shortwave and longwave radiation and sensible and latent heat fluxes. Also included are ice formation and its effect on heat storage and river hydraulics. We use the coupled surface water and energy balance model to simulate global freshwater surface temperature at daily time steps with a spatial resolution of 0.5° on a regular grid for the period 1976-2000. We opt to parameterize the model with globally available data and apply it without calibration in order to preserve its physical basis with the outlook of evaluating the effects of atmospheric warming on freshwater surface temperature. We validate our simulation results with daily temperature data from rivers and lakes (U.S. Geological Survey (USGS), limited to the USA) and compare mean monthly temperatures with those recorded in the Global Environment Monitoring System (GEMS) data set. Results show that the model is able to capture the mean monthly surface temperature for the majority of the GEMS stations, while the interannual variability as derived from the USGS and NOAA data was captured reasonably well. Results are poorest for

  3. Fiber-Optic Surface Temperature Sensor Based on Modal Interference

    Directory of Open Access Journals (Sweden)

    Frédéric Musin

    2016-07-01

    Full Text Available Spatially-integrated surface temperature sensing is highly useful when it comes to controlling processes, detecting hazardous conditions or monitoring the health and safety of equipment and people. Fiber-optic sensing based on modal interference has shown great sensitivity to temperature variation, by means of cost-effective image-processing of few-mode interference patterns. New developments in the field of sensor configuration, as described in this paper, include an innovative cooling and heating phase discrimination functionality and more precise measurements, based entirely on the image processing of interference patterns. The proposed technique was applied to the measurement of the integrated surface temperature of a hollow cylinder and compared with a conventional measurement system, consisting of an infrared camera and precision temperature probe. As a result, the optical technique is in line with the reference system. Compared with conventional surface temperature probes, the optical technique has the following advantages: low heat capacity temperature measurement errors, easier spatial deployment, and replacement of multiple angle infrared camera shooting and the continuous monitoring of surfaces that are not visually accessible.

  4. A Microring Temperature Sensor Based on the Surface Plasmon Wave

    Directory of Open Access Journals (Sweden)

    Wenchao Li

    2015-01-01

    Full Text Available A structure of microring sensor suitable for temperature measurement based on the surface plasmon wave is put forward in this paper. The sensor uses surface plasmon multilayer waveguiding structure in the vertical direction and U-shaped microring structure in the horizontal direction and utilizes SOI as the thermal material. The transfer function derivation of the structure of surface plasmon microring sensor is according to the transfer matrix method. While the change of refractive index of Si is caused by the change of ambient temperature, the effective refractive index of the multilayer waveguiding structure is changed, resulting in the drifting of the sensor output spectrum. This paper focuses on the transmission characteristics of multilayer waveguide structure and the impact on the output spectrum caused by refractive index changes in temperature parts. According to the calculation and simulation, the transmission performance of the structure is stable and the sensitivity is good. The resonance wavelength shift can reach 0.007 μm when the temperature is increased by 100 k and FSR can reach about 60 nm. This structure achieves a high sensitivity in the temperature sense taking into account a wide range of filter frequency selections, providing a theoretical basis for the preparation of microoptics.

  5. Modeling Apple Surface Temperature Dynamics Based on Weather Data

    Directory of Open Access Journals (Sweden)

    Lei Li

    2014-10-01

    Full Text Available The exposure of fruit surfaces to direct sunlight during the summer months can result in sunburn damage. Losses due to sunburn damage are a major economic problem when marketing fresh apples. The objective of this study was to develop and validate a model for simulating fruit surface temperature (FST dynamics based on energy balance and measured weather data. A series of weather data (air temperature, humidity, solar radiation, and wind speed was recorded for seven hours between 11:00–18:00 for two months at fifteen minute intervals. To validate the model, the FSTs of “Fuji” apples were monitored using an infrared camera in a natural orchard environment. The FST dynamics were measured using a series of thermal images. For the apples that were completely exposed to the sun, the RMSE of the model for estimating FST was less than 2.0 °C. A sensitivity analysis of the emissivity of the apple surface and the conductance of the fruit surface to water vapour showed that accurate estimations of the apple surface emissivity were important for the model. The validation results showed that the model was capable of accurately describing the thermal performances of apples under different solar radiation intensities. Thus, this model could be used to more accurately estimate the FST relative to estimates that only consider the air temperature. In addition, this model provides useful information for sunburn protection management.

  6. Modeling apple surface temperature dynamics based on weather data.

    Science.gov (United States)

    Li, Lei; Peters, Troy; Zhang, Qin; Zhang, Jingjin; Huang, Danfeng

    2014-10-27

    The exposure of fruit surfaces to direct sunlight during the summer months can result in sunburn damage. Losses due to sunburn damage are a major economic problem when marketing fresh apples. The objective of this study was to develop and validate a model for simulating fruit surface temperature (FST) dynamics based on energy balance and measured weather data. A series of weather data (air temperature, humidity, solar radiation, and wind speed) was recorded for seven hours between 11:00-18:00 for two months at fifteen minute intervals. To validate the model, the FSTs of "Fuji" apples were monitored using an infrared camera in a natural orchard environment. The FST dynamics were measured using a series of thermal images. For the apples that were completely exposed to the sun, the RMSE of the model for estimating FST was less than 2.0 °C. A sensitivity analysis of the emissivity of the apple surface and the conductance of the fruit surface to water vapour showed that accurate estimations of the apple surface emissivity were important for the model. The validation results showed that the model was capable of accurately describing the thermal performances of apples under different solar radiation intensities. Thus, this model could be used to more accurately estimate the FST relative to estimates that only consider the air temperature. In addition, this model provides useful information for sunburn protection management.

  7. SiGe Based Low Temperature Electronics for Lunar Surface Applications

    Science.gov (United States)

    Mojarradi, Mohammad M.; Kolawa, Elizabeth; Blalock, Benjamin; Cressler, John

    2012-01-01

    The temperature at the permanently shadowed regions of the moon's surface is approximately -240 C. Other areas of the lunar surface experience temperatures that vary between 120 C and -180 C during the day and night respectively. To protect against the large temperature variations of the moon surface, traditional electronics used in lunar robotics systems are placed inside a thermally controlled housing which is bulky, consumes power and adds complexity to the integration and test. SiGe Based electronics have the capability to operate over wide temperature range like that of the lunar surface. Deploying low temperature SiGe electronics in a lander platform can minimize the need for the central thermal protection system and enable the development of a new generation of landers and mobility platforms with highly efficient distributed architecture. For the past five years a team consisting of NASA, university and industry researchers has been examining the low temperature and wide temperature characteristic of SiGe based transistors for developing electronics for wide temperature needs of NASA environments such as the Moon, Titan, Mars and Europa. This presentation reports on the status of the development of wide temperature SiGe based electronics for the landers and lunar surface mobility systems.

  8. Ground-based thermal imaging of stream surface temperatures: Technique and evaluation

    Science.gov (United States)

    Bonar, Scott A.; Petre, Sally J.

    2015-01-01

    We evaluated a ground-based handheld thermal imaging system for measuring water temperatures using data from eight southwestern USA streams and rivers. We found handheld thermal imagers could provide considerably more spatial information on water temperature (for our unit one image = 19,600 individual temperature measurements) than traditional methods could supply without a prohibitive amount of effort. Furthermore, they could provide measurements of stream surface temperature almost instantaneously compared with most traditional handheld thermometers (e.g., >20 s/reading). Spatial temperature analysis is important for measurement of subtle temperature differences across waterways, and identification of warm and cold groundwater inputs. Handheld thermal imaging is less expensive and equipment intensive than airborne thermal imaging methods and is useful under riparian canopies. Disadvantages of handheld thermal imagers include their current higher expense than thermometers, their susceptibility to interference when used incorrectly, and their slightly lower accuracy than traditional temperature measurement methods. Thermal imagers can only measure surface temperature, but this usually corresponds to subsurface temperatures in well-mixed streams and rivers. Using thermal imaging in select applications, such as where spatial investigations of water temperature are needed, or in conjunction with stationary temperature data loggers or handheld electronic or liquid-in-glass thermometers to characterize stream temperatures by both time and space, could provide valuable information on stream temperature dynamics. These tools will become increasingly important to fisheries biologists as costs continue to decline.

  9. [A method of temperature measurement for hot forging with surface oxide based on infrared spectroscopy].

    Science.gov (United States)

    Zhang, Yu-cun; Qi, Yan-de; Fu, Xian-bin

    2012-05-01

    High temperature large forging is covered with a thick oxide during forging. It leads to a big measurement data error. In this paper, a method of measuring temperature based on infrared spectroscopy is presented. It can effectively eliminate the influence of surface oxide on the measurement of temperature. The method can measure the surface temperature and emissivity of the oxide directly using the infrared spectrum. The infrared spectrum is radiated from surface oxide of forging. Then it can derive the real temperature of hot forging covered with the oxide using the heat exchange equation. In order to greatly restrain interference spectroscopy through included in the received infrared radiation spectrum, three interference filter system was proposed, and a group of optimal gap parameter values using spectral simulation were obtained. The precision of temperature measurement was improved. The experimental results show that the method can accurately measure the surface temperature of high temperature forging covered with oxide. It meets the requirements of measurement accuracy, and the temperature measurement method is feasible according to the experiment result.

  10. Surface Temperature Data Analysis

    Science.gov (United States)

    Hansen, James; Ruedy, Reto

    2012-01-01

    Small global mean temperature changes may have significant to disastrous consequences for the Earth's climate if they persist for an extended period. Obtaining global means from local weather reports is hampered by the uneven spatial distribution of the reliably reporting weather stations. Methods had to be developed that minimize as far as possible the impact of that situation. This software is a method of combining temperature data of individual stations to obtain a global mean trend, overcoming/estimating the uncertainty introduced by the spatial and temporal gaps in the available data. Useful estimates were obtained by the introduction of a special grid, subdividing the Earth's surface into 8,000 equal-area boxes, using the existing data to create virtual stations at the center of each of these boxes, and combining temperature anomalies (after assessing the radius of high correlation) rather than temperatures.

  11. Effect of temperature on the acid-base properties of the alumina surface: microcalorimetry and acid-base titration experiments.

    Science.gov (United States)

    Morel, Jean-Pierre; Marmier, Nicolas; Hurel, Charlotte; Morel-Desrosiers, Nicole

    2006-06-15

    Sorption reactions on natural or synthetic materials that can attenuate the migration of pollutants in the geosphere could be affected by temperature variations. Nevertheless, most of the theoretical models describing sorption reactions are at 25 degrees C. To check these models at different temperatures, experimental data such as the enthalpies of sorption are thus required. Highly sensitive microcalorimeters can now be used to determine the heat effects accompanying the sorption of radionuclides on oxide-water interfaces, but enthalpies of sorption cannot be extracted from microcalorimetric data without a clear knowledge of the thermodynamics of protonation and deprotonation of the oxide surface. However, the values reported in the literature show large discrepancies and one must conclude that, amazingly, this fundamental problem of proton binding is not yet resolved. We have thus undertaken to measure by titration microcalorimetry the heat effects accompanying proton exchange at the alumina-water interface at 25 degrees C. Based on (i) the surface sites speciation provided by a surface complexation model (built from acid-base titrations at 25 degrees C) and (ii) results of the microcalorimetric experiments, calculations have been made to extract the enthalpic variations associated respectively to first and second deprotonation of the alumina surface. Values obtained are deltaH1 = 80+/-10 kJ mol(-1) and deltaH2 = 5+/-3 kJ mol(-1). In a second step, these enthalpy values were used to calculate the alumina surface acidity constants at 50 degrees C via the van't Hoff equation. Then a theoretical titration curve at 50 degrees C was calculated and compared to the experimental alumina surface titration curve. Good agreement between the predicted acid-base titration curve and the experimental one was observed.

  12. Impacts of land cover transitions on surface temperature in China based on satellite observations

    Science.gov (United States)

    Zhang, Yuzhen; Liang, Shunlin

    2018-02-01

    China has experienced intense land use and land cover changes during the past several decades, which have exerted significant influences on climate change. Previous studies exploring related climatic effects have focused mainly on one or two specific land use changes, or have considered all land use and land cover change types together without distinguishing their individual impacts, and few have examined the physical processes of the mechanism through which land use changes affect surface temperature. However, in this study, we considered satellite-derived data of multiple land cover changes and transitions in China. The objective was to obtain observational evidence of the climatic effects of land cover transitions in China by exploring how they affect surface temperature and to what degree they influence it through the modification of biophysical processes, with an emphasis on changes in surface albedo and evapotranspiration (ET). To achieve this goal, we quantified the changes in albedo, ET, and surface temperature in the transition areas, examined their correlations with temperature change, and calculated the contributions of different land use transitions to surface temperature change via changes in albedo and ET. Results suggested that land cover transitions from cropland to urban land increased land surface temperature (LST) during both daytime and nighttime by 0.18 and 0.01 K, respectively. Conversely, the transition of forest to cropland tended to decrease surface temperature by 0.53 K during the day and by 0.07 K at night, mainly through changes in surface albedo. Decreases in both daytime and nighttime LST were observed over regions of grassland to forest transition, corresponding to average values of 0.44 and 0.20 K, respectively, predominantly controlled by changes in ET. These results highlight the necessity to consider the individual climatic effects of different land cover transitions or conversions in climate research studies. This short

  13. A Study of Land Surface Temperature Retrieval and Thermal Environment Distribution Based on Landsat-8 in Jinan City

    Science.gov (United States)

    Dong, Fang; Chen, Jian; Yang, Fan

    2018-01-01

    Based on the medium resolution Landsat 8 OLI/TIRS, the temperature distribution in four seasons of urban area in Jinan City was obtained by using atmospheric correction method for the retrieval of land surface temperature. Quantitative analysis of the spatio-temporal distribution characteristics, development trend of urban thermal environment, the seasonal variation and the relationship between surface temperature and normalized difference vegetation index (NDVI) was studied. The results show that the distribution of high temperature areas is concentrated in Jinan, and there is a tendency to expand from east to west, revealing a negative correlation between land surface temperature distribution and NDVI. So as to provide theoretical references and scientific basis of improving the ecological environment of Jinan City, strengthening scientific planning and making overall plan addressing climate change.

  14. A physics-based algorithm for retrieving land-surface emissivity and temperature from EOS/MODIS data

    International Nuclear Information System (INIS)

    Wan, Z.; Li, Z.L.

    1997-01-01

    The authors have developed a physics-based land-surface temperature (LST) algorithm for simultaneously retrieving surface band-averaged emissivities and temperatures from day/night pairs of MODIS (Moderate Resolution Imaging Spectroradiometer) data in seven thermal infrared bands. The set of 14 nonlinear equations in the algorithm is solved with the statistical regression method and the least-squares fit method. This new LST algorithm was tested with simulated MODIS data for 80 sets of band-averaged emissivities calculated from published spectral data of terrestrial materials in wide ranges of atmospheric and surface temperature conditions. Comprehensive sensitivity and error analysis has been made to evaluate the performance of the new LST algorithm and its dependence on variations in surface emissivity and temperature, upon atmospheric conditions, as well as the noise-equivalent temperature difference (NEΔT) and calibration accuracy specifications of the MODIS instrument. In cases with a systematic calibration error of 0.5%, the standard deviations of errors in retrieved surface daytime and nighttime temperatures fall between 0.4--0.5 K over a wide range of surface temperatures for mid-latitude summer conditions. The standard deviations of errors in retrieved emissivities in bands 31 and 32 (in the 10--12.5 microm IR spectral window region) are 0.009, and the maximum error in retrieved LST values falls between 2--3 K

  15. Development of MODIS data-based algorithm for retrieving sea surface temperature in coastal waters.

    Science.gov (United States)

    Wang, Jiao; Deng, Zhiqiang

    2017-06-01

    A new algorithm was developed for retrieving sea surface temperature (SST) in coastal waters using satellite remote sensing data from Moderate Resolution Imaging Spectroradiometer (MODIS) aboard Aqua platform. The new SST algorithm was trained using the Artificial Neural Network (ANN) method and tested using 8 years of remote sensing data from MODIS Aqua sensor and in situ sensing data from the US coastal waters in Louisiana, Texas, Florida, California, and New Jersey. The ANN algorithm could be utilized to map SST in both deep offshore and particularly shallow nearshore waters at the high spatial resolution of 1 km, greatly expanding the coverage of remote sensing-based SST data from offshore waters to nearshore waters. Applications of the ANN algorithm require only the remotely sensed reflectance values from the two MODIS Aqua thermal bands 31 and 32 as input data. Application results indicated that the ANN algorithm was able to explaining 82-90% variations in observed SST in US coastal waters. While the algorithm is generally applicable to the retrieval of SST, it works best for nearshore waters where important coastal resources are located and existing algorithms are either not applicable or do not work well, making the new ANN-based SST algorithm unique and particularly useful to coastal resource management.

  16. Downscaling of Aircraft, Landsat, and MODIS-bases Land Surface Temperature Images with Support Vector Machines

    Science.gov (United States)

    High spatial resolution Land Surface Temperature (LST) images are required to estimate evapotranspiration (ET) at a field scale for irrigation scheduling purposes. Satellite sensors such as Landsat 5 Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) can offer images at s...

  17. Seasonal lake surface water temperature trends reflected by heterocyst glycolipid-based molecular thermometers

    Science.gov (United States)

    Bauersachs, T.; Rochelmeier, J.; Schwark, L.

    2015-06-01

    It has been demonstrated that the relative distribution of heterocyst glycolipids (HGs) in cultures of N2-fixing heterocystous cyanobacteria is largely controlled by growth temperature, suggesting a potential use of these components in paleoenvironmental studies. Here, we investigated the effect of environmental parameters (e.g., surface water temperatures, oxygen concentrations and pH) on the distribution of HGs in a natural system using water column filtrates collected from Lake Schreventeich (Kiel, Germany) from late July to the end of October 2013. HPLC-ESI/MS (high-performance liquid chromatography coupled to electrospray ionization-mass spectrometry) analysis revealed a dominance of 1-(O-hexose)-3,25-hexacosanediols (HG26 diols) and 1-(O-hexose)-3-keto-25-hexacosanol (HG26 keto-ol) in the solvent-extracted water column filtrates, which were accompanied by minor abundances of 1-(O-hexose)-3,27-octacosanediol (HG28 diol) and 1-(O-hexose)-3-keto-27-octacosanol (HG28 keto-ol) as well as 1-(O-hexose)-3,25,27-octacosanetriol (HG28 triol) and 1-(O-hexose)-3-keto-25,27-octacosanediol (HG28 keto-diol). Fractional abundances of alcoholic and ketonic HGs generally showed strong linear correlations with surface water temperatures and no or only weak linear correlations with both oxygen concentrations and pH. Changes in the distribution of the most abundant diol and keto-ol (e.g., HG26 diol and HG26 keto-ol) were quantitatively expressed as the HDI26 (heterocyst diol index of 26 carbon atoms) with values of this index ranging from 0.89 in mid-August to 0.66 in mid-October. An average HDI26 value of 0.79, which translates into a calculated surface water temperature of 15.8 ± 0.3 °C, was obtained from surface sediments collected from Lake Schreventeich. This temperature - and temperatures obtained from other HG indices (e.g., HDI28 and HTI28) - is similar to the one measured during maximum cyanobacterial productivity in early to mid-September and suggests that HGs

  18. Estimation of Daily Air Temperature Based on MODIS Land Surface Temperature Products over the Corn Belt in the US

    Directory of Open Access Journals (Sweden)

    Linglin Zeng

    2015-01-01

    Full Text Available Air temperature (Ta is a key input in a wide range of agroclimatic applications. Moderate Resolution Imaging Spectroradiometer (MODIS Ts (Land Surface Temperature (LST products are widely used to estimate daily Ta. However, only daytime LST (Ts-day or nighttime LST (Ts-night data have been used to estimate Tmax/Tmin (daily maximum or minimum air temperature, respectively. The relationship between Tmax and Ts-night, and the one between Tmin and Ts-day has not been studied. In this study, both the ability of Ts-night data to estimate Tmax and the ability of Ts-day data to estimate Tmin were tested and studied in the Corn Belt during the growing season (May–September from 2008 to 2012, using MODIS daily LST products from both Terra and Aqua. The results show that using Ts-night for estimating Tmax could result in a higher accuracy than using Ts-day for a similar estimate. Combining Ts-day and Ts-night, the estimation of Tmax was improved by 0.19–1.85, 0.37–1.12 and 0.26–0.93 °C for crops, deciduous forest and developed areas, respectively, when compared with using only Ts-day or Ts-night data. The main factors influencing the Ta estimation errors spatially and temporally were analyzed and discussed, such as satellite overpassing time, air masses, irrigation, etc.

  19. Estimation of land surface temperature based on satellite image data. Paper no. IGEC-1-117

    International Nuclear Information System (INIS)

    Torii, S.; Yano, T.; Iino, N.

    2005-01-01

    The aim of the present study is to predict a ground surface temperature (GST) of Kagoshima Prefecture in Kyushu Island, Japan, by using LANDSAT-5/TM and NOAA-11/AVHRR digital data. Image processing procedure is employed to aid in evaluating GST, in which the thermal images of AVHRR bands 4 and 5 are analysed. Emphasis is placed on the prediction accuracy of the existing atmospheric correlation equations taking the atmospheric attenuation effect into account, which are proposed by Tamba et. al., Bates and Diaz, and Sakkaida and Kawamura. It is disclosed that (I) the factor of the zenith angle need to be taken into account when the accurate GST is evaluated by using the atmospheric correction equations, (ii) that of Sakaida and Kawamura has better accuracy, (iii) LANDSAT-5/TM data contains a very high resolution level of the land, the estimated land surface temperature is higher than the measured value, and (iv) improved accuracy of the surface temperature is achieved if LANDSAT-5/TM data are used together with NOAA-11/AVHRR. (author)

  20. The investigation of spatiotemporal variations of land surface temperature based on land use changes using NDVI in southwest of Iran

    Science.gov (United States)

    Fathizad, Hassan; Tazeh, Mahdi; Kalantari, Saeideh; Shojaei, Saeed

    2017-10-01

    Land use changes can bring about changes in land surface temperature (LST) which is influenced by climatic conditions and physical characteristics of the land surface. In this study, spatiotemporal variations of land surface temperature have been investigated in the desert area of Dasht-e-Abbas, Ilam, based on a variety of land use changes. The investigated periods for the study include 1990, 2000 and 2010 using Landsat image data. First, in mapping land use we used the Fuzzy ARTMAP Neural Network Classification method followed by determination of the NDVI Index to estimate land surface temperature. The results show an increase in LST in areas where degradation, land use and land cover changes have occurred. In 1990, 2000 and 2010, the average land surface temperature of the Fair Rangelands was 26.72 °C, 30.06 °C and 30.95 °C, respectively. This rangeland has been reduced by about 5%. For poor rangelands, the average LSTs were 26.95, 32.83 and 34.49 Cº, respectively which had a 18% reduction. In 1990, 2000 and 2010, the average land surface temperatures of agricultural lands were 24.31 °C, 27.87 °C and 28.61 °C, respectively which has been an increasing trend. The reason can be attributed to changes in cropping patterns of the study area.

  1. Response surface and neural network based predictive models of cutting temperature in hard turning

    Directory of Open Access Journals (Sweden)

    Mozammel Mia

    2016-11-01

    Full Text Available The present study aimed to develop the predictive models of average tool-workpiece interface temperature in hard turning of AISI 1060 steels by coated carbide insert. The Response Surface Methodology (RSM and Artificial Neural Network (ANN were employed to predict the temperature in respect of cutting speed, feed rate and material hardness. The number and orientation of the experimental trials, conducted in both dry and high pressure coolant (HPC environments, were planned using full factorial design. The temperature was measured by using the tool-work thermocouple. In RSM model, two quadratic equations of temperature were derived from experimental data. The analysis of variance (ANOVA and mean absolute percentage error (MAPE were performed to suffice the adequacy of the models. In ANN model, 80% data were used to train and 20% data were employed for testing. Like RSM, herein, the error analysis was also conducted. The accuracy of the RSM and ANN model was found to be ⩾99%. The ANN models exhibit an error of ∼5% MAE for testing data. The regression coefficient was found to be greater than 99.9% for both dry and HPC. Both these models are acceptable, although the ANN model demonstrated a higher accuracy. These models, if employed, are expected to provide a better control of cutting temperature in turning of hardened steel.

  2. Fatigue crack growth from handling surface anomalies in a nickel based superalloy at high temperature

    Directory of Open Access Journals (Sweden)

    Gourdin Stéphane

    2014-01-01

    Full Text Available Aircraft engine manufacturers have to demonstrate that handling surface anomalies in sensitive areas of discs are not critical for in-service life of a component. Currently, the models used consider anomalies as long cracks propagating from the first cycle, which introduces a certain degree of conservatism when calculating the fatigue life of surface flaws. Preliminary studies have shown that the first stages of crack propagation from surface anomalies are responsible for the conservative results. Thus, the aim of the study is to characterize the crack propagation from typical surface anomalies and to establish a new crack growth model, which can account for the micro-propagation stage. To separate the effects of the geometry of the anomalies and the residual stress state after introduction of the surface flaws, two V-type anomalies are studied: scratches and dents. Different studies have shown that the residual stresses beneath the anomalies seem to control the fatigue life of samples exhibiting scratches and dents. In order to monitor the crack micro-propagation, a direct current potential drop technique, coupled with heat tints is used during fatigue tests at elevated temperature. Thermal treatments releasing the residual stresses are also used to decouple the effect of crack morphology and residual stresses.

  3. Surface chemistry, microstructure and friction properties of some ferrous-base metallic glasses at temperatures to 750 C

    Science.gov (United States)

    Miyoshi, K.; Buckley, D. H.

    1982-01-01

    X-ray photoelectron spectroscopy analysis, transmission electron microscopy, diffraction studies, and sliding friction experiments were conducted with ferrous-base metallic glasses in sliding contact with aluminum oxide at temperatures from room to 750 C in a vacuum of 30 nPa. The results indicate that there is a significant temperature influence on the friction properties, surface chemistry, and microstructure of metallic glasses. The relative concentrations of the various constituents at the surface of the sputtered specimens were very different from the normal bulk compositions. Contaminants can come from the bulk of the material to the surface upon heating and impart boric oxide and silicon oxide at 350 C and boron nitride above 500 C. The coefficient of friction increased with increasing temperature to 350 C. Above 500 C the coefficient of friction decreased rapidly. The segregation of contaminants may be responsible for the friction behavior.

  4. GISS Surface Temperature Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GISTEMP dataset is a global 2x2 gridded temperature anomaly dataset. Temperature data is updated around the middle of every month using current data files from...

  5. The prediction of surface temperature in the new seasonal prediction system based on the MPI-ESM coupled climate model

    Science.gov (United States)

    Baehr, J.; Fröhlich, K.; Botzet, M.; Domeisen, D. I. V.; Kornblueh, L.; Notz, D.; Piontek, R.; Pohlmann, H.; Tietsche, S.; Müller, W. A.

    2015-05-01

    A seasonal forecast system is presented, based on the global coupled climate model MPI-ESM as used for CMIP5 simulations. We describe the initialisation of the system and analyse its predictive skill for surface temperature. The presented system is initialised in the atmospheric, oceanic, and sea ice component of the model from reanalysis/observations with full field nudging in all three components. For the initialisation of the ensemble, bred vectors with a vertically varying norm are implemented in the ocean component to generate initial perturbations. In a set of ensemble hindcast simulations, starting each May and November between 1982 and 2010, we analyse the predictive skill. Bias-corrected ensemble forecasts for each start date reproduce the observed surface temperature anomalies at 2-4 months lead time, particularly in the tropics. Niño3.4 sea surface temperature anomalies show a small root-mean-square error and predictive skill up to 6 months. Away from the tropics, predictive skill is mostly limited to the ocean, and to regions which are strongly influenced by ENSO teleconnections. In summary, the presented seasonal prediction system based on a coupled climate model shows predictive skill for surface temperature at seasonal time scales comparable to other seasonal prediction systems using different underlying models and initialisation strategies. As the same model underlying our seasonal prediction system—with a different initialisation—is presently also used for decadal predictions, this is an important step towards seamless seasonal-to-decadal climate predictions.

  6. Land Surface Temperature Differences within Local Climate Zones, Based on Two Central European Cities

    Czech Academy of Sciences Publication Activity Database

    Geletič, Jan; Lehnert, M.; Dobrovolný, Petr

    2016-01-01

    Roč. 8, č. 10 (2016), č. článku 788. ISSN 2072-4292 R&D Projects: GA MŠk(CZ) LO1415 Grant - others:UrbanAdapt(XE) EHP-CZ02-OV-1-036-2015 Program:CZ02 Biodiverzita a ekosystémové služby / Monitorování a integrované plánování a kontrola v životním prostředí/ Adaptace na změnu klimatu Institutional support: RVO:67179843 Keywords : land surface temperature * local climate zones * ASTER * LANDSAT * analysis of variance * Prague * Brno * Czech Republic Subject RIV: EH - Ecology, Behaviour Impact factor: 3.244, year: 2016

  7. Land surface temperature distribution and development for green open space in Medan city using imagery-based satellite Landsat 8

    Science.gov (United States)

    Sulistiyono, N.; Basyuni, M.; Slamet, B.

    2018-03-01

    Green open space (GOS) is one of the requirements where a city is comfortable to stay. GOS might reduce land surface temperature (LST) and air pollution. Medan is one of the biggest towns in Indonesia that experienced rapid development. However, the early development tends to neglect the GOS existence for the city. The objective of the study is to determine the distribution of land surface temperature and the relationship between the normalized difference vegetation index (NDVI) and the priority of GOS development in Medan City using imagery-based satellite Landsat 8. The method approached to correlate the distribution of land surface temperature derived from the value of digital number band 10 with the NDVI which was from the ratio of groups five and four on satellite images of Landsat 8. The results showed that the distribution of land surface temperature in the Medan City in 2016 ranged 20.57 - 33.83 °C. The relationship between the distribution of LST distribution with NDVI was reversed with a negative correlation of -0.543 (sig 0,000). The direction of GOS in Medan City is therefore developed on the allocation of LST and divided into three priority classes namely first priority class had 5,119.71 ha, the second priority consisted of 16,935.76 ha, and third priority of 6,118.50 ha.

  8. Effects of prior surface damage on high-temperature oxidation of Fe-, Ni-, and Co-based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL; Lowe, Tracie M [ORNL; Pint, Bruce A [ORNL

    2009-01-01

    Multi-component metallic alloys have been developed to withstand high-temperature service in corrosive environments. Some of these applications, like exhaust valve seats in internal combustion engines, must also resist sliding, impact, and abrasion. The conjoint effects of temperature, oxidation, and mechanical contact can result in accelerated wear and the formation of complex surface layers whose properties differ from those of the base metal and the oxide scale that forms in the absence of mechanical contact. The authors have investigated the effects of prior surface damage, produced by scratch tests, on the localized reformation of oxide layers. Three high-performance commercial alloys, based on iron, nickel, and cobalt, were used as model materials. Thermogravimetric analysis (TGA) was used to determine their static oxidation rates at elevated temperature (850o C). A micro-abrasion, ball-cratering technique was used to measure oxide layer thickness and to compare it with TGA results. By using taper-sectioning techniques and energy-dispersive elemental mapping, a comparison was made between oxide compositions grown on non-damaged surfaces and oxides that formed on grooves produced by a diamond stylus. Microindentation and scratch hardness data revealed the effects of high temperature exposure on both the substrate hardness and the nature of oxide scale disruption. There were significant differences in elemental distribution between statically-formed oxides and those that formed on scratched regions

  9. Temperature dependence of surface nanobubbles

    NARCIS (Netherlands)

    Berkelaar, R.P.; Seddon, James Richard Thorley; Zandvliet, Henricus J.W.; Lohse, Detlef

    2012-01-01

    The temperature dependence of nanobubbles was investigated experimentally using atomic force microscopy. By scanning the same area of the surface at temperatures from 51 °C to 25 °C it was possible to track geometrical changes of individual nanobubbles as the temperature was decreased.

  10. Reconstruction of Daily Sea Surface Temperature Based on Radial Basis Function Networks

    Directory of Open Access Journals (Sweden)

    Zhihong Liao

    2017-11-01

    Full Text Available A radial basis function network (RBFN method is proposed to reconstruct daily Sea surface temperatures (SSTs with limited SST samples. For the purpose of evaluating the SSTs using this method, non-biased SST samples in the Pacific Ocean (10°N–30°N, 115°E–135°E are selected when the tropical storm Hagibis arrived in June 2014, and these SST samples are obtained from the Reynolds optimum interpolation (OI v2 daily 0.25° SST (OISST products according to the distribution of AVHRR L2p SST and in-situ SST data. Furthermore, an improved nearest neighbor cluster (INNC algorithm is designed to search for the optimal hidden knots for RBFNs from both the SST samples and the background fields. Then, the reconstructed SSTs from the RBFN method are compared with the results from the OI method. The statistical results show that the RBFN method has a better performance of reconstructing SST than the OI method in the study, and that the average RMSE is 0.48 °C for the RBFN method, which is quite smaller than the value of 0.69 °C for the OI method. Additionally, the RBFN methods with different basis functions and clustering algorithms are tested, and we discover that the INNC algorithm with multi-quadric function is quite suitable for the RBFN method to reconstruct SSTs when the SST samples are sparsely distributed.

  11. Determination of transient temperature and heat flux on the surface of a reactor control rod based on temperature measurements at the interior points

    International Nuclear Information System (INIS)

    Cebula, Artur; Taler, Jan

    2014-01-01

    The paper presents heat transfer calculation results concerning a control rod of nuclear power plant. Apart from numerical calculation results, experimental heat transfer measurements of the control rod model are also presented. The control rod that is the object of interest is surrounded by a mixing region of hot and cold streams and, as a consequence, is subjected to thermal fluctuations. The paper describes a method based on the solution of the inverse heat conduction problem (IHCP) for determining heat flux on the outer surface of the rod. Numerical tests were conducted to validate the method by comparison of the results with the time changes of surface temperature and heat flux which were obtained from the computational fluid dynamics (CFD) simulation of the mixing process. A measuring instrument was designed to measure the heat flux at the outer surface of the control rod model. In addition, the principle of operation and construction of heat flux meter is presented in detail. -- Highlights: • Temperature and heat flux estimation during cooling of control rod are presented. • The inverse technique is based on the space marching method. • The instrument for surface heat flux measurement was manufactured and tested. • CFD simulations were used to validate the developed inverse technique. • Actual data were used to demonstrate practical applicability of the method

  12. The Interface Structure of High-Temperature Oxidation-Resistant Aluminum-Based Coatings on Titanium Billet Surface

    Science.gov (United States)

    Xu, Zhefeng; Rong, Ju; Yu, Xiaohua; Kun, Meng; Zhan, Zhaolin; Wang, Xiao; Zhang, Yannan

    2017-10-01

    A new type of high-temperature oxidation-resistant aluminum-based coating, on a titanium billet surface, was fabricated by the cold spray method, at a high temperature of 1050°C, for 8 h, under atmospheric pressure. The microstructure of the exposed surface was analyzed via optical microscopy, the microstructure of the coating and elemental diffusion was analyzed via field emission scanning electron microscopy, and the interfacial phases were identified via x-ray diffraction. The Ti-Al binary phase diagram and Gibbs free energy of the stable phase were calculated by Thermo-calc. The results revealed that good oxidation resistant 50-μm-thick coatings were successfully obtained after 8 h at 1050°C. Two layers were obtained after the coating process: an Al2O3 oxidation layer and a TiAl3 transition layer on the Ti-based substrate. The large and brittle Al2O3 grains on the surface, which can be easily spalled off from the surface after thermal processing, protected the substrate against oxidation during processing. In addition, the thermodynamic calculation results were in good agreement with the experimental data.

  13. Modeling of mean radiant temperature based on comparison of airborne remote sensing data with surface measured data

    Science.gov (United States)

    Chen, Yu-Cheng; Chen, Chih-Yu; Matzarakis, Andreas; Liu, Jin-King; Lin, Tzu-Ping

    2016-06-01

    Assessment of outdoor thermal comfort is becoming increasingly important due to the urban heat island effect, which strongly affects the urban thermal environment. The mean radiant temperature (Tmrt) quantifies the effect of the radiation environment on humans, but it can only be estimated based on influencing parameters and factors. Knowledge of Tmrt is important for quantifying the heat load on human beings, especially during heat waves. This study estimates Tmrt using several methods, which are based on climatic data from a traditional weather station, microscale ground surface measurements, land surface temperature (LST) and light detection and ranging (LIDAR) data measured using airborne devices. Analytical results reveal that the best means of estimating Tmrt combines information about LST and surface elevation information with meteorological data from the closest weather station. The application in this method can eliminate the inconvenience of executing a wide range ground surface measurement, the insufficient resolution of satellite data and the incomplete data of current urban built environments. This method can be used to map a whole city to identify hot spots, and can be contributed to understanding human biometeorological conditions quickly and accurately.

  14. ISLSCP II Sea Surface Temperature

    Data.gov (United States)

    National Aeronautics and Space Administration — Sea surface temperature (SST) is an important indicator of the state of the earth climate system as well as a key variable in the coupling between the atmosphere and...

  15. Chemical etching of Tungsten thin films for high-temperature surface acoustic wave-based sensor devices

    Energy Technology Data Exchange (ETDEWEB)

    Spindler, M., E-mail: m.spindler@ifw-dresden.de [IFW Dresden, SAWLab Saxony, P.O. Box 270116, D-01171 Dresden (Germany); Herold, S.; Acker, J. [BTU Cottbus – Senftenberg, Faculty of Sciences, P.O. Box 101548, 01968 Senftenberg (Germany); Brachmann, E.; Oswald, S.; Menzel, S.; Rane, G. [IFW Dresden, SAWLab Saxony, P.O. Box 270116, D-01171 Dresden (Germany)

    2016-08-01

    Surface acoustic wave devices are widely used as wireless sensors in different application fields. Recent developments aimed to utilize those devices as temperature sensors even in the high temperature range (T > 300 °C) and in harsh environmental conditions. Therefore, conventional materials, which are used for the substrate and for the interdigital transducer finger electrodes such as multilayers or alloys based on Al or Cu have to be exchanged by materials, which fulfill some important criteria regarding temperature related effects. Electron beam evaporation as a standard fabrication method is not well applicable for depositing high temperature stable electrode materials because of their very high melting points. Magnetron sputtering is an alternative deposition process but is also not applicable for lift-off structuring without any further improvement of the structuring process. Due to a relatively high Ar gas pressure of about 10{sup −1} Pa, the sidewalls of the photoresist line structures are also covered by the metallization, which subsequently prevents a successful lift-off process. In this study, we investigate the chemical etching of thin tungsten films as an intermediate step between magnetron sputtering deposition of thin tungsten finger electrodes and the lift-off process to remove sidewall covering for a successful patterning process of interdigital transducers. - Highlights: • We fabricated Tungsten SAW Electrodes by magnetron sputtering technology. • An etching process removes sidewall covering of photoresist, which allows lift-off. • Tungsten etching rates based on a hydrogen peroxide solutions were determined.

  16. The effects of temperature and alkyl chain length on the density and surface tension of the imidazolium-based geminal dicationic ionic liquids

    International Nuclear Information System (INIS)

    Moosavi, Majid; Khashei, Fatemeh; Sharifi, Ali; Mirzaei, Mojtaba

    2017-01-01

    Highlights: • Surface tension and density of three GDILs were measured at different temperatures. • Surface entropy and surface enthalpy indicate the surface ordering in these GDILs. • Parachors and critical temperatures of these systems were estimated. • Results of GDILs were compared with the results of corresponding traditional MILs. • Relations between surface tension, density and viscosity of GDILs were demonstrated. - Abstract: Surface tensions and densities of three imidazolium-based geminal dicationic ionic liquids (GDILs) with the bis(trifluoromethylsulfonyl)imide, [NTf 2 ] − , as a common anion, have been measured at ambient pressure at different temperatures in the range from 296.00 to 353.15 K. The surface thermodynamic functions such as surface entropy and surface enthalpy were derived from the temperature dependence of surface tension which indicated the surface ordering in these GDILs. As well as the parachor, the critical temperatures of these systems have been estimated using the Guggenheim and Eotvos correlations. In each case, the results of GDILs have been compared with the results of corresponding traditional monocationic ILs (MILs). Also, the relations between the surface tension and density and also surface tension and viscosity data have been demonstrated and discussed.

  17. Extreme Maximum Land Surface Temperatures.

    Science.gov (United States)

    Garratt, J. R.

    1992-09-01

    There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

  18. Mid-Pliocene to Early Pleistocene land and sea surface temperature history of NW Australia based on organic geochemical proxies

    Science.gov (United States)

    Smith, R. A.; Castañeda, I. S.; Henderiks, J.; Christensen, B. A.; De Vleeschouwer, D.; Renema, W.; Groeneveld, J.; Bogus, K.; Gallagher, S. J.; Fulthorpe, C.; Expedition 356 Scientists, I.

    2017-12-01

    IODP Expedition 356 Site U1463 is located off the coast of NW Australia, and is sensitive to Indonesian Throughflow (ITF) variability. The ITF is a critical ocean gateway that affects global thermohaline circulation, and regulates the movement of water from the Pacific Ocean into the Indian Ocean. However, despite its importance to the global climate system, few SST reconstructions exist for this region that span the Plio-Pleistocene. Here we investigate both the land and sea-surface temperature (SST) history of NW Australia to constrain ITF variability across the Plio-Pleistocene interval. We apply multiple organic geochemical proxies to this site from 3.4-2.6 Ma, which includes the mid-Pliocene warm period, characterized by slightly higher (2-3°C) global temperatures and similar CO2 concentrations to modern values (e.g. Badger et al. 2013; Bartoli et al., 2011; Dowsett et al., 2009; Hönisch et al., 2009; Pagani et al. 2009; Raymo et al., 1996). SST was reconstructed using TEX86, based on isoprenoid glycerol dialkyl glycerol tetraethers (iGDGTs), and the long-chain diol index (LDI), based on the ratio of diols produced by marine diatoms (Rampen et al., 2012). The Uk'37 index, based on long-chain ketones, was analyzed but cannot be applied as a SST proxy at this site due to the influence of coastal alkenone producers. Additionally, a continental air temperature record was developed using the MBT'5ME proxy, based on branched GDGTs (De Jonge et al., 2014; Weijers et al., 2007). We find that TEX86, LDI and MBT'5Me exhibit similar trends and show relatively warm and stable temperatures from 3.5-2.4 Ma followed by a gradual cooling of 3-4°C from 2.4-1.5 Ma. This cooling corresponds with an arid interval previously identified on the same core by Christensen et al. (2017). Furthermore, we find that the TEX86 record agrees closely with the LR04 global benthic δ18O stack (Lisiecki and Raymo, 2005) and captures glacial/interglacial periods including Marine Isotope Stage

  19. Estimation of bare soil surface temperature from air temperature and ...

    African Journals Online (AJOL)

    Soil surface temperature has critical influence on climate, agricultural and hydrological activities since it serves as a good indicator of the energy budget of the earth's surface. Two empirical models for estimating soil surface temperature from air temperature and soil depth temperature were developed. The coefficient of ...

  20. MODIS Land Surface Temperature time series reconstruction with Open Source GIS: A new quality of temperature based ecological indicators in complex terrain (Invited)

    Science.gov (United States)

    Neteler, M.

    2009-12-01

    In complex terrain like the Central European Alps, meteorological stations and ground surveys are usually sparsely and/or irregularly distributed and often favor agricultural areas. The application of traditional geospatial interpolation methods in complex terrain remains challenging and difficult to optimize. An alternative data source is remote sensing: high temporal resolution satellite data are continuously gaining interest since these data are intrinsically spatialized: continuous field of observations is obtained with this tool instead of point data. The increasing data availability suggests using these time series as surrogate to certain measures from meteorological stations, especially for temperature and related derivatives. The Terra and Aqua satellites with the Moderate Resolution Imaging Spectroradiometer (MODIS) provide four Earth coverages per day at various resolutions. We analyzed 8 years (2000 to 2008) of daily land surface temperature (LST) data from MODIS in an area located in the Southern European Alps. A method was developed to reconstruct incomplete maps (cloud coverage, invalid pixels) based on image statistics and on a model that includes additional GIS layers. The original LST map resolution of 1000m could be improved to 200m in this process which renders the resulting LST maps applicable at regional scales. We propose the use of these reconstructed daily LST time series as surrogate to meteorological observations especially in the area of epidemiological modeling where data are typically aggregated to decadal indicators. From these daily LST map series, derivable indicators include: 1) temperatures minima, means and maxima for annual/monthly/decadal periods; 2) unusual hot summers;3) the calculation of growing degree days, and 4) spring temperature increase or autumnal temperature decrease. Since more than 8 years of MODIS LST data are available today, even preliminary gradients can be extracted to assess multi-annual temperature trends

  1. Deposition temperature dependence of material and Si surface passivation properties of O3-based atomic layer deposited Al2O3-based films and stacks

    International Nuclear Information System (INIS)

    Bordihn, Stefan; Mertens, Verena; Müller, Jörg W.; Kessels, W. M. M.

    2014-01-01

    The material composition and the Si surface passivation of aluminum oxide (Al 2 O 3 ) films prepared by atomic layer deposition using Al(CH 3 ) 3 and O 3 as precursors were investigated for deposition temperatures (T Dep ) between 200 °C and 500 °C. The growth per cycle decreased with increasing deposition temperature due to a lower Al deposition rate. In contrast the material composition was hardly affected except for the hydrogen concentration, which decreased from [H] = 3 at. % at 200 °C to [H]  2 O 3 /SiN x stacks complemented the work and revealed similar levels of surface passivation as single-layer Al 2 O 3 films, both for the chemical and field-effect passivation. The fixed charge density in the Al 2 O 3 /SiN x stacks, reflecting the field-effect passivation, was reduced by one order of magnitude from 3·10 12  cm −2 to 3·10 11  cm −2 when T Dep was increased from 300 °C to 500 °C. The level of the chemical passivation changed as well, but the total level of the surface passivation was hardly affected by the value of T Dep . When firing films prepared at of low T Dep , blistering of the films occurred and this strongly reduced the surface passivation. These results presented in this work demonstrate that a high level of surface passivation can be achieved for Al 2 O 3 -based films and stacks over a wide range of conditions when the combination of deposition temperature and annealing or firing temperature is carefully chosen

  2. Infrared thermography--a non-invasive tool to evaluate thermal status of neonatal pigs based on surface temperature.

    Science.gov (United States)

    Kammersgaard, T S; Malmkvist, J; Pedersen, L J

    2013-12-01

    Hypothermia is a major cause of mortality in neonatal pigs. Infrared (IR) thermography is a promising non-invasive method to assess thermal status, but has not been evaluated for use on neonatal pigs from birth. The aim of this study was to evaluate the application of IR thermography as a non-invasive tool to estimate body temperature and assess the thermal status in newborn pigs by (1) estimating the relationship between surface temperature and rectal temperature (RT) in neonatal pigs; and (2) estimating the influence of air temperature (AT), birth weight and the time from birth on the relationship between surface temperature and RT. The method was evaluated on the basis of 1695 thermograms and 915 RTs on 91 neonatal pigs born in loose farrowing pens with floor heating at 34°C, and three different ATs (15°C, 20°C and 25°C). Full-body thermograms of the back and the side of the pigs and RT were acquired at 11 sampling times between birth and 48 h after birth. The maximum (IRmax), minimum, average of the full body and ear minimum IR surface temperatures were derived from the thermograms. IRmax had the highest correlation with RT (0.82) and was therefore used in the statistical analysis. The relation of RT by IRmax depended on time at: 0 h (slope: 0.20°C, Pmethod has the potential to be used without the need for manual restraint of the pigs. On the basis of the results of this study, we propose that IRmax temperature from full-body thermograms has implication as a valid tool to assess the thermal status in neonatal piglets but not as an identical substitute for RT.

  3. Delimitation of the warm and cold period of the year based on the variation of the Aegean sea surface temperature

    Directory of Open Access Journals (Sweden)

    A. MAVRAKIS

    2004-06-01

    Full Text Available Knowledge of the warm and cold season onset is important for the living conditions and the occupational activities of the inhabitants of a given area, and especially for agriculture and tourism. This paper presents a way to estimate the onset/end of the cold and warm period of the year, based on the sinusoidal annual variation of the Sea Surface Temperature. The method was applied on data from 8 stations of the Hellenic Navy Hydrographic Service, covering the period from 1965-1995. The results showed that the warm period starts sometime between April 28th and May 21st while it ends between October 27th and November 19th in accordance with the findings of other studies. Characteristic of the nature of the parameter used is the very low variance per station – 15 days at maximum. The average date of warm period onset is statistically the same for the largest part of the Aegean, with only one differentiation, that between Kavala and the southern stations ( Thira and Heraklion.

  4. A method for sensible heat flux model parameterization based on radiometric surface temperature and environmental factors without involving the parameter KB-1

    Science.gov (United States)

    Zhuang, Qifeng; Wu, Bingfang; Yan, Nana; Zhu, Weiwei; Xing, Qiang

    2016-05-01

    Sensible heat flux is a key component of land-atmosphere interaction. In most parameterizations it is calculated with surface-air temperature differences and total aerodynamic resistance to heat transfer (Rae) that is related to the KB-1 parameter. Suitable values are hard to obtain since KB-1 is related both to canopy characteristics and environmental conditions. In this paper, a parameterize method for sensible heat flux over vegetated surfaces (maize field and grass land in the Heihe river basin of northwest China) was proposed based on the radiometric surface temperature, surface resistance (Rs) and vapor pressures (saturated and actual) at the surface and the atmosphere above the canopy. A biophysics-based surface resistance model was revised to compute surface resistance with several environmental factors. The total aerodynamic resistance to heat transfer is directly calculated by combining the biophysics-based surface resistance and vapor pressures. One merit of this method is that the calculation of KB-1 can be avoided. The method provides a new way to estimate sensible heat flux over vegetated surfaces and its performance compares well to the LAS measured sensible heat and other empirical or semi-empirical KB-1 based estimations.

  5. The international surface temperature initiative

    Science.gov (United States)

    Thorne, P. W.; Lawrimore, J. H.; Willett, K. M.; Allan, R.; Chandler, R. E.; Mhanda, A.; de Podesta, M.; Possolo, A.; Revadekar, J.; Rusticucci, M.; Stott, P. A.; Strouse, G. F.; Trewin, B.; Wang, X. L.; Yatagai, A.; Merchant, C.; Merlone, A.; Peterson, T. C.; Scott, E. M.

    2013-09-01

    The aim of International Surface Temperature Initiative is to create an end-to-end process for analysis of air temperature data taken over the land surface of the Earth. The foundation of any analysis is the source data. Land surface air temperature records have traditionally been stored in local, organizational, national and international holdings, some of which have been available digitally but many of which are available solely on paper or as imaged files. Further, economic and geopolitical realities have often precluded open sharing of these data. The necessary first step therefore is to collate readily available holdings and augment these over time either through gaining access to previously unavailable digital data or through data rescue and digitization activities. Next, it must be recognized that these historical measurements were made primarily in support of real-time weather applications where timeliness and coverage are key. At almost every long-term station it is virtually certain that changes in instrumentation, siting or observing practices have occurred. Because none of the historical measures were made in a metrologically traceable manner there is no unambiguous way to retrieve the true climate evolution from the heterogeneous raw data holdings. Therefore it is desirable for multiple independent groups to produce adjusted data sets (so-called homogenized data) to adequately understand the data characteristics and estimate uncertainties. Then it is necessary to benchmark the performance of the contributed algorithms (equivalent to metrological software validation) through development of realistic benchmark datasets. In support of this, a series of successive benchmarking and assessment cycles are envisaged, allowing continual improvement while avoiding over-tuning of algorithms. Finally, a portal is proposed giving access to related data-products, utilizing the assessment results to provide guidance to end-users on which product is the most suited to

  6. NOAA Global Surface Temperature (NOAAGlobalTemp)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Global Surface Temperature Dataset (NOAAGlobalTemp) is a merged land–ocean surface temperature analysis (formerly known as MLOST) (link is external). It is...

  7. GODAE, SFCOBS - Surface Temperature Observations, 1998-present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GODAE, SFCOBS - Surface Temperature Observations: Ship, fixed/drifting buoy, and CMAN in-situ surface temperature. Global Telecommunication System (GTS) Data. The...

  8. Extended Reconstructed Sea Surface Temperature (ERSST)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Extended Reconstructed Sea Surface Temperature (ERSST) dataset is a global monthly sea surface temperature analysis derived from the International Comprehensive...

  9. High temperature oxidation behavior of aluminide on a Ni-based single crystal superalloy in different surface orientations

    Institute of Scientific and Technical Information of China (English)

    Fahamsyah H.Latief; Koji Kakehi; El-Sayed M.Sherif

    2014-01-01

    An investigation on oxidation behavior of coated Ni-based single crystal superalloy in different surface orientations has been carried out at 1100 1C. It has been found that the {100} surface shows a better oxidation resistance than the {110} one, which is attributed that the {110}surface had a slightly higher oxidation rate when compared to the {100} surface. The experimental results also indicated that the anisotropic oxidation behavior took place even with a very small difference in the oxidation rates that was found between the two surfaces. The differences of the topologically close packed phase amount and its penetration depth between the two surfaces, including the ratio of α-Al2O3 after 500 h oxidation, were responsible for the oxidation anisotropy.

  10. Temperature dependence of nuclear surface properties

    International Nuclear Information System (INIS)

    Campi, X.; Stringari, S.

    1982-01-01

    Thermal properties of nuclear surface are investigated in a semi-infinite medium. Explicit analytical expression are given for the temperature dependence of surface thickness, surface energy and surface free energy. In this model the temperature effects depend critically on the nuclear incompressibility and on the shape of the effective mass at the surface. To illustrate the relevance of these effects we made an estimate of the temperature dependence of the fission barrier height. (orig.)

  11. Impact of satellite-based lake surface observations on the initial state of HIRLAM. Part II: Analysis of lake surface temperature and ice cover

    Directory of Open Access Journals (Sweden)

    Homa Kheyrollah Pour

    2014-09-01

    Full Text Available This paper presents results from a study on the impact of remote-sensing Lake Surface Water Temperature (LSWT observations in the analysis of lake surface state of a numerical weather prediction (NWP model. Data assimilation experiments were performed with the High Resolution Limited Area Model (HIRLAM, a three-dimensional operational NWP model. Selected thermal remote-sensing LSWT observations provided by the Moderate Resolution Imaging Spectroradiometer (MODIS and Advanced Along-Track Scanning Radiometer (AATSR sensors onboard the Terra/Aqua and ENVISAT satellites, respectively, were included into the assimilation. The domain of our experiments, which focussed on two winters (2010–2011 and 2011–2012, covered northern Europe. Validation of the resulting objective analyses against independent observations demonstrated that the description of the lake surface state can be improved by the introduction of space-borne LSWT observations, compared to the result of pure prognostic parameterisations or assimilation of the available limited number of in-situ lake temperature observations. Further development of the data assimilation methods and solving of several practical issues are necessary in order to fully benefit from the space-borne observations of lake surface state for the improvement of the operational weather forecast. This paper is the second part of a series of two papers aimed at improving the objective analysis of lake temperature and ice conditions in HIRLAM.

  12. Sea surface salinity and temperature-based predictive modeling of southwestern US winter precipitation: improvements, errors, and potential mechanisms

    Science.gov (United States)

    Liu, T.; Schmitt, R. W.; Li, L.

    2017-12-01

    Using 69 years of historical data from 1948-2017, we developed a method to globally search for sea surface salinity (SSS) and temperature (SST) predictors of regional terrestrial precipitation. We then applied this method to build an autumn (SON) SSS and SST-based 3-month lead predictive model of winter (DJF) precipitation in southwestern United States. We also find that SSS-only models perform better than SST-only models. We previously used an arbitrary correlation coefficient (r) threshold, |r| > 0.25, to define SSS and SST predictor polygons for best subset regression of southwestern US winter precipitation; from preliminary sensitivity tests, we find that |r| > 0.18 yields the best models. The observed below-average precipitation (0.69 mm/day) in winter 2015-2016 falls within the 95% confidence interval of the prediction model. However, the model underestimates the anomalous high precipitation (1.78 mm/day) in winter 2016-2017 by more than three-fold. Moisture transport mainly attributed to "pineapple express" atmospheric rivers (ARs) in winter 2016-2017 suggests that the model falls short on a sub-seasonal scale, in which case storms from ARs contribute a significant portion of seasonal terrestrial precipitation. Further, we identify a potential mechanism for long-range SSS and precipitation teleconnections: standing Rossby waves. The heat applied to the atmosphere from anomalous tropical rainfall can generate standing Rossby waves that propagate to higher latitudes. SSS anomalies may be indicative of anomalous tropical rainfall, and by extension, standing Rossby waves that provide the long-range teleconnections.

  13. Retrieval of land surface temperature (LST) from landsat TM6 and TIRS data by single channel radiative transfer algorithm using satellite and ground-based inputs

    Science.gov (United States)

    Chatterjee, R. S.; Singh, Narendra; Thapa, Shailaja; Sharma, Dravneeta; Kumar, Dheeraj

    2017-06-01

    The present study proposes land surface temperature (LST) retrieval from satellite-based thermal IR data by single channel radiative transfer algorithm using atmospheric correction parameters derived from satellite-based and in-situ data and land surface emissivity (LSE) derived by a hybrid LSE model. For example, atmospheric transmittance (τ) was derived from Terra MODIS spectral radiance in atmospheric window and absorption bands, whereas the atmospheric path radiance and sky radiance were estimated using satellite- and ground-based in-situ solar radiation, geographic location and observation conditions. The hybrid LSE model which is coupled with ground-based emissivity measurements is more versatile than the previous LSE models and yields improved emissivity values by knowledge-based approach. It uses NDVI-based and NDVI Threshold method (NDVITHM) based algorithms and field-measured emissivity values. The model is applicable for dense vegetation cover, mixed vegetation cover, bare earth including coal mining related land surface classes. The study was conducted in a coalfield of India badly affected by coal fire for decades. In a coal fire affected coalfield, LST would provide precise temperature difference between thermally anomalous coal fire pixels and background pixels to facilitate coal fire detection and monitoring. The derived LST products of the present study were compared with radiant temperature images across some of the prominent coal fire locations in the study area by graphical means and by some standard mathematical dispersion coefficients such as coefficient of variation, coefficient of quartile deviation, coefficient of quartile deviation for 3rd quartile vs. maximum temperature, coefficient of mean deviation (about median) indicating significant increase in the temperature difference among the pixels. The average temperature slope between adjacent pixels, which increases the potential of coal fire pixel detection from background pixels, is

  14. Surface sulfonamide modification of poly(N-isopropylacrylamide)-based block copolymer micelles to alter pH and temperature responsive properties for controlled intracellular uptake.

    Science.gov (United States)

    Cyphert, Erika L; von Recum, Horst A; Yamato, Masayuki; Nakayama, Masamichi

    2018-06-01

    Two different surface sulfonamide-functionalized poly(N-isopropylacrylamide)-based polymeric micelles were designed as pH-/temperature-responsive vehicles. Both sulfadimethoxine- and sulfamethazine-surface functionalized micelles were characterized to determine physicochemical properties, hydrodynamic diameters, zeta potentials, temperature-dependent size changes, and lower critical solution temperatures (LCST) in both pH 7.4 and 6.8 solutions (simulating both physiological and mild low pH conditions), and tested in the incorporation of a proof-of-concept hydrophobic antiproliferative drug, paclitaxel. Cellular uptake studies were conducted using bovine carotid endothelial cells and fluorescently labeled micelles to evaluate if there was enhanced cellular uptake of the micelles in a low pH environment. Both variations of micelles showed enhanced intracellular uptake under mildly acidic (pH 6.8) conditions at temperatures slightly above their LCST and minimal uptake at physiological (pH 7.4) conditions. Due to the less negative zeta potential of the sulfamethazine-surface micelles compared to sulfadimethoxine-surface micelles, and the proximity of their LCST to physiological temperature (37°C), the sulfamethazine variation was deemed more amenable for clinically relevant temperature and pH-stimulated applications. Nevertheless, we believe both polymeric micelle variations have the capacity to be implemented as an intracellular drug or gene delivery system in response to mildly acidic conditions. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1552-1560, 2018. © 2018 Wiley Periodicals, Inc.

  15. The Pacific sea surface temperature

    International Nuclear Information System (INIS)

    Douglass, David H.

    2011-01-01

    The Pacific sea surface temperature data contains two components: N L , a signal that exhibits the familiar El Niño/La Niña phenomenon and N H , a signal of one-year period. Analysis reveals: (1) The existence of an annual solar forcing F S ; (2) N H is phase locked directly to F S while N L is frequently phase locked to the 2nd or 3rd subharmonic of F S . At least ten distinct subharmonic time segments of N L since 1870 are found. The beginning or end dates of these segments have a near one-to-one correspondence with the abrupt climate changes previously reported. Limited predictability is possible. -- Highlights: ► El Niño/La Niña consists of 2 components phase-locked to annual solar cycle. ► The first component N L is the familiar El Niño/La Niña effect. ► The second N H component has a period of 1 cycle/year. ► N L can be phase-locked to 2nd or 3rd subharmonic of annual cycle. ► Ends of phase-locked segments correspond to abrupt previously reported climate changes.

  16. The Pacific sea surface temperature

    Energy Technology Data Exchange (ETDEWEB)

    Douglass, David H., E-mail: douglass@pas.rochester.edu [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627-0171 (United States)

    2011-12-05

    The Pacific sea surface temperature data contains two components: N{sub L}, a signal that exhibits the familiar El Niño/La Niña phenomenon and N{sub H}, a signal of one-year period. Analysis reveals: (1) The existence of an annual solar forcing F{sub S}; (2) N{sub H} is phase locked directly to F{sub S} while N{sub L} is frequently phase locked to the 2nd or 3rd subharmonic of F{sub S}. At least ten distinct subharmonic time segments of N{sub L} since 1870 are found. The beginning or end dates of these segments have a near one-to-one correspondence with the abrupt climate changes previously reported. Limited predictability is possible. -- Highlights: ► El Niño/La Niña consists of 2 components phase-locked to annual solar cycle. ► The first component N{sub L} is the familiar El Niño/La Niña effect. ► The second N{sub H} component has a period of 1 cycle/year. ► N{sub L} can be phase-locked to 2nd or 3rd subharmonic of annual cycle. ► Ends of phase-locked segments correspond to abrupt previously reported climate changes.

  17. Modelling global fresh surface water temperature

    NARCIS (Netherlands)

    Beek, L.P.H. van; Eikelboom, T.; Vliet, M.T.H. van; Bierkens, M.F.P.

    2011-01-01

    Temperature directly determines a range of water physical properties including vapour pressure, surface tension, density and viscosity, and the solubility of oxygen and other gases. Indirectly water temperature acts as a strong control on fresh water biogeochemistry, influencing sediment

  18. Hot surface temperatures of domestic appliances.

    Science.gov (United States)

    Bassett, Malcolm; Arild, Anne-Helene

    2002-09-01

    Domestic appliances are burning people. In the European Union, accidents requiring hospital treatment due to burns from hot objects account for between 0 and 1% of all such accidents. Young children are particularly at risk. These reported accidents requiring hospital treatment are also likely to be a small proportion of the total number of burns from hot objects. There is a lack of hard evidence about the level of accidents, typical consumer expectation and use, and on the state of the art of appliances. Results of technical laboratory tests carried out on products are used to demonstrate the state of the art and also show how consumer expectations could be changing. Results of a survey into accidents, based on a written questionnaire following telephone contact, provide information on non-hospital cases. Results of tests on products show that there are significant differences in the temperatures of touchable surfaces, even in products of the same type. Typically, these differences are due to variations in design and/or materials of construction. Some products are hot enough to burn skin. Accident research indicates that non-hospital medical practices are treating burn injuries, which are therefore not being included into the current accident statistics. For products with the same function, some types of design or materials of construction are safer, with lower surface temperatures. Many product standards have no or unnecessarily high limits on surface temperatures. Many standards do not address the realities of who is using their products, for what purpose or where they are located. Some standards use unreasonable general limitations and exclusions that allow products with higher surface temperatures than they should have. Many standards rely on the experience factor for avoiding injury that is no longer valid, with the increased availability of safer products of the same type. A major field of work ahead is to carry out more surveys and in-depth studies of non

  19. Improvements of a COMS Land Surface Temperature Retrieval Algorithm Based on the Temperature Lapse Rate and Water Vapor/Aerosol Effect

    Directory of Open Access Journals (Sweden)

    A-Ra Cho

    2015-02-01

    Full Text Available The National Meteorological Satellite Center in Korea retrieves land surface temperature (LST by applying the split-window LST algorithm (CSW_v1.0 to Communication, Ocean, and Meteorological Satellite (COMS data. Considerable errors were detected under conditions of high water vapor content or temperature lapse rates during validation with Moderate Resolution Imaging Spectroradiometer (MODIS LST because of the too simplified LST algorithm. In this study, six types of LST retrieval equations (CSW_v2.0 were developed to upgrade the CSW_v1.0. These methods were developed by classifying “dry,” “normal,” and “wet” cases for day and night and considering the relative sizes of brightness temperature difference (BTD values. Similar to CSW_v1.0, the LST retrieved by CSW_v2.0 had a correlation coefficient of 0.99 with the prescribed LST and a slightly larger bias of −0.03 K from 0.00K; the root mean square error (RMSE improved from 1.41 K to 1.39 K. In general, CSW_v2.0 improved the retrieval accuracy compared to CSW_v1.0, especially when the lapse rate was high (mid-day and dawn and the water vapor content was high. The spatial distributions of LST retrieved by CSW_v2.0 were found to be similar to the MODIS LST independently of the season, day/night, and geographic locations. The validation using one year’s MODIS LST data showed that CSW_v2.0 improved the retrieval accuracy of LST in terms of correlations (from 0.988 to 0.989, bias (from −1.009 K to 0.292 K, and RMSEs (from 2.613 K to 2.237 K.

  20. Near-surface temperature inversion during summer at Summit, Greenland, and its relation to MODIS-derived surface temperatures

    Science.gov (United States)

    Adolph, Alden C.; Albert, Mary R.; Hall, Dorothy K.

    2018-03-01

    As rapid warming of the Arctic occurs, it is imperative that climate indicators such as temperature be monitored over large areas to understand and predict the effects of climate changes. Temperatures are traditionally tracked using in situ 2 m air temperatures and can also be assessed using remote sensing techniques. Remote sensing is especially valuable over the Greenland Ice Sheet, where few ground-based air temperature measurements exist. Because of the presence of surface-based temperature inversions in ice-covered areas, differences between 2 m air temperature and the temperature of the actual snow surface (referred to as skin temperature) can be significant and are particularly relevant when considering validation and application of remote sensing temperature data. We present results from a field campaign extending from 8 June to 18 July 2015, near Summit Station in Greenland, to study surface temperature using the following measurements: skin temperature measured by an infrared (IR) sensor, 2 m air temperature measured by a National Oceanic and Atmospheric Administration (NOAA) meteorological station, and a Moderate Resolution Imaging Spectroradiometer (MODIS) surface temperature product. Our data indicate that 2 m air temperature is often significantly higher than snow skin temperature measured in situ, and this finding may account for apparent biases in previous studies of MODIS products that used 2 m air temperature for validation. This inversion is present during our study period when incoming solar radiation and wind speed are both low. As compared to our in situ IR skin temperature measurements, after additional cloud masking, the MOD/MYD11 Collection 6 surface temperature standard product has an RMSE of 1.0 °C and a mean bias of -0.4 °C, spanning a range of temperatures from -35 to -5 °C (RMSE = 1.6 °C and mean bias = -0.7 °C prior to cloud masking). For our study area and time series, MODIS surface temperature products agree with skin surface

  1. Suppressed Acrylamide Formation during Baking in Yeast-Leavened Bread Based on added Asparaginase, Baking Time and Temperature Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Mashaer Matouri

    2018-01-01

    Full Text Available  Background and Objective: Acrylamide as a toxic substance for human beings is produced by Maillard reaction at high temperatures. In this research, this reaction can be inhibited based on using aspariganse enzyme, controlling the cooking time and temperature during baking in yeast-leavened bread.Material and Methods: In this study, a response surface methodology 5-level-3-factor central composite design was applied to study the effects of asparaginase (300-900 U Kg-1 of flour, baking temperature (230-280°C and baking time (13-16 min on acrylamide formation in yeast-leavened wheat bread.Results and Conclusion: Added asparaginase showed a reducing effect on acrylamide formation (p≤0.0001. Baking temperature significantly increased the acrylamide content in bread (p≤0.0001. A strong correlation was found between the baking temperature and acrylamide formation. Baking time and its interaction with asparaginase had a low but significant reducing effect on acrylamide content in bread (p≤0.0001. Three parameters of the cooking temperature and time as well as enzyme concentration have been optimized using response surface methodology, their values obtained 245.71°C, 14.55 min and 752.15 U Kg-1, respectively. Enzymatic process could be suggested as a safe and convenient method for preventing acrylamide formation in bread making.Conflict of interest: The authors declare no conflict of interest. 

  2. Inferring Land Surface Model Parameters for the Assimilation of Satellite-Based L-Band Brightness Temperature Observations into a Soil Moisture Analysis System

    Science.gov (United States)

    Reichle, Rolf H.; De Lannoy, Gabrielle J. M.

    2012-01-01

    The Soil Moisture and Ocean Salinity (SMOS) satellite mission provides global measurements of L-band brightness temperatures at horizontal and vertical polarization and a variety of incidence angles that are sensitive to moisture and temperature conditions in the top few centimeters of the soil. These L-band observations can therefore be assimilated into a land surface model to obtain surface and root zone soil moisture estimates. As part of the observation operator, such an assimilation system requires a radiative transfer model (RTM) that converts geophysical fields (including soil moisture and soil temperature) into modeled L-band brightness temperatures. At the global scale, the RTM parameters and the climatological soil moisture conditions are still poorly known. Using look-up tables from the literature to estimate the RTM parameters usually results in modeled L-band brightness temperatures that are strongly biased against the SMOS observations, with biases varying regionally and seasonally. Such biases must be addressed within the land data assimilation system. In this presentation, the estimation of the RTM parameters is discussed for the NASA GEOS-5 land data assimilation system, which is based on the ensemble Kalman filter (EnKF) and the Catchment land surface model. In the GEOS-5 land data assimilation system, soil moisture and brightness temperature biases are addressed in three stages. First, the global soil properties and soil hydraulic parameters that are used in the Catchment model were revised to minimize the bias in the modeled soil moisture, as verified against available in situ soil moisture measurements. Second, key parameters of the "tau-omega" RTM were calibrated prior to data assimilation using an objective function that minimizes the climatological differences between the modeled L-band brightness temperatures and the corresponding SMOS observations. Calibrated parameters include soil roughness parameters, vegetation structure parameters

  3. Inverse analysis of inner surface temperature history from outer surface temperature measurement of a pipe

    International Nuclear Information System (INIS)

    Kubo, S; Ioka, S; Onchi, S; Matsumoto, Y

    2010-01-01

    When slug flow runs through a pipe, nonuniform and time-varying thermal stresses develop and there is a possibility that thermal fatigue occurs. Therefore it is necessary to know the temperature distributions and the stress distributions in the pipe for the integrity assessment of the pipe. It is, however, difficult to measure the inner surface temperature directly. Therefore establishment of the estimation method of the temperature history on inner surface of pipe is needed. As a basic study on the estimation method of the temperature history on the inner surface of a pipe with slug flow, this paper presents an estimation method of the temperature on the inner surface of a plate from the temperature on the outer surface. The relationship between the temperature history on the outer surface and the inner surface is obtained analytically. Using the results of the mathematical analysis, the inverse analysis method of the inner surface temperature history estimation from the outer surface temperature history is proposed. It is found that the inner surface temperature history can be estimated from the outer surface temperature history by applying the inverse analysis method, even when it is expressed by the multiple frequency components.

  4. evaluation of land surface temperature parameterization ...

    African Journals Online (AJOL)

    user

    Surface temperature (Ts) is vital to the study of land-atmosphere interactions and ... representation of Ts in Global Climate Models using available ..... Obviously, the influence of the ambient .... diurnal cycle over land under clear and cloudy.

  5. Sea Surface Temperature Average_SST_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sea surface temperature collected via satellite imagery from http://www.esrl.noaa.gov/psd/data/gridded/data.noaa.ersst.html and averaged for each region using ArcGIS...

  6. Analysed foundation sea surface temperature, global

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The through-cloud capabilities of microwave radiometers provide a valuable picture of global sea surface temperature (SST). To utilize this, scientists at Remote...

  7. Sea Surface Temperature (14 KM North America)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Product shows local sea surface temperatures (degrees C). It is a composite gridded-image derived from 8-km resolution SST Observations. It is generated every 48...

  8. OW NOAA GOES Sea-Surface Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset contains satellite-derived sea-surface temperature measurements collected by means of the Geostationary Orbiting Environmental Satellite. The data is...

  9. NOAA Daily Optimum Interpolation Sea Surface Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA 1/4° daily Optimum Interpolation Sea Surface Temperature (or daily OISST) is an analysis constructed by combining observations from different platforms...

  10. Evaluation of Flat Surface Temperature Probes

    Science.gov (United States)

    Beges, G.; Rudman, M.; Drnovsek, J.

    2011-01-01

    The objective of this paper is elaboration of elements related to metrological analysis in the field of surface temperature measurement. Surface temperature measurements are applicable in many fields. As examples, safety testing of electrical appliances and a pharmaceutical production line represent case studies for surface temperature measurements. In both cases correctness of the result of the surface temperature has an influence on final product safety and quality and thus conformity with specifications. This paper deals with the differences of flat surface temperature probes in measuring the surface temperature. For the purpose of safety testing of electrical appliances, surface temperature measurements are very important for safety of the user. General requirements are presented in European standards, which support requirements in European directives, e.g., European Low Voltage Directive 2006/95/EC and pharmaceutical requirements, which are introduced in official state legislation. This paper introduces a comparison of temperature measurements of an attached thermocouple on the measured surface and measurement with flat surface temperature probes. As a heat generator, a so called temperature artifact is used. It consists of an aluminum plate with an incorporated electrical heating element with very good temperature stability in the central part. The probes and thermocouple were applied with different forces to the surface in horizontal and vertical positions. The reference temperature was measured by a J-type fine-wire (0.2 mm) thermocouple. Two probes were homemade according to requirements in the European standard EN 60335-2-9/A12, one with a fine-wire (0.2 mm) thermocouple and one with 0.5mm of thermocouple wire diameter. Additional commercially available probes were compared. Differences between probes due to thermal conditions caused by application of the probe were found. Therefore, it can happen that measurements are performed with improper equipment or

  11. Low temperature self-cleaning properties of superhydrophobic surfaces

    Science.gov (United States)

    Wang, Fajun; Shen, Taohua; Li, Changquan; Li, Wen; Yan, Guilong

    2014-10-01

    Outdoor surfaces are usually dirty surfaces. Ice accretion on outdoor surfaces could lead to serious accidents. In the present work, the superhydrophobic surface based on 1H, 1H, 2H, 2H-Perfluorodecanethiol (PFDT) modified Ag/PDMS composite was prepared to investigate the anti-icing property and self-cleaning property at temperatures below freezing point. The superhydrophobic surface was deliberately polluted with activated carbon before testing. It was observed that water droplet picked up dusts on the cold superhydrophobic surface and took it away without freezing at a measuring temperature of -10 °C. While on a smooth PFDT surface and a rough surface base on Ag/PDMS composite without PFDT modification, water droplets accumulated and then froze quickly at the same temperature. However, at even lower temperature of -12 °C, the superhydrophobic surface could not prevent the surface water from icing. In addition, it was observed that the frost layer condensed from the moisture pay an important role in determining the low temperature self-cleaning properties of a superhydrophobic surface.

  12. Effect of holes on the room temperature tensile behaviors of thin wall specimens with (210) side surface of Ni-base single crystal superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Z.J.; Liu, T.; Pu, S. [Superalloys Division, Institute of Metal Research, Chinese Academy of Sciences, No. 72, Wenhua Road, Shenyang 110016 (China); Xu, H. [Materials Fatigue and Fracture Division, Institute of Metal Research, Chinese Academy of Sciences, No. 72, Wenhua Road, Shenyang 110016 (China); Wang, L., E-mail: wangli@imr.ac.cn [Superalloys Division, Institute of Metal Research, Chinese Academy of Sciences, No. 72, Wenhua Road, Shenyang 110016 (China); Lou, L.H. [Superalloys Division, Institute of Metal Research, Chinese Academy of Sciences, No. 72, Wenhua Road, Shenyang 110016 (China)

    2015-10-25

    Tensile properties of Ni-base single crystal superalloy plate specimens with and without a hole at room temperature were studied in the present paper. During the testing process, an ARAMIS system based on the digital image correlation technique and in-situ scanning electron microscopy were employed to in-situ observe the strain distribution and slip traces development on the sample surfaces. It was demonstrated that the yield stress was decreased with the appearance of a hole due to the stress concentration. The results were analyzed based on the stress and strain states of specimens and the slip traces development observed on specimen surfaces. - Graphical abstract: The strain distribution for samples without and with a hole, respectively. - Highlights: • Tensile tests of plate specimens without and with a hole were performed. • Surface strain fields were in-situ observed by ARAMIS system. • Slip traces development on sample surfaces was in-situ observed by SEM. • The hole deteriorated both the tensile strength and elongation of the samples. • Tensile strength of specimens without and with a hole was discussed respectively.

  13. International Surface Temperature Initiative (ISTI) Global Land Surface Temperature Databank - Stage 2 Monthly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The global land surface temperature databank contains monthly timescale mean, max, and min temperature for approximately 40,000 stations globally. It was developed...

  14. International Surface Temperature Initiative (ISTI) Global Land Surface Temperature Databank - Stage 3 Monthly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Land Surface Temperature Databank contains monthly timescale mean, maximum, and minimum temperature for approximately 40,000 stations globally. It was...

  15. International Surface Temperature Initiative (ISTI) Global Land Surface Temperature Databank - Stage 2 Daily

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The global land surface temperature databank contains monthly timescale mean, max, and min temperature for approximately 40,000 stations globally. It was developed...

  16. International Surface Temperature Initiative (ISTI) Global Land Surface Temperature Databank - Stage 1 Monthly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The global land surface temperature databank contains monthly timescale mean, max, and min temperature for approximately 40,000 stations globally. It was developed...

  17. International Surface Temperature Initiative (ISTI) Global Land Surface Temperature Databank - Stage 1 Daily

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The global land surface temperature databank contains monthly timescale mean, max, and min temperature for approximately 40,000 stations globally. It was developed...

  18. SEASONAL CHANGES IN TITAN'S SURFACE TEMPERATURES

    International Nuclear Information System (INIS)

    Jennings, D. E.; Cottini, V.; Nixon, C. A.; Flasar, F. M.; Kunde, V. G.; Samuelson, R. E.; Romani, P. N.; Hesman, B. E.; Carlson, R. C.; Gorius, N. J. P.; Coustenis, A.; Tokano, T.

    2011-01-01

    Seasonal changes in Titan's surface brightness temperatures have been observed by Cassini in the thermal infrared. The Composite Infrared Spectrometer measured surface radiances at 19 μm in two time periods: one in late northern winter (LNW; L s = 335 deg.) and another centered on northern spring equinox (NSE; L s = 0 deg.). In both periods we constructed pole-to-pole maps of zonally averaged brightness temperatures corrected for effects of the atmosphere. Between LNW and NSE a shift occurred in the temperature distribution, characterized by a warming of ∼0.5 K in the north and a cooling by about the same amount in the south. At equinox the polar surface temperatures were both near 91 K and the equator was at 93.4 K. We measured a seasonal lag of ΔL S ∼ 9 0 in the meridional surface temperature distribution, consistent with the post-equinox results of Voyager 1 as well as with predictions from general circulation modeling. A slightly elevated temperature is observed at 65 0 S in the relatively cloud-free zone between the mid-latitude and southern cloud regions.

  19. Long chain diol index (LDI) as an organic-based sea surface temperature proxy in the Korean East Sea (NW Pacific)

    Science.gov (United States)

    Gal, Jong-Ku; Kim, Jung-Hyun; Kang, Su-Jin; Lee, Dong-Hun; Shin, Kyung-Hoon

    2016-04-01

    Long chain diol index (LDI) was introduced as an organic-based sea surface temperature (SST) proxy. LDI is expressed as the C30 1,15-diol abundance relative to those of C28 1,13-, C30 1,13- and C30 1,15-diols. There were a few studies which accessed the potential of LDI based on the culture, core top sediments, suspended particulate organic matters, and down-core sediments. However it is still unknown about the source of the diols and robustness as the SST proxy in the various marine environments. In the current study, we examined the applicability of the LDI in the East Sea of Korea where productivity and thus sedimentation rates are high. We will compare the LDI data with those of alkenone-based UK'37 by analyzing two multicores covering the last 100 year.

  20. Metal ion induced room temperature phase transformation and stimulated infrared spectroscopy on TiO{sub 2}-based surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gole, James L. [Schools of Physics and Mechanical Engineering, Georgia Institute of Technology, 837 State Street, Atlanta, GA 30332-0430 (United States)], E-mail: jim.gole@physics.gatech.edu; Prokes, S.M. [Code 6876, NRL, Washington, DC 20375 (United States)], E-mail: prokes@estd.nrl.navy.mil; White, Mark G. [Dave C. Swalm School of Chemical Engineering, James Worth Bagley College of Engineering, Box 959, MS 39762 (United States)], E-mail: white@che.msstate.edu

    2008-11-30

    Raman and infrared spectroscopy are used to demonstrate (1) the high spin metal ion induced room temperature transformation of anatase to rutile TiO{sub 2} and (2) the phenomena of stimulated IR spectroscopy induced by simultaneous nitrogen doping and high spin metal ion seeding of a TiO{sub 2} nanocolloid lattice.

  1. Metal ion induced room temperature phase transformation and stimulated infrared spectroscopy on TiO2-based surfaces

    International Nuclear Information System (INIS)

    Gole, James L.; Prokes, S.M.; White, Mark G.

    2008-01-01

    Raman and infrared spectroscopy are used to demonstrate (1) the high spin metal ion induced room temperature transformation of anatase to rutile TiO 2 and (2) the phenomena of stimulated IR spectroscopy induced by simultaneous nitrogen doping and high spin metal ion seeding of a TiO 2 nanocolloid lattice

  2. Infrared thermography - a non-invasive tool to evaluate thermal status of neonatal pigs based on surface temperature

    DEFF Research Database (Denmark)

    Sund Kammersgaard, Trine; Malmkvist, Jens; Pedersen, Lene Juul

    2013-01-01

    and IRmax was improved (Ppiglets having RT... to be used without the need for manual restraint of the pigs. On the basis of the results of this study, we propose that IRmax temperature from full-body thermograms has implication as a valid tool to assess the thermal status in neonatal piglets but not as an identical substitute for RT....

  3. Assessing regional crop water demand using a satellite-based combination equation with a land surface temperature componen

    DEFF Research Database (Denmark)

    Moyano, Carmen; Garcia, Monica; Tornos, Lucia

    2015-01-01

    -sequence spanning for more than a decade (2002-2013). The thermal-PT-JPL model was forced with vegetation, albedo, reflectance and temperature products from the Moderate-resolution Imaging Spectroradiometer (MODIS) from both Aqua and Terra satellites. The study region, B-XII Irrigation District of the Lower...

  4. Density, viscosity, and surface tension of synthesis grade imidazolium,pyridinium, and pyrrolidinium based room temperature ionic liquids

    NARCIS (Netherlands)

    Galan Sanchez, L.M.; Espel, J.R.; Onink, S.A.F.; Meindersma, G.W.; Haan, de A.B.

    2009-01-01

    Density, viscosity, and surface tension data sets of 13 ionic liquids formed by imidazolium, pyridinium, or pyrrolidinium cations paired with dicyanamide (DCA), tetrafluoroborate (BF4¯), thiocyanate (SCN¯),methylsulfate (MeSO4¯), and trifluoroacetate (TFA) anions are reported. The properties were

  5. Evaluating Coral Health in La Parguera, Puerto Rico, and Southeastern Florida: Comparison of Satellite-Based Sea Surface Temperature to In Situ Observations

    Science.gov (United States)

    Gomez, A. M.; McDonald, K. C.; Shein, K. A.; Devries, S. L.; Armstrong, R.; Carlo, M.

    2017-12-01

    The third global coral bleaching event, which began in mid-2014, is a major environmental stressor that has been causing significant documented damage to coral reefs in all tropical ocean basins. This worldwide phenomenon is the longest and largest coral bleaching event on record and now finally appears to be ending. During this event, some coral colonies proved to be more resilient to increased ocean temperatures while others bleached severely. This research investigates the spatial and temporal variability of bleaching stress on coral reefs in La Parguera, Puerto Rico, and Southeastern Florida to help further understand the role of temperature and light in coral bleaching. We examine the microclimate within two coral reef systems, using in situ collections of temperature and light data from data loggers deployed throughout Cayo Enrique and Cayo Mario in La Parguera, and Lauderdale-By-The-Sea in FLorida. The in situ measurements are compared to NOAA Coral Reef Watch's 5-km sea surface temperature data as well as to the associated Light Stress Damage Product. Research outcomes include statistical analyses of in situ measurements with satellite datasets supporting enhanced interpretation of satellite-based SST and light products, and ecological niche modeling to assess where corals could potentially survive under future climate conditions. Additional understanding of the microclimate encompassing coral reefs and improved satellite SST and light data will ultimately help coral reef ecosystem managers and policy makers in prioritizing resources toward the monitoring and protection of coral reef ecosystems.

  6. Global Monitoring RSEM System for Crop Production by Incorporating Satellite-based Photosynthesis Rates and Anomaly Data of Sea Surface Temperature

    Science.gov (United States)

    Kaneko, D.; Sakuma, H.

    2014-12-01

    The first author has been developing RSEM crop-monitoring system using satellite-based assessment of photosynthesis, incorporating meteorological conditions. Crop production comprises of several stages and plural mechanisms based on leaf photosynthesis, surface energy balance, and the maturing of grains after fixation of CO2, along with water exchange through soil vegetation-atmosphere transfer. Grain production in prime countries appears to be randomly perturbed regionally and globally. Weather for crop plants reflects turbulent phenomena of convective and advection flows in atmosphere and surface boundary layer. It has been difficult for scientists to simulate and forecast weather correctly for sufficiently long terms to crop harvesting. However, severely poor harvests related to continental events must originate from a consistent mechanism of abnormal energetic flow in the atmosphere through both land and oceans. It should be remembered that oceans have more than 100 times of energy storage compared to atmosphere and ocean currents represent gigantic energy flows, strongly affecting climate. Anomalies of Sea Surface Temperature (SST), globally known as El Niño, Indian Ocean dipole, and Atlantic Niño etc., affect the seasonal climate on a continental scale. The authors aim to combine monitoring and seasonal forecasting, considering such mechanisms through land-ocean biosphere transfer. The present system produces assessments for all continents, specifically monitoring agricultural fields of main crops. Historical regions of poor and good harvests are compared with distributions of SST anomalies, which are provided by NASA GSFC. Those comparisons fairly suggest that the Worst harvest in 1993 and the Best in 1994 relate to the offshore distribution of low temperature anomalies and high gaps in ocean surface temperatures. However, high-temperature anomalies supported good harvests because of sufficient solar radiation for photosynthesis, and poor harvests because

  7. Surface temperature measurement with radioactive kryptonates

    International Nuclear Information System (INIS)

    Pruzinec, J.; Piatrik, M.

    1976-01-01

    The preparation and use of radioactive kryptonates is described for measuring surface temperatures within the region of 45 to 70 degC. Two samples each were prepared of kryptonated beechwood and hydroquinone on a paper carrier. One sample served as the standard which during the experiment was placed in a thermostat at a constant temperature of 45 degC. The second sample was placed in another thermostat where the temperature changed from 45 to 70 degC. Both samples were in the thermostat for 30 mins. The temperature was raised in steps of 2.5 degC and the time of measurement was constant in both samples. The dependences are given of the drop in activity on temperature for both types of samples. The difference was determined of the drop in activity between the standard and the second sample and the relation for measuring the temperature of the sample was determined therefrom. (J.B.)

  8. Surface temperature retrieval in a temperate grassland with multiresolution sensors

    Science.gov (United States)

    Goetz, S. J.; Halthore, R. N.; Hall, F. G.; Markham, B. L.

    1995-12-01

    Radiometric surface temperatures retrieved at various spatial resolutions from aircraft and satellite measurements at the FIFE site in eastern Kansas were compared with near-surface temperature measurements to determine the accuracy of the retrieval techniques and consistency between the various sensors. Atmospheric characterizations based on local radiosonde profiles of temperature, pressure, and water vapor were used with the LOWTRAN-7 and MODTRAN atmospheric radiance models to correct measured thermal radiances of water and grassland targets for atmospheric attenuation. Comparison of retrieved surface temperatures from a helicopter-mounted modular multispectral radiometer (MMR) (˜5-m "pixel"), C-130 mounted thematic mapper simulator (TMS) (NS001, ˜20-m pixel), and the Landsat 5 thematic mapper (TM) (120-m pixel) was done. Differences between atmospherically corrected radiative temperatures and near-surface measurements ranged from less than 1°C to more than 8°C. Corrected temperatures from helicopter-MMR and NS001-TMS were in general agreement with near-surface infrared radiative thermometer (IRT) measurements collected from automated meteorological stations, with mean differences of 3.2°C and 1.7°C for grassland targets. Much better agreement (within 1°C) was found between the retrieved aircraft surface temperatures and near-surface measurements acquired with a hand-held mast equipped with a MMR and IRT. The NS001-TMS was also in good agreement with near-surface temperatures acquired over water targets. In contrast, the Landsat 5 TM systematically overestimated surface temperature in all cases. This result has been noted previously but not consistently. On the basis of the results reported here, surface measurements were used to provide a calibration of the TM thermal channel. Further evaluation of the in-flight radiometric calibration of the TM thermal channel is recommended.

  9. Low temperature surface chemistry and nanostructures

    Science.gov (United States)

    Sergeev, G. B.; Shabatina, T. I.

    2002-03-01

    The new scientific field of low temperature surface chemistry, which combines the low temperature chemistry (cryochemistry) and surface chemistry approaches, is reviewed in this paper. One of the most exciting achievements in this field of science is the development of methods to create highly ordered hybrid nanosized structures on different organic and inorganic surfaces and to encapsulate nanosized metal particles in organic and polymer matrices. We consider physical and chemical behaviour for the systems obtained by co-condensation of the components vapours on the surfaces cooled down to 4-10 and 70-100 K. In particular the size effect of both types, the number of atoms in the reactive species structure and the thickness of growing co-condensate film, on the chemical activity of the system is analysed in detail. The effect of the internal mechanical stresses on the growing interfacial co-condensate film formation and on the generation of fast (explosive) spontaneous reactions at low temperatures is discussed. The examples of unusual chemical interactions of metal atoms, clusters and nanosized particles, obtained in co-condensate films on the cooled surfaces under different conditions, are presented. The examples of highly ordered surface and volume hybrid nanostructures formation are analysed.

  10. Sensitivity of Satellite-Based Skin Temperature to Different Surface Emissivity and NWP Reanalysis Sources Demonstrated Using a Single-Channel, Viewing-Angle-Corrected Retrieval Algorithm

    Science.gov (United States)

    Scarino, B. R.; Minnis, P.; Yost, C. R.; Chee, T.; Palikonda, R.

    2015-12-01

    Single-channel algorithms for satellite thermal-infrared- (TIR-) derived land and sea surface skin temperature (LST and SST) are advantageous in that they can be easily applied to a variety of satellite sensors. They can also accommodate decade-spanning instrument series, particularly for periods when split-window capabilities are not available. However, the benefit of one unified retrieval methodology for all sensors comes at the cost of critical sensitivity to surface emissivity (ɛs) and atmospheric transmittance estimation. It has been demonstrated that as little as 0.01 variance in ɛs can amount to more than a 0.5-K adjustment in retrieved LST values. Atmospheric transmittance requires calculations that employ vertical profiles of temperature and humidity from numerical weather prediction (NWP) models. Selection of a given NWP model can significantly affect LST and SST agreement relative to their respective validation sources. Thus, it is necessary to understand the accuracies of the retrievals for various NWP models to ensure the best LST/SST retrievals. The sensitivities of the single-channel retrievals to surface emittance and NWP profiles are investigated using NASA Langley historic land and ocean clear-sky skin temperature (Ts) values derived from high-resolution 11-μm TIR brightness temperature measured from geostationary satellites (GEOSat) and Advanced Very High Resolution Radiometers (AVHRR). It is shown that mean GEOSat-derived, anisotropy-corrected LST can vary by up to ±0.8 K depending on whether CERES or MODIS ɛs sources are used. Furthermore, the use of either NOAA Global Forecast System (GFS) or NASA Goddard Modern-Era Retrospective Analysis for Research and Applications (MERRA) for the radiative transfer model initial atmospheric state can account for more than 0.5-K variation in mean Ts. The results are compared to measurements from the Surface Radiation Budget Network (SURFRAD), an Atmospheric Radiation Measurement (ARM) Program ground

  11. Inkjet printed paper based frequency selective surfaces and skin mounted RFID tags : the interrelation between silver nanoparticle ink, paper substrate and low temperature sintering technique

    NARCIS (Netherlands)

    Sanchez-Romaquera, V.; Wïnscher, S.; Turki, B.M.; Abbel, R.J.; Barbosa, S.; Tate, D.J.; Oyeka, D.; Batchelor, J.C.; Parker, E.A.; Schubert, U.S.; Yeates, S.G.

    2015-01-01

    Inkjet printing of functional frequency selective surfaces (FSS) and radio frequency identification (RFID) tags on commercial paper substrates using silver nanoparticle inks sintered using low temperature thermal, plasma and photonic techniques is reported. Printed and sintered FSS devices

  12. Near-surface temperature inversion during summer at Summit, Greenland, and its relation to MODIS-derived surface temperatures

    Directory of Open Access Journals (Sweden)

    A. C. Adolph

    2018-03-01

    Full Text Available As rapid warming of the Arctic occurs, it is imperative that climate indicators such as temperature be monitored over large areas to understand and predict the effects of climate changes. Temperatures are traditionally tracked using in situ 2 m air temperatures and can also be assessed using remote sensing techniques. Remote sensing is especially valuable over the Greenland Ice Sheet, where few ground-based air temperature measurements exist. Because of the presence of surface-based temperature inversions in ice-covered areas, differences between 2 m air temperature and the temperature of the actual snow surface (referred to as skin temperature can be significant and are particularly relevant when considering validation and application of remote sensing temperature data. We present results from a field campaign extending from 8 June to 18 July 2015, near Summit Station in Greenland, to study surface temperature using the following measurements: skin temperature measured by an infrared (IR sensor, 2 m air temperature measured by a National Oceanic and Atmospheric Administration (NOAA meteorological station, and a Moderate Resolution Imaging Spectroradiometer (MODIS surface temperature product. Our data indicate that 2 m air temperature is often significantly higher than snow skin temperature measured in situ, and this finding may account for apparent biases in previous studies of MODIS products that used 2 m air temperature for validation. This inversion is present during our study period when incoming solar radiation and wind speed are both low. As compared to our in situ IR skin temperature measurements, after additional cloud masking, the MOD/MYD11 Collection 6 surface temperature standard product has an RMSE of 1.0 °C and a mean bias of −0.4 °C, spanning a range of temperatures from −35 to −5 °C (RMSE  =  1.6 °C and mean bias  =  −0.7 °C prior to cloud masking. For our study area and time series

  13. Low Temperature Surface Carburization of Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Sunniva R; Heuer, Arthur H; Sikka, Vinod K

    2007-12-07

    Thermodynamic modeling to explain the high degree of carbon solubility possible in austenitic grades under the LTCSS process and experimental validation of model results • Corrosion testing to determine the corrosion resistance improvement possible from the LTCSS process • Erosion testing to determine the erosion resistance improvement possible from the LTCSS process • Wear testing to quantify the wear resistance improvement possible from the LTCSS process • Fatigue testing for quantifying the extent of improvement from the LTCSS process • Component treating and testing under simulated and in-line commercial operations XRD verified expanded austenite lattice, with no evidence of carbide precipitation. Carbon concentration profiles via Auger and electron dispersion spectroscopy (EDS) showed carbon levels in excess of 12 at. % in treated, type 316 SS. Scanning electron microscopy (SEM) of pulled-to-failure treated tensile specimens showed slip bands and no de-cohesion of the treated layer, verifying that the layer remains ductile. Compressive stresses in excess of 2 GPa (300 ksi) have been calculated at the surface of the case. Phase diagram (CALPHAD) (ThermoCalc) and Wagner dilute solution thermodynamic models were developed that calculate the solubility of carbon in austenite as a function of alloying content for the process time and temperature. Several commercial alloys have been modeled, and the model has been used to design experimental alloys with enhanced affinity for carbon solubility at treatment temperatures. Four experimental alloys were melted, rolled, and manufactured into test specimens, and the LTCSS treatment indicated successfully enhanced results and validated the predictions based on thermodynamic modeling. Electrochemical polarization curves show a 600 to 800 mV increase in pitting potential in treated (900-1000 mV) versus non-treated (200-300 mV) type 316 in chloride solutions. Treated 316L showed crevice-corrosion behavior similar to that of Ti-6

  14. Trend patterns in global sea surface temperature

    DEFF Research Database (Denmark)

    Barbosa, S.M.; Andersen, Ole Baltazar

    2009-01-01

    Isolating long-term trend in sea surface temperature (SST) from El Nino southern oscillation (ENSO) variability is fundamental for climate studies. In the present study, trend-empirical orthogonal function (EOF) analysis, a robust space-time method for extracting trend patterns, is applied to iso...

  15. A satellite-based climatology (1989-2012) of lake surface water temperature from AVHRR 1-km for Central European water bodies

    Science.gov (United States)

    Riffler, Michael; Wunderle, Stefan

    2013-04-01

    The temperature of lakes is an important parameter for lake ecosystems influencing the speed of physio-chemical reactions, the concentration of dissolved gazes (e.g. oxygen), and vertical mixing. Even small temperature changes might have irreversible effects on the lacustrine system due to the high specific heat capacity of water. These effects could alter the quality of lake water depending on parameters like lake size and volume. Numerous studies mention lake water temperature as an indicator of climate change and in the Global Climate Observing System (GCOS) requirements it is listed as an essential climate variable. In contrast to in situ observations, satellite imagery offers the possibility to derive spatial patterns of lake surface water temperature (LSWT) and their variability. Moreover, although for some European lakes long in situ time series are available, the temperatures of many lakes are not measured or only on a non-regular basis making these observations insufficient for climate monitoring. However, only few satellite sensors offer the possibility to analyze time series which cover more than 20 years. The Advanced Very High Resolution Radiometer (AVHRR) is among these and has been flown on the National Oceanic and Atmospheric Administration (NOAA) Polar Operational Environmental Satellites (POES) and on the Meteorological Operational Satellites (MetOp) from the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) as a heritage instrument for almost 35 years. It will be carried on for at least ten more years finally offering a unique opportunity for satellite-based climate studies. Herein we present the results from a study initiated by the Swiss GCOS office to generate a satellite-based LSWT climatology for the pre-alpine water bodies in Switzerland. It relies on the extensive AVHRR 1-km data record (1985-2012) of the Remote Sensing Research Group at the University of Bern (RSGB) and has been derived from the AVHRR/2

  16. Temperature effect on surface oxidation of titanium

    International Nuclear Information System (INIS)

    Vaquilla, I.; Barco, J.L. del; Ferron, J.

    1990-01-01

    The effect of temperature on the first stages of the superficial oxidation of polycrystalline titanium was studied using both Auger electron spectroscopy (AES) and emission shreshold (AEAPS). The number of compounds present on the surface was determined by application of the factor analysis technique. Reaction evolution was followed through the relative variation of Auger LMM and LMV transitions which are characteristic of titanium. Also the evolution of the chemical shift was determined by AEAPS. The amount of oxygen on the surface was quantified using transition KLL of oxygen. It was found that superficial oxidation depends on temperature. As much as three different compounds were determined according to substrate temperature and our exposure ranges. (Author). 7 refs., 5 figs

  17. Estimation of surface air temperature over central and eastern Eurasia from MODIS land surface temperature

    International Nuclear Information System (INIS)

    Shen Suhung; Leptoukh, Gregory G

    2011-01-01

    Surface air temperature (T a ) is a critical variable in the energy and water cycle of the Earth–atmosphere system and is a key input element for hydrology and land surface models. This is a preliminary study to evaluate estimation of T a from satellite remotely sensed land surface temperature (T s ) by using MODIS-Terra data over two Eurasia regions: northern China and fUSSR. High correlations are observed in both regions between station-measured T a and MODIS T s . The relationships between the maximum T a and daytime T s depend significantly on land cover types, but the minimum T a and nighttime T s have little dependence on the land cover types. The largest difference between maximum T a and daytime T s appears over the barren and sparsely vegetated area during the summer time. Using a linear regression method, the daily maximum T a were estimated from 1 km resolution MODIS T s under clear-sky conditions with coefficients calculated based on land cover types, while the minimum T a were estimated without considering land cover types. The uncertainty, mean absolute error (MAE), of the estimated maximum T a varies from 2.4 °C over closed shrublands to 3.2 °C over grasslands, and the MAE of the estimated minimum T a is about 3.0 °C.

  18. Behavior of a thermoelectric power generation device based on solar irradiation and the earth’s surface-air temperature difference

    International Nuclear Information System (INIS)

    Zhang, Zhe; Li, Wenbin; Kan, Jiangming

    2015-01-01

    Highlights: • A technical solution to the power supply of wireless sensor networks is presented. • The low voltage produced by TEG is boosted from less than 1 V to more than 4 V. • An output current and voltage of TEG device is acquired as 21.47 mA and 221 mV. • The device successfully provides output power 4.7 mW in no electricity conditions. • The thermo-economic value of TEG device is demonstrated. - Abstract: Motivated by the limited power supply of wireless sensors used to monitor the natural environment, for example, in forests, this study presents a technical solution by recycling solar irradiation heat using thermoelectric generators. Based on solar irradiation and the earth’s surface-air temperature difference, a new type of thermoelectric power generation device has been devised, the distinguishing features of which include the application of an all-glass heat-tube-type vacuum solar heat collection pipe to absorb and transfer solar energy without a water medium and the use of a thin heat dissipation tube to cool the earth surface air temperature. The effects of key parameters such as solar illumination, air temperature, load resistance, the proportional coefficient, output power and power generation efficiency for thermoelectric energy conversion are analyzed. The results of realistic outdoor experiments show that under a state of regular illumination at 3.75 × 10 4 lx, using one TEG module, the thermoelectric device is able to boost the voltage obtained from the natural solar irradiation from 221 mV to 4.41 V, with an output power of 4.7 mW. This means that the electrical energy generated can provide the power supply for low power consumption components, such as low power wireless sensors, ZigBee modules and other low power loads

  19. Pattern Analysis of El Nino and La Nina Phenomenon Based on Sea Surface Temperature (SST) and Rainfall Intensity using Oceanic Nino Index (ONI) in West Java Area

    Science.gov (United States)

    Prasetyo, Yudo; Nabilah, Farras

    2017-12-01

    Climate change occurs in 1998-2016 brings significant alteration in the earth surface. It is affects an extremely anomaly temperature such as El Nino and La Nina or mostly known as ENSO (El Nino Southern Oscillation). West Java is one of the regions in Indonesia that encounters the impact of this phenomenon. Climate change due to ENSO also affects food production and other commodities. In this research, processing data method is conducted using programming language to process SST data and rainfall data from 1998 to 2016. The data are sea surface temperature from NOAA satellite, SST Reynolds (Sea Surface Temperature) and daily rainfall temperature from TRMM satellite. Data examination is done using analysis of rainfall spatial pattern and sea surface temperature (SST) where is affected by El Nino and La Nina phenomenon. This research results distribution map of SST and rainfall for each season to find out the impacts of El Nino and La Nina around West Java. El Nino and La Nina in Java Sea are occurring every August to February. During El Nino, sea surface temperature is between 27°C - 28°C with average temperature on 27.71°C. Rainfall intensity is 1.0 mm/day - 2.0 mm/day and the average are 1.63 mm/day. During La Nina, sea surface temperature is between 29°C - 30°C with average temperature on 29.06°C. Rainfall intensity is 9.0 mm/day - 10 mm/day, and the average is 9.74 mm/day. The correlation between rainfall and SST is 0,413 which is expresses a fairly strong correlation between parameters. The conclusion is, during La Nina SST and rainfall increase. While during El Nino SST and rainfall decrease. Hopefully this research could be a guideline to plan disaster mitigation in West Java region that is related extreme climate change.

  20. ALMA observation of Ceres' Surface Temperature.

    Science.gov (United States)

    Titus, T. N.; Li, J. Y.; Sykes, M. V.; Ip, W. H.; Lai, I.; Moullet, A.

    2016-12-01

    Ceres, the largest object in the main asteroid belt, has been mapped by the Dawn spacecraft. The mapping includes measuring surface temperatures using the Visible and Infrared (VIR) spectrometer at high spatial resolution. However, the VIR instrument has a long wavelength cutoff at 5 μm, which prevents the accurate measurement of surface temperatures below 180 K. This restricts temperature determinations to low and mid-latitudes at mid-day. Observations from the Atacama Large Millimeter/submillimeter Array (ALMA) [1], while having lower spatial resolution, are sensitive to the full range of surface temperatures that are expected at Ceres. Forty reconstructed images at 75 km/beam resolution were acquired of Ceres that were consistent with a low thermal inertia surface. The diurnal temperature profiles were compared to the KRC thermal model [2, 3], which has been extensively used for Mars [e.g. 4, 5]. Variations in temperature as a function of local time are observed and are compared to predictions from the KRC model. The model temperatures are converted to radiance (Jy/Steradian) and are corrected for near-surface thermal gradients and limb effects for comparison to observations. Initial analysis is consistent with the presence of near-surface water ice in the north polar region. The edge of the ice table is between 50° and 70° North Latitude, consistent with the enhanced detection of hydrogen by the Dawn GRaND instrument [6]. Further analysis will be presented. This work is supported by the NASA Solar System Observations Program. References: [1] Wootten A. et al. (2015) IAU General Assembly, Meeting #29, #2237199 [2] Kieffer, H. H., et al. (1977) JGR, 82, 4249-4291. [3] Kieffer, Hugh H., (2013) Journal of Geophysical Research: Planets, 118(3), 451-470. [4] Titus, T. N., H. H. Kieffer, and P. N. Christensen (2003) Science, 299, 1048-1051. [5] Fergason, R. L. et al. (2012) Space Sci. Rev, 170, 739-773[6] Prettyman, T. et al. (2016) LPSC 47, #2228.

  1. Analysis of teleconnections between AVHRR-based sea surface temperature and vegetation productivity in the semi-arid Sahel

    DEFF Research Database (Denmark)

    Huber Gharib, Silvia; Fensholt, Rasmus

    2011-01-01

    Vegetation Index (NDVI) in the Sahel, however with different magnitudes in terms of strength for the western, central and eastern Sahel. Also the correlations based on NDVI and global SST anomalies revealed the same East–West gradient, with a stronger association for the western than the eastern Sahel......, we achieved high correlations for SSTs of oceanic basins which are geographically associated to the climate indices yet by far not always these patterns were coherent. The detected SST–NDVI patterns could provide the basis to develop new means for improved forecasts in particular of the western...

  2. A Surface Temperature Initiated Closure (STIC) for surface energy balance fluxes

    DEFF Research Database (Denmark)

    Mallick, Kaniska; Jarvis, Andrew J.; Boegh, Eva

    2014-01-01

    The use of Penman–Monteith (PM) equation in thermal remote sensing based surface energy balance modeling is not prevalent due to the unavailability of any direct method to integrate thermal data into the PM equation and due to the lack of physical models expressing the surface (or stomatal......) and boundary layer conductances (gS and gB) as a function of surface temperature. Here we demonstrate a new method that physically integrates the radiometric surface temperature (TS) into the PM equation for estimating the terrestrial surface energy balance fluxes (sensible heat, H and latent heat, λ......E). The method combines satellite TS data with standard energy balance closure models in order to derive a hybrid closure that does not require the specification of surface to atmosphere conductance terms. We call this the Surface Temperature Initiated Closure (STIC), which is formed by the simultaneous solution...

  3. A model of the ground surface temperature for micrometeorological analysis

    Science.gov (United States)

    Leaf, Julian S.; Erell, Evyatar

    2017-07-01

    Micrometeorological models at various scales require ground surface temperature, which may not always be measured in sufficient spatial or temporal detail. There is thus a need for a model that can calculate the surface temperature using only widely available weather data, thermal properties of the ground, and surface properties. The vegetated/permeable surface energy balance (VP-SEB) model introduced here requires no a priori knowledge of soil temperature or moisture at any depth. It combines a two-layer characterization of the soil column following the heat conservation law with a sinusoidal function to estimate deep soil temperature, and a simplified procedure for calculating moisture content. A physically based solution is used for each of the energy balance components allowing VP-SEB to be highly portable. VP-SEB was tested using field data measuring bare loess desert soil in dry weather and following rain events. Modeled hourly surface temperature correlated well with the measured data (r 2 = 0.95 for a whole year), with a root-mean-square error of 2.77 K. The model was used to generate input for a pedestrian thermal comfort study using the Index of Thermal Stress (ITS). The simulation shows that the thermal stress on a pedestrian standing in the sun on a fully paved surface, which may be over 500 W on a warm summer day, may be as much as 100 W lower on a grass surface exposed to the same meteorological conditions.

  4. TWO METHODS FOR REMOTE ESTIMATION OF COMPLETE URBAN SURFACE TEMPERATURE

    Directory of Open Access Journals (Sweden)

    L. Jiang

    2017-09-01

    Full Text Available Complete urban surface temperature (TC is a key parameter for evaluating the energy exchange between the urban surface and atmosphere. At the present stage, the estimation of TC still needs detailed 3D structure information of the urban surface, however, it is often difficult to obtain the geometric structure and composition of the corresponding temperature of urban surface, so that there is still lack of concise and efficient method for estimating the TC by remote sensing. Based on the four typical urban surface scale models, combined with the Envi-met model, thermal radiant directionality forward modeling and kernel model, we analyzed a complete day and night cycle hourly component temperature and radiation temperature in each direction of two seasons of summer and winter, and calculated hemispherical integral temperature and TC. The conclusion is obtained by examining the relationship of directional radiation temperature, hemispherical integral temperature and TC: (1 There is an optimal angle of radiation temperature approaching the TC in a single observation direction when viewing zenith angle is 45–60°, the viewing azimuth near the vertical surface of the sun main plane, the average absolute difference is about 1.1 K in the daytime. (2 There are several (3–5 times directional temperatures of different view angle, under the situation of using the thermal radiation directionality kernel model can more accurately calculate the hemispherical integral temperature close to TC, the mean absolute error is about 1.0 K in the daytime. This study proposed simple and effective strategies for estimating TC by remote sensing, which are expected to improve the quantitative level of remote sensing of urban thermal environment.

  5. The Effect of Growth Temperature and V/III Flux Ratio of MOCVD Antimony Based Semiconductors on Growth Rate and Surface Morphology

    Directory of Open Access Journals (Sweden)

    Ramelan Ari Handono

    2017-01-01

    Full Text Available Epitaxial Alx Ga1-x Sb layers on GaSb and GaAs substrates have been grown by atmospheric pressure metalorganic chemical vapor deposition using TMAl, TMGa and TMSb. Nomarski microscope and a profiler were employed to examine the surface morphology and growth rate of the samples. We report the effect of growth temperature and V/III flux ratio on growth rate and surface morphology. Growth temperatures in the range of 520°C and 680°C and V/III ratios from 1 to 5 have been investigated. A growth rate activation energy of 0.73 eV was found. At low growth temperatures between 520 and 540°C, the surface morphology is poor due to antimonide precipitates associated with incomplete decomposition of the TMSb. For layers grown on GaAs at 580°C and 600°C with a V/III ratio of 3 a high quality surface morphology is typical, with a mirror-like surface and good composition control. It was found that a suitable growth temperature and V/III flux ratio was beneficial for producing good AlGaSb layers. Undoped AlGaSb grown at 580°C with a V/III flux ratio of 3 at the rate of 3.5 μm/hour shows p-type conductivity with smooth surface morphology

  6. Ensemble forecasts of road surface temperatures

    Czech Academy of Sciences Publication Activity Database

    Sokol, Zbyněk; Bližňák, Vojtěch; Sedlák, Pavel; Zacharov, Petr, jr.; Pešice, Petr; Škuthan, M.

    2017-01-01

    Roč. 187, 1 May (2017), s. 33-41 ISSN 0169-8095 R&D Projects: GA ČR GA13-34856S; GA TA ČR(CZ) TA01031509 Institutional support: RVO:68378289 Keywords : ensemble prediction * road surface temperature * road weather forecast Subject RIV: DG - Athmosphere Sciences, Meteorology OBOR OECD: Meteorology and atmospheric sciences Impact factor: 3.778, year: 2016 http://www.sciencedirect.com/science/article/pii/S0169809516307311

  7. LOFT fuel rod surface temperature measurement testing

    International Nuclear Information System (INIS)

    Eaton, A.M.; Tolman, E.L.; Solbrig, C.W.

    1978-01-01

    Testing of the LOFT fuel rod cladding surface thermocouples has been performed to evaluate how accurately the LOFT thermocouples measure the cladding surface temperature during a loss-of-coolant accident (LOCA) sequence and what effect, if any, the thermocouple would have on core performance. Extensive testing has been done to characterize the thermocouple design. Thermal cycling and corrosion testing of the thermocouple weld design have provided an expected lifetime of 6000 hours when exposed to reactor coolant conditions of 620 K and 15.9 MPa and to sixteen thermal cycles with an initial temperature of 480 K and peak temperatures ranging from 870 to 1200K. Departure from nucleate boiling (DNB) tests have indicated a DNB penalty (5 to 28% lower) during steady state operation and negligible effects during LOCA blowdown caused by the LOFT fuel rod surface thermocouple arrangement. Experience with the thermocouple design in Power Burst Facility (PBF) and LOFT nonnuclear blowdown testing has been quite satisfactory. Tests discussed here were conducted using both stainless steel and zircaloy-clad electrically heated rod in the LOFT Test Support Facility (LTSF) blowdown simulation loop

  8. Multi-species coral Sr/Ca-based sea-surface temperature reconstruction using Orbicella faveolata and Siderastrea siderea from the Florida Straits

    Science.gov (United States)

    Flannery, Jennifer A.; Richey, Julie N.; Thirumalai, Kaustubh; Poore, Richard Z.; DeLong, Kristine L.

    2017-01-01

    We present new, monthly-resolved Sr/Ca-based sea-surface temperature (SST) records from two species of massive coral, Orbicella faveolata and Siderastrea siderea, from the Dry Tortugas National Park, FL, USA (DTNP). We combine these new records with published data from three additional S. siderea coral colonies to generate a 278-year long multi-species stacked Sr/Ca-SST record from DTNP. The composite record of mean annual Sr/Ca-SST at DTNP shows pronounced decadal-scale variability with a range of 1 to 2°C. Notable cool intervals in the Sr/Ca-derived SST lasting about a decade centered at ~1845, ~1935, and ~1965 are associated with reduced summer Sr/Ca-SST (monthly maxima < 29°C), and imply a reduction in the spatial extent of the Atlantic Warm Pool (AWP). There is significant coherence between the composite DTNP Sr/Ca-SST record and the Atlantic Multidecadal Oscillation (AMO) index, with the AMO lagging Sr/Ca-SST at DTNP by 9 years. Low frequency variability in the Gulf Stream surface transport, which originates near DTNP, may provide a link for the lagged relationship between multidecadal variability at DTNP and the AMO.

  9. Surface temperature measurement of plasma facing components in tokamaks

    International Nuclear Information System (INIS)

    Amiel, Stephane

    2014-01-01

    During this PhD, the challenges on the non-intrusive surface temperature measurements of metallic plasma facing components in tokamaks are reported. Indeed, a precise material emissivity value is needed for classical infrared methods and the environment contribution has to be known particularly for low emissivities materials. Although methods have been developed to overcome these issues, they have been implemented solely for dedicated experiments. In any case, none of these methods are suitable for surface temperature measurement in tokamaks.The active pyrometry introduced in this study allows surface temperature measurements independently of reflected flux and emissivities using pulsed and modulated photothermal effect. This method has been validated in laboratory on metallic materials with reflected fluxes for pulsed and modulated modes. This experimental validation is coupled with a surface temperature variation induced by photothermal effect and temporal signal evolvement modelling in order to optimize both the heating source characteristics and the data acquisition and treatment. The experimental results have been used to determine the application range in temperature and detection wavelengths. In this context, the design of an active pyrometry system on tokamak has been completed, based on a bicolor camera for a thermography application in metallic (or low emissivity) environment.The active pyrometry method introduced in this study is a complementary technique of classical infrared methods used for thermography in tokamak environment which allows performing local and 2D surface temperature measurements independently of reflected fluxes and emissivities. (author) [fr

  10. Stratospheric Impact of Varying Sea Surface Temperatures

    Science.gov (United States)

    Newman, Paul A.; Nash, Eric R.; Nielsen, Jon E.; Waugh, Darryn; Pawson, Steven

    2004-01-01

    The Finite-Volume General Circulation Model (FVGCM) has been run in 50 year simulations with the: 1) 1949-1999 Hadley Centre sea surface temperatures (SST), and 2) a fixed annual cycle of SSTs. In this presentation we first show that the 1949-1999 FVGCM simulation produces a very credible stratosphere in comparison to an NCEP/NCAR reanalysis climatology. In particular, the northern hemisphere has numerous major and minor stratospheric warming, while the southern hemisphere has only a few over the 50-year simulation. During the northern hemisphere winter, temperatures are both warmer in the lower stratosphere and the polar vortex is weaker than is found in the mid-winter southern hemisphere. Mean temperature differences in the lower stratosphere are shown to be small (less than 2 K), and planetary wave forcing is found to be very consistent with the climatology. We then will show the differences between our varying SST simulation and the fixed SST simulation in both the dynamics and in two parameterized trace gases (ozone and methane). In general, differences are found to be small, with subtle changes in planetary wave forcing that lead to reduced temperatures in the SH and increased temperatures in the NH.

  11. Estimation of Surface Air Temperature Over Central and Eastern Eurasia from MODIS Land Surface Temperature

    Science.gov (United States)

    Shen, Suhung; Leptoukh, Gregory G.

    2011-01-01

    Surface air temperature (T(sub a)) is a critical variable in the energy and water cycle of the Earth.atmosphere system and is a key input element for hydrology and land surface models. This is a preliminary study to evaluate estimation of T(sub a) from satellite remotely sensed land surface temperature (T(sub s)) by using MODIS-Terra data over two Eurasia regions: northern China and fUSSR. High correlations are observed in both regions between station-measured T(sub a) and MODIS T(sub s). The relationships between the maximum T(sub a) and daytime T(sub s) depend significantly on land cover types, but the minimum T(sub a) and nighttime T(sub s) have little dependence on the land cover types. The largest difference between maximum T(sub a) and daytime T(sub s) appears over the barren and sparsely vegetated area during the summer time. Using a linear regression method, the daily maximum T(sub a) were estimated from 1 km resolution MODIS T(sub s) under clear-sky conditions with coefficients calculated based on land cover types, while the minimum T(sub a) were estimated without considering land cover types. The uncertainty, mean absolute error (MAE), of the estimated maximum T(sub a) varies from 2.4 C over closed shrublands to 3.2 C over grasslands, and the MAE of the estimated minimum Ta is about 3.0 C.

  12. Lake surface water temperatures of European Alpine lakes (1989-2013) based on the Advanced Very High Resolution Radiometer (AVHRR) 1 km data set

    Science.gov (United States)

    Riffler, M.; Wunderle, S.

    2014-05-01

    Lake water temperature (LWT) is an important driver of lake ecosystems and it has been identified as an indicator of climate change. Thus, the Global Climate Observing System (GCOS) lists LWT as an Essential Climate Variable (ECV). Although for some European lakes long in situ time series of LWT do exist, many lakes are not observed or only on a non-regular basis making these observations insufficient for climate monitoring. Satellite data can provide the information needed. However, only few satellite sensors offer the possibility to analyse time series which cover 25 years or more. The Advanced Very High Resolution Radiometer (AVHRR) is among these and has been flown as a heritage instrument for almost 35 years. It will be carried on for at least ten more years finally offering a unique opportunity for satellite-based climate studies. Herein we present a satellite-based lake surface water temperature (LSWT) data set for European (pre-alpine) water bodies based on the extensive AVHRR 1 km data record (1989-2013) of the Remote Sensing Research Group at the University of Bern. It has been compiled out of AVHRR/2 (NOAA-07, -09, -11, -14) and AVHRR/3 (NOAA-16, -17, -18, -19 and Metop-A) data. The high accuracy needed for climate related studies requires careful pre-processing and consideration of the atmospheric state. Especially data from NOAA-16 and prior satellites were prone to noise, e.g., due to transmission errors or fluctuations in the instrument's thermal state. This has resulted in partly corrupted thermal calibration data and may cause errors of up to several Kelvin in the final resulting LSWT. Thus, a multi-stage correction scheme has been applied to the data to minimize these artefacts. The LSWT retrieval is based on a simulation-based scheme making use of the Radiative Transfer for TOVS (RTTOV) Version 10 together with operational analysis and reanalysis data from the European Centre for Medium Range Weather Forecasts. The resulting LSWTs were

  13. Surface temperature and surface heat flux determination of the inverse heat conduction problem for a slab

    International Nuclear Information System (INIS)

    Kuroyanagi, Toshiyuki

    1983-07-01

    Based on an idea that surface conditions should be a reflection of interior temperature and interior heat flux variation as inverse as interior conditions has been determined completely by the surface temperature and/on surface heat flux as boundary conditions, a method is presented for determining the surface temperature and the surface heat flux of a solid when the temperature and heat flux at an interior point are a prescribed function of time. The method is developed by the integration of Duhumels' integral which has unknown temperature or unknown heat flux in its integrand. Specific forms of surface condition determination are developed for a sample inverse problem: slab. Ducussing the effect of a degree of avairable informations at an interior point due to damped system and the effect of variation of surface conditions on those formulations, it is shown that those formulations are capable of representing the unknown surface conditions except for small time interval followed by discontinuous change of surface conditions. The small un-resolved time interval is demonstrated by a numerical example. An evaluation method of heat flux at an interior point, which is requested by those formulations, is discussed. (author)

  14. Variability of emissivity and surface temperature over a sparsely vegetated surface

    International Nuclear Information System (INIS)

    Humes, K.S.; Kustas, W.P.; Moran, M.S.; Nichols, W.D.; Weltz, M.A.

    1994-01-01

    Radiometric surface temperatures obtained from remote sensing measurements are a function of both the physical surface temperature and the effective emissivity of the surface within the band pass of the radiometric measurement. For sparsely vegetated areas, however, a sensor views significant fractions of both bare soil and various vegetation types. In this case the radiometric response of a sensor is a function of the emissivities and kinetic temperatures of various surface elements, the proportion of those surface elements within the field of view of the sensor, and the interaction of radiation emitted from the various surface components. In order to effectively utilize thermal remote sensing data to quantify energy balance components for a sparsely vegetated area, it is important to examine the typical magnitude and degree of variability of emissivity and surface temperature for such surfaces. Surface emissivity measurements and ground and low-altitude-aircraft-based surface temperature measurements (8-13 micrometer band pass) made in conjunction with the Monsoon '90 field experiment were used to evaluate the typical variability of those quantities during the summer rainy season in a semiarid watershed. The average value for thermal band emissivity of the exposed bare soil portions of the surface was found to be approximately 0.96; the average value measured for most of the varieties of desert shrubs present was approximately 0.99. Surface composite emissivity was estimated to be approximately 0.98 for both the grass-dominated and shrub-dominated portions of the watershed. The spatial variability of surface temperature was found to be highly dependent on the spatial scale of integration for the instantaneous field of view (IFOV) of the instrument, the spatial scale of the total area under evaluation, and the time of day

  15. Climate Prediction Center (CPC) Global Land Surface Air Temperature Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A station observation-based global land monthly mean surface air temperature dataset at 0.5 0.5 latitude-longitude resolution for the period from 1948 to the present...

  16. Climate Prediction Center (CPC) Global Land Surface Air Temperature Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A station observation-based global land monthly mean surface air temperature dataset at 0.5 x 0.5 latitude-longitude resolution for the period from 1948 to the...

  17. Eye surface temperature detects stress response in budgerigars (Melopsittacus undulatus).

    Science.gov (United States)

    Ikkatai, Yuko; Watanabe, Shigeru

    2015-08-05

    Previous studies have suggested that stressors not only increase body core temperature but also body surface temperature in many animals. However, it remains unclear whether surface temperature could be used as an alternative to directly measure body core temperature, particularly in birds. We investigated whether surface temperature is perceived as a stress response in budgerigars. Budgerigars have been used as popular animal models to investigate various neural mechanisms such as visual perception, vocal learning, and imitation. Developing a new technique to understand the basic physiological mechanism would help neuroscience researchers. First, we found that cloacal temperature correlated with eye surface temperature. Second, eye surface temperature increased after handling stress. Our findings suggest that eye surface temperature is closely related to cloacal temperature and that the stress response can be measured by eye surface temperature in budgerigars.

  18. Urban pavement surface temperature. Comparison of numerical and statistical approach

    Science.gov (United States)

    Marchetti, Mario; Khalifa, Abderrahmen; Bues, Michel; Bouilloud, Ludovic; Martin, Eric; Chancibaut, Katia

    2015-04-01

    The forecast of pavement surface temperature is very specific in the context of urban winter maintenance. to manage snow plowing and salting of roads. Such forecast mainly relies on numerical models based on a description of the energy balance between the atmosphere, the buildings and the pavement, with a canyon configuration. Nevertheless, there is a specific need in the physical description and the numerical implementation of the traffic in the energy flux balance. This traffic was originally considered as a constant. Many changes were performed in a numerical model to describe as accurately as possible the traffic effects on this urban energy balance, such as tires friction, pavement-air exchange coefficient, and infrared flux neat balance. Some experiments based on infrared thermography and radiometry were then conducted to quantify the effect fo traffic on urban pavement surface. Based on meteorological data, corresponding pavement temperature forecast were calculated and were compared with fiels measurements. Results indicated a good agreement between the forecast from the numerical model based on this energy balance approach. A complementary forecast approach based on principal component analysis (PCA) and partial least-square regression (PLS) was also developed, with data from thermal mapping usng infrared radiometry. The forecast of pavement surface temperature with air temperature was obtained in the specific case of urban configurtation, and considering traffic into measurements used for the statistical analysis. A comparison between results from the numerical model based on energy balance, and PCA/PLS was then conducted, indicating the advantages and limits of each approach.

  19. Sea surface temperature as a proxy for convective gravity wave excitation: a study based on global gravity wave observations in the middle atmosphere

    Directory of Open Access Journals (Sweden)

    J. Y. Jia

    2014-11-01

    Full Text Available Absolute values of gravity wave momentum flux (GWMF deduced from satellite measurements by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER instrument and the High Resolution Dynamics Limb Sounder (HIRDLS are correlated with sea surface temperature (SST with the aim of identifying those oceanic regions for which convection is a major source of gravity waves (GWs. Our study identifies those latitude bands where high correlation coefficients indicate convective excitation with confidence. This is based on a global ray-tracing simulation, which is used to delineate the source and wind-filtering effects. Convective GWs are identified at the eastern coasts of the continents and over the warm water regions formed by the warm ocean currents, in particular the Gulf Stream and the Kuroshio. Potential contributions of tropical cyclones to the excitation of the GWs are discussed. Convective excitation can be identified well into the mid-mesosphere. In propagating upward, the centers of GWMF formed by convection shift poleward. Some indications of the main forcing regions are even shown for the upper mesosphere/lower thermosphere (MLT.

  20. Body temperature measurement in mice during acute illness: implantable temperature transponder versus surface infrared thermometry.

    Science.gov (United States)

    Mei, Jie; Riedel, Nico; Grittner, Ulrike; Endres, Matthias; Banneke, Stefanie; Emmrich, Julius Valentin

    2018-02-23

    Body temperature is a valuable parameter in determining the wellbeing of laboratory animals. However, using body temperature to refine humane endpoints during acute illness generally lacks comprehensiveness and exposes to inter-observer bias. Here we compared two methods to assess body temperature in mice, namely implanted radio frequency identification (RFID) temperature transponders (method 1) to non-contact infrared thermometry (method 2) in 435 mice for up to 7 days during normothermia and lipopolysaccharide (LPS) endotoxin-induced hypothermia. There was excellent agreement between core and surface temperature as determined by method 1 and 2, respectively, whereas the intra- and inter-subject variation was higher for method 2. Nevertheless, using machine learning algorithms to determine temperature-based endpoints both methods had excellent accuracy in predicting death as an outcome event. Therefore, less expensive and cumbersome non-contact infrared thermometry can serve as a reliable alternative for implantable transponder-based systems for hypothermic responses, although requiring standardization between experimenters.

  1. Long-term changes in sea surface temperatures

    International Nuclear Information System (INIS)

    Parker, D.E.

    1994-01-01

    Historical observations of sea surface temperature since 1856 have been improved by applying corrections to compensate for the predominant use of uninsulated or partly insulated buckets until the Second World War. There are large gaps in coverage in the late nineteenth century and around the two world wars, but a range of statistical techniques suggest that these gaps do not severely prejudice estimates of global and regional climatic change. Nonetheless, to improve the analysis on smaller scales, many unused historical data are to be digitized and incorporated. For recent years, satellite-based sea surface temperatures have improved the coverage, after adjustments for their biases relative to in situ data. An initial version of a nominally globally complete sea ice and interpolated sea surface temperature data set, beginning in 1871, has been created for use in numerical simulations of recent climate. Long time series of corrected regional, hemispheric, and global sea surface temperatures are mostly consistent with corresponding night marine air temperature series, and confirm the regionally specific climatic changes portrayed in the Scientific Assessments of the intergovernmental Panel on Climate Change. The observations also show an El Nino-like oscillation on bidecadal and longer time scales

  2. Merged Land and Ocean Surface Temperature, Version 3.5

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The historical Merged Land-Ocean Surface Temperature Analysis (MLOST) is derived from two independent analyses, an Extended Reconstructed Sea Surface Temperature...

  3. NOAA Extended Reconstructed Sea Surface Temperature (ERSST), Version 5

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Extended Reconstructed Sea Surface Temperature (ERSST) dataset is a global monthly sea surface temperature dataset derived from the International...

  4. NOAA Global Surface Temperature Dataset, Version 4.0

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Global Surface Temperature Dataset (NOAAGlobalTemp) is derived from two independent analyses: the Extended Reconstructed Sea Surface Temperature (ERSST)...

  5. Surface layer temperature inversion in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Gopalakrishna, V.V.; Muraleedharan, P.M.; Reddy, G.V.; Araligidad, N.; Shenoy, Shrikant

    Surface layer temperature inversion occurring in the Bay of Bengal has been addressed. Hydrographic data archived in the Indian Oceanographic Data Center are used to understand various aspects of the temperature inversion of surface layer in the Bay...

  6. Extended Reconstructed Sea Surface Temperature (ERSST), Version 4

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Extended Reconstructed Sea Surface Temperature (ERSST) dataset is a global monthly sea surface temperature analysis on a 2x2 degree grid derived from the...

  7. Evaluation of MODIS Land Surface Temperature with In Situ Snow Surface Temperature from CREST-SAFE

    Science.gov (United States)

    Perez Diaz, C. L.; Lakhankar, T.; Romanov, P.; Munoz, J.; Khanbilvardi, R.; Yu, Y.

    2016-12-01

    This paper presents the procedure and results of a temperature-based validation approach for the Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) product provided by the National Aeronautics and Space Administration (NASA) Terra and Aqua Earth Observing System satellites using in situ LST observations recorded at the Cooperative Remote Sensing Science and Technology Center - Snow Analysis and Field Experiment (CREST-SAFE) during the years of 2013 (January-April) and 2014 (February-April). A total of 314 day and night clear-sky thermal images, acquired by the Terra and Aqua satellites, were processed and compared to ground-truth data from CREST-SAFE with a frequency of one measurement every 3 min. Additionally, this investigation incorporated supplementary analyses using meteorological CREST-SAFE in situ variables (i.e. wind speed, cloud cover, incoming solar radiation) to study their effects on in situ snow surface temperature (T-skin) and T-air. Furthermore, a single pixel (1km2) and several spatially averaged pixels were used for satellite LST validation by increasing the MODIS window size to 5x5, 9x9, and 25x25 windows for comparison. Several trends in the MODIS LST data were observed, including the underestimation of daytime values and nighttime values. Results indicate that, although all the data sets (Terra and Aqua, diurnal and nocturnal) showed high correlation with ground measurements, day values yielded slightly higher accuracy ( 1°C), both suggesting that MODIS LST retrievals are reliable for similar land cover classes and atmospheric conditions. Results from the CREST-SAFE in situ variables' analyses indicate that T-air is commonly higher than T-skin, and that a lack of cloud cover results in: lower T-skin and higher T-air minus T-skin difference (T-diff). Additionally, the study revealed that T-diff is inversely proportional to cloud cover, wind speed, and incoming solar radiation. Increasing the MODIS window size

  8. High-Temperature Surface-Acoustic-Wave Transducer

    Science.gov (United States)

    Zhao, Xiaoliang; Tittmann, Bernhard R.

    2010-01-01

    Aircraft-engine rotating equipment usually operates at high temperature and stress. Non-invasive inspection of microcracks in those components poses a challenge for the non-destructive evaluation community. A low-profile ultrasonic guided wave sensor can detect cracks in situ. The key feature of the sensor is that it should withstand high temperatures and excite strong surface wave energy to inspect surface/subsurface cracks. As far as the innovators know at the time of this reporting, there is no existing sensor that is mounted to the rotor disks for crack inspection; the most often used technology includes fluorescent penetrant inspection or eddy-current probes for disassembled part inspection. An efficient, high-temperature, low-profile surface acoustic wave transducer design has been identified and tested for nondestructive evaluation of structures or materials. The development is a Sol-Gel bismuth titanate-based surface-acoustic-wave (SAW) sensor that can generate efficient surface acoustic waves for crack inspection. The produced sensor is very thin (submillimeter), and can generate surface waves up to 540 C. Finite element analysis of the SAW transducer design was performed to predict the sensor behavior, and experimental studies confirmed the results. One major uniqueness of the Sol-Gel bismuth titanate SAW sensor is that it is easy to implement to structures of various shapes. With a spray coating process, the sensor can be applied to surfaces of large curvatures. Second, the sensor is very thin (as a coating) and has very minimal effect on airflow or rotating equipment imbalance. Third, it can withstand temperatures up to 530 C, which is very useful for engine applications where high temperature is an issue.

  9. Estimation of land surface temperature of Kaduna metropolis ...

    African Journals Online (AJOL)

    Estimation of land surface temperature of Kaduna metropolis, Nigeria using landsat images. Isa Zaharaddeen, Ibrahim I. Baba, Ayuba Zachariah. Abstract. Understanding the spatial variation of Land Surface Temperature (LST), will be helpful in urban micro climate studies. This study estimates the land surface temperature ...

  10. A 1200 Year Alkenone-based Reconstruction of Sea Surface Temperature and Marine Productivity in the Southern California Current System from the Medieval Climate Anomaly to Present

    Science.gov (United States)

    O'Mara, N. A.; Kelly, C. S.; Herbert, T.

    2017-12-01

    Laminated sediment cores taken from the San Lazaro Basin (SLB) (25.18N, 112.66W) located off the coast of Baja California in the subtropical eastern Pacific were geochemically analyzed for alkenone and sterol biomarkers to reconstruct sea surface temperature (SST) and marine productivity from 850-1980 CE. High sedimentation rates, low bottom water dissolved oxygen, and high marine productivity in combination with the San Lazaro Basin's location within the dynamic transition zone between the tropical and subtropical eastern Pacific, make it a prime location to study variability of tropical and subtropical modes of climate variability. This study focuses on the impacts and variability of the El Niño Southern Oscillation and the Pacific Decadal Oscillation on the subtropical eastern Pacific. SST and coccolithophore productivity (n=730) for 2 mm sections of sediment corresponding to 1 measurement every 1.8 years were reconstructed using the Uk'37 unsaturation index and C37 alkenone concentration. The high resolution of this record allowed for the analysis of variability of SST and productivity on decadal timescales. Brassicasterol concentrations were calculated for a limited number of samples (n=44) to assess diatom productivity. High spectral power was found at periods of 20-30 years in SST and productivity records indicating a strong influence of the PDO on the SLB, making this the first marine based record directly relevant to PDO reconstructions that continuously spans the last millennium. Cool and productive (warm and less productive) waters were observed in the southern California Current in the Medieval Climate Anomaly 900-1200 CE (Little Ice Age 1400-1800 CE) supporting previous reconstructions that warmer (cooler) SST are linked to both reduced (enhanced) phytoplankton productivity. Additionally, cool (warm) SST were also associated with dry (wet) conditions in the American Southwest indicating that changes in the PDO has had a significant impact on drought

  11. estimation of land surface temperature of kaduna metropolis, nigeria

    African Journals Online (AJOL)

    Zaharaddeen et. al

    Land surface temperature can provide noteworthy information about the surface ... modelling the surface energy balance (Kalma, et al., 2008; ... Landsat, in addition some of the Landsat data have cloud cover and ..... The Impact Of Urban.

  12. An operational analysis of Lake Surface Water Temperature

    Directory of Open Access Journals (Sweden)

    Emma K. Fiedler

    2014-07-01

    Full Text Available Operational analyses of Lake Surface Water Temperature (LSWT have many potential uses including improvement of numerical weather prediction (NWP models on regional scales. In November 2011, LSWT was included in the Met Office Operational Sea Surface Temperature and Ice Analysis (OSTIA product, for 248 lakes globally. The OSTIA analysis procedure, which has been optimised for oceans, has also been used for the lakes in this first version of the product. Infra-red satellite observations of lakes and in situ measurements are assimilated. The satellite observations are based on retrievals optimised for Sea Surface Temperature (SST which, although they may introduce inaccuracies into the LSWT data, are currently the only near-real-time information available. The LSWT analysis has a global root mean square difference of 1.31 K and a mean difference of 0.65 K (including a cool skin effect of 0.2 K compared to independent data from the ESA ARC-Lake project for a 3-month period (June to August 2009. It is demonstrated that the OSTIA LSWT is an improvement over the use of climatology to capture the day-to-day variation in global lake surface temperatures.

  13. Characterizing the Spatio-Temporal Pattern of Land Surface Temperature through Time Series Clustering: Based on the Latent Pattern and Morphology

    Directory of Open Access Journals (Sweden)

    Huimin Liu

    2018-04-01

    Full Text Available Land Surface Temperature (LST is a critical component to understand the impact of urbanization on the urban thermal environment. Previous studies were inclined to apply only one snapshot to analyze the pattern and dynamics of LST without considering the non-stationarity in the temporal domain, or focus on the diurnal, seasonal, and annual pattern analysis of LST which has limited support for the understanding of how LST varies with the advancing of urbanization. This paper presents a workflow to extract the spatio-temporal pattern of LST through time series clustering by focusing on the LST of Wuhan, China, from 2002 to 2017 with a 3-year time interval with 8-day MODerate-resolution Imaging Spectroradiometer (MODIS satellite image products. The Latent pattern of LST (LLST generated by non-parametric Multi-Task Gaussian Process Modeling (MTGP and the Multi-Scale Shape Index (MSSI which characterizes the morphology of LLST are coupled for pattern recognition. Specifically, spatio-temporal patterns are discovered after the extraction of spatial patterns conducted by the incorporation of k -means and the Back-Propagation neural networks (BP-Net. The spatial patterns of the 6 years form a basic understanding about the corresponding temporal variances. For spatio-temporal pattern recognition, LLSTs and MSSIs of the 6 years are regarded as geo-referenced time series. Multiple algorithms including traditional k -means with Euclidean Distance (ED, shape-based k -means with the constrained Dynamic Time Warping ( c DTW distance measure, and the Dynamic Time Warping Barycenter Averaging (DBA centroid computation method ( k - c DBA and k -shape are applied. Ten external indexes are employed to evaluate the performance of the three algorithms and reveal k - c DBA as the optimal time series clustering algorithm for our study. The study area is divided into 17 geographical time series clusters which respectively illustrate heterogeneous temporal dynamics of LST

  14. Precambrian Surface Temperatures and Molecular Phylogeny

    Science.gov (United States)

    Schwartzman, David; Lineweaver, Charles H.

    2004-06-01

    The timing of emergence of major organismal groups is consistent with the climatic temperature being equal to their upper temperature limit of growth (T_{max}), implying a temperature constraint on the evolution of each group, with the climatic temperature inferred from the oxygen isotope record of marine cherts. Support for this constraint comes from the correlation of T_{max} with the rRNA molecular phylogenetic distance from the last common ancestor (LCA) for both thermophilic Archaea and Bacteria. In particular, this correlation for hyperthermophilic Archaea suggests a climatic temperature of about 120°C at the time of the LCA, likely in the Hadean.

  15. White Dwarfs in Cataclysmic Variable Stars: Surface Temperatures and Evolution

    Directory of Open Access Journals (Sweden)

    Edward M. Sion

    2012-06-01

    Full Text Available A summary is presented of what is currently known about the surface temperatures of accreting white dwarfs (WDs detected in non-magnetic and magnetic cataclysmic variables (CVs based upon synthetic spectral analyses of far ultraviolet data. A special focus is placed on WD temperatures above and below the CV period gap as a function of the orbital period, Porb. The principal uncertainty of the temperatures for the CV WDs in the Teff - Porb distribution, besides the distance to the CV, is the mass of the WD. Only in eclipsing CV systems, an area of eclipsing binary studies, which was so central to Robert H. Koch’s career, is it possible to know CV WD masses with high precision.

  16. High Predictive Skill of Global Surface Temperature a Year Ahead

    Science.gov (United States)

    Folland, C. K.; Colman, A.; Kennedy, J. J.; Knight, J.; Parker, D. E.; Stott, P.; Smith, D. M.; Boucher, O.

    2011-12-01

    We discuss the high skill of real-time forecasts of global surface temperature a year ahead issued by the UK Met Office, and their scientific background. Although this is a forecasting and not a formal attribution study, we show that the main instrumental global annual surface temperature data sets since 1891 are structured consistently with a set of five physical forcing factors except during and just after the second World War. Reconstructions use a multiple application of cross validated linear regression to minimise artificial skill allowing time-varying uncertainties in the contribution of each forcing factor to global temperature to be assessed. Mean cross validated reconstructions for the data sets have total correlations in the range 0.93-0.95,interannual correlations in the range 0.72-0.75 and root mean squared errors near 0.06oC, consistent with observational uncertainties.Three transient runs of the HadCM3 coupled model for 1888-2002 demonstrate quite similar reconstruction skill from similar forcing factors defined appropriately for the model, showing that skilful use of our technique is not confined to observations. The observed reconstructions show that the Atlantic Multidecadal Oscillation (AMO) likely contributed to the re-commencement of global warming between 1976 and 2010 and to global cooling observed immediately beforehand in 1965-1976. The slowing of global warming in the last decade is likely to be largely due to a phase-delayed response to the downturn in the solar cycle since 2001-2, with no net ENSO contribution. The much reduced trend in 2001-10 is similar in size to other weak decadal temperature trends observed since global warming resumed in the 1970s. The causes of variations in decadal trends can be mostly explained by variations in the strength of the forcing factors. Eleven real-time forecasts of global mean surface temperature for the year ahead for 2000-2010, based on broadly similar methods, provide an independent test of the

  17. Multi-Sensor Improved Sea Surface Temperature (MISST) for GODAE

    National Research Council Canada - National Science Library

    Gentemann, Chelle L; Wick, Gary A; Cummings, James; Bayler, Eric

    2004-01-01

    ...) sensors and to then demonstrate the impact of these improved sea surface temperatures (SSTs) on operational ocean models, numerical weather prediction, and tropical cyclone intensity forecasting...

  18. Effect of feed moisture, extrusion temperature and screw speed on properties of soy white flakes based aquafeed: a response surface analysis.

    Science.gov (United States)

    Singh, Sushil K; Muthukumarappan, Kasiviswanathan

    2016-04-01

    Soy white flakes (SWF) is an intermediate product during soy bean processing. It is an untoasted inexpensive product and contains around 51% of crude protein. It can be a potential source of protein to replace fish meal for developing aquafeed. The extrusion process is versatile and is used for the development of aquafeed. Our objective was to study the effects of inclusion of SWF (up to 50%) and other extrusion processing parameters such as barrel temperature and screw speed on the properties of aquafeed extrudates using a single-screw extruder. Extrudate properties, including pellet durability index, bulk density, water absorption and solubility indices and mass flow rate, were significantly (P < 0.05) affected by the process variables. SWF was the most significant variable with quadratic effects on most of the properties. Increasing temperature and screw speed resulted in increase in durability and mass flow rate of extrudates. Response surface regression models were established to correlate the properties of extrudates to the process variables. SWF was used as an alternative protein source of fish meal. Our study shows that aquafeed with high durability, lower bulk density and lower water absorption and higher solubility indices can be obtained by adding SWF up to 40%. © 2015 Society of Chemical Industry.

  19. Temperature sensitive surfaces and methods of making same

    Science.gov (United States)

    Liang, Liang [Richland, WA; Rieke, Peter C [Pasco, WA; Alford, Kentin L [Pasco, WA

    2002-09-10

    Poly-n-isopropylacrylamide surface coatings demonstrate the useful property of being able to switch charateristics depending upon temperature. More specifically, these coatings switch from being hydrophilic at low temperature to hydrophobic at high temperature. Research has been conducted for many years to better characterize and control the properties of temperature sensitive coatings. The present invention provides novel temperature sensitive coatings on articles and novel methods of making temperature sensitive coatings that are disposed on the surfaces of various articles. These novel coatings contain the reaction products of n-isopropylacrylamide and are characterized by their properties such as advancing contact angles. Numerous other characteristics such as coating thickness, surface roughness, and hydrophilic-to-hydrophobic transition temperatures are also described. The present invention includes articles having temperature-sensitve coatings with improved properties as well as improved methods for forming temperature sensitive coatings.

  20. Worldwide surface temperature trends since the mid-19th century

    International Nuclear Information System (INIS)

    Parker, D.E.; Folland, C.K.

    1990-01-01

    Sea surface temperatures (SSTs) for the period 1856 to the present have been corrected to compensate for the use of uninsulated buckets prior to the early 1940s. Trends in the corrected SST are consistent with trends in independently corrected nighttime marine air temperatures (NMAT). Global-scale patterns of variation of annual anomalies of SST and NMAT, as revealed by the first three covariance eigenvectors, are also in close agreement. The corrected SST anomalies are also compared with those of nearby coastal and island land air temperatures. Global-scale agreement is good except in the early 20th century when the land data were relatively warm by up to 0.2 C. Proposed causes are the siting of thermometers in open-sided thatched sheds in tropical regions at that time, along with a marked tendency to warm westerly atmospheric circulation over Europe in winter. Combined fields of SST and land air temperature are presented. The relative overall coldness of the late 19th century land air temperatures appears to have arisen from inner-continental and high-latitude regions, especially in winter. Combined fields do not yield full global coverage even in the 1980s, so satellite-based SST data need to be blended carefully with the ship-based observations if monitoring of global climate is to be complete

  1. Worldwide surface temperature trends since the mid-19th century

    International Nuclear Information System (INIS)

    Parker, D.E.; Folland, C.K.

    1991-01-01

    Sea surface temperatures (SSTs) for the period 1856 to the present have been corrected to compensate for the use of uninsulated buckets prior to the early 1940s. Trends in the corrected SST are consistent with trends in independently corrected nighttime marine air temperatures (NMAT). Global-scale patterns of variation of annual anomalies of SST and NMAT, as revealed by the first three covariance eigenvectors, are also in close agreement. The corrected SST anomalies are also compared with those of nearby coastal and island land air temperatures. Global-scale agreement is good except in the early 20th century when the land data were relatively warm by up to 0.2 C. Proposed causes are the siting of thermometers in open-sided thatched sheds in tropical regions at that time, along with a marked tendency to warm westerly atmospheric circulation over Europe in winter. Combined fields of SST and land air temperature are presented. The relative overall coldness of the late 19th century land air temperatures appears to have arisen from inner-continental and high-latitude regions, especially in winter. Combined fields do not yield full global coverage even in the 1980s, so satellite-based SST data need to be blended carefully with the ship-based observations if monitoring of global climate is to be complete. 32 refs.; 16 figs

  2. Surface alloying in Sn/Au(111) at elevated temperature

    Science.gov (United States)

    Sadhukhan, Pampa; Singh, Vipin Kumar; Rai, Abhishek; Bhattacharya, Kuntala; Barman, Sudipta Roy

    2018-04-01

    On the basis of x-ray photoelectron spectroscopy, we show that when Sn is deposited on Au(111) single crystal surface at a substrate temperature TS=373 K, surface alloying occurs with the formation of AuSn phase. The evolution of the surface structure and the surface morphology has been studied by low energy electron diffraction and scanning tunneling microscopy, respectively as a function of Sn coverage and substrate temperatures.

  3. Simple physical-empirical model of the precipitation distribution based on a tropical sea surface temperature threshold and the effects of climate change

    Science.gov (United States)

    Jauregui, Yakelyn R.; Takahashi, Ken

    2018-03-01

    The observed nonlinear relationship between tropical sea surface temperature (T_s) and precipitation ( P) on climate timescales, by which a threshold (T_c) must be exceeded by T_s in order for deep convection to occur, is the basis of a physical-empirical model (PEM) that we fitted to observational data and CMIP5 climate model output and used to show that, with essentially only two constant parameters (T_c and the sensitivity a_1 of P to T_s>T_c), it provides a useful first-order description of the climatological and interannual variability of the large-scale distribution of tropical P given T_s, as well as of the biases of the Global Climate Models (GCMs). A substantial limitation is its underestimation of the peak P in the convergence zones, as the necessary processes associated with the atmospheric circulation are not considered. The pattern of the intermodel correlation between the mean T_s-T_c for each GCM and the average P distribution is in agreement with the double ITCZ bias, featuring roughly zonally-symmetric off-equatorial maxima, rather than being regionally or hemispherically restricted. The inter-comparison of GCMs indicates a relationship between T_c with the near-equatorial low-level (850 hPa) tropospheric temperature, consistent with the interpretation that it is a measure of the convective inhibition (CIN). The underestimation of T_c is linked to the cold free tropospheric bias in the GCMs. However, the discrepancy among the observational datasets is a limitation for assessing the GCM biases from the PEM framework quantitatively. Under the RCP4.5 climate change scenario, T_c increases slightly more than the mean tropical T_s, implying a stabilizing trend consistent with the amplified free tropospheric warming relative to the surface. However, since a_1 increases by 10-50%/°C with the surface warming, its effect dominates and results in generally positive precipitation change (Δ P) in the equatorial regions. In the equatorial eastern

  4. Do Aphids Alter Leaf Surface Temperature Patterns During Early Infestation?

    Directory of Open Access Journals (Sweden)

    Thomas Cahon

    2018-03-01

    Full Text Available Arthropods at the surface of plants live in particular microclimatic conditions that can differ from atmospheric conditions. The temperature of plant leaves can deviate from air temperature, and leaf temperature influences the eco-physiology of small insects. The activity of insects feeding on leaf tissues, may, however, induce changes in leaf surface temperatures, but this effect was only rarely demonstrated. Using thermography analysis of leaf surfaces under controlled environmental conditions, we quantified the impact of presence of apple green aphids on the temperature distribution of apple leaves during early infestation. Aphids induced a slight change in leaf surface temperature patterns after only three days of infestation, mostly due to the effect of aphids on the maximal temperature that can be found at the leaf surface. Aphids may induce stomatal closure, leading to a lower transpiration rate. This effect was local since aphids modified the configuration of the temperature distribution over leaf surfaces. Aphids were positioned at temperatures near the maximal leaf surface temperatures, thus potentially experiencing the thermal changes. The feedback effect of feeding activity by insects on their host plant can be important and should be quantified to better predict the response of phytophagous insects to environmental changes.

  5. The EUSTACE project: delivering global, daily information on surface air temperature

    Science.gov (United States)

    Ghent, D.; Rayner, N. A.

    2017-12-01

    Day-to-day variations in surface air temperature affect society in many ways; however, daily surface air temperature measurements are not available everywhere. A global daily analysis cannot be achieved with measurements made in situ alone, so incorporation of satellite retrievals is needed. To achieve this, in the EUSTACE project (2015-2018, https://www.eustaceproject.eu) we have developed an understanding of the relationships between traditional (land and marine) surface air temperature measurements and retrievals of surface skin temperature from satellite measurements, i.e. Land Surface Temperature, Ice Surface Temperature, Sea Surface Temperature and Lake Surface Water Temperature. Here we discuss the science needed to produce a fully-global daily analysis (or ensemble of analyses) of surface air temperature on the centennial scale, integrating different ground-based and satellite-borne data types. Information contained in the satellite retrievals is used to create globally-complete fields in the past, using statistical models of how surface air temperature varies in a connected way from place to place. This includes developing new "Big Data" analysis methods as the data volumes involved are considerable. We will present recent progress along this road in the EUSTACE project, i.e.: • identifying inhomogeneities in daily surface air temperature measurement series from weather stations and correcting for these over Europe; • estimating surface air temperature over all surfaces of Earth from surface skin temperature retrievals; • using new statistical techniques to provide information on higher spatial and temporal scales than currently available, making optimum use of information in data-rich eras. Information will also be given on how interested users can become involved.

  6. High temperature steam oxidation of Al3Ti-based alloys for the oxidation-resistant surface layer on Zr fuel claddings

    International Nuclear Information System (INIS)

    Park, Jeong-Yong; Kim, Il-Hyun; Jung, Yang-Il; Kim, Hyun-Gil; Park, Dong-Jun; Choi, Byung-Kwon

    2013-01-01

    We investigated the feasibility to apply Al 3 Ti-based alloys as the surface layer for improving the oxidation resistance of Zr fuel claddings under accident conditions. Two types of Al 3 Ti-based alloys with the compositions of Al–25Ti–10Cr and Al–21Ti–23Cr in atomic percent were prepared by arc-melting followed by homogenization annealing at 1423 K for 48 h. Al–25Ti–10Cr alloy showed an L1 2 quasi-single phase microstructure with a lot of needle-shaped minor phase and pores. Al–21Ti–23Cr alloy consisted of an L1 2 matrix and Cr 2 Al as the second phase. Al 3 Ti-based alloys showed an extremely low oxidation rate in a 1473 K steam for up to 7200 s when compared to Zircaloy-4. Both alloys exhibited almost the same oxidation rate in the early stage of oxidation, but Al–25Ti–10Cr showed a little lower oxidation rate after 4000 s than Al–21Ti–23Cr. The difference in the oxidation rate between two types of Al 3 Ti-based alloys was too marginal to distinguish the oxidation behavior of each alloy. The resultant oxide exhibited almost the same characteristics in both alloys even though the microstructure was explicitly distinguished from each other. The crystal structure of the oxide formed up to 2000 s was identified as Al 2 O 3 in both alloys. The oxide morphology consisted of columnar grains whose length was almost identical to the average oxide thickness. On the basis of the results obtained, it is considered that Al 3 Ti-based alloy is one of the promising candidates for the oxidation-resistant surface layer on Zr fuel claddings

  7. Validation of Land Surface Temperature from Sentinel-3

    Science.gov (United States)

    Ghent, D.

    2017-12-01

    One of the main objectives of the Sentinel-3 mission is to measure sea- and land-surface temperature with high-end accuracy and reliability in support of environmental and climate monitoring in an operational context. Calibration and validation are thus key criteria for operationalization within the framework of the Sentinel-3 Mission Performance Centre (S3MPC). Land surface temperature (LST) has a long heritage of satellite observations which have facilitated our understanding of land surface and climate change processes, such as desertification, urbanization, deforestation and land/atmosphere coupling. These observations have been acquired from a variety of satellite instruments on platforms in both low-earth orbit and in geostationary orbit. Retrieval accuracy can be a challenge though; surface emissivities can be highly variable owing to the heterogeneity of the land, and atmospheric effects caused by the presence of aerosols and by water vapour absorption can give a bias to the underlying LST. As such, a rigorous validation is critical in order to assess the quality of the data and the associated uncertainties. Validation of the level-2 SL_2_LST product, which became freely available on an operational basis from 5th July 2017 builds on an established validation protocol for satellite-based LST. This set of guidelines provides a standardized framework for structuring LST validation activities. The protocol introduces a four-pronged approach which can be summarised thus: i) in situ validation where ground-based observations are available; ii) radiance-based validation over sites that are homogeneous in emissivity; iii) intercomparison with retrievals from other satellite sensors; iv) time-series analysis to identify artefacts on an interannual time-scale. This multi-dimensional approach is a necessary requirement for assessing the performance of the LST algorithm for the Sea and Land Surface Temperature Radiometer (SLSTR) which is designed around biome-based

  8. High Temperature Surface Parameters for Solar Power

    National Research Council Canada - National Science Library

    Butler, C. F; Jenkins, R. J; Rudkin, R. L; Laughridge, F. I

    1960-01-01

    ... at a given distance from the sun. Thermal conversion efficiencies with a concentration ratio of 50 have been computed for each surface when exposed to solar radiation at the Earth's mean orbital radius...

  9. Predicting monsoon rainfall and pressure indices from sea surface temperature

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    The relationship between the sea surface temperature (SST) in the Indian Ocean and monsoon rainfall has been examined by using 21 years data set (1967-87) of MOHSST.6 (Met. Office Historical Sea Surface Temperature data set, obtained from U.K. Met...

  10. Recent trends in sea surface temperature off Mexico

    NARCIS (Netherlands)

    Lluch-Cota, S.E.; Tripp-Valdéz, M.; Lluch-Cota, D.B.; Lluch-Belda, D.; Verbesselt, J.; Herrera-Cervantes, H.; Bautista-Romero, J.

    2013-01-01

    Changes in global mean sea surface temperature may have potential negative implications for natural and socioeconomic systems; however, measurements to predict trends in different regions have been limited and sometimes contradictory. In this study, an assessment of sea surface temperature change

  11. Direct evaluation of transient surface temperatures and heat fluxes

    International Nuclear Information System (INIS)

    Axford, R.A.

    1975-08-01

    Evaluations of transient surface temperatures resulting from the absorption of radiation are required in laser fusion reactor systems studies. A general method for the direct evaluation of transient surface temperatures and heat fluxes on the boundaries of bounded media is developed by constructing fundamental solutions of the scalar Helmholtz equation and performing certain elementary integrations

  12. High Efficiency, High Temperature Foam Core Heat Exchanger for Fission Surface Power Systems, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Fission-based power systems with power levels of 30 to ≥100 kWe will be needed for planetary surface bases. Development of high temperature, high efficiency heat...

  13. Outdoor surface temperature measurement: ground truth or lie?

    Science.gov (United States)

    Skauli, Torbjorn

    2004-08-01

    Contact surface temperature measurement in the field is essential in trials of thermal imaging systems and camouflage, as well as for scene modeling studies. The accuracy of such measurements is challenged by environmental factors such as sun and wind, which induce temperature gradients around a surface sensor and lead to incorrect temperature readings. In this work, a simple method is used to test temperature sensors under conditions representative of a surface whose temperature is determined by heat exchange with the environment. The tested sensors are different types of thermocouples and platinum thermistors typically used in field trials, as well as digital temperature sensors. The results illustrate that the actual measurement errors can be much larger than the specified accuracy of the sensors. The measurement error typically scales with the difference between surface temperature and ambient air temperature. Unless proper care is taken, systematic errors can easily reach 10% of this temperature difference, which is often unacceptable. Reasonably accurate readings are obtained using a miniature platinum thermistor. Thermocouples can perform well on bare metal surfaces if the connection to the surface is highly conductive. It is pointed out that digital temperature sensors have many advantages for field trials use.

  14. Measurement of surface temperature and emissivity by a multitemperature method for Fourier-transform infrared spectrometers

    DEFF Research Database (Denmark)

    Clausen, Sønnik; Morgenstjerne, Axel; Rathmann, Ole

    1996-01-01

    Surface temperatures are estimated with high precision based on a multitemperature method for Fourier-transform spectrometers. The method is based on Planck's radiation law and a nonlinear least-squares fitting algorithm applied to two or more spectra at different sample temperatures and a single...... of blackbody sources are estimated with an uncertainty of 0.2-2 K. The method is demonstrated for measuring the spectral emissivity of a brass specimen and an oxidized nickel specimen. (C) 1996 Optical Society of America...... measurement at a known sample temperature, for example, at ambient temperature. The temperature of the sample surface can be measured rather easily at ambient temperature. The spectrum at ambient temperature is used to eliminate background effects from spectra as measured at other surface temperatures...

  15. Online Global Land Surface Temperature Estimation from Landsat

    Directory of Open Access Journals (Sweden)

    David Parastatidis

    2017-11-01

    Full Text Available This study explores the estimation of land surface temperature (LST for the globe from Landsat 5, 7 and 8 thermal infrared sensors, using different surface emissivity sources. A single channel algorithm is used for consistency among the estimated LST products, whereas the option of using emissivity from different sources provides flexibility for the algorithm’s implementation to any area of interest. The Google Earth Engine (GEE, an advanced earth science data and analysis platform, allows the estimation of LST products for the globe, covering the time period from 1984 to present. To evaluate the method, the estimated LST products were compared against two reference datasets: (a LST products derived from ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer, as higher-level products based on the temperature-emissivity separation approach; (b Landsat LST data that have been independently produced, using different approaches. An overall RMSE (root mean square error of 1.52 °C was observed and it was confirmed that the accuracy of the LST product is dependent on the emissivity; different emissivity sources provided different LST accuracies, depending on the surface cover. The LST products, for the full Landsat 5, 7 and 8 archives, are estimated “on-the-fly” and are available on-line via a web application.

  16. Global surface temperature in relation to northeast monsoon rainfall ...

    Indian Academy of Sciences (India)

    is observed that the meridional gradient in surface air temperature anomalies between Europe and ... Surface air tempera- ture is one of the factors that influence monsoon variability. The distribution of surface air temper- ature over land and sea determines the locations ..... Asia, north Indian Ocean, northeast Russia and.

  17. Low-temperature plasma techniques in surface modification of biomaterials

    International Nuclear Information System (INIS)

    Feng Xiangfen; Xie Hankun; Zhang Jing

    2002-01-01

    Since synthetic polymers usually can not meet the biocompatibility and bio-functional demands of the human body, surface treatment is a prerequisite for them to be used as biomaterials. A very effective surface modification method, plasma treatment, is introduced. By immobilizing the bio-active molecules with low temperature plasma, polymer surfaces can be modified to fully satisfy the requirements of biomaterials

  18. The effects of sea surface temperature gradients on surface turbulent fluxes

    Science.gov (United States)

    Steffen, John

    A positive correlation between sea surface temperature (SST) and wind stress perturbation near strong SST gradients (DeltaSST) has been observed in different parts of the world ocean, such as the Gulf Stream in the North Atlantic and the Kuroshio Extension east of Japan. These changes in winds and SSTs can modify near-surface stability, surface stress, and latent and sensible heat fluxes. In general, these small scale processes are poorly modeled in Numerical Weather Prediction (NWP) and climate models. Failure to account for these air--sea interactions produces inaccurate values of turbulent fluxes, and therefore a misrepresentation of the energy, moisture, and momentum budgets. Our goal is to determine the change in these surface turbulent fluxes due to overlooking the correlated variability in winds, SSTs, and related variables. To model these air--sea interactions, a flux model was forced with and without SST--induced changes to the surface wind fields. The SST modification to the wind fields is based on a baroclinic argument as implemented by the University of Washington Planetary Boundary-Layer (UWPBL) model. Other input parameters include 2-m air temperature, 2-m dew point temperature, surface pressure (all from ERA--interim), and Reynolds Daily Optimum Interpolation Sea Surface Temperature (OISST). Flux model runs are performed every 6 hours starting in December 2002 and ending in November 2003. From these model outputs, seasonal, monthly, and daily means of the difference between DeltaSST and no DeltaSST effects on sensible heat flux (SHF), latent heat flux (LHF), and surface stress are calculated. Since the greatest impacts occur during the winter season, six additional December-January-February (DJF) seasons were analyzed for 1987--1990 and 1999--2002. The greatest differences in surface turbulent fluxes are concentrated near strong SST fronts associated with the Gulf Stream and Kuroshio Extension. On average, 2002---2003 DJF seasonal differences in SHF

  19. A Novel Hybrid Data-Driven Model for Daily Land Surface Temperature Forecasting Using Long Short-Term Memory Neural Network Based on Ensemble Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Xike Zhang

    2018-05-01

    Full Text Available Daily land surface temperature (LST forecasting is of great significance for application in climate-related, agricultural, eco-environmental, or industrial studies. Hybrid data-driven prediction models using Ensemble Empirical Mode Composition (EEMD coupled with Machine Learning (ML algorithms are useful for achieving these purposes because they can reduce the difficulty of modeling, require less history data, are easy to develop, and are less complex than physical models. In this article, a computationally simple, less data-intensive, fast and efficient novel hybrid data-driven model called the EEMD Long Short-Term Memory (LSTM neural network, namely EEMD-LSTM, is proposed to reduce the difficulty of modeling and to improve prediction accuracy. The daily LST data series from the Mapoling and Zhijaing stations in the Dongting Lake basin, central south China, from 1 January 2014 to 31 December 2016 is used as a case study. The EEMD is firstly employed to decompose the original daily LST data series into many Intrinsic Mode Functions (IMFs and a single residue item. Then, the Partial Autocorrelation Function (PACF is used to obtain the number of input data sample points for LSTM models. Next, the LSTM models are constructed to predict the decompositions. All the predicted results of the decompositions are aggregated as the final daily LST. Finally, the prediction performance of the hybrid EEMD-LSTM model is assessed in terms of the Mean Square Error (MSE, Mean Absolute Error (MAE, Mean Absolute Percentage Error (MAPE, Root Mean Square Error (RMSE, Pearson Correlation Coefficient (CC and Nash-Sutcliffe Coefficient of Efficiency (NSCE. To validate the hybrid data-driven model, the hybrid EEMD-LSTM model is compared with the Recurrent Neural Network (RNN, LSTM and Empirical Mode Decomposition (EMD coupled with RNN, EMD-LSTM and EEMD-RNN models, and their comparison results demonstrate that the hybrid EEMD-LSTM model performs better than the other

  20. A Novel Hybrid Data-Driven Model for Daily Land Surface Temperature Forecasting Using Long Short-Term Memory Neural Network Based on Ensemble Empirical Mode Decomposition.

    Science.gov (United States)

    Zhang, Xike; Zhang, Qiuwen; Zhang, Gui; Nie, Zhiping; Gui, Zifan; Que, Huafei

    2018-05-21

    Daily land surface temperature (LST) forecasting is of great significance for application in climate-related, agricultural, eco-environmental, or industrial studies. Hybrid data-driven prediction models using Ensemble Empirical Mode Composition (EEMD) coupled with Machine Learning (ML) algorithms are useful for achieving these purposes because they can reduce the difficulty of modeling, require less history data, are easy to develop, and are less complex than physical models. In this article, a computationally simple, less data-intensive, fast and efficient novel hybrid data-driven model called the EEMD Long Short-Term Memory (LSTM) neural network, namely EEMD-LSTM, is proposed to reduce the difficulty of modeling and to improve prediction accuracy. The daily LST data series from the Mapoling and Zhijaing stations in the Dongting Lake basin, central south China, from 1 January 2014 to 31 December 2016 is used as a case study. The EEMD is firstly employed to decompose the original daily LST data series into many Intrinsic Mode Functions (IMFs) and a single residue item. Then, the Partial Autocorrelation Function (PACF) is used to obtain the number of input data sample points for LSTM models. Next, the LSTM models are constructed to predict the decompositions. All the predicted results of the decompositions are aggregated as the final daily LST. Finally, the prediction performance of the hybrid EEMD-LSTM model is assessed in terms of the Mean Square Error (MSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), Root Mean Square Error (RMSE), Pearson Correlation Coefficient (CC) and Nash-Sutcliffe Coefficient of Efficiency (NSCE). To validate the hybrid data-driven model, the hybrid EEMD-LSTM model is compared with the Recurrent Neural Network (RNN), LSTM and Empirical Mode Decomposition (EMD) coupled with RNN, EMD-LSTM and EEMD-RNN models, and their comparison results demonstrate that the hybrid EEMD-LSTM model performs better than the other five

  1. Forecasting experiments of a dynamical-statistical model of the sea surface temperature anomaly field based on the improved self-memorization principle

    Science.gov (United States)

    Hong, Mei; Chen, Xi; Zhang, Ren; Wang, Dong; Shen, Shuanghe; Singh, Vijay P.

    2018-04-01

    With the objective of tackling the problem of inaccurate long-term El Niño-Southern Oscillation (ENSO) forecasts, this paper develops a new dynamical-statistical forecast model of the sea surface temperature anomaly (SSTA) field. To avoid single initial prediction values, a self-memorization principle is introduced to improve the dynamical reconstruction model, thus making the model more appropriate for describing such chaotic systems as ENSO events. The improved dynamical-statistical model of the SSTA field is used to predict SSTA in the equatorial eastern Pacific and during El Niño and La Niña events. The long-term step-by-step forecast results and cross-validated retroactive hindcast results of time series T1 and T2 are found to be satisfactory, with a Pearson correlation coefficient of approximately 0.80 and a mean absolute percentage error (MAPE) of less than 15 %. The corresponding forecast SSTA field is accurate in that not only is the forecast shape similar to the actual field but also the contour lines are essentially the same. This model can also be used to forecast the ENSO index. The temporal correlation coefficient is 0.8062, and the MAPE value of 19.55 % is small. The difference between forecast results in spring and those in autumn is not high, indicating that the improved model can overcome the spring predictability barrier to some extent. Compared with six mature models published previously, the present model has an advantage in prediction precision and length, and is a novel exploration of the ENSO forecast method.

  2. Recent Development on the NOAA's Global Surface Temperature Dataset

    Science.gov (United States)

    Zhang, H. M.; Huang, B.; Boyer, T.; Lawrimore, J. H.; Menne, M. J.; Rennie, J.

    2016-12-01

    Global Surface Temperature (GST) is one of the most widely used indicators for climate trend and extreme analyses. A widely used GST dataset is the NOAA merged land-ocean surface temperature dataset known as NOAAGlobalTemp (formerly MLOST). The NOAAGlobalTemp had recently been updated from version 3.5.4 to version 4. The update includes a significant improvement in the ocean surface component (Extended Reconstructed Sea Surface Temperature or ERSST, from version 3b to version 4) which resulted in an increased temperature trends in recent decades. Since then, advancements in both the ocean component (ERSST) and land component (GHCN-Monthly) have been made, including the inclusion of Argo float SSTs and expanded EOT modes in ERSST, and the use of ISTI databank in GHCN-Monthly. In this presentation, we describe the impact of those improvements on the merged global temperature dataset, in terms of global trends and other aspects.

  3. Performance analysis of PV panel under varying surface temperature

    Directory of Open Access Journals (Sweden)

    Kumar Tripathi Abhishek

    2018-01-01

    Full Text Available The surface temperature of PV panel has an adverse impact on its performance. The several electrical parameters of PV panel, such as open circuit voltage, short circuit current, power output and fill factor depends on the surface temperature of PV panel. In the present study, an experimental work was carried out to investigate the influence of PV panel surface temperature on its electrical parameters. The results obtained from this experimental study show a significant reduction in the performance of PV panel with an increase in panel surface temperature. A 5W PV panel experienced a 0.4% decrease in open circuit voltage for every 1°C increase in panel surface temperature. Similarly, there was 0.6% and 0.32% decrease in maximum power output and in fill factor, respectively, for every 1°C increase in panel surface temperature. On the other hand, the short circuit current increases with the increase in surface temperature at the rate of 0.09%/°C.

  4. Remote sensing of land surface temperature: The directional viewing effect

    International Nuclear Information System (INIS)

    Smith, J.A.; Schmugge, T.J.; Ballard, J.R. Jr.

    1997-01-01

    Land Surface Temperature (LST) is an important parameter in understanding global environmental change because it controls many of the underlying processes in the energy budget at the surface and heat and water transport between the surface and the atmosphere. The measurement of LST at a variety of spatial and temporal scales and extension to global coverage requires remote sensing means to achieve these goals. Land surface temperature and emissivity products are currently being derived from satellite and aircraft remote sensing data using a variety of techniques to correct for atmospheric effects. Implicit in the commonly employed approaches is the assumption of isotropy in directional thermal infrared exitance. The theoretical analyses indicate angular variations in apparent infrared temperature will typically yield land surface temperature errors ranging from 1 to 4 C unless corrective measures are applied

  5. High-frequency fluctuations of surface temperatures in an urban environment

    Science.gov (United States)

    Christen, Andreas; Meier, Fred; Scherer, Dieter

    2012-04-01

    This study presents an attempt to resolve fluctuations in surface temperatures at scales of a few seconds to several minutes using time-sequential thermography (TST) from a ground-based platform. A scheme is presented to decompose a TST dataset into fluctuating, high-frequency, and long-term mean parts. To demonstrate the scheme's application, a set of four TST runs (day/night, leaves-on/leaves-off) recorded from a 125-m-high platform above a complex urban environment in Berlin, Germany is used. Fluctuations in surface temperatures of different urban facets are measured and related to surface properties (material and form) and possible error sources. A number of relationships were found: (1) Surfaces with surface temperatures that were significantly different from air temperature experienced the highest fluctuations. (2) With increasing surface temperature above (below) air temperature, surface temperature fluctuations experienced a stronger negative (positive) skewness. (3) Surface materials with lower thermal admittance (lawns, leaves) showed higher fluctuations than surfaces with high thermal admittance (walls, roads). (4) Surface temperatures of emerged leaves fluctuate more compared to trees in a leaves-off situation. (5) In many cases, observed fluctuations were coherent across several neighboring pixels. The evidence from (1) to (5) suggests that atmospheric turbulence is a significant contributor to fluctuations. The study underlines the potential of using high-frequency thermal remote sensing in energy balance and turbulence studies at complex land-atmosphere interfaces.

  6. Patellar Skin Surface Temperature by Thermography Reflects Knee Osteoarthritis Severity

    Directory of Open Access Journals (Sweden)

    Anna E. Denoble

    2010-01-01

    Full Text Available Background Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA. Methods A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. Results The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50–0.72 for the various regions of interest in Controls. Cutaneous temperature of the patella (knee cap yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02. Conclusion The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage.

  7. Patellar skin surface temperature by thermography reflects knee osteoarthritis severity.

    Science.gov (United States)

    Denoble, Anna E; Hall, Norine; Pieper, Carl F; Kraus, Virginia B

    2010-10-15

    Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA). A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA) participated in this study. Infrared imaging was performed with a Meditherm Med2000™ Pro infrared camera. The reproducibility of infrared imaging of the knee was evaluated through determination of intraclass correlation coefficients (ICCs) for temperature measurements from two images performed 6 months apart in Controls whose knee status was not expected to change. The average cutaneous temperature for each of five knee regions of interest was extracted using WinTes software. Knee x-rays were scored for severity of rOA based on the global Kellgren-Lawrence grading scale. The knee infrared thermal imaging procedure used here demonstrated long-term reproducibility with high ICCs (0.50-0.72 for the various regions of interest) in Controls. Cutaneous temperature of the patella (knee cap) yielded a significant correlation with severity of knee rOA (R = 0.594, P = 0.02). The skin temperature of the patellar region correlated with x-ray severity of knee OA. This method of infrared knee imaging is reliable and as an objective measure of a sign of inflammation, temperature, indicates an interrelationship of inflammation and structural knee rOA damage.

  8. Temperature profiles on the gadolinium surface during electron beam evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Ohba, Hironori; Shibata, Takemasa [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1995-03-01

    The distributions of surface temperature of gadolinium in a water-cooled copper crucible during electron beam evaporation were measured by optical pyrometry. The surface temperatures were obtained from the radiation intensity ratio of the evaporating surface and a reference light source using Planck`s law of radiation. The emitted radiation from the evaporating surface and a reference source was detected by a CCD sensor through a band pass filter of 650 nm. The measured surface temperature generally agreed with those estimated from the deposition rate and the data of the saturated vapor pressure. At high input powers, it was found that the measured value had small difference with the estimated one due to variation of the surface condition. (author).

  9. Temperature profiles on the gadolinium surface during electron beam evaporation

    International Nuclear Information System (INIS)

    Ohba, Hironori; Shibata, Takemasa

    1995-01-01

    The distributions of surface temperature of gadolinium in a water-cooled copper crucible during electron beam evaporation were measured by optical pyrometry. The surface temperatures were obtained from the radiation intensity ratio of the evaporating surface and a reference light source using Planck's law of radiation. The emitted radiation from the evaporating surface and a reference source was detected by a CCD sensor through a band pass filter of 650 nm. The measured surface temperature generally agreed with those estimated from the deposition rate and the data of the saturated vapor pressure. At high input powers, it was found that the measured value had small difference with the estimated one due to variation of the surface condition. (author)

  10. Surface stress-based biosensors.

    Science.gov (United States)

    Sang, Shengbo; Zhao, Yuan; Zhang, Wendong; Li, Pengwei; Hu, Jie; Li, Gang

    2014-01-15

    Surface stress-based biosensors, as one kind of label-free biosensors, have attracted lots of attention in the process of information gathering and measurement for the biological, chemical and medical application with the development of technology and society. This kind of biosensors offers many advantages such as short response time (less than milliseconds) and a typical sensitivity at nanogram, picoliter, femtojoule and attomolar level. Furthermore, it simplifies sample preparation and testing procedures. In this work, progress made towards the use of surface stress-based biosensors for achieving better performance is critically reviewed, including our recent achievement, the optimally circular membrane-based biosensors and biosensor array. The further scientific and technological challenges in this field are also summarized. Critical remark and future steps towards the ultimate surface stress-based biosensors are addressed. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. High-temperature morphology of stepped gold surfaces

    International Nuclear Information System (INIS)

    Bilalbegovic, G.; Tosatti, E.; Ercolessi, F.

    1992-04-01

    Molecular dynamics simulations with a classical many-body potential are used to study the high-temperature stability of stepped non-melting metal surfaces. We have studied in particular the Au(111) vicinal surfaces in the (M+1, M-1, M) family and the Au(100) vicinals in the (M, 1, 1) family. Some vicinal orientations close to the non-melting Au(111) surface become unstable close to the bulk melting temperature and facet into a mixture of crystalline (111) regions and localized surface-melted regions. On the contrary, we do not find high-temperature faceting for vicinals close to Au(100), also a non-melting surface. These (100) vicinal surfaces gradually disorder with disappearance of individual steps well below the bulk melting temperature. We have also studied the high-temperature stability of ledges formed by pairs of monoatomic steps of opposite sign on the Au(111) surface. It is found that these ledges attract each other, so that several of them merge into one larger ledge, whose edge steps then act as a nucleation site for surface melting. (author). 43 refs, 8 figs

  12. 1994 Average Monthly Sea Surface Temperature for California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA/ NASA AVHRR Oceans Pathfinder sea surface temperature data are derived from the 5-channel Advanced Very High Resolution Radiometers (AVHRR) on board the...

  13. 1993 Average Monthly Sea Surface Temperature for California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA/NASA AVHRR Oceans Pathfinder sea surface temperature data are derived from the 5-channel Advanced Very High Resolution Radiometers (AVHRR) on board the NOAA...

  14. OW NOAA AVHRR-GAC Sea-Surface Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset contains satellite-derived sea-surface temperature measurements collected by means of the Advanced Very High Resolution Radiometer - Global Area Coverage...

  15. Tropical sea surface temperatures and the earth's orbital eccentricity cycles

    Digital Repository Service at National Institute of Oceanography (India)

    Gupta, S.M.; Fernandes, A.A.; Mohan, R.

    The tropical oceanic warm pools are climatologically important regions because their sea surface temperatures (SSTs) are positively related to atmospheric greenhouse effect and the cumulonimbus-cirrus cloud anvil. Such a warm pool is also present...

  16. OW NOAA GOES-POES Sea Surface Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset contains blended satellite-derived sea-surface temperature measurements collected by means of the Geostationary Orbiting Environmental Satellites (GOES)...

  17. NOAA High-Resolution Sea Surface Temperature (SST) Analysis Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archive covers two high resolution sea surface temperature (SST) analysis products developed using an optimum interpolation (OI) technique. The analyses have a...

  18. COBE-SST2 Sea Surface Temperature and Ice

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A new sea surface temperature (SST) analysis on a centennial time scale is presented. The dataset starts in 1850 with monthly 1x1 means and is periodically updated....

  19. Global 1-km Sea Surface Temperature (G1SST)

    Data.gov (United States)

    National Aeronautics and Space Administration — JPL OurOcean Portal: A daily, global Sea Surface Temperature (SST) data set is produced at 1-km (also known as ultra-high resolution) by the JPL ROMS (Regional Ocean...

  20. Theoretical study of cathode surfaces and high-temperature superconductors

    Science.gov (United States)

    Mueller, Wolfgang

    1995-01-01

    Calculations are presented for the work functions of BaO on W, Os, Pt, and alloys of Re-W, Os-W, and Ir-W that are in excellent agreement with experiment. The observed emission enhancement for alloy relative to tungsten dispenser cathodes is attributed to properties of the substrate crystal structure and explained by the smaller depolarization of the surface dipole on hexagonal as compared to cubic substrates. For Ba and BaO on W(100), the geometry of the adsorbates has been determined by a comparison of inverse photoemission spectra with calculated densities of unoccupied states based on the fully relativistic embedded cluster approach. Results are also discussed for models of scandate cathodes and the electronic structure of oxygen on W(100) at room and elevated temperatures. A detailed comparison is made for the surface electronic structure of the high-temperature superconductor YBa2Cu3O7 as obtained with non-, quasi-, and fully relativistic cluster calculations.

  1. Afforestation in China cools local land surface temperature

    OpenAIRE

    Peng, Shu-Shi; Piao, Shilong; Zeng, Zhenzhong; Ciais, Philippe; Zhou, Liming; Li, Laurent Z. X.; Myneni, Ranga B.; Yin, Yi; Zeng, Hui

    2014-01-01

    International audience; China has the largest afforested area in the world (~62 million hectares in 2008), and these forests are carbon sinks. The climatic effect of these new forests depends on how radiant and turbulent energy fluxes over these plantations modify surface temperature. For instance, a lower albedo may cause warming, which negates the climatic benefits of carbon sequestration. Here, we used satellite measurements of land surface temperature (LST) from planted forests and adjace...

  2. SURFACE TEMPERATURES ON TITAN DURING NORTHERN WINTER AND SPRING

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, D. E.; Cottini, V.; Nixon, C. A.; Achterberg, R. K.; Flasar, F. M.; Kunde, V. G.; Romani, P. N.; Samuelson, R. E. [Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Mamoutkine, A. [ADNET Systems, Inc., Bethesda, MD 20817 (United States); Gorius, N. J. P. [The Catholic University of America, Washington, DC 20064 (United States); Coustenis, A. [Laboratoire d’Etudes Spatiales et d’Instrumentation en Astrophysique (LESIA), Observatoire de Paris, CNRS, UPMC Univ. Paris 06, Univ. Paris-Diderot, 5, place Jules Janssen, F-92195 Meudon Cedex (France); Tokano, T., E-mail: donald.e.jennings@nasa.gov [Universität zu Köln, Albertus-Magnus-Platz, D-50923 Köln (Germany)

    2016-01-01

    Meridional brightness temperatures were measured on the surface of Titan during the 2004–2014 portion of the Cassini mission by the Composite Infrared Spectrometer. Temperatures mapped from pole to pole during five two-year periods show a marked seasonal dependence. The surface temperature near the south pole over this time decreased by 2 K from 91.7 ± 0.3 to 89.7 ± 0.5 K while at the north pole the temperature increased by 1 K from 90.7 ± 0.5 to 91.5 ± 0.2 K. The latitude of maximum temperature moved from 19 S to 16 N, tracking the sub-solar latitude. As the latitude changed, the maximum temperature remained constant at 93.65 ± 0.15 K. In 2010 our temperatures repeated the north–south symmetry seen by Voyager one Titan year earlier in 1980. Early in the mission, temperatures at all latitudes had agreed with GCM predictions, but by 2014 temperatures in the north were lower than modeled by 1 K. The temperature rise in the north may be delayed by cooling of sea surfaces and moist ground brought on by seasonal methane precipitation and evaporation.

  3. SURFACE TEMPERATURES ON TITAN DURING NORTHERN WINTER AND SPRING

    International Nuclear Information System (INIS)

    Jennings, D. E.; Cottini, V.; Nixon, C. A.; Achterberg, R. K.; Flasar, F. M.; Kunde, V. G.; Romani, P. N.; Samuelson, R. E.; Mamoutkine, A.; Gorius, N. J. P.; Coustenis, A.; Tokano, T.

    2016-01-01

    Meridional brightness temperatures were measured on the surface of Titan during the 2004–2014 portion of the Cassini mission by the Composite Infrared Spectrometer. Temperatures mapped from pole to pole during five two-year periods show a marked seasonal dependence. The surface temperature near the south pole over this time decreased by 2 K from 91.7 ± 0.3 to 89.7 ± 0.5 K while at the north pole the temperature increased by 1 K from 90.7 ± 0.5 to 91.5 ± 0.2 K. The latitude of maximum temperature moved from 19 S to 16 N, tracking the sub-solar latitude. As the latitude changed, the maximum temperature remained constant at 93.65 ± 0.15 K. In 2010 our temperatures repeated the north–south symmetry seen by Voyager one Titan year earlier in 1980. Early in the mission, temperatures at all latitudes had agreed with GCM predictions, but by 2014 temperatures in the north were lower than modeled by 1 K. The temperature rise in the north may be delayed by cooling of sea surfaces and moist ground brought on by seasonal methane precipitation and evaporation

  4. Extended Reconstructed Sea Surface Temperature (ERSST) Monthly Analysis, Version 3b

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Version 3b (v3b) of the Extended Reconstructed Sea Surface Temperature (ERSST) dataset is a monthly SST analysis on a 2-degree global grid based on the International...

  5. An algorithm to retrieve Land Surface Temperature using Landsat-8 ...

    African Journals Online (AJOL)

    Ayodeji Ogunode;Mulemwa Akombelwa

    The results show temperature variation over a long period of time can be ... Remote sensing of LST using infrared radiation gives the average surface temperature of the scene ... advantage over previous Landsat series. ..... Li, F., Jackson, T. J., Kustas, W. P., Schmugge, T. J., French, A. N., Cosh, M. H. & Bindlish, R. 2004.

  6. Temporal and spatial assessments of minimum air temperature using satellite surface temperature measurements in Massachusetts, USA.

    Science.gov (United States)

    Kloog, Itai; Chudnovsky, Alexandra; Koutrakis, Petros; Schwartz, Joel

    2012-08-15

    Although meteorological stations provide accurate air temperature observations, their spatial coverage is limited and thus often insufficient for epidemiological studies. Satellite data expand spatial coverage, enhancing our ability to estimate near surface air temperature (Ta). However, the derivation of Ta from surface temperature (Ts) measured by satellites is far from being straightforward. In this study, we present a novel approach that incorporates land use regression, meteorological variables and spatial smoothing to first calibrate between Ts and Ta on a daily basis and then predict Ta for days when satellite Ts data were not available. We applied mixed regression models with daily random slopes to calibrate Moderate Resolution Imaging Spectroradiometer (MODIS) Ts data with monitored Ta measurements for 2003. Then, we used a generalized additive mixed model with spatial smoothing to estimate Ta in days with missing Ts. Out-of-sample tenfold cross-validation was used to quantify the accuracy of our predictions. Our model performance was excellent for both days with available Ts and days without Ts observations (mean out-of-sample R(2)=0.946 and R(2)=0.941 respectively). Furthermore, based on the high quality predictions we investigated the spatial patterns of Ta within the study domain as they relate to urban vs. non-urban land uses. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Analysis of Anomaly in Land Surface Temperature Using MODIS Products

    Science.gov (United States)

    Yorozu, K.; Kodama, T.; Kim, S.; Tachikawa, Y.; Shiiba, M.

    2011-12-01

    Atmosphere-land surface interaction plays a dominant role on the hydrologic cycle. Atmospheric phenomena cause variation of land surface state and land surface state can affect on atmosphereic conditions. Widely-known article related in atmospheric-land interaction was published by Koster et al. in 2004. The context of this article is that seasonal anomaly in soil moisture or soil surface temperature can affect summer precipitation generation and other atmospheric processes especially in middle North America, Sahel and south Asia. From not only above example but other previous research works, it is assumed that anomaly of surface state has a key factor. To investigate atmospheric-land surface interaction, it is necessary to analyze anomaly field in land surface state. In this study, soil surface temperature should be focused because it can be globally and continuously observed by satellite launched sensor. To land surface temperature product, MOD11C1 and MYD11C1 products which are kinds of MODIS products are applied. Both of them have 0.05 degree spatial resolution and daily temporal resolution. The difference of them is launched satellite, MOD11C1 is Terra and MYD11C1 is Aqua. MOD11C1 covers the latter of 2000 to present and MYD11C1 covers the early 2002 to present. There are unrealistic values on provided products even if daily product was already calibrated or corrected. For pre-analyzing, daily data is aggregated into 8-days data to remove irregular values for stable analysis. It was found that there are spatial and temporal distribution of 10-years average and standard deviation for each 8-days term. In order to point out extreme anomaly in land surface temperature, standard score for each 8-days term is applied. From the analysis of standard score, it is found there are large anomaly in land surface temperature around north China plain in early April 2005 and around Bangladesh in early May 2009.

  8. Long term persistence in the sea surface temperature fluctuations

    OpenAIRE

    Monetti, Roberto A.; Havlin, Shlomo; Bunde, Armin

    2002-01-01

    We study the temporal correlations in the sea surface temperature (SST) fluctuations around the seasonal mean values in the Atlantic and Pacific oceans. We apply a method that systematically overcome possible trends in the data. We find that the SST persistence, characterized by the correlation $C(s)$ of temperature fluctuations separated by a time period $s$, displays two different regimes. In the short-time regime which extends up to roughly 10 months, the temperature fluctuations display a...

  9. Surface kinetic temperature mapping using satellite spectral data in ...

    African Journals Online (AJOL)

    The result revealed that despite the limited topographic differences of the rift lakes and their proximity, the surface kinetic temperature difference is high, mainly due to groundwater and surface water fluxes. From thermal signature analysis two hot springs below the lake bed of Ziway were discovered. The various hot springs ...

  10. Temperature Dependence of Arn+ Cluster Backscattering from Polymer Surfaces: a New Method to Determine the Surface Glass Transition Temperature.

    Science.gov (United States)

    Poleunis, Claude; Cristaudo, Vanina; Delcorte, Arnaud

    2018-01-01

    In this work, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to study the intensity variations of the backscattered Ar n + clusters as a function of temperature for several amorphous polymer surfaces (polyolefins, polystyrene, and polymethyl methacrylate). For all these investigated polymers, our results show a transition of the ratio Ar 2 + /(Ar 2 + + Ar 3 + ) when the temperature is scanned from -120 °C to +125 °C (the exact limits depend on the studied polymer). This transition generally spans over a few tens of degrees and the temperature of the inflection point of each curve is always lower than the bulk glass transition temperature (T g ) reported for the considered polymer. Due to the surface sensitivity of the cluster backscattering process (several nanometers), the presented analysis could provide a new method to specifically evaluate a surface transition temperature of polymers, with the same lateral resolution as the gas cluster beam. Graphical abstract ᅟ.

  11. Tropical sea surface temperature variability near the Oligocene - Miocene boundary

    Science.gov (United States)

    Zhang, Y.; Pagani, M.

    2010-12-01

    The Oligocene/Miocene (O-M) boundary is characterized by a period of rapid and intense glaciation labeled Mi-1 at ~ 23.1 Ma. An abrupt 1.5‰ increase in the benthic foraminifera oxygen isotope composition that characterizes Mi-1 may indicate a (1) significant deep-water temperature decrease; (2) major ice-sheet expansion, or the combination of both. Current coarse Mg/Ca-based temperature estimations for the early Miocene suggests that deep-ocean temperatures were ~2°C warmer than Today [1, 2]. However, Mg/Ca based temperatures can also be influenced by changes in the carbonate ion concentration, vital effects, and diagenesis. In particular, recent evidence from mid-ocean ridge flank carbonate veins shows dramatic seawater Mg/Ca ratio changes during the Neogene (Mg/Ca from ~2.2 to 5.3, [3]), which further challenges the application of Mg/Ca thermometry. Owing to poor temperature constraints, current ice volume estimations for the late Oligocene/early Miocene range from 125% of the present-day East Antarctic Ice Sheet (EAIS) to a nearly complete collapse of the Antarctic glaciers [4]. Here we present tropical sea surface temperatures (SSTs) records based on TEX86 and alkenone UK37 near the O-M boundary. Sediment samples from Ocean Drilling Program (ODP) Site 926 in the Ceara Rise (tropical Atlantic) and Site 1148 in the South China Sea (tropical Pacific) were subject to lipid extraction, separation, gas chromatography, and liquid chromatography-mass spectrometry analysis. TEX86-based SST indicates that the tropics were ~3-4°C warmer than today and relatively stable during Mi-1. This suggests that ice-sheet dynamics, rather than temperature, might be responsible for the observed oxygen isotope changes during the O-M boundary. Further, O-M boundary averaged temperatures recorded at site 926 is ~ 0.5°C higher relative to the late Eocene from site 925 (a nearby site [5]). Given late Oligocene benthic δ18O that suggests at least 1‰ enrichment relative to the late

  12. Mechanism of high-temperature resistant water-base mud

    Energy Technology Data Exchange (ETDEWEB)

    Luo, P

    1981-01-01

    Based on experiments, the causes and laws governing the changes in the performance of water-base mud under high temperature are analyzed, and the requisites and mechanism of treating agents resisting high temperature are discussed. Ways and means are sought for inhibiting, delaying and making use of the effect of high temperature on the performance of mud, while new ideas and systematic views have been expressed on the preparation of treating agents and set-up of a high temperature resistant water-base mud system. High temperature dispersion and high temperature surface inactivation of clay in the mud, as well as their effect and method of utilization are reviewed. Subjects also touched upon include degradation and cross-linking of the high-temperature resistant treating agents, their use and effect. Based on the above, the preparation of a water-base and system capable of resisting 180 to 250/sup 0/C is recommended.

  13. All-weather Land Surface Temperature Estimation from Satellite Data

    Science.gov (United States)

    Zhou, J.; Zhang, X.

    2017-12-01

    Satellite remote sensing, including the thermal infrared (TIR) and passive microwave (MW), provides the possibility to observe LST at large scales. For better modeling the land surface processes with high temporal resolutions, all-weather LST from satellite data is desirable. However, estimation of all-weather LST faces great challenges. On the one hand, TIR remote sensing is limited to clear-sky situations; this drawback reduces its usefulness under cloudy conditions considerably, especially in regions with frequent and/or permanent clouds. On the other hand, MW remote sensing suffers from much greater thermal sampling depth (TSD) and coarser spatial resolution than TIR; thus, MW LST is generally lower than TIR LST, especially at daytime. Two case studies addressing the challenges mentioned previously are presented here. The first study is for the development of a novel thermal sampling depth correction method (TSDC) to estimate the MW LST over barren land; this second study is for the development of a feasible method to merge the TIR and MW LSTs by addressing the coarse resolution of the latter one. In the first study, the core of the TSDC method is a new formulation of the passive microwave radiation balance equation, which allows linking bulk MW radiation to the soil temperature at a specific depth, i.e. the representative temperature: this temperature is then converted to LST through an adapted soil heat conduction equation. The TSDC method is applied to the 6.9 GHz channel in vertical polarization of AMSR-E. Evaluation shows that LST estimated by the TSDC method agrees well with the MODIS LST. Validation is based on in-situ LSTs measured at the Gobabeb site in western Namibia. The results demonstrate the high accuracy of the TSDC method: it yields a root-mean squared error (RMSE) of 2 K and ignorable systematic error over barren land. In the second study, the method consists of two core processes: (1) estimation of MW LST from MW brightness temperature and (2

  14. Measuring the Surface Temperature of the Cryosphere using Remote Sensing

    Science.gov (United States)

    Hall, Dorothy K.

    2012-01-01

    A general description of the remote sensing of cryosphere surface temperatures from satellites will be provided. This will give historical information on surface-temperature measurements from space. There will also be a detailed description of measuring the surface temperature of the Greenland Ice Sheet using Moderate-Resolution Imaging Spectroradiometer (MODIS) data which will be the focus of the presentation. Enhanced melting of the Greenland Ice Sheet has been documented in recent literature along with surface-temperature increases measured using infrared satellite data since 1981. Using a recently-developed climate data record, trends in the clear-sky ice-surface temperature (IST) of the Greenland Ice Sheet have been studied using the MODIS IST product. Daily and monthly MODIS ISTs of the Greenland Ice Sheet beginning on 1 March 2000 and continuing through 31 December 2010 are now freely available to download at 6.25-km spatial resolution on a polar stereographic grid. Maps showing the maximum extent of melt for the entire ice sheet and for the six major drainage basins have been developed from the MODIS IST dataset. Twelve-year trends of the duration of the melt season on the ice sheet vary in different drainage basins with some basins melting progressively earlier over the course of the study period. Some (but not all) of the basins also show a progressively-longer duration of melt. The consistency of this IST record, with temperature and melt records from other sources will be discussed.

  15. Wintertime sea surface temperature fronts in the Taiwan Strait

    Science.gov (United States)

    Chang, Yi; Shimada, Teruhisa; Lee, Ming-An; Lu, Hsueh-Jung; Sakaida, Futoki; Kawamura, Hiroshi

    2006-12-01

    We present wintertime variations and distributions of sea surface temperature (SST) fronts in the Taiwan Strait by applying an entropy-based edge detection method to 10-year (1996-2005) satellite SST images with grid size of 0.01°. From climatological monthly mean maps of SST gradient magnitude in winter, we identify four significant SST fronts in the Taiwan Strait. The Mainland China Coastal Front is a long frontal band along the 50-m isobath near the Chinese coast. The sharp Peng-Chang Front appears along the Peng-Hu Channel and extends northward around the Chang-Yuen Ridge. The Taiwan Bank Front evolves in early winter. As the winter progresses, the front becomes broad and moves toward the Chinese coast, connecting to the Mainland China Coastal Front. The Kuroshio Front extends northeastward from the northeastern tip of Taiwan with a semicircle-shape curving along the 100-m isobath.

  16. Mathematical model of the metal mould surface temperature optimization

    Energy Technology Data Exchange (ETDEWEB)

    Mlynek, Jaroslav, E-mail: jaroslav.mlynek@tul.cz; Knobloch, Roman, E-mail: roman.knobloch@tul.cz [Department of Mathematics, FP Technical University of Liberec, Studentska 2, 461 17 Liberec, The Czech Republic (Czech Republic); Srb, Radek, E-mail: radek.srb@tul.cz [Institute of Mechatronics and Computer Engineering Technical University of Liberec, Studentska 2, 461 17 Liberec, The Czech Republic (Czech Republic)

    2015-11-30

    The article is focused on the problem of generating a uniform temperature field on the inner surface of shell metal moulds. Such moulds are used e.g. in the automotive industry for artificial leather production. To produce artificial leather with uniform surface structure and colour shade the temperature on the inner surface of the mould has to be as homogeneous as possible. The heating of the mould is realized by infrared heaters located above the outer mould surface. The conceived mathematical model allows us to optimize the locations of infrared heaters over the mould, so that approximately uniform heat radiation intensity is generated. A version of differential evolution algorithm programmed in Matlab development environment was created by the authors for the optimization process. For temperate calculations software system ANSYS was used. A practical example of optimization of heaters locations and calculation of the temperature of the mould is included at the end of the article.

  17. Mathematical model of the metal mould surface temperature optimization

    International Nuclear Information System (INIS)

    Mlynek, Jaroslav; Knobloch, Roman; Srb, Radek

    2015-01-01

    The article is focused on the problem of generating a uniform temperature field on the inner surface of shell metal moulds. Such moulds are used e.g. in the automotive industry for artificial leather production. To produce artificial leather with uniform surface structure and colour shade the temperature on the inner surface of the mould has to be as homogeneous as possible. The heating of the mould is realized by infrared heaters located above the outer mould surface. The conceived mathematical model allows us to optimize the locations of infrared heaters over the mould, so that approximately uniform heat radiation intensity is generated. A version of differential evolution algorithm programmed in Matlab development environment was created by the authors for the optimization process. For temperate calculations software system ANSYS was used. A practical example of optimization of heaters locations and calculation of the temperature of the mould is included at the end of the article

  18. Quantative determination of surface temperatures using an infrared camera

    International Nuclear Information System (INIS)

    Hsieh, C.K.; Ellingson, W.A.

    1977-01-01

    A method is presented to determine the surface-temperature distribution at each point in an infrared picture. To handle the surface reflection problem, three cases are considered that include the use of black coatings, radiation shields, and band-pass filters. For uniform irradiation on the test surface, the irradiation can be measured by using a cooled, convex mirror. Equations are derived to show that this surrounding irradiation effect can be subtracted out from the scanned radiation; thus the net radiation is related to only emission from the surface. To provide for temperature measurements over a large field, the image-processing technique is used to digitize the infrared data. The paper spells out procedures that involve the use of a computer for making point-by-point temperature calculations. Finally, a sample case is given to illustrate applications of the method. 6 figures, 1 table

  19. Symmetric scaling properties in global surface air temperature anomalies

    Science.gov (United States)

    Varotsos, Costas A.; Efstathiou, Maria N.

    2015-08-01

    We have recently suggested "long-term memory" or internal long-range correlation within the time-series of land-surface air temperature (LSAT) anomalies in both hemispheres. For example, an increasing trend in the LSAT anomalies is followed by another one at a different time in a power-law fashion. However, our previous research was mainly focused on the overall long-term persistence, while in the present study, the upward and downward scaling dynamics of the LSAT anomalies are analysed, separately. Our results show that no significant fluctuation differences were found between the increments and decrements in LSAT anomalies, over the whole Earth and over each hemisphere, individually. On the contrary, the combination of land-surface air and sea-surface water temperature anomalies seemed to cause a departure from symmetry and the increments in the land and sea surface temperature anomalies appear to be more persistent than the decrements.

  20. The potentially neglected culprit of DC surface flashover: electron migration under temperature gradients.

    Science.gov (United States)

    Li, Chuanyang; Hu, Jun; Lin, Chuanjie; He, Jinliang

    2017-06-12

    This report intends to reveal the role of electron migration and its effects in triggering direct current (DC) surface flashover under temperature gradient conditions when using epoxy-based insulating composites. The surface potential and the surface flashover voltage are both measured using insulators that are bridged between two thermo-regulated electrodes. The space charge injection and migration properties under different temperature are detected. The results show that the surface potential rises significantly because of electron migration near the high voltage (HV) electrode under high temperature conditions, thus creating an "analogous ineffective region". The expansion of this "analogous ineffective region" results in most of the voltage drop occurring near the ground electrode, which serves as an important factor triggering positive streamers across the insulation surface. This work is helpful in understanding of DC surface flashover mechanism from a new perspective and also has important significance in design of a suitable DC insulator to avoid surface flashover problem.

  1. Determination of Optimum Viewing Angles for the Angular Normalization of Land Surface Temperature over Vegetated Surface

    Directory of Open Access Journals (Sweden)

    Huazhong Ren

    2015-03-01

    Full Text Available Multi-angular observation of land surface thermal radiation is considered to be a promising method of performing the angular normalization of land surface temperature (LST retrieved from remote sensing data. This paper focuses on an investigation of the minimum requirements of viewing angles to perform such normalizations on LST. The normally kernel-driven bi-directional reflectance distribution function (BRDF is first extended to the thermal infrared (TIR domain as TIR-BRDF model, and its uncertainty is shown to be less than 0.3 K when used to fit the hemispheric directional thermal radiation. A local optimum three-angle combination is found and verified using the TIR-BRDF model based on two patterns: the single-point pattern and the linear-array pattern. The TIR-BRDF is applied to an airborne multi-angular dataset to retrieve LST at nadir (Te-nadir from different viewing directions, and the results show that this model can obtain reliable Te-nadir from 3 to 4 directional observations with large angle intervals, thus corresponding to large temperature angular variations. The Te-nadir is generally larger than temperature of the slant direction, with a difference of approximately 0.5~2.0 K for vegetated pixels and up to several Kelvins for non-vegetated pixels. The findings of this paper will facilitate the future development of multi-angular thermal infrared sensors.

  2. Diode temperature sensor array for measuring and controlling micro scale surface temperature

    International Nuclear Information System (INIS)

    Han, Il Young; Kim, Sung Jin

    2004-01-01

    The needs of micro scale thermal detecting technique are increasing in biology and chemical industry. For example, thermal finger print, Micro PCR(Polymer Chain Reaction), TAS and so on. To satisfy these needs, we developed a DTSA(Diode Temperature Sensor Array) for detecting and controlling the temperature on small surface. The DTSA is fabricated by using VLSI technique. It consists of 32 array of diodes(1,024 diodes) for temperature detection and 8 heaters for temperature control on a 8mm surface area. The working principle of temperature detection is that the forward voltage drop across a silicon diode is approximately proportional to the inverse of the absolute temperature of diode. And eight heaters (1K) made of poly-silicon are added onto a silicon wafer and controlled individually to maintain a uniform temperature distribution across the DTSA. Flip chip packaging used for easy connection of the DTSA. The circuitry for scanning and controlling DTSA are also developed

  3. Disaggregation of SMOS soil moisture over West Africa using the Temperature and Vegetation Dryness Index based on SEVIRI land surface parameters

    DEFF Research Database (Denmark)

    Tagesson, T.; Horion, S.; Nieto, H.

    2018-01-01

    the Temperature and Vegetation Dryness Index (TVDI) that served as SM proxy within the disaggregation process. West Africa (3 N, 26 W; 28 N, 26 E) was selected as a case study as it presents both an important North-South climate gradient and a diverse range of ecosystem types. The main challenge was to set up...... resolution of SMOS SM, with potential application for local drought/flood monitoring of importance for the livelihood of the population of West Africa....

  4. Validation of AIRS V6 Surface Temperature over Greenland with GCN and NOAA Stations

    Science.gov (United States)

    Lee, Jae N.; Hearty, Thomas; Cullather, Richard; Nowicki, Sophie; Susskind, Joel

    2016-01-01

    This work compares the temporal and spatial characteristics of the AIRSAMSU (Atmospheric Infrared Sounder Advanced Microwave Sounding Unit A) Version 6 and MODIS (Moderate resolution Imaging Spectroradiometer) Collection 5 derived surface temperatures over Greenland. To estimate uncertainties in space-based surface temperature measurements, we re-projected the MODIS Ice Surface Temperature (IST) to 0.5 by 0.5 degree spatial resolution. We also re-gridded AIRS Skin Temperature (Ts) into the same grid but classified with different cloud conditions and surface types. These co-located data sets make intercomparison between the two instruments relatively straightforward. Using this approach, the spatial comparison between the monthly mean AIRS Ts and MODIS IST is in good agreement with RMS 2K for May 2012. This approach also allows the detection of any long-term calibration drift and the careful examination of calibration consistency in the MODIS and AIRS temperature data record. The temporal correlations between temperature data are also compared with those from in-situ measurements from GC-Net (GCN) and NOAA stations. The coherent time series of surface temperature evident in the correlation between AIRS Ts and GCN temperatures suggest that at monthly time scales both observations capture the same climate signal over Greenland. It is also suggested that AIRS surface air temperature (Ta) can be used to estimate the boundary layer inversion.

  5. A physically based analytical spatial air temperature and humidity model

    Science.gov (United States)

    Yang Yang; Theodore A. Endreny; David J. Nowak

    2013-01-01

    Spatial variation of urban surface air temperature and humidity influences human thermal comfort, the settling rate of atmospheric pollutants, and plant physiology and growth. Given the lack of observations, we developed a Physically based Analytical Spatial Air Temperature and Humidity (PASATH) model. The PASATH model calculates spatial solar radiation and heat...

  6. An experimental method for making spectral emittance and surface temperature measurements of opaque surfaces

    International Nuclear Information System (INIS)

    Moore, Travis J.; Jones, Matthew R.; Tree, Dale R.; Daniel Maynes, R.; Baxter, Larry L.

    2011-01-01

    An experimental procedure has been developed to make spectral emittance and temperature measurements. The spectral emittance of an object is calculated using measurements of the spectral emissive power and of the surface temperature of the object obtained using a Fourier transform infrared (FTIR) spectrometer. A calibration procedure is described in detail which accounts for the temperature dependence of the detector. The methods used to extract the spectral emissive power and surface temperature from measured infrared spectra were validated using a blackbody radiator at known temperatures. The average error in the measured spectral emittance was 2.1% and the average difference between the temperature inferred from the recorded spectra and the temperature indicated on the blackbody radiator was 1.2%. The method was used to measure the spectral emittance of oxidized copper at various temperatures.

  7. Assessment of broiler surface temperature variation when exposed to different air temperatures

    Directory of Open Access Journals (Sweden)

    GR Nascimento

    2011-12-01

    Full Text Available This study was conducted to determine the effect of the air temperature variation on the mean surface temperature (MST of 7- to 35-day-old broiler chickens using infrared thermometry to estimate MST, and to study surface temperature variation of the wings, head, legs, back and comb as affected by air temperature and broiler age. One hundred Cobb® broilers were used in the experiment. Starting on day 7, 10 birds were weekly selected at random, housed in an environmental chamber and reared under three distinct temperatures (18, 25 and 32 ºC to record their thermal profile using an infrared thermal camera. The recorded images were processed to estimate MST by selecting the whole area of the bird within the picture and comparing it with the values obtained using selected equations in literature, and to record the surface temperatures of the body parts. The MST estimated by infrared images were not statistically different (p > 0.05 from the values obtained by the equations. MST values significantly increased (p < 0.05 when the air temperature increased, but were not affected by bird age. However, age influenced the difference between MST and air temperature, which was highest on day 14. The technique of infrared thermal image analysis was useful to estimate the mean surface temperature of broiler chickens.

  8. Sea Surface Temperature Products and Research Associated with GHRSST

    Science.gov (United States)

    Kaiser-Weiss, Andrea K.; Minnett, Peter J.; Kaplan, Alexey; Wick, Gary A.; Castro, Sandra; Llewellyn-Jones, David; Merchant, Chris; LeBorgne, Pierre; Beggs, Helen; Donlon, Craig J.

    2012-03-01

    GHRSST serves its user community through the specification of operational Sea Surface Temperature (SST) products (Level 2, Level 3 and Level 4) based on international consensus. Providers of SST data from individual satellites create and deliver GHRSST-compliant near-real time products to a global GHRSST data assembly centre and a long-term stewardship facility. The GHRSST-compliant data include error estimates and supporting data for interpretation. Groups organised within GHRSST perform research on issues relevant to applying SST for air-sea exchange, for instance the Diurnal Variability Working Group (DVWG) analyses the evolution of the skin temperature. Other GHRSST groups concentrate on improving the SST estimate (Estimation and Retrievals Working Group EARWiG) and on improving the error characterization, (Satellite SST Validation Group, ST-VAL) and on improving the methods for SST analysis (Inter-Comparison Technical Advisory Group, IC-TAG). In this presentation we cover the data products and the scientific activities associated with GHRSST which might be relevant for investigating ocean-atmosphere interactions.

  9. Improving the performance of temperature index snowmelt model of SWAT by using MODIS land surface temperature data.

    Science.gov (United States)

    Yang, Yan; Onishi, Takeo; Hiramatsu, Ken

    2014-01-01

    Simulation results of the widely used temperature index snowmelt model are greatly influenced by input air temperature data. Spatially sparse air temperature data remain the main factor inducing uncertainties and errors in that model, which limits its applications. Thus, to solve this problem, we created new air temperature data using linear regression relationships that can be formulated based on MODIS land surface temperature data. The Soil Water Assessment Tool model, which includes an improved temperature index snowmelt module, was chosen to test the newly created data. By evaluating simulation performance for daily snowmelt in three test basins of the Amur River, performance of the newly created data was assessed. The coefficient of determination (R (2)) and Nash-Sutcliffe efficiency (NSE) were used for evaluation. The results indicate that MODIS land surface temperature data can be used as a new source for air temperature data creation. This will improve snow simulation using the temperature index model in an area with sparse air temperature observations.

  10. Regional evapotranspiration from an image-based implementation of the Surface Temperature Initiated Closure (STIC1.2) model and its validation across an aridity gradient in the conterminous US

    Science.gov (United States)

    Bhattarai, Nishan; Mallick, Kaniska; Brunsell, Nathaniel A.; Sun, Ge; Jain, Meha

    2018-04-01

    Recent studies have highlighted the need for improved characterizations of aerodynamic conductance and temperature (gA and T0) in thermal remote-sensing-based surface energy balance (SEB) models to reduce uncertainties in regional-scale evapotranspiration (ET) mapping. By integrating radiometric surface temperature (TR) into the Penman-Monteith (PM) equation and finding analytical solutions of gA and T0, this need was recently addressed by the Surface Temperature Initiated Closure (STIC) model. However, previous implementations of STIC were confined to the ecosystem-scale using flux tower observations of infrared temperature. This study demonstrates the first regional-scale implementation of the most recent version of the STIC model (STIC1.2) that integrates the Moderate Resolution Imaging Spectroradiometer (MODIS) derived TR and ancillary land surface variables in conjunction with NLDAS (North American Land Data Assimilation System) atmospheric variables into a combined structure of the PM and Shuttleworth-Wallace (SW) framework for estimating ET at 1 km × 1 km spatial resolution. Evaluation of STIC1.2 at 13 core AmeriFlux sites covering a broad spectrum of climates and biomes across an aridity gradient in the conterminous US suggests that STIC1.2 can provide spatially explicit ET maps with reliable accuracies from dry to wet extremes. When observed ET from one wet, one dry, and one normal precipitation year from all sites were combined, STIC1.2 explained 66 % of the variability in observed 8-day cumulative ET with a root mean square error (RMSE) of 7.4 mm/8-day, mean absolute error (MAE) of 5 mm/8-day, and percent bias (PBIAS) of -4 %. These error statistics showed relatively better accuracies than a widely used but previous version of the SEB-based Surface Energy Balance System (SEBS) model, which utilized a simple NDVI-based parameterization of surface roughness (zOM), and the PM-based MOD16 ET. SEBS was found to overestimate (PBIAS = 28 %) and MOD16 was found

  11. Heat waves measured with MODIS land surface temperature data predict changes in avian community structure

    Science.gov (United States)

    Thomas P. Albright; Anna M. Pidgeon; Chadwick D. Rittenhouse; Murray K. Clayton; Curtis H. Flather; Patrick D. Culbert; Volker C. Radeloff

    2011-01-01

    Heat waves are expected to become more frequent and severe as climate changes, with unknown consequences for biodiversity. We sought to identify ecologically-relevant broad-scale indicators of heat waves based on MODIS land surface temperature (LST) and interpolated air temperature data and assess their associations with avian community structure. Specifically, we...

  12. Sea surface temperature trends in the coastal ocean

    OpenAIRE

    Amos, C.L.; Al-Rashidi, Thamer B.; Rakha, Karim; El-Gamily, Hamdy; Nicholls, R.J.

    2013-01-01

    Sea surface temperature (SST) trends in the coastal zone are shown to be increasing at rates that exceed the global trends by up to an order of magnitude. This paper compiles some of the evidence of the trends published in the literature. The evidence suggests that urbanization in the coastal hinterland is having a direct effect on SST through increased temperatures of river and lake waters, as well as through heated run-off and thermal effluent discharges from coastal infrastructure. These l...

  13. Diurnal Variations of Titan's Surface Temperatures From Cassini -CIRS Observations

    Science.gov (United States)

    Cottini, Valeria; Nixon, Conor; Jennings, Don; Anderson, Carrie; Samuelson, Robert; Irwin, Patrick; Flasar, F. Michael

    The Cassini Composite Infrared Spectrometer (CIRS) observations of Saturn's largest moon, Titan, are providing us with the ability to detect the surface temperature of the planet by studying its outgoing radiance through a spectral window in the thermal infrared at 19 m (530 cm-1) characterized by low opacity. Since the first acquisitions of CIRS Titan data the in-strument has gathered a large amount of spectra covering a wide range of latitudes, longitudes and local times. We retrieve the surface temperature and the atmospheric temperature pro-file by modeling proper zonally averaged spectra of nadir observations with radiative transfer computations. Our forward model uses the correlated-k approximation for spectral opacity to calculate the emitted radiance, including contributions from collision induced pairs of CH4, N2 and H2, haze, and gaseous emission lines (Irwin et al. 2008). The retrieval method uses a non-linear least-squares optimal estimation technique to iteratively adjust the model parameters to achieve a spectral fit (Rodgers 2000). We show an accurate selection of the wide amount of data available in terms of footprint diameter on the planet and observational conditions, together with the retrieved results. Our results represent formal retrievals of surface brightness temperatures from the Cassini CIRS dataset using a full radiative transfer treatment, and we compare to the earlier findings of Jennings et al. (2009). The application of our methodology over wide areas has increased the planet coverage and accuracy of our knowledge of Titan's surface brightness temperature. In particular we had the chance to look for diurnal variations in surface temperature around the equator: a trend with slowly increasing temperature toward the late afternoon reveals that diurnal temperature changes are present on Titan surface. References: Irwin, P.G.J., et al.: "The NEMESIS planetary atmosphere radiative transfer and retrieval tool" (2008). JQSRT, Vol. 109, pp

  14. Effects of high temperature surface oxides on room temperature aqueous corrosion and environmental embrittlement of iron aluminides

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, R.A.; Perrin, R.L.

    1996-09-01

    Studies were conducted to determine the effects of high-temperature surface oxides, produced during thermomechanical processing, heat treatment (750 {degrees}C in air, one hour) or simulated in-service-type oxidation (1000{degrees}C in air, 24 hours) on the room-temperature aqueous-corrosion and environmental-embrittlement characteristics of iron aluminides. Materials evaluated included the Fe{sub 3}Al-based iron aluminides, FA-84, FA-129, FAL and FAL-Mo, a FeAl-based iron aluminide, FA-385, and a disordered low-aluminum Fe-Al alloy, FAPY. Tests were performed in a mild acid-chloride solution to simulate aggressive atmospheric corrosion. Cyclic-anodic-polarization tests were employed to evaluate resistances to localized aqueous corrosion. The high-temperature oxide surfaces consistently produced detrimental results relative to mechanically or chemically cleaned surfaces. Specifically, the pitting corrosion resistances were much lower for the as-processed and 750{degrees} C surfaces, relative to the cleaned surfaces, for FA-84, FA-129, FAL-Mo, FA-385 and FAPY. Furthermore, the pitting corrosion resistances were much lower for the 1000{degrees}C surfaces, relative to cleaned surfaces, for FA-129, FAL and FAL-Mo.

  15. Titan's Surface Temperatures Maps from Cassini - CIRS Observations

    Science.gov (United States)

    Cottini, Valeria; Nixon, C. A.; Jennings, D. E.; Anderson, C. M.; Samuelson, R. E.; Irwin, P. G. J.; Flasar, F. M.

    2009-09-01

    The Cassini Composite Infrared Spectrometer (CIRS) observations of Saturn's largest moon, Titan, are providing us with the ability to detect the surface temperature of the planet by studying its outgoing radiance through a spectral window in the thermal infrared at 19 μm (530 cm-1) characterized by low opacity. Since the first acquisitions of CIRS Titan data the instrument has gathered a large amount of spectra covering a wide range of latitudes, longitudes and local times. We retrieve the surface temperature and the atmospheric temperature profile by modeling proper zonally averaged spectra of nadir observations with radiative transfer computations. Our forward model uses the correlated-k approximation for spectral opacity to calculate the emitted radiance, including contributions from collision induced pairs of CH4, N2 and H2, haze, and gaseous emission lines (Irwin et al. 2008). The retrieval method uses a non-linear least-squares optimal estimation technique to iteratively adjust the model parameters to achieve a spectral fit (Rodgers 2000). We show an accurate selection of the wide amount of data available in terms of footprint diameter on the planet and observational conditions, together with the retrieved results. Our results represent formal retrievals of surface brightness temperatures from the Cassini CIRS dataset using a full radiative transfer treatment, and we compare to the earlier findings of Jennings et al. (2009). In future, application of our methodology over wide areas should greatly increase the planet coverage and accuracy of our knowledge of Titan's surface brightness temperature. References: Irwin, P.G.J., et al.: "The NEMESIS planetary atmosphere radiative transfer and retrieval tool" (2008). JQSRT, Vol. 109, pp. 1136-1150, 2008. Rodgers, C. D.: "Inverse Methods For Atmospheric Sounding: Theory and Practice". World Scientific, Singapore, 2000. Jennings, D.E., et al.: "Titan's Surface Brightness Temperatures." Ap. J. L., Vol. 691, pp. L103-L

  16. The Remote Sensing of Surface Radiative Temperature over Barbados.

    Science.gov (United States)

    remote sensing of surface radiative temperature over Barbados was undertaken using a PRT-5 attached to a light aircraft. Traverses across the centre of the island, over the rugged east coast area, and the urban area of Bridgetown were undertaken at different times of day and night in the last week of June and the first week of December, 1969. These traverses show that surface variations in long-wave radiation emission lie within plus or minus 5% of the observations over grass at a representative site. The quick response of the surface to sunset and sunrise was

  17. Maximum surface level and temperature histories for Hanford waste tanks

    International Nuclear Information System (INIS)

    Flanagan, B.D.; Ha, N.D.; Huisingh, J.S.

    1994-01-01

    Radioactive defense waste resulting from the chemical processing of spent nuclear fuel has been accumulating at the Hanford Site since 1944. This waste is stored in underground waste-storage tanks. The Hanford Site Tank Farm Facilities Interim Safety Basis (ISB) provides a ready reference to the safety envelope for applicable tank farm facilities and installations. During preparation of the ISB, tank structural integrity concerns were identified as a key element in defining the safety envelope. These concerns, along with several deficiencies in the technical bases associated with the structural integrity issues and the corresponding operational limits/controls specified for conduct of normal tank farm operations are documented in the ISB. Consequently, a plan was initiated to upgrade the safety envelope technical bases by conducting Accelerated Safety Analyses-Phase 1 (ASA-Phase 1) sensitivity studies and additional structural evaluations. The purpose of this report is to facilitate the ASA-Phase 1 studies and future analyses of the single-shell tanks (SSTs) and double-shell tanks (DSTs) by compiling a quantitative summary of some of the past operating conditions the tanks have experienced during their existence. This report documents the available summaries of recorded maximum surface levels and maximum waste temperatures and references other sources for more specific data

  18. An Estimation of Land Surface Temperatures from Landsat ETM+ ...

    African Journals Online (AJOL)

    Dr-Adeline

    Keywords: Urban growth, urban heat Island, land surface temperatures, ... climate from the resulting increase in LST can impact on the development of ... were not available (due to high cloud cover) in a given season, 2011 images ..... Sailor, D.J. and H. Fan, 2002: Modeling the diurnal variability of effective albedo for cities.

  19. Solitary ionizing surface waves on low-temperature plasmas

    International Nuclear Information System (INIS)

    Vladimirov, S.V.; Yu, M.Y.

    1993-01-01

    It is demonstrated that at the boundary of semi-infinite low-temperature plasma new types of localized ionizing surface wave structures can propagate. The solitary waves are described by an evolution equation similar to the KdV equation, but the solutions differ considerably from that of the latter

  20. Sea surface temperature anomalies in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    RameshKumar, M.R.

    temperature anomalies for the above regions respectively. An analysis has shown that most of the short duration anomalies (i.e., anomalies with periods less than 4 months) are driven by the surface heat fluxes. The medium duration anomalies (i.e., anomalies...

  1. Surface and temperature effects in isovector giant resonances

    International Nuclear Information System (INIS)

    Lipparini, E.; Stringari, S.

    1988-01-01

    Using the liquid droplet model (LDM) we investigate three different sum rules for the isovector dipole and monopole excitations. Analytical formulae are derived for the excitation energies of these resonances and the predictions are compared with experiments. The role of the surface and the effects of temperature are explicitly discussed. (orig.)

  2. Surface Intermediates on Metal Electrodes at High Temperature

    DEFF Research Database (Denmark)

    Zachau-Christiansen, Birgit; Jacobsen, Torben; Bay, Lasse

    1997-01-01

    The mechanisms widely suggested for the O2-reduc-tion or H2-oxidation SOFC reactions involve inter-mediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In airat moderate temperatures (500øC) Pt in contact with YSZ...

  3. Heterogeneity of soil surface temperature induced by xerophytic ...

    Indian Academy of Sciences (India)

    The diurnal maximum and diurnal variations of soil surface temperatures under canopy vary strongly with different .... elevation of 1300 m above sea level), located at the southeastern fringe of ... cipitation is the only source of soil water replenish- ment. ...... 2001 Effects of nutrients and shade on tree-grass inter- actions in an ...

  4. Surface intermediates on metal electrodes at high temperatures

    DEFF Research Database (Denmark)

    Zachau-Christiansen, Birgit; Jacobsen, Torben; Bay, Lasse

    1998-01-01

    The mechanisms widely conceived for the O(2)-reduction or H(2)-oxidation reactions in SOFC's involve intermediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In air at moderate temperatures (500 degrees C) Pt...

  5. Temperature limit values for touching cold surfaces with the fingertip

    NARCIS (Netherlands)

    Geng, Q.; Holme, I.; Hartog, E.A. den; Havenith, G.; Jay, O.; Malchaires, J.; Piette, A.; Rintama, H.; Rissanen, S.

    2006-01-01

    Objectives: At the request of the European Commission and in the framework of the European Machinery Directive, research was performed in five different laboratories to develop specifications for surface temperature limit values for the short-term accidental touching of the fingertip with cold

  6. Near-surface temperature gradient in a coastal upwelling regime

    Science.gov (United States)

    Maske, H.; Ochoa, J.; Almeda-Jauregui, C. O.; Ruiz-de la Torre, M. C.; Cruz-López, R.; Villegas-Mendoza, J. R.

    2014-08-01

    In oceanography, a near homogeneous mixed layer extending from the surface to a seasonal thermocline is a common conceptual basis in physics, chemistry, and biology. In a coastal upwelling region 3 km off the coast in the Mexican Pacific, we measured vertical density gradients with a free-rising CTD and temperature gradients with thermographs at 1, 3, and 5 m depths logging every 5 min during more than a year. No significant salinity gradient was observed down to 10 m depth, and the CTD temperature and density gradients showed no pronounced discontinuity that would suggest a near-surface mixed layer. Thermographs generally logged decreasing temperature with depth with gradients higher than 0.2 K m-1 more than half of the time in the summer between 1 and 3 m, 3 and 5 m and in the winter between 1 and 3 m. Some negative temperature gradients were present and gradients were generally highly variable in time with high peaks lasting fractions of hours to hours. These temporal changes were too rapid to be explained by local heating or cooling. The pattern of positive and negative peaks might be explained by vertical stacks of water layers of different temperatures and different horizontal drift vectors. The observed near-surface gradient has implications for turbulent wind energy transfer, vertical exchange of dissolved and particulate water constituents, the interpretation of remotely sensed SST, and horizontal wind-induced transport.

  7. Temperature of the Icelandic crust: Inferred from electrical conductivity, temperature surface gradient, and maximum depth of earthquakes

    Science.gov (United States)

    Björnsson, Axel

    2008-02-01

    Two different models of the structure of the Icelandic crust have been presented. One is the thin-crust model with a 10-15 km thick crust beneath the axial rift zones, with an intermediate layer of partially molten basalt at the base of the crust and on the top of an up-domed asthenosphere. The thick-crust model assumes a 40 km thick and relatively cold crust beneath central Iceland. The most important and crucial parameter to distinguish between these different models is the temperature distribution with depth. Three methods are used to estimate the temperature distribution with depth. First, the surface temperature gradient measured in shallow wells drilled outside geothermal areas. Second, the thickness of the seismogenic zone which is associated with a 750 °C isothermal surface. Third, the depth to a layer with high electrical conductivity which is associated with partially molten basalt with temperature around 1100 °C at the base of the crust. Combination of these data shows that the temperature gradient can be assumed to be nearly linear from the surface down to the base of the crust. These results are strongly in favour of the thin-crust model. The scattered deep seismic reflectors interpreted as Moho in the thick-crust model could be caused by phase transitions or reflections from melt pockets in the mantle.

  8. Effects of temperature and surface orientation on migration behaviours of helium atoms near tungsten surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoshuang; Wu, Zhangwen; Hou, Qing, E-mail: qhou@scu.edu.cn

    2015-10-15

    Molecular dynamics simulations were performed to study the dependence of migration behaviours of single helium atoms near tungsten surfaces on the surface orientation and temperature. For W{100} and W{110} surfaces, He atoms can quickly escape out near the surface without accumulation even at a temperature of 400 K. The behaviours of helium atoms can be well-described by the theory of continuous diffusion of particles in a semi-infinite medium. For a W{111} surface, the situation is complex. Different types of trap mutations occur within the neighbouring region of the W{111} surface. The trap mutations hinder the escape of He atoms, resulting in their accumulation. The probability of a He atom escaping into vacuum from a trap mutation depends on the type of the trap mutation, and the occurrence probabilities of the different types of trap mutations are dependent on the temperature. This finding suggests that the escape rate of He atoms on the W{111} surface does not show a monotonic dependence on temperature. For instance, the escape rate at T = 1500 K is lower than the rate at T = 1100 K. Our results are useful for understanding the structural evolution and He release on tungsten surfaces and for designing models in other simulation methods beyond molecular dynamics.

  9. Numerically predicting horizontally oriented spent fuel rod surface temperatures

    International Nuclear Information System (INIS)

    Wix, S.D.; Koski, J.A.

    1993-01-01

    A comparison between numerical calculations with use of commercial thermal analysis software packages and experimental data simulating a horizontally oriented spent fuel rod array was performed. Twelve cases were analyzed using air and helium for the fill gas, with three different heat dissipation levels. The numerically predicted temperatures are higher than the experimental data for all levels of heat dissipation with air as the fill gas. The temperature differences are 4 degrees C and 23 degrees C for the low heat dissipation and high dissipation, respectively. The temperature predictions using helium as a fill gas are lower than the experimental data for the low and medium heat dissipation levels. The temperature predictions are 1 degrees C and 6 degrees C lower than the experimental data for the low and medium heat dissipation, respectively. For the high heat dissipation level, the temperature predictions are 16 degrees C higher than the experimental data. Differences between the predicted and experimental temperatures can be attributed to several factors. These factors include a experimental uncertainity in the temperature and heat dissipation measurements, actual convection effects not included in the model, and axial heat flow in the experimental data. This works demonstrates that horizontally oriented spent fuel rod surface temperature predictions can be made using existing commercial software packages. This work also shows that end effects, such as axial heat transfer through the spent fuel rods, will be increasingly important as the amount of dissipated heat increases

  10. Numerically predicting horizontally oriented spent fuel rod surface temperatures

    International Nuclear Information System (INIS)

    Wix, S.D.; Koski, J.A.

    1992-01-01

    A comparison between numerical calculations with use of commercial thermal analysis software packages and experimental data simulating a horizontally oriented spent fuel rod array was performed. Twelve cases were analyzed using air and helium for the fill gas, with three different heat dissipation levels. The numerically predicted temperatures are higher than the experimental data for all levels of heat dissipation with air as the fill gas. The temperature differences are 4 degree C and 23 degree C for the low heat dissipation and high heat dissipation, respectively. The temperature predictions using helium as a fill gas are lower than the experimental data for the low and medium heat dissipation levels. The temperature predictions are 1 degree C and 6 degree C lower than the experimental data for the low and medium heat dissipation, respectively. For the high heat dissipation level, the temperature predictions are 16 degree C higher than the experimental data. Differences between the predicted and experimental temperatures can be attributed to several factors. These factors include experimental uncertainty in the temperature and heat dissipation measurements, actual convection effects not included in the model, and axial heat flow in the experimental data. This work demonstrates that horizontally oriented spent fuel rod surface temperature predictions can be made using existing commercial software packages. This work also shows that end effects, such as axial heat transfer through the spent fuel rods, will be increasingly important as the amount of dissipated heat increases

  11. Comparison of Four Models of Radiative Heat Transfer Between Flat Surface to Evaluate the Temperature Field Based on Example of the Continuous Casting Mould

    Directory of Open Access Journals (Sweden)

    Rywotycki M.

    2015-04-01

    Full Text Available The paper presents the results of research concerning the influence of radiative heat transfer on the strand and mould interface. The four models for determining the heat transfer boundary conditions within the primary cooling zone for the continuous casting process of steel have been presented. A cast slab - with dimensions of 1280×220 mm - has been analysed. Models describing the heat transfer by radiation have been specified and applied in the numerical calculations. The problem has been solved by applying the finite element method and the self-developed software. The simulation results, along with their analysis, have been presented. The developed models have been verified based on the data obtained from the measurements at the industrial facility.

  12. Quantifying Surface Energy Flux Estimation Uncertainty Using Land Surface Temperature Observations

    Science.gov (United States)

    French, A. N.; Hunsaker, D.; Thorp, K.; Bronson, K. F.

    2015-12-01

    Remote sensing with thermal infrared is widely recognized as good way to estimate surface heat fluxes, map crop water use, and detect water-stressed vegetation. When combined with net radiation and soil heat flux data, observations of sensible heat fluxes derived from surface temperatures (LST) are indicative of instantaneous evapotranspiration (ET). There are, however, substantial reasons LST data may not provide the best way to estimate of ET. For example, it is well known that observations and models of LST, air temperature, or estimates of transport resistances may be so inaccurate that physically based model nevertheless yield non-meaningful results. Furthermore, using visible and near infrared remote sensing observations collected at the same time as LST often yield physically plausible results because they are constrained by less dynamic surface conditions such as green fractional cover. Although sensitivity studies exist that help identify likely sources of error and uncertainty, ET studies typically do not provide a way to assess the relative importance of modeling ET with and without LST inputs. To better quantify model benefits and degradations due to LST observational inaccuracies, a Bayesian uncertainty study was undertaken using data collected in remote sensing experiments at Maricopa, Arizona. Visible, near infrared and thermal infrared data were obtained from an airborne platform. The prior probability distribution of ET estimates were modeled using fractional cover, local weather data and a Penman-Monteith mode, while the likelihood of LST data was modeled from a two-source energy balance model. Thus the posterior probabilities of ET represented the value added by using LST data. Results from an ET study over cotton grown in 2014 and 2015 showed significantly reduced ET confidence intervals when LST data were incorporated.

  13. ENHANCED MODELING OF REMOTELY SENSED ANNUAL LAND SURFACE TEMPERATURE CYCLE

    Directory of Open Access Journals (Sweden)

    Z. Zou

    2017-09-01

    Full Text Available Satellite thermal remote sensing provides access to acquire large-scale Land surface temperature (LST data, but also generates missing and abnormal values resulting from non-clear-sky conditions. Given this limitation, Annual Temperature Cycle (ATC model was employed to reconstruct the continuous daily LST data over a year. The original model ATCO used harmonic functions, but the dramatic changes of the real LST caused by the weather changes remained unclear due to the smooth sine curve. Using Aqua/MODIS LST products, NDVI and meteorological data, we proposed enhanced model ATCE based on ATCO to describe the fluctuation and compared their performances for the Yangtze River Delta region of China. The results demonstrated that, the overall root mean square errors (RMSEs of the ATCE was lower than ATCO, and the improved accuracy of daytime was better than that of night, with the errors decreased by 0.64 K and 0.36 K, respectively. The improvements of accuracies varied with different land cover types: the forest, grassland and built-up areas improved larger than water. And the spatial heterogeneity was observed for performance of ATC model: the RMSEs of built-up area, forest and grassland were around 3.0 K in the daytime, while the water attained 2.27 K; at night, the accuracies of all types significantly increased to similar RMSEs level about 2 K. By comparing the differences between LSTs simulated by two models in different seasons, it was found that the differences were smaller in the spring and autumn, while larger in the summer and winter.

  14. Unexpected and Unexplained Surface Temperature Variations on Mimas

    Science.gov (United States)

    Howett, C.; Spencer, J. R.; Pearl, J. C.; Hurford, T. A.; Segura, M.; Cassini Cirs Team

    2010-12-01

    Until recently it was thought one of the most interesting things about Mimas, Saturn’s innermost classical icy moon, was its resemblance to Star Wars’ Death Star. However, a bizarre pattern of daytime surface temperatures was observed on Mimas using data obtained by Cassini’s Composite Infrared Spectrometer (CIRS) in February 2010. The observations were taken during Cassini’s closest ever encounter with Mimas (<10,000 km) and cover the daytime anti-Saturn hemisphere centered on longitude ~145° W. Instead of surface temperatures smoothly increasing throughout the morning and early afternoon, then cooling in the evening, as expected, a sharp V-shaped boundary is observed separating cooler midday and afternoon temperatures (~77 K) on the leading side from warmer morning temperatures (~92 K) on the trailing side. The boundary’s apex is centered at equatorial latitudes near the anti-Saturn point and extends to low north and south latitudes on the trailing side. Subtle differences in the surface colors have been observed that are roughly spatially correlated with the observed extent of the temperature anomaly, with the cooler regions tending to be bluer (Schenk et al., Submitted). However, visible-wavelength albedo is similar in the two regions, so albedo variations are probably not directly responsible for the thermal anomaly. It is more likely that thermal inertia variations produce the anomaly, with thermal inertia being unusually high in the region with anomalously low daytime temperatures. Comparison of the February 2010 CIRS data to previous lower spatial resolution data taken at different local times tentatively confirm that the cooler regions do indeed display higher thermal inertias. Bombardment of the surface by high energy electrons from Saturn’s radiation belts has been proposed to explain the observed color variations (Schenk et al., Submitted). Electrons above ~1 MeV preferentially impact Mimas’ leading hemisphere at low latitudes where they

  15. Improving Land Surface Temperature Retrievals over Mountainous Regions

    Directory of Open Access Journals (Sweden)

    Virgílio A. Bento

    2017-01-01

    Full Text Available Algorithms for Land Surface Temperature (LST retrieval from infrared measurements are usually sensitive to the amount of water vapor present in the atmosphere. The Satellite Application Facilities on Climate Monitoring and Land Surface Analysis (CM SAF and LSA SAF are currently compiling a 25 year LST Climate data record (CDR, which uses water vapor information from ERA-Int reanalysis. However, its relatively coarse spatial resolution may lead to systematic errors in the humidity profiles with implications in LST, particularly over mountainous areas. The present study compares LST estimated with three different retrieval algorithms: a radiative transfer-based physical mono-window (PMW, a statistical mono-window (SMW, and a generalized split-windows (GSW. The algorithms were tested over the Alpine region using ERA-Int reanalysis data and relied on the finer spatial scale Consortium for Small-Scale Modelling (COSMO model data as a reference. Two methods were developed to correct ERA-Int water vapor misestimation: (1 an exponential parametrization of total precipitable water (TPW appropriate for SMW/GSW; and (2 a level reduction method to be used in PMW. When ERA-Int TPW was used, the algorithm missed the right TPW class in 87% of the cases. When the exponential parametrization was used, the missing class rate decreased to 9%, and when the level reduction method was applied, the LST corrections went up to 1.7 K over the study region. Overall, the correction for pixel orography in TPW leads to corrections in LST estimations, which are relevant to ensure that long-term LST records meet climate requirements, particularly over mountainous regions.

  16. Ocean Surface Current Vectors from MODIS Terra/Aqua Sea Surface Temperature Image Pairs, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellites that record imagery of the same sea surface area, at times separated by a few hours, can be used to estimate ocean surface velocity fields based on the...

  17. Impervious surfaces and sewer pipe effects on stormwater runoff temperature

    Science.gov (United States)

    Sabouri, F.; Gharabaghi, B.; Mahboubi, A. A.; McBean, E. A.

    2013-10-01

    The warming effect of the impervious surfaces in urban catchment areas and the cooling effect of underground storm sewer pipes on stormwater runoff temperature are assessed. Four urban residential catchment areas in the Cities of Guelph and Kitchener, Ontario, Canada were evaluated using a combination of runoff monitoring and modelling. The stormwater level and water temperature were monitored at 10 min interval at the inlet of the stormwater management ponds for three summers 2009, 2010 and 2011. The warming effect of the ponds is also studied, however discussed in detail in a separate paper. An artificial neural network (ANN) model for stormwater temperature was trained and validated using monitoring data. Stormwater runoff temperature was most sensitive to event mean temperature of the rainfall (EMTR) with a normalized sensitivity coefficient (Sn) of 1.257. Subsequent levels of sensitivity corresponded to the longest sewer pipe length (LPL), maximum rainfall intensity (MI), percent impervious cover (IMP), rainfall depth (R), initial asphalt temperature (AspT), pipe network density (PND), and rainfall duration (D), respectively. Percent impervious cover of the catchment area (IMP) was the key parameter that represented the warming effect of the paved surfaces; sensitivity analysis showed IMP increase from 20% to 50% resulted in runoff temperature increase by 3 °C. The longest storm sewer pipe length (LPL) and the storm sewer pipe network density (PND) are the two key parameters that control the cooling effect of the underground sewer system; sensitivity analysis showed LPL increase from 345 to 966 m, resulted in runoff temperature drop by 2.5 °C.

  18. Influence of the atomic structure of crystal surfaces on the surface diffusion in medium temperature range

    International Nuclear Information System (INIS)

    Cousty, J.P.

    1981-12-01

    In this work, we have studied the influence of atomic structure of crystal surface on surface self-diffusion in the medium temperature range. Two ways are followed. First, we have measured, using a radiotracer method, the self-diffusion coefficient at 820 K (0.6 T melting) on copper surfaces both the structure and the cleanliness of which were stable during the experiment. We have shown that the interaction between mobile surface defects and steps can be studied through measurements of the anisotropy of surface self diffusion. Second, the behavior of an adatom and a surface vacancy is simulated via a molecular dynamics method, on several surfaces of a Lennard Jones crystal. An inventory of possible migration mechanisms of these surface defects has been drawn between 0.35 and 0.45 Tsub(m). The results obtained with both the methods point out the influence of the surface atomic structure in surface self-diffusion in the medium temperature range [fr

  19. The impact of climatic and non-climatic factors on land surface temperature in southwestern Romania

    Science.gov (United States)

    Roşca, Cristina Florina; Harpa, Gabriela Victoria; Croitoru, Adina-Eliza; Herbel, Ioana; Imbroane, Alexandru Mircea; Burada, Doina Cristina

    2017-11-01

    Land surface temperature is one of the most important parameters related to global warming. It depends mainly on soil type, discontinuous vegetation cover, or lack of precipitation. The main purpose of this paper is to investigate the relationship between high LST, synoptic conditions and air masses trajectories, vegetation cover, and soil type in one of the driest region in Romania. In order to calculate the land surface temperature and normalized difference vegetation index, five satellite images of LANDSAT missions 5 and 7, covering a period of 26 years (1986-2011), were selected, all of them collected in the month of June. The areas with low vegetation density were derived from normalized difference vegetation index, while soil types have been extracted from Corine Land Cover database. HYSPLIT application was employed to identify the air masses origin based on their backward trajectories for each of the five study cases. Pearson, logarithmic, and quadratic correlations were used to detect the relationships between land surface temperature and observed ground temperatures, as well as between land surface temperature and normalized difference vegetation index. The most important findings are: strong correlation between land surface temperature derived from satellite images and maximum ground temperature recorded in a weather station located in the area, as well as between areas with land surface temperature equal to or higher than 40.0 °C and those with lack of vegetation; the sandy soils are the most prone to high land surface temperature and lack of vegetation, followed by the chernozems and brown soils; extremely severe drought events may occur in the region.

  20. High Precision Infrared Temperature Measurement System Based on Distance Compensation

    Directory of Open Access Journals (Sweden)

    Chen Jing

    2017-01-01

    Full Text Available To meet the need of real-time remote monitoring of human body surface temperature for optical rehabilitation therapy, a non-contact high-precision real-time temperature measurement method based on distance compensation was proposed, and the system design was carried out. The microcontroller controls the infrared temperature measurement module and the laser range module to collect temperature and distance data. The compensation formula of temperature with distance wass fitted according to the least square method. Testing had been performed on different individuals to verify the accuracy of the system. The results indicate that the designed non-contact infrared temperature measurement system has a residual error of less than 0.2°C and the response time isless than 0.1s in the range of 0 to 60cm. This provides a reference for developing long-distance temperature measurement equipment in optical rehabilitation therapy.

  1. Increase of body surface temperature and blood flow by theanine

    International Nuclear Information System (INIS)

    Hasegawa, Takeo; Noguchi, Kenichi; Ando, Satoshi

    2002-01-01

    Suntheanine (Taiyo Kagaku Co.: Theanine) is the trade name for L-theanine which is a unique amino acid found almost solely in tea plants, responsible for the exotictaste of green tea. We investigated the effects of relate to relaxation, improves the taste of processed foods, radiation sensitization, and increase of body surface temperature in vivo study. The results of the present study confirmed, (1) Suntheanine is incorporated into the brain and induces the emission of α -waves an induced of relaxation. (2) Body surface temperature and blood flow on skin were increased after administration of Suntheanine. (3) There was effects of radiation sensitization in whole body irradiation of X-rays after Suntheanine IP injection on C3H mice. (4) Acute toxicity, subacute toxicity and mutagen testconfirm the safety Suntheanine in this study

  2. GHRSST Level 2P Global Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite produced by NAVO (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  3. GHRSST Level 2P Global Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset based on multi-channel sea surface temperature (SST) retrievals from the...

  4. GHRSST Level 2P Global Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-16 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset based on multi-channel sea surface temperature (SST) retrievals from the...

  5. GHRSST Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite produced by NAVO (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  6. GHRSST Level 2P Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-18 satellite produced by NAVO (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  7. Estimation of precipitable water from surface dew point temperature

    International Nuclear Information System (INIS)

    Abdel Wahab, M.; Sharif, T.A.

    1991-09-01

    The Reitan (1963) regression equation which is of the form lnw=a+bT d has been examined and tested to estimate precipitable water content from surface dew point temperature at different locations. The study confirms that the slope of this equation (b) remains constant at the value of .0681 deg. C., while the intercept (a) changes rapidly with the latitude. The use of the variable intercept can improve the estimated result by 2%. (author). 6 refs, 4 figs, 3 tabs

  8. Patellar Skin Surface Temperature by Thermography Reflects Knee Osteoarthritis Severity

    OpenAIRE

    Anna E. Denoble; Norine Hall; Carl F. Pieper; Virginia B. Kraus

    2010-01-01

    Background: Digital infrared thermal imaging is a means of measuring the heat radiated from the skin surface. Our goal was to develop and assess the reproducibility of serial infrared measurements of the knee and to assess the association of knee temperature by region of interest with radiographic severity of knee Osteoarthritis (rOA). Methods: A total of 30 women (15 Cases with symptomatic knee OA and 15 age-matched Controls without knee pain or knee OA) participated in this study. Infrared ...

  9. Interannual variability of north Atlantic Sea surface temperatures

    International Nuclear Information System (INIS)

    Bhatt, U.S.; Battisiti, D.S.; Alexander, M.A.

    1994-01-01

    In the midlatitude north Atlantic Ocean the pattern of sea surface temperature anomalies (ssta) is characterized by a north-south dipole. Bjerknes was the first to propose that the banded structure was associated with the interannual variability. Recently, these patterns have been studied more extensively. In this study the quantitative aspects of these patterns are examined through the use of a mixed-layer model (MLM)

  10. Evaluation of thermocouple fin effect in cladding surface temperature measurement during film boiling

    International Nuclear Information System (INIS)

    Tsuruta, Takaharu; Fujishiro, Toshio

    1984-01-01

    Thermocouple fin effect on surface temperature measurement of a fuel rod has been studied at elevated wall temperatures under film boiling condition in a reactivity initiated accident (RIA) situation. This paper presents an analytical equation to evaluate temperature drops caused by the thermocouple wires attached to cladding surface. The equation yielded the local temperature drop at measuring point depending on thermocouple diameter, cladding temperature, coolant flow condition and vapor film thickness. The temperature drops by the evaluating equation were shown in cases of free and forced convection conditions. The analytical results were compared with the measured data for various thermocouple sizes, and also with the estimated maximum cladding temperature based on the oxidation layer thickness in the cladding outer surface. It was concluded that the temperature drops at above 1,000 0 C in cladding temperature were around 120 and 150 0 C for 0.2 and 0.3 mm diameter Pt-Pt.Rh thermocouples, respectively, under a stagnant coolant condition. The fin effect increases with the decrease of vapor film thickness such as under forced flow cooling or at near the quenching point. (author)

  11. An evaluation of the impact of aerosol particles on weather forecasts from a biomass burning aerosol event over the Midwestern United States: observational-based analysis of surface temperature

    Directory of Open Access Journals (Sweden)

    J. Zhang

    2016-05-01

    Full Text Available A major continental-scale biomass burning smoke event from 28–30 June 2015, spanning central Canada through the eastern seaboard of the United States, resulted in unforecasted drops in daytime high surface temperatures on the order of 2–5  °C in the upper Midwest. This event, with strong smoke gradients and largely cloud-free conditions, provides a natural laboratory to study how aerosol radiative effects may influence numerical weather prediction (NWP forecast outcomes. Here, we describe the nature of this smoke event and evaluate the differences in observed near-surface air temperatures between Bismarck (clear and Grand Forks (overcast smoke, to evaluate to what degree solar radiation forcing from a smoke plume introduces daytime surface cooling, and how this affects model bias in forecasts and analyses. For this event, mid-visible (550 nm smoke aerosol optical thickness (AOT, τ reached values above 5. A direct surface cooling efficiency of −1.5 °C per unit AOT (at 550 nm, τ550 was found. A further analysis of European Centre for Medium-Range Weather Forecasts (ECMWF, National Centers for Environmental Prediction (NCEP, United Kingdom Meteorological Office (UKMO near-surface air temperature forecasts for up to 54 h as a function of Moderate Resolution Imaging Spectroradiometer (MODIS Dark Target AOT data across more than 400 surface stations, also indicated the presence of the daytime aerosol direct cooling effect, but suggested a smaller aerosol direct surface cooling efficiency with magnitude on the order of −0.25 to −1.0 °C per unit τ550. In addition, using observations from the surface stations, uncertainties in near-surface air temperatures from ECMWF, NCEP, and UKMO model runs are estimated. This study further suggests that significant daily changes in τ550 above 1, at which the smoke-aerosol-induced direct surface cooling effect could be comparable in magnitude with model uncertainties, are rare events

  12. Intraseasonal sea surface temperature variability in Indonesian seas

    Science.gov (United States)

    Napitu, A. M.; Gordon, A. L.; Yuan, X.

    2012-12-01

    The satellite-derived sea surface temperature (SST) data, 1998-mid 2012, are used to examine intraseasonal variability (ISV; 20-90 days) across the Indonesian seas. The most energetic ISV is observed in the Banda Sea and across the Indo-Australia basin with an The satellite-derived sea surface temperature (SST) data, 1998-mid 2012, are used to examine intraseasonal variability (ISV; 20-90 days) across the Indonesian seas. The most energetic ISV is observed in the Banda Sea and across the Indo-Australia basin with an average SST standard deviation (STD) between 0.4-0.5°C, with strongest signature during boreal winter. What physical processes force the SST ISV variability within the Indonesian seas? Ocean process, sea-air interaction, or both? To help identify the main forcing, the satellite derived outgoing longwave radiation (OLR) and wind stress data in the region are examined. The OLR shows robust intraseasonal variations and is significantly correlated with the SST, particularly for variability with periods of 30-60 days, with OLR accounting for ~60-70% of the SST variance. The OLR is also maximum during boreal winter. Conversely, the surface wind may play insignificant role in perturbing the SST at intraseasonal timescales as shown by weak correlation between wind stress and SST. We thus suspect that the surface solar flux (suggested by the OLR) is likely more dominant than the surface turbulent heat flux (indicated by the surface wind) as the main source for the ISV in the SST in Indonesian seas. Furthermore the maximum OLR phase, coupled with a period of minimum mixed layer depth, may explain the strong SST variation during boreal winter in Indonesian seas. The influence of the Madden-Julian Oscillation (MJO) on the OLR and SST variability is currently being evaluated.

  13. Land surface skin temperature climatology: benefitting from the strengths of satellite observations

    International Nuclear Information System (INIS)

    Jin Menglin; Dickinson, Robert E

    2010-01-01

    Surface skin temperature observations (T skin ), as obtained by satellite remote sensing, provide useful climatological information of high spatial resolution and global coverage that enhances the traditional ground observations of surface air temperature (T air ) and so, reveal new information about land surface characteristics. This letter analyzes nine years of moderate-resolution imaging spectroradiometer (MODIS) skin temperature observations to present monthly skin temperature diurnal, seasonal, and inter-annual variations at a 0.05 deg. latitude/longitude grid over the global land surface and combines these measurements with other MODIS-based variables in an effort to understand the physical mechanisms responsible for T skin variations. In particular, skin temperature variations are found to be closely related to vegetation cover, clouds, and water vapor, but to differ from 2 m surface T air in terms of both physical meaning and magnitude. Therefore, the two temperatures (T skin and T air ) are complementary in their contribution of valuable information to the study of climate change.

  14. Sensitivity of LUCC on the Surface Temperature of Tibetan Plateau

    Science.gov (United States)

    Qi, W.; Deng, X.; Wu, F.

    2016-12-01

    The Tibetan Plateau has an important effect on the ecological security in China, even in Asia, which makes the region become the hot spot in recently research. Under the joint influence of global change and human activities, ecosystem destabilizing and the increasing pressure on resources and environment emerge on the Tibetan Plateau, but the potential spatial sensitivity of land use and land cover changes(LUCC) on surface temperature has not been quantitatively analyzed. This study analyzed the mainly types of LUCC, urbanization, grassland degradation, deforestation on Tibetan Plateau along with Representative Concentration Pathways (RCPs) of the Intergovernmental Panel on Climate Change (IPCC). The LUCC in recent decades was first quantitatively analyzed in this study to give the basic fact with a significant increase in temperatures, reduced precipitation and increased evaporation. This study focused on the future spatio-temporal heterogeneity of the temperature and precipitation. Finally, the influencing factors with LUCC on Tibetan Plateau were simulated with the Weather Research and Forecasting (WRF) model, and the sensitivity of different land use types was spatially analyzed with Singular Value Decomposition (SVD). The results indicate that the large-area alpine grassland plays a more important role in alleviating global warming than other vegetation types do. The changes of the landscape structure resulting from the urban expansion play a significant role in intensifying regional temperature increase. In addition, the effects of LUCC on monthly average temperature change would vary from month to month with obviously spatial heterogeneity.

  15. Ground surface temperature and continental heat gain: uncertainties from underground

    International Nuclear Information System (INIS)

    Beltrami, Hugo; Matharoo, Gurpreet S; Smerdon, Jason E

    2015-01-01

    Temperature changes at the Earth's surface propagate and are recorded underground as perturbations to the equilibrium thermal regime associated with the heat flow from the Earth's interior. Borehole climatology is concerned with the analysis and interpretation of these downward propagating subsurface temperature anomalies in terms of surface climate. Proper determination of the steady-state geothermal regime is therefore crucial because it is the reference against which climate-induced subsurface temperature anomalies are estimated. Here, we examine the effects of data noise on the determination of the steady-state geothermal regime of the subsurface and the subsequent impact on estimates of ground surface temperature (GST) history and heat gain. We carry out a series of Monte Carlo experiments using 1000 Gaussian noise realizations and depth sections of 100 and 200 m as for steady-state estimates depth intervals, as well as a range of data sampling intervals from 10 m to 0.02 m. Results indicate that typical uncertainties for 50 year averages are on the order of ±0.02 K for the most recent 100 year period. These uncertainties grow with decreasing sampling intervals, reaching about ±0.1 K for a 10 m sampling interval under identical conditions and target period. Uncertainties increase for progressively older periods, reaching ±0.3 K at 500 years before present for a 10 m sampling interval. The uncertainties in reconstructed GST histories for the Northern Hemisphere for the most recent 50 year period can reach a maximum of ±0.5 K in some areas. We suggest that continuous logging should be the preferred approach when measuring geothermal data for climate reconstructions, and that for those using the International Heat Flow Commission database for borehole climatology, the steady-state thermal conditions should be estimated from boreholes as deep as possible and using a large fitting depth range (∼100 m). (letter)

  16. 3D Surface Temperature Measurement of Plant Canopies Using Photogrammetry Techniques From A UAV.

    Science.gov (United States)

    Irvine, M.; Lagouarde, J. P.

    2017-12-01

    Surface temperature of plant canopies and within canopies results from the coupling of radiative and energy exchanges processes which govern the fluxes at the interface soil-plant-atmosphere. As a key parameter, surface temperature permits the estimation of canopy exchanges using processes based modeling methods. However detailed 3D surface temperature measurements or even profile surface temperature measurements are rarely made as they have inherent difficulties. Such measurements would greatly improve multi-level canopy models such as NOAH (Chen and Dudhia 2001) or MuSICA (Ogée and Brunet 2002, Ogée et al 2003) where key surface temperature estimations, at present, are not tested. Additionally, at larger scales, canopy structure greatly influences satellite based surface temperature measurements as the structure impacts the observations which are intrinsically made at varying satellite viewing angles and solar heights. In order to account for these differences, again accurate modeling is required such as through the above mentioned multi-layer models or with several source type models such as SCOPE (Van der Tol 2009) in order to standardize observations. As before, in order to validate these models, detailed field observations are required. With the need for detailed surface temperature observations in mind we have planned a series of experiments over non-dense plant canopies to investigate the use of photogrammetry techniques. Photogrammetry is normally used for visible wavelengths to produce 3D images using cloud point reconstruction of aerial images (for example Dandois and Ellis, 2010, 2013 over a forest). From these cloud point models it should be possible to establish 3D plant surface temperature images when using thermal infrared array sensors. In order to do this our experiments are based on the use of a thermal Infrared camera embarked on a UAV. We adapt standard photogrammetry to account for limits imposed by thermal imaginary, especially the low

  17. Integrated Temperature Sensors based on Heat Diffusion

    NARCIS (Netherlands)

    Van Vroonhoven, C.P.L.

    2015-01-01

    This thesis describes the theory, design and implementation of a new class of integrated temperature sensors, based on heat diffusion. In such sensors, temperature is sensed by measuring the time it takes for heat to diffuse through silicon. An on-chip thermal delay can be determined by geometry and

  18. Spatial-temporal analysis of building surface temperatures in Hung Hom

    Science.gov (United States)

    Zeng, Ying; Shen, Yueqian

    2015-12-01

    This thesis presents a study on spatial-temporal analysis of building surface temperatures in Hung Hom. Observations were collected from Aug 2013 to Oct 2013 at a 30-min interval, using iButton sensors (N=20) covering twelve locations in Hung Hom. And thermal images were captured in PolyU from 05 Aug 2013 to 06 Aug 2013. A linear regression model of iButton and thermal records is established to calibrate temperature data. A 3D modeling system is developed based on Visual Studio 2010 development platform, using ArcEngine10.0 component, Microsoft Access 2010 database and C# programming language. The system realizes processing data, spatial analysis, compound query and 3D face temperature rendering and so on. After statistical analyses, building face azimuths are found to have a statistically significant relationship with sun azimuths at peak time. And seasonal building temperature changing also corresponds to the sun angle and sun azimuth variations. Building materials are found to have a significant effect on building surface temperatures. Buildings with lower albedo materials tend to have higher temperatures and larger thermal conductivity material have significant diurnal variations. For the geographical locations, the peripheral faces of campus have higher temperatures than the inner faces during day time and buildings located at the southeast are cooler than the western. Furthermore, human activity is found to have a strong relationship with building surface temperatures through weekday and weekend comparison.

  19. Theoretical algorithms for satellite-derived sea surface temperatures

    Science.gov (United States)

    Barton, I. J.; Zavody, A. M.; O'Brien, D. M.; Cutten, D. R.; Saunders, R. W.; Llewellyn-Jones, D. T.

    1989-03-01

    Reliable climate forecasting using numerical models of the ocean-atmosphere system requires accurate data sets of sea surface temperature (SST) and surface wind stress. Global sets of these data will be supplied by the instruments to fly on the ERS 1 satellite in 1990. One of these instruments, the Along-Track Scanning Radiometer (ATSR), has been specifically designed to provide SST in cloud-free areas with an accuracy of 0.3 K. The expected capabilities of the ATSR can be assessed using transmission models of infrared radiative transfer through the atmosphere. The performances of several different models are compared by estimating the infrared brightness temperatures measured by the NOAA 9 AVHRR for three standard atmospheres. Of these, a computationally quick spectral band model is used to derive typical AVHRR and ATSR SST algorithms in the form of linear equations. These algorithms show that a low-noise 3.7-μm channel is required to give the best satellite-derived SST and that the design accuracy of the ATSR is likely to be achievable. The inclusion of extra water vapor information in the analysis did not improve the accuracy of multiwavelength SST algorithms, but some improvement was noted with the multiangle technique. Further modeling is required with atmospheric data that include both aerosol variations and abnormal vertical profiles of water vapor and temperature.

  20. Urban percent impervious surface and its relationship with land surface temperature in Yantai City, China

    International Nuclear Information System (INIS)

    Yu, Xinyang; Lu, Changhe

    2014-01-01

    This study investigated percent impervious surface area (PISA) extracted by a four-endmember normalized spectral mixture analysis (NSMA) method and evaluated the reliability of PISA as an indicator of land surface temperature (LST). Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images for Yantai city, eastern China obtained from USGS were used as the main data source. The results demonstrated that four-endmember NSMA method performed better than the typical three-endmember one, and there was a strong linear relationship between LST and PISA for the two images, which suggest percent impervious surface area provides an alternative parameter for analyzing LST quantitatively in urban areas

  1. Sound beam manipulation based on temperature gradients

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Feng [Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China); School of Physics & Electronic Engineering, Changshu Institute of Technology, Changshu 215500 (China); Quan, Li; Liu, Xiaozhou, E-mail: xzliu@nju.edu.cn; Gong, Xiufen [Key Laboratory of Modern Acoustics, Institute of Acoustics and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)

    2015-10-28

    Previous research with temperature gradients has shown the feasibility of controlling airborne sound propagation. Here, we present a temperature gradients based airborne sound manipulation schemes: a cylindrical acoustic omnidirectional absorber (AOA). The proposed AOA has high absorption performance which can almost completely absorb the incident wave. Geometric acoustics is used to obtain the refractive index distributions with different radii, which is then utilized to deduce the desired temperature gradients. Since resonant units are not applied in the scheme, its working bandwidth is expected to be broadband. The scheme is temperature-tuned and easy to realize, which is of potential interest to fields such as noise control or acoustic cloaking.

  2. Decadal trends in Red Sea maximum surface temperature.

    Science.gov (United States)

    Chaidez, V; Dreano, D; Agusti, S; Duarte, C M; Hoteit, I

    2017-08-15

    Ocean warming is a major consequence of climate change, with the surface of the ocean having warmed by 0.11 °C decade -1 over the last 50 years and is estimated to continue to warm by an additional 0.6 - 2.0 °C before the end of the century 1 . However, there is considerable variability in the rates experienced by different ocean regions, so understanding regional trends is important to inform on possible stresses for marine organisms, particularly in warm seas where organisms may be already operating in the high end of their thermal tolerance. Although the Red Sea is one of the warmest ecosystems on earth, its historical warming trends and thermal evolution remain largely understudied. We characterized the Red Sea's thermal regimes at the basin scale, with a focus on the spatial distribution and changes over time of sea surface temperature maxima, using remotely sensed sea surface temperature data from 1982 - 2015. The overall rate of warming for the Red Sea is 0.17 ± 0.07 °C decade -1 , while the northern Red Sea is warming between 0.40 and 0.45 °C decade -1 , all exceeding the global rate. Our findings show that the Red Sea is fast warming, which may in the future challenge its organisms and communities.

  3. Decadal trends in Red Sea maximum surface temperature

    KAUST Repository

    Chaidez, Veronica

    2017-08-09

    Ocean warming is a major consequence of climate change, with the surface of the ocean having warmed by 0.11 °C decade-1 over the last 50 years and is estimated to continue to warm by an additional 0.6 - 2.0 °C before the end of the century1. However, there is considerable variability in the rates experienced by different ocean regions, so understanding regional trends is important to inform on possible stresses for marine organisms, particularly in warm seas where organisms may be already operating in the high end of their thermal tolerance. Although the Red Sea is one of the warmest ecosystems on earth, its historical warming trends and thermal evolution remain largely understudied. We characterized the Red Sea\\'s thermal regimes at the basin scale, with a focus on the spatial distribution and changes over time of sea surface temperature maxima, using remotely sensed sea surface temperature data from 1982 - 2015. The overall rate of warming for the Red Sea is 0.17 ± 0.07 °C decade-1, while the northern Red Sea is warming between 0.40 and 0.45 °C decade-1, all exceeding the global rate. Our findings show that the Red Sea is fast warming, which may in the future challenge its organisms and communities.

  4. Decadal trends in Red Sea maximum surface temperature

    KAUST Repository

    Chaidez, Veronica; Dreano, Denis; Agusti, Susana; Duarte, Carlos M.; Hoteit, Ibrahim

    2017-01-01

    Ocean warming is a major consequence of climate change, with the surface of the ocean having warmed by 0.11 °C decade-1 over the last 50 years and is estimated to continue to warm by an additional 0.6 - 2.0 °C before the end of the century1. However, there is considerable variability in the rates experienced by different ocean regions, so understanding regional trends is important to inform on possible stresses for marine organisms, particularly in warm seas where organisms may be already operating in the high end of their thermal tolerance. Although the Red Sea is one of the warmest ecosystems on earth, its historical warming trends and thermal evolution remain largely understudied. We characterized the Red Sea's thermal regimes at the basin scale, with a focus on the spatial distribution and changes over time of sea surface temperature maxima, using remotely sensed sea surface temperature data from 1982 - 2015. The overall rate of warming for the Red Sea is 0.17 ± 0.07 °C decade-1, while the northern Red Sea is warming between 0.40 and 0.45 °C decade-1, all exceeding the global rate. Our findings show that the Red Sea is fast warming, which may in the future challenge its organisms and communities.

  5. A Study on the Relationships among Surface Variables to Adjust the Height of Surface Temperature for Data Assimilation.

    Science.gov (United States)

    Kang, J. H.; Song, H. J.; Han, H. J.; Ha, J. H.

    2016-12-01

    The observation processing system, KPOP (KIAPS - Korea Institute of Atmospheric Prediction Systems - Package for Observation Processing) have developed to provide optimal observations to the data assimilation system for the KIAPS Integrated Model (KIM). Currently, the KPOP has capable of processing almost all of observations for the KMA (Korea Meteorological Administration) operational global data assimilation system. The height adjustment of SURFACE observations are essential for the quality control due to the difference in height between observation station and model topography. For the SURFACE observation, it is usual to adjust the height using lapse rate or hypsometric equation, which decides values mainly depending on the difference of height. We have a question of whether the height can be properly adjusted following to the linear or exponential relationship solely with regard to the difference of height, with disregard the atmospheric conditions. In this study, firstly we analyse the change of surface variables such as temperature (T2m), pressure (Psfc), humidity (RH2m and Q2m), and wind components (U and V) according to the height difference. Additionally, we look further into the relationships among surface variables . The difference of pressure shows a strong linear relationship with difference of height. But the difference of temperature according to the height shows a significant correlation with difference of relative humidity than with the height difference. A development of reliable model for the height-adjustment of surface temperature is being undertaken based on the preliminary results.

  6. Temperature-mediated transition from Dyakonov-Tamm surface waves to surface-plasmon-polariton waves

    Science.gov (United States)

    Chiadini, Francesco; Fiumara, Vincenzo; Mackay, Tom G.; Scaglione, Antonio; Lakhtakia, Akhlesh

    2017-08-01

    The effect of changing the temperature on the propagation of electromagnetic surface waves (ESWs), guided by the planar interface of a homogeneous isotropic temperature-sensitive material (namely, InSb) and a temperature-insensitive structurally chiral material (SCM) was numerically investigated in the terahertz frequency regime. As the temperature rises, InSb transforms from a dissipative dielectric material to a dissipative plasmonic material. Correspondingly, the ESWs transmute from Dyakonov-Tamm surface waves into surface-plasmon-polariton waves. The effects of the temperature change are clearly observed in the phase speeds, propagation distances, angular existence domains, multiplicity, and spatial profiles of energy flow of the ESWs. Remarkably large propagation distances can be achieved; in such instances the energy of an ESW is confined almost entirely within the SCM. For certain propagation directions, simultaneous excitation of two ESWs with (i) the same phase speeds but different propagation distances or (ii) the same propagation distances but different phase speeds are also indicated by our results.

  7. Versatile microcomputer-based temperature controller

    International Nuclear Information System (INIS)

    Yarberry, V.R.

    1980-09-01

    The wide range of thermal responses required in laboratory and scientific equipment requires a temperature controller with a great deal of flexibility. While a number of analog temperature controllers are commercially available, they have certain limitations, such as inflexible parameter control or insufficient precision. Most lack digital interface capabilities--a necessity when the temperature controller is part of a computer-controlled automatic data acquisition system. We have developed an extremely versatile microcomputer-based temperature controller to fulfill this need in a variety of equipment. The control algorithm used allows optimal tailoring of parameters to control overshoot, response time, and accuracy. This microcomputer-based temperature controller can be used as a standalone instrument (with a teletype used to enter para-meters), or it can be integrated into a data acquisition system

  8. Indonesia sea surface temperature from TRMM Microwave Imaging (TMI) sensor

    Science.gov (United States)

    Marini, Y.; Setiawan, K. T.

    2018-05-01

    We analysis the Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI) data to monitor the sea surface temperature (SST) of Indonesia waters for a decade of 2005-2014. The TMI SST data shows the seasonal and interannual SST in Indonesian waters. In general, the SST average was highest in March-May period with SST average was 29.4°C, and the lowest was in June – August period with the SST average was 28.5°C. The monthly SST average fluctuation of Indonesian waters for 10 years tends to increase. The lowest SST average of Indonesia occurred in August 2006 with the SST average was 27.6° C, while the maximum occurred in May 2014 with the monthly SST average temperature was 29.9 ° C.

  9. Classically exact surface diffusion constants at arbitrary temperature

    International Nuclear Information System (INIS)

    Voter, A.F.; Cohen, J.M.

    1989-01-01

    An expression is presented for computing the classical diffusion constant of a point defect (e.g., an adatom) in an infinite lattice of binding sites at arbitrary temperature. The transition state theory diffusion constant is simply multiplied by a dynamical correction factor that is computed from short-time classical trajectories initiated at the site boundaries. The time scale limitations of direct molecular dynamics are thus avoided in the low- and middle-temperature regimes. The expression results from taking the time derivative of the particle mean-square displacement in the lattice-discretized coordinate system. Applications are presented for surface diffusion on fcc(100) and fcc(111) Lennard-Jones crystal faces

  10. Sea surface temperature contributes to marine crocodylomorph evolution.

    Science.gov (United States)

    Martin, Jeremy E; Amiot, Romain; Lécuyer, Christophe; Benton, Michael J

    2014-08-18

    During the Mesozoic and Cenozoic, four distinct crocodylomorph lineages colonized the marine environment. They were conspicuously absent from high latitudes, which in the Mesozoic were occupied by warm-blooded ichthyosaurs and plesiosaurs. Despite a relatively well-constrained stratigraphic distribution, the varying diversities of marine crocodylomorphs are poorly understood, because their extinctions neither coincided with any major biological crises nor with the advent of potential competitors. Here we test the potential link between their evolutionary history in terms of taxic diversity and two abiotic factors, sea level variations and sea surface temperatures (SST). Excluding Metriorhynchoidea, which may have had a peculiar ecology, significant correlations obtained between generic diversity and estimated Tethyan SST suggest that water temperature was a driver of marine crocodylomorph diversity. Being most probably ectothermic reptiles, these lineages colonized the marine realm and diversified during warm periods, then declined or became extinct during cold intervals.

  11. THE EFFECT OF ACTIVATED CARBON SURFACE MOISTURE ON LOW TEMPERATURE MERCURY ADSORPTION

    Science.gov (United States)

    Experiments with elemental mercury (Hg0) adsorption by activated carbons were performed using a bench-scale fixed-bed reactor at room temperature (27 degrees C) to determine the role of surface moisture in capturing Hg0. A bituminous-coal-based activated carbon (BPL) and an activ...

  12. Cloud tolerance of remote sensing technologies to measure land surface temperature

    Science.gov (United States)

    Conventional means to estimate land surface temperature (LST) from space relies on the thermal infrared (TIR) spectral window and is limited to cloud-free scenes. To also provide LST estimates during periods with clouds, a new method was developed to estimate LST based on passive microwave (MW) obse...

  13. Study of Volcanic Activity at Different Time Scales Using Hypertemporal Land Surface Temperature Data

    NARCIS (Netherlands)

    Pavlidou, Efthymia; Hecker, Chris; van der Werff, Harald; van der Meijder, Mark

    2017-01-01

    We apply a method for detecting subtle spatiotemporal signal fluctuations to monitor volcanic activity. Whereas midwave infrared data are commonly used for volcanic hot spot detection, our approach utilizes hypertemporal longwave infrared-based land surface temperature (LST) data. Using LST data of

  14. Thermal crackling: study of the mechanical effects of quick temperature fluctuations on metallic surfaces

    International Nuclear Information System (INIS)

    Pradel, P.

    1984-05-01

    After a brief overview of the thermohydraulical conditions of liquid sodium leading to important temperature fluctuations near the metallic surfaces, the author examines the transfer modes of these fluctuations in the structure thickness and the long term mechanical effects. Dimensioning models based on thermal and metallurgical properties are under study for structures subject to such sodium loads [fr

  15. Finite Elements on Point Based Surfaces

    NARCIS (Netherlands)

    Clarenz, U.; Rumpf, M.; Telea, A.

    2004-01-01

    We present a framework for processing point-based surfaces via partial differential equations (PDEs). Our framework efficiently and effectively brings well-known PDE-based processing techniques to the field of point-based surfaces. Our method is based on the construction of local tangent planes and

  16. Static Formation Temperature Prediction Based on Bottom Hole Temperature

    Directory of Open Access Journals (Sweden)

    Changwei Liu

    2016-08-01

    Full Text Available Static formation temperature (SFT is required to determine the thermophysical properties and production parameters in geothermal and oil reservoirs. However, it is not easy to determine SFT by both experimental and physical methods. In this paper, a mathematical approach to predicting SFT, based on a new model describing the relationship between bottom hole temperature (BHT and shut-in time, has been proposed. The unknown coefficients of the model were derived from the least squares fit by the particle swarm optimization (PSO algorithm. Additionally, the ability to predict SFT using a few BHT data points (such as the first three, four, or five points of a data set was evaluated. The accuracy of the proposed method to predict SFT was confirmed by a deviation percentage less than ±4% and a high regression coefficient R2 (>0.98. The proposed method could be used as a practical tool to predict SFT in both geothermal and oil wells.

  17. Measurement of a surface heat flux and temperature

    Science.gov (United States)

    Davis, R. M.; Antoine, G. J.; Diller, T. E.; Wicks, A. L.

    1994-04-01

    The Heat Flux Microsensor is a new sensor which was recently patented by Virginia Tech and is just starting to be marketed by Vatell Corp. The sensor is made using the thin-film microfabrication techniques directly on the material that is to be measured. It consists of several thin-film layers forming a differential thermopile across a thermal resistance layer. The measured heat flux q is proportional to the temperature difference across the resistance layer q= k(sub g)/delta(sub g) x (t(sub 1) - T(sub 2)), where k(sub g) is the thermal conductivity and delta (sub g) is the thickness of the thermal resistance layer. Because the gages are sputter coated directly onto the surface, their total thickness is less than 2 micrometers, which is two orders of magnitude thinner than previous gages. The resulting temperature difference across the thermal resistance layer (delta is less than 1 micrometer) is very small even at high heat fluxes. To generate a measurable signal many thermocouple pairs are put in series to form a differential thermopile. The combination of series thermocouple junctions and thin-film design creates a gage with very attractive characteristics. It is not only physically non-intrusive to the flow, but also causes minimal disruption of the surface temperature. Because it is so thin, the response time is less than 20 microsec. Consequently, the frequency response is flat from 0 to over 50 kHz. Moreover, the signal of the Heat Flux Microsensor is directly proportional to the heat flux. Therefore, it can easily be used in both steady and transient flows, and it measures both the steady and unsteady components of the surface heat flux. A version of the Heat Flux Microsensor has been developed to meet the harsh demands of combustion environments. These gages use platinum and platinum-10 percent rhodium as the thermoelectric materials. The thermal resistance layer is silicon monoxide and a protective coating of Al2O3 is deposited on top of the sensor. The

  18. Surface temperatures in the polar regions from Nimbus 7 temperature humidity infrared radiometer

    Science.gov (United States)

    Comiso, Josefino C.

    1994-01-01

    Monthly surface temperatures in the Arctic and Antarctic regions have been derived from the 11.5 micrometer thermal infrared channel of the Nimbus 7 temperature humidity infrared radiometer (THIR) for a whole year in 1979 and for a winter and a summer month from 1980 through 1985. The data set shows interannual variability and provides spatial details that allow identification of temperature patterns over sea ice and ice sheet surfaces. For example, the coldest spot in the southern hemisphere is observed to be consistently in the Antarctic plateau in the southern hemisphere, while that in the northern hemisphere is usually located in Greenland, or one of three other general areas: Siberia, the central Arctic, or the Canadian Archipelago. Also, in the southern hemisphere, the amplitude of the seasonal fluctuation of ice sheet temperatures is about 3 times that of sea ice, while in the northern hemisphere, the corresponding fluctuations for the two surfaces are about the same. The main sources of error in the retrieval are cloud and other atmospheric effects. These were minimized by first choosing the highest radiance value from the set of measurements during the day taken within a 30 km by 30 km grid of each daily map. Then the difference of daily maps was taken and where the difference is greater than a certain threshold (which in this case is 12 C), the data element is deleted. Overall, the monthly maps derived from the resulting daily maps are spatially and temporally consistent, are coherent with the topograph y of the Antarctic continent and the location of the sea ice edge, and are in qualitative agreement with climatological data. Quantitatively, THIR data are in good agreement with Antarctic ice sheet surface air temperature station data with a correlation coefficient of 0.997 and a standard deviation of 2.0 C. The absolute values are not as good over the sea ice edges, but a comparison with Russian 2-m drift station temperatures shows very high correlation

  19. The Role of Surface Protection for High-Temperature Performance of TiAl Alloys

    Science.gov (United States)

    Schütze, Michael

    2017-12-01

    In the temperature range where TiAl alloys are currently being used in jet engine and automotive industries, surface reaction with the operating environment is not yet a critical issue. Surface treatment may, however, be needed in order to provide improved abrasion resistance. Development routes currently aim at a further increase in operation temperatures in gas turbines up to 800°C and higher, and in automotive applications for turbocharger rotors, even up to 1050°C. In this case, oxidation rates may reach levels where significant metal consumption of the load-bearing cross-section can occur. Another possibly even more critical issue can be high-temperature-induced oxygen and nitrogen up-take into the metal subsurface zone with subsequent massive ambient temperature embrittlement. Solutions for these problems are based on a deliberate phase change of the metal subsurface zone by diffusion treatments and by using effects such as the halogen effect to change the oxidation mechanism at high temperatures. Other topics of relevance for the use of TiAl alloys in high-temperature applications can be high-temperature abrasion resistance, thermal barrier coatings on TiAl and surface quality in additive manufacturing, in all these cases-focusing on the role of the operation environment. This paper addresses the recent developments in these areas and the requirements for future work.

  20. Temperature effect on uranium retention onto Zr2O(PO4)2 surface

    International Nuclear Information System (INIS)

    Almazan Torres, M.G.

    2007-03-01

    Uranium sorption onto Zr 2 O(PO 4 ) 2 has been studied between 298 K and 363 K, in 0.1 M NaClO 4 medium. Potentiometric titrations were realized to determine temperature dependency of the acid-base properties (pH(pcn), acidity constants). Classical batch experiments were performed at different temperatures. The sorption experiments revealed that the uranium sorption onto Zr 2 O(PO 4 ) 2 is favoured with the temperature. Structural characterization of the surface complexes was performed by both Time-Resolved Laser-Induced Fluorescence (TRLIF) and EXAFS spectroscopy. The TRLIF measurements vs. temperature revealed two uranyl surface complexes. No influence of the temperature onto the nature surface complex was observed. The EXAFS analysis showed a splitting of the equatorial oxygen atoms in two shells, corresponding to uranyl bidentate, inner-sphere complexes. The obtained structural uranyl surface complex information was used to simulate (using a constant capacitance model) the sorption edges. The proposed complexes equilibrium model consists of the following surface complexes: (ZrOH) 2 UO 2 2+ and (PO) 2 UO 2 . Besides the stability constants for the surface complexes, the thermodynamic parameters ΔH 0 and ΔS 0 were determined using the van't Hoff equation. The enthalpy values associated to the U(VI) retention onto Zr 2 O(PO 4 ) 2 , determined by the temperature dependence of the stability constants, testify that the formation of the complex (PO) 2 UO 2 (55 kJ/mol) is endothermic, while no influence of the temperature was observed for the formation of the complex (ZrOH) 2 UO 2 2+ . The adsorption reaction of the last complex is then driven by entropy. In addition, calorimetric measurements of uranium sorption onto Zr 2 O(PO 4 ) 2 were carried out to directly quantify the enthalpy associated to the retention processes. (author)

  1. Three modes of interdecadal trends in sea surface temperature and sea surface height

    Science.gov (United States)

    Gnanadesikan, A.; Pradal, M.

    2013-12-01

    It might be thought that sea surface height and sea surface temperature would be tightly related. We show that this is not necessarily the case on a global scale. We analysed this relationship in a suite of coupled climate models run under 1860 forcing conditions. The models are low-resolution variants of the GFDL Earth System Model, reported in Galbraith et al. (J. Clim. 2011). 1. Correlated changes in global sea surface height and global sea surface temperature. This mode corresponds to opening and closing of convective chimneys in the Southern Ocean. As the Southern Ocean destratifies, sea ice formation is suppressed during the winter and more heat is taken up during the summer. This mode of variability is highly correlated with changes in the top of the atmosphere radiative budget and weakly correlated with changes in the deep ocean circulation. 2. Uncorrelated changes in global sea surface height and global sea surface temperature. This mode of variability is associated with interdecadal variabliity in tropical winds. Changes in the advective flux of heat to the surface ocean play a critical role in driving these changes, which also result in significant local changes in sea level. Changes sea ice over the Southern Ocean still result in changes in solar absorption, but these are now largely cancelled by changes in outgoing longwave radiation. 3. Anticorrelated changes in global sea surface height and global sea surface temperatures. By varying the lateral diffusion coefficient in the ocean model, we are able to enhance and suppress convection in the Southern and Northern Pacific Oceans. Increasing the lateral diffusion coefficients shifts the balance sources of deep water away from the warm salty deep water of the North Atlantic and towards cold fresh deep water from the other two regions. As a result, even though the planet as a whole warms, the deep ocean cools and sea level falls, with changes of order 30 cm over 500 years. The increase in solar absorption

  2. Room temperature Cu-Cu direct bonding using surface activated bonding method

    International Nuclear Information System (INIS)

    Kim, T.H.; Howlader, M.M.R.; Itoh, T.; Suga, T.

    2003-01-01

    Thin copper (Cu) films of 80 nm thickness deposited on a diffusion barrier layered 8 in. silicon wafers were directly bonded at room temperature using the surface activated bonding method. A low energy Ar ion beam of 40-100 eV was used to activate the Cu surface prior to bonding. Contacting two surface-activated wafers enables successful Cu-Cu direct bonding. The bonding process was carried out under an ultrahigh vacuum condition. No thermal annealing was required to increase the bonding strength since the bonded interface was strong enough at room temperature. The chemical constitution of the Cu surface was examined by Auger electron spectroscope. It was observed that carbon-based contaminations and native oxides on copper surface were effectively removed by Ar ion beam irradiation for 60 s without any wet cleaning processes. An atomic force microscope study shows that the Ar ion beam process causes no surface roughness degradation. Tensile test results show that high bonding strength equivalent to bulk material is achieved at room temperature. The cross-sectional transmission electron microscope observations reveal the presence of void-free bonding interface without intermediate layer at the bonded Cu surfaces

  3. Surface alloying of nickel based superalloys by laser

    International Nuclear Information System (INIS)

    Rodriguez, G.P.; Garcia, I.; Damborenea, J.J. de

    1998-01-01

    Ni based superalloys present a high oxidation resistance at high temperature as well as good mechanical properties. But new technology developments force to research in this materials to improve their properties at high temperature. In this work, two Ni based superalloys (Nimonic 80A and Inconel 600) were surface alloyed with aluminium using a high power laser. SEM and EDX were used to study the microstructure of the obtained coatings. Alloyed specimens were tested at 1.273 K between 24 and 250 h. Results showed the generation of a protective and continuous coating of alumina on the laser treated specimens surface that can improve oxidation resistance. (Author) 8 refs

  4. Mesoscale surface equivalent temperature (T E) for East Central USA

    Science.gov (United States)

    Younger, Keri; Mahmood, Rezaul; Goodrich, Gregory; Pielke, Roger A.; Durkee, Joshua

    2018-04-01

    The purpose of this research is to investigate near surface mesoscale equivalent temperatures (T E) in Kentucky (located in east central USA) and potential land cover influences. T E is a measure of the moist enthalpy composed of the dry bulb temperature, T, and absolute humidity. Kentucky presents a unique opportunity to perform a study of this kind because of the observational infrastructure provided by the Kentucky Mesonet (www.kymesonet.org). This network maintains 69 research-grade, in-situ weather and climate observing stations across the Commonwealth. Equivalent temperatures were calculated utilizing high-quality observations from 33 of these stations. In addition, the Kentucky Mesonet offers higher spatial and temporal resolution than previous research on this topic. As expected, the differences (T E - T) were greatest in the summer (smallest in the winter), with an average of 35 °C (5 °C). In general, the differences were found to be the largest in the western climate division. This is attributed to agricultural land use and poorly drained land. These differences are smaller during periods of drought, signifying less influence of moisture.

  5. Impact of vegetation growth on urban surface temperature distribution

    International Nuclear Information System (INIS)

    Buyadi, S N A; Mohd, W M N W; Misni, A

    2014-01-01

    Earlier studies have indicated that, the temperature distribution in the urban area is significantly warmer than its surrounding suburban areas. The process of urbanization has created urban heat island (UHI). As a city expands, trees are cut down to accommodate commercial development, industrial areas, roads, and suburban growth. Trees or green areas normally play a vital role in mitigating the UHI effects especially in regulating high temperature in saturated urban areas. This study attempts to assess the effects of vegetation growth on land surface temperature (LST) distribution in urban areas. An area within the City of Shah Alam, Selangor has been selected as the study area. Land use/land cover and LST maps of two different dates are generated from Landsat 5 TM images of the year 1991 and 2009. Only five major land cover classes are considered in this study. Mono-window algorithm is used to generate the LST maps. Landsat 5 TM images are also used to generate the NDVI maps. Results from this study have shown that there are significant land use changes within the study area. Although the conversion of green areas into residential and commercial areas significantly increase the LST, matured trees will help to mitigate the effects of UHI

  6. Aquarius Reflector Surface Temperature Monitoring Test and Analysis

    Science.gov (United States)

    Abbott, Jamie; Lee, Siu-Chun; Becker, Ray

    2008-01-01

    The presentation addresses how to infer the front side temperatures for the Aquarius L-band reflector based upon backside measurement sites. Slides discussing the mission objectives and design details are at the same level found on typical project outreach websites and in conference papers respectively. The test discussion provides modest detail of an ordinary thermal balance test using mockup hardware. The photographs show an off-Lab vacuum chamber facility with no compromising details.

  7. Implant Surface Temperature Changes during Er:YAG Laser Irradiation with Different Cooling Systems.

    Directory of Open Access Journals (Sweden)

    Abbas Monzavi

    2014-04-01

    Full Text Available Peri-implantitis is one of the most common reasons for implant failure. Decontamination of infected implant surfaces can be achieved effectively by laser irradiation; although the associated thermal rise may cause irreversible bone damage and lead to implant loss. Temperature increments of over 10ºC during laser application may suffice for irreversible bone damage.The purpose of this study was to evaluate the temperature increment of implant surface during Er:YAG laser irradiation with different cooling systems.Three implants were placed in a resected block of sheep mandible and irradiated with Er:YAG laser with 3 different cooling systems namely water and air spray, air spray alone and no water or air spray. Temperature changes of the implant surface were monitored during laser irradiation with a K-type thermocouple at the apical area of the fixture.In all 3 groups, the maximum temperature rise was lower than 10°C. Temperature changes were significantly different with different cooling systems used (P<0.001.Based on the results, no thermal damage was observed during implant surface decontamination by Er:YAG laser with and without refrigeration. Thus, Er:YAG laser irradiation can be a safe method for treatment of periimplantitis.

  8. Global Land Surface Temperature From the Along-Track Scanning Radiometers

    Science.gov (United States)

    Ghent, D. J.; Corlett, G. K.; Göttsche, F.-M.; Remedios, J. J.

    2017-11-01

    The Leicester Along-Track Scanning Radiometer (ATSR) and Sea and Land Surface Temperature Radiometer (SLSTR) Processor for LAnd Surface Temperature (LASPLAST) provides global land surface temperature (LST) products from thermal infrared radiance data. In this paper, the state-of-the-art version of LASPLAST, as deployed in the GlobTemperature project, is described and applied to data from the Advanced Along-Track Scanning Radiometer (AATSR). The LASPLAST retrieval formulation for LST is a nadir-only, two-channel, split-window algorithm, based on biome classification, fractional vegetation, and across-track water vapor dependences. It incorporates globally robust retrieval coefficients derived using highly sampled atmosphere profiles. LASPLAST benefits from appropriate spatial resolution auxiliary information and a new probabilistic-based cloud flagging algorithm. For the first time for a satellite-derived LST product, pixel-level uncertainties characterized in terms of random, locally correlated, and systematic components are provided. The new GlobTemperature GT_ATS_2P Version 1.0 product has been validated for 1 year of AATSR data (2009) against in situ measurements acquired from "gold standard reference" stations: Gobabeb, Namibia, and Evora, Portugal; seven Surface Radiation Budget stations, and the Atmospheric Radiation Measurement station at Southern Great Plains. These data show average absolute biases for the GT_ATS_2P Version 1.0 product of 1.00 K in the daytime and 1.08 K in the nighttime. The improvements in data provenance including better accuracy, fully traceable retrieval coefficients, quantified uncertainty, and more detailed information in the new harmonized format of the GT_ATS_2P product will allow for more significant exploitation of the historical LST data record from the ATSRs and a valuable near-real-time service from the Sea and Land Surface Temperature Radiometers (SLSTRs).

  9. GHRSST Level 4 DMI_OI Global Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the Danish...

  10. GHRSST Level 4 MUR North America Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced as a retrospective dataset at the JPL Physical...

  11. GHRSST Level 4 OSPO Global Nighttime Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Office of...

  12. GHRSST Level 4 AVHRR_AMSR_OI Global Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.25 degree grid at the NOAA...

  13. GHRSST Level 4 ODYSSEA Mediterranean Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  14. GHRSST Level 4 G1SST Global Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the JPL OurOcean...

  15. GHRSST Level 4 MW_OI Global Foundation Sea Surface Temperature analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.25 degree grid at Remote Sensing...

  16. GHRSST Level 4 K10_SST Global 1 meter Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Naval...

  17. GHRSST Level 4 EUR Mediterranean Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily by Ifremer/CERSAT (France) using optimal...

  18. GHRSST Level 4 ODYSSEA Eastern Central Pacific Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  19. GHRSST Level 4 ODYSSEA Global Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  20. GHRSST Level 4 OSPO Global Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Office of...

  1. GHRSST Level 4 GAMSSA Global Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Australian Bureau...

  2. GHRSST Level 4 RAMSSA Australian Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Australian Bureau...

  3. GHRSST Level 4 OSTIA Global Foundation Sea Surface Temperature Analysis (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the UK Met Office...

  4. Modeling the Impacts of Boreal Deforestation on the Near-Surface Temperature in European Russia

    Directory of Open Access Journals (Sweden)

    Zhihui Li

    2013-01-01

    Full Text Available Boreal deforestation plays an important role in affecting regional and global climate. In this study, the regional temperature variation induced by future boreal deforestation in European Russia boreal forest region was simulated based on future land cover change and the Weather Research and Forecasting (WRF model. This study firstly tested and validated the simulation results of the WRF model. Then the land cover datasets in different years (2000 as baseline year, 2010, and 2100 was used in the WRF model to explore the impacts of boreal deforestation on the near-surface temperature. The results indicated that the WRF model has good ability to simulate the temperature change in European Russia. The land cover change in European Russia boreal forest region, which will be characterized by the conversion from boreal forests to croplands (boreal deforestation in the future 100 years, will lead to significant change of the near-surface temperature. The regional annual temperature will decrease by 0.58°C in the future 100 years, resulting in cooling effects to some extent and making the near-surface temperature decrease in most seasons except the spring.

  5. A One-Source Approach for Estimating Land Surface Heat Fluxes Using Remotely Sensed Land Surface Temperature

    Directory of Open Access Journals (Sweden)

    Yongmin Yang

    2017-01-01

    Full Text Available The partitioning of available energy between sensible heat and latent heat is important for precise water resources planning and management in the context of global climate change. Land surface temperature (LST is a key variable in energy balance process and remotely sensed LST is widely used for estimating surface heat fluxes at regional scale. However, the inequality between LST and aerodynamic surface temperature (Taero poses a great challenge for regional heat fluxes estimation in one-source energy balance models. To address this issue, we proposed a One-Source Model for Land (OSML to estimate regional surface heat fluxes without requirements for empirical extra resistance, roughness parameterization and wind velocity. The proposed OSML employs both conceptual VFC/LST trapezoid model and the electrical analog formula of sensible heat flux (H to analytically estimate the radiometric-convective resistance (rae via a quartic equation. To evaluate the performance of OSML, the model was applied to the Soil Moisture-Atmosphere Coupling Experiment (SMACEX in United States and the Multi-Scale Observation Experiment on Evapotranspiration (MUSOEXE in China, using remotely sensed retrievals as auxiliary data sets at regional scale. Validated against tower-based surface fluxes observations, the root mean square deviation (RMSD of H and latent heat flux (LE from OSML are 34.5 W/m2 and 46.5 W/m2 at SMACEX site and 50.1 W/m2 and 67.0 W/m2 at MUSOEXE site. The performance of OSML is very comparable to other published studies. In addition, the proposed OSML model demonstrates similar skills of predicting surface heat fluxes in comparison to SEBS (Surface Energy Balance System. Since OSML does not require specification of aerodynamic surface characteristics, roughness parameterization and meteorological conditions with high spatial variation such as wind speed, this proposed method shows high potential for routinely acquisition of latent heat flux estimation

  6. SAGA GIS based processing of spatial high resolution temperature data

    International Nuclear Information System (INIS)

    Gerlitz, Lars; Bechtel, Benjamin; Kawohl, Tobias; Boehner, Juergen; Zaksek, Klemen

    2013-01-01

    Many climate change impact studies require surface and near surface temperature data with high spatial and temporal resolution. The resolution of state of the art climate models and remote sensing data is often by far to coarse to represent the meso- and microscale distinctions of temperatures. This is particularly the case for regions with a huge variability of topoclimates, such as mountainous or urban areas. Statistical downscaling techniques are promising methods to refine gridded temperature data with limited spatial resolution, particularly due to their low demand for computer capacity. This paper presents two downscaling approaches - one for climate model output and one for remote sensing data. Both are methodically based on the FOSS-GIS platform SAGA. (orig.)

  7. Temperature quenching in LAB based liquid scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, A.; Zuber, K. [Technische Universitaet Dresden, Institute for Nuclear- and Particle Physics, Dresden (Germany); Hans, S.; Yeh, M. [Brookhaven National Laboratory, Chemistry Devision, Upton, NY (United States); Junghans, A.R.; Koegler, T.; Wagner, A. [Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Krosigk, B. v. [Technische Universitaet Dresden, Institute for Nuclear- and Particle Physics, Dresden (Germany); University of British Columbia, Department of Physics and Astronomy, Vancouver, BC (Canada); Lozza, V. [Technische Universitaet Dresden, Institute for Nuclear- and Particle Physics, Dresden (Germany); Laboratorio de Instrumentacao e Fisica Experimental de Particulas, Lisboa (Portugal)

    2018-01-15

    The effect of temperature changes on the light output of LAB based liquid scintillator is investigated in a range from -5 to 30 C with α-particles and electrons in a small scale setup. Two PMTs observe the scintillator liquid inside a cylindrically shaped aluminum cuvette that is heated or cooled and the temperature dependent PMT sensitivity is monitored and corrected. The α-emitting isotopes in dissolved radon gas and in natural Samarium (bound to a LAB solution) excite the liquid scintillator mixtures and changes in light output with temperature variation are observed by fitting light output spectra. Furthermore, also changes in light output by compton electrons, which are generated from external calibration γ-ray sources, is analysed with varying temperature. Assuming a linear behaviour, a combined negative temperature coefficient of (-0.29 ± 0.01)%/ C is found. Considering hints for a particle type dependency, electrons show (-0.17 ± 0.02)%/ C, whereas the temperature dependency seems stronger for α-particles, with (-0.35 ± 0.03)%/ C. Due to a high sampling rate, a pulse shape analysis can be performed and shows an enhanced slow decay component at lower temperatures, pointing to reduced non-radiative triplet state de-excitations. (orig.)

  8. Daily Cycle of Air Temperature and Surface Temperature in Stone Forest

    Science.gov (United States)

    Wang, K.; Li, Y.; Wang, X.; Yuan, M.

    2013-12-01

    Urbanization is one of the most profound human activities that impact on climate change. In cities, where are highly artificial areas, the conflict between human activity and natural climate is particularly prominent. Urban areas always have the larger area of impervious land, the higher consumption of greenhouse gases, more emissions of anthropogenic heat and air pollution, all contribute to the urban warming phenomena. Understanding the mechanisms causing a variety of phenomena involved in the urban warming is critical to distinguish the anthropogenic effect and natural variation in the climate change. However, the exact dynamics of urban warming were poorly understood, and effective control strategies are not available. Here we present a study of the daily cycle of air temperature and surface temperature in Stone Forest. The specific heat of the stones in the Stone Forest and concrete of the man-made structures within the cities are approximate. Besides, the height of the Stone Forest and the height of buildings within the city are also similar. As a scenic area, the Stone Forest is being preserved and only opened for sightseeing. There is no anthropogenic heat, as well air pollution within the Stone Forest. The thermal environment in Stone Forest can be considered to be a simulation of thermal environment in the city, which can reveal the effect of man-made structures on urban thermal environment. We conducted the field studies and numerical analysis in the Stone Forest for 4 typical urban morphology and environment scenarios, including high-rise compact cities, low-rise sparse cities, garden cities and isolated single stone. Air temperature and relative humidity were measured every half an hour in 15 different locations, which within different spatial distribution of stones and can represent the four urban scenarios respectively. At the same time, an infrared camera was used to take thermal images and get the hourly surface temperatures of stones and

  9. New Temperature-based Models for Predicting Global Solar Radiation

    International Nuclear Information System (INIS)

    Hassan, Gasser E.; Youssef, M. Elsayed; Mohamed, Zahraa E.; Ali, Mohamed A.; Hanafy, Ahmed A.

    2016-01-01

    Highlights: • New temperature-based models for estimating solar radiation are investigated. • The models are validated against 20-years measured data of global solar radiation. • The new temperature-based model shows the best performance for coastal sites. • The new temperature-based model is more accurate than the sunshine-based models. • The new model is highly applicable with weather temperature forecast techniques. - Abstract: This study presents new ambient-temperature-based models for estimating global solar radiation as alternatives to the widely used sunshine-based models owing to the unavailability of sunshine data at all locations around the world. Seventeen new temperature-based models are established, validated and compared with other three models proposed in the literature (the Annandale, Allen and Goodin models) to estimate the monthly average daily global solar radiation on a horizontal surface. These models are developed using a 20-year measured dataset of global solar radiation for the case study location (Lat. 30°51′N and long. 29°34′E), and then, the general formulae of the newly suggested models are examined for ten different locations around Egypt. Moreover, the local formulae for the models are established and validated for two coastal locations where the general formulae give inaccurate predictions. Mostly common statistical errors are utilized to evaluate the performance of these models and identify the most accurate model. The obtained results show that the local formula for the most accurate new model provides good predictions for global solar radiation at different locations, especially at coastal sites. Moreover, the local and general formulas of the most accurate temperature-based model also perform better than the two most accurate sunshine-based models from the literature. The quick and accurate estimations of the global solar radiation using this approach can be employed in the design and evaluation of performance for

  10. Ocular Surface Temperature in Age-Related Macular Degeneration

    Directory of Open Access Journals (Sweden)

    Andrea Sodi

    2014-01-01

    Full Text Available Background. The aim of this study is to investigate the ocular thermographic profiles in age-related macular degeneration (AMD eyes and age-matched controls to detect possible hemodynamic abnormalities, which could be involved in the pathogenesis of the disease. Methods. 32 eyes with early AMD, 37 eyes with atrophic AMD, 30 eyes affected by untreated neovascular AMD, and 43 eyes with fibrotic AMD were included. The control group consisted of 44 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, diabetes mellitus, and a body temperature higher than 37.5°C. A total of 186 eyes without pupil dilation were investigated by infrared thermography (FLIR A320. The ocular surface temperature (OST of three ocular points was calculated by means of an image processing technique from the infrared images. Two-sample t-test and one-way analysis of variance (ANOVA test were used for statistical analyses. Results. ANOVA analyses showed no significant differences among AMD groups (P value >0.272. OST in AMD patients was significantly lower than in controls (P>0.05. Conclusions. Considering the possible relationship between ocular blood flow and OST, these findings might support the central role of ischemia in the pathogenesis of AMD.

  11. Rapid modification of urban land surface temperature during rainfall

    Science.gov (United States)

    Omidvar, H.; Bou-Zeid, E.; Song, J.; Yang, J.; Arwatz, G.; Wang, Z.; Hultmark, M.; Kaloush, K.

    2017-12-01

    We study the runoff dynamics and heat transfer over urban pavements during rainfall. A kinematic wave approach is combined with heat storage and transfer schemes to develop a model for impervious (with runoff) and pervious (without runoff) pavements. The resulting framework is a numerical prognostic model that can simulate the temperature fields in the subsurface and runoff layers to capture the rapid cooling of the surface, as well as the thermal pollution advected in the runoff. Extensive field measurements were then conducted over experimental pavements in Arizona to probe the physics and better represent the relevant processes in the model, and then to validate the model. The experimental data and the model results were in very good agreements, and their joint analysis elucidated the physics of the rapid heat transfer from the subsurface to the runoff layer. Finally, we apply the developed model to investigate how the various hydrological and thermal properties of the pavements, as well as ambient environmental conditions, modulate the surface and runoff thermal dynamics, what is the relative importance of each of them, and how we can apply the model mitigate the adverse impacts of urbanization.

  12. A spatiotemporal analysis of the relationship between near-surface air temperature and satellite land surface temperatures using 17 years of data from the ATSR series

    Science.gov (United States)

    Good, Elizabeth J.; Ghent, Darren J.; Bulgin, Claire E.; Remedios, John J.

    2017-09-01

    The relationship between satellite land surface temperature (LST) and ground-based observations of 2 m air temperature (T2m) is characterized in space and time using >17 years of data. The analysis uses a new monthly LST climate data record (CDR) based on the Along-Track Scanning Radiometer series, which has been produced within the European Space Agency GlobTemperature project (http://www.globtemperature.info/). Global LST-T2m differences are analyzed with respect to location, land cover, vegetation fraction, and elevation, all of which are found to be important influencing factors. LSTnight ( 10 P.M. local solar time, clear-sky only) is found to be closely coupled with minimum T2m (Tmin, all-sky) and the two temperatures generally consistent to within ±5°C (global median LSTnight-Tmin = 1.8°C, interquartile range = 3.8°C). The LSTday ( 10 A.M. local solar time, clear-sky only)-maximum T2m (Tmax, all-sky) variability is higher (global median LSTday-Tmax = -0.1°C, interquartile range = 8.1°C) because LST is strongly influenced by insolation and surface regime. Correlations for both temperature pairs are typically >0.9 outside of the tropics. The monthly global and regional anomaly time series of LST and T2m—which are completely independent data sets—compare remarkably well. The correlation between the data sets is 0.9 for the globe with 90% of the CDR anomalies falling within the T2m 95% confidence limits. The results presented in this study present a justification for increasing use of satellite LST data in climate and weather science, both as an independent variable, and to augment T2m data acquired at meteorological stations.

  13. Intermetallic-Based High-Temperature Materials

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.

    1999-04-25

    The intermetallic-based alloys for high-temperature applications are introduced. General characteristics of intermetallics are followed by identification of nickel and iron aluminides as the most practical alloys for commercial applications. An overview of the alloy compositions, melting processes, and mechanical properties for nickel and iron aluminizes are presented. The current applications and commercial producers of nickel and iron aluminizes are given. A brief description of the future prospects of intermetallic-based alloys is also given.

  14. A silicon-based electrical source for surface plasmon polaritons

    NARCIS (Netherlands)

    Walters, Robert J.; van Loon, Rob V.A.; Brunets, I.; Schmitz, Jurriaan; Polman, Albert

    2009-01-01

    This work demonstrates the fabrication of a silicon-based electrical source for surface plasmon polaritons (SPPs) at low temperatures using silicon nanocrystal doped alumina within a metal-insulator-metal (MIM) waveguide geometry. The fabrication method uses established microtechnology processes

  15. NOAA Climate Data Record (CDR) of Sea Surface Temperature - WHOI, Version 2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Ocean Surface Bundle (OSB) Climate Data Record (CDR) consist of three parts: sea surface temperature, near-surface atmospheric properties, and heat fluxes....

  16. SAFARI 2000 AVHRR-derived Land Surface Temperature Maps, Africa, 1995-2000

    Data.gov (United States)

    National Aeronautics and Space Administration — Land Surface Temperature (LST) is a key indicator of land surface states, and can provide information on surface-atmosphere heat and mass fluxes, vegetation water...

  17. SAFARI 2000 AVHRR-derived Land Surface Temperature Maps, Africa, 1995-2000

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Land Surface Temperature (LST) is a key indicator of land surface states, and can provide information on surface-atmosphere heat and mass fluxes,...

  18. Surface properties of magnetite in high temperature aqueous electrolyte solutions: A review.

    Science.gov (United States)

    Vidojkovic, Sonja M; Rakin, Marko P

    2017-07-01

    Deposits and scales formed on heat transfer surfaces in power plant water/steam circuits have a significant negative impact on plant reliability, availability and performance, causing tremendous economic consequences and subsequent increases in electricity cost. Consequently, the improvement of the understanding of deposition mechanisms on power generating surfaces is defined as a high priority in the power industry. The deposits consist principally of iron oxides, which are steel corrosion products and usually present in colloidal form. Magnetite (Fe 3 O 4 ) is the predominant and most abundant compound found in water/steam cycles of all types of power plants. The crucial factor that governs the deposition process and influences the deposition rate of magnetite is the electrostatic interaction between the metal wall surfaces and the suspended colloidal particles. However, there is scarcity of data on magnetite surface properties at elevated temperatures due to difficulties in their experimental measurement. In this paper a generalized overview of existing experimental data on surface characteristics of magnetite at high temperatures is presented with particular emphasis on possible application in the power industry. A thorough analysis of experimental techniques, mathematical models and results has been performed and directions for future investigations have been considered. The state-of-the-art assessment showed that for the characterization of magnetite/aqueous electrolyte solution interface at high temperatures acid-base potentiometric titrations and electrophoresis were the most beneficial and dependable techniques which yielded results up to 290 and 200°C, respectively. Mass titrations provided data on magnetite surface charge up to 320°C, however, this technique is highly sensitive to the minor concentrations of impurities present on the surface of particle. Generally, fairly good correlation between the isoelectric point (pH iep ) and point of zero charge

  19. A physically based analytical spatial air temperature and humidity model

    Science.gov (United States)

    Yang, Yang; Endreny, Theodore A.; Nowak, David J.

    2013-09-01

    Spatial variation of urban surface air temperature and humidity influences human thermal comfort, the settling rate of atmospheric pollutants, and plant physiology and growth. Given the lack of observations, we developed a Physically based Analytical Spatial Air Temperature and Humidity (PASATH) model. The PASATH model calculates spatial solar radiation and heat storage based on semiempirical functions and generates spatially distributed estimates based on inputs of topography, land cover, and the weather data measured at a reference site. The model assumes that for all grids under the same mesoscale climate, grid air temperature and humidity are modified by local variation in absorbed solar radiation and the partitioning of sensible and latent heat. The model uses a reference grid site for time series meteorological data and the air temperature and humidity of any other grid can be obtained by solving the heat flux network equations. PASATH was coupled with the USDA iTree-Hydro water balance model to obtain evapotranspiration terms and run from 20 to 29 August 2010 at a 360 m by 360 m grid scale and hourly time step across a 285 km2 watershed including the urban area of Syracuse, NY. PASATH predictions were tested at nine urban weather stations representing variability in urban topography and land cover. The PASATH model predictive efficiency R2 ranged from 0.81 to 0.99 for air temperature and 0.77 to 0.97 for dew point temperature. PASATH is expected to have broad applications on environmental and ecological models.

  20. Air and Ground Surface Temperature Relations in a Mountainous Basin, Wolf Creek, Yukon Territory

    Science.gov (United States)

    Roadhouse, Emily A.

    The links between climate and permafrost are well known, but the precise nature of the relationship between air and ground temperatures remains poorly understood, particularly in complex mountain environments. Although previous studies indicate that elevation and potential incoming solar radiation (PISR) are the two leading factors contributing to the existence of permafrost at a given location, additional factors may also contribute significantly to the existence of mountain permafrost, including vegetation cover, snow accumulation and the degree to which individual mountain landscapes are prone to air temperature inversions. Current mountain permafrost models consider only elevation and aspect, and have not been able to deal with inversion effects in a systematic fashion. This thesis explores the relationship between air and ground surface temperatures and the presence of surface-based inversions at 27 sites within the Wolf Creek basin and surrounding area between 2001 and 2006, as a first step in developing an improved permafrost distribution TTOP model. The TTOP model describes the relationship between the mean annual air temperature and the temperature at the top of permafrost in terms of the surface and thermal offsets (Smith and Riseborough, 2002). Key components of this model are n-factors which relate air and ground climate by establishing the ratio between air and surface freezing (winter) and thawing (summer) degree-days, thus summarizing the surface energy balance on a seasonal basis. Here we examine (1) surface offsets and (2) freezing and thawing n-factor variability at a number of sites through altitudinal treeline in the southern Yukon. Thawing n-factors (nt) measured at individual sites remained relatively constant from one year to the next and may be related to land cover. During the winter, the insulating effect of a thick snow cover results in higher surface temperatures, while thin snow cover results in low surface temperatures more closely

  1. Changes in Skin Surface Temperature during Muscular Endurance indicated Strain – An Explorative Study

    Directory of Open Access Journals (Sweden)

    Michael Fröhlich

    2014-07-01

    Full Text Available Introduction: Non-contact thermography enables the diagnosis of the distribution of skin surface temperature during athletic movement. Resistance exercise results in stress of required musculature, which is supposed to be measurable thermographically in terms of skin surface temperature change. Objective: This study aims to evaluate the application of thermography to analyze changes in skin temperature, representing specific muscle groups, during and after resistance exercise. Method: Thirteen male participants (age: 27.1 ± 4.9 years, height: 181.5 ± 5.7 cm, mass: 74.8 ± 7.4 kg completed the study. On 5 separate visits to the laboratory, participants performed one of 5 resistance exercise to target specific muscles (M. pectoralis major, M. rectus abdominis, M. trapezius, M. erector spinae, M. quadriceps femoris. The exercise protocol consisted of 3 sets of 20 repetitions, with 1 minute rest between exercise sets. The average skin surface temperature above the muscle groups used was thermographically determined using standard methods at 7 time points; pre-exercise, immediately following each exercise set, and post exercise (2, 3, and 6 minutes after the finale exercise set. The measurement areas were standardized using anatomic reference points. Results: From an inferential statistical point of view, no significant change in the average temperature caused by the applied resistance training was found for the individual muscle groups over time at the individual measurement times (all P>0.08. However, thermography showed a characteristic chronological temperature curve for the five body areas between measurement times, as well as a distinctive spatial temperature distribution over the measurement areas. Discussion: Based on the thermographic image data and the characteristic temperature curve, it is possible to identify the primarily used functional musculature after device-controlled resistance training. Therefore, thermography seems to be

  2. Surface-temperature trends and variability in the low-latitude North Atlantic since 1552

    KAUST Repository

    Saenger, Casey; Cohen, Anne L.; Oppo, Delia W.; Halley, Robert B.; Carilli, Jessica E.

    2009-01-01

    Sea surface temperature variability in the North Atlantic Ocean recorded since about 1850 has been ascribed to a natural multidecadal oscillation superimposed on a background warming trend1-6. It has been suggested that the multidecadal variability may be a persistent feature6-8, raising the possibility that the associated climate impacts may be predictable7,8. owever, our understanding of the multidecadal ocean variability before the instrumental record is based on interpretations of high-latitude terrestrial proxy records. Here we present an absolutely dated and annually resolved record of sea surface temperature from the Bahamas, based on a 440-year time series of coral growth rates. The reconstruction indicates that temperatures were as warm as today from about 1552 to 1570, then cooled by about 1° C from 1650 to 1730 before warming until the present. Our estimates of background variability suggest that much of the warming since 1900 was driven by anthropogenic forcing. Interdecadal variability with a period of 15-25 years is superimposed on most of the record, but multidecadal variability becomes significant only after 1730. We conclude that the multidecadal variability in sea surface temperatures in the low-latitude western Atlantic Ocean may not be persistent, potentially making accurate decadal climate forecasts more difficult to achieve. © 2009 Macmillan Publishers Limited. All rights reserved.

  3. Surface-temperature trends and variability in the low-latitude North Atlantic since 1552

    KAUST Repository

    Saenger, Casey

    2009-06-21

    Sea surface temperature variability in the North Atlantic Ocean recorded since about 1850 has been ascribed to a natural multidecadal oscillation superimposed on a background warming trend1-6. It has been suggested that the multidecadal variability may be a persistent feature6-8, raising the possibility that the associated climate impacts may be predictable7,8. owever, our understanding of the multidecadal ocean variability before the instrumental record is based on interpretations of high-latitude terrestrial proxy records. Here we present an absolutely dated and annually resolved record of sea surface temperature from the Bahamas, based on a 440-year time series of coral growth rates. The reconstruction indicates that temperatures were as warm as today from about 1552 to 1570, then cooled by about 1° C from 1650 to 1730 before warming until the present. Our estimates of background variability suggest that much of the warming since 1900 was driven by anthropogenic forcing. Interdecadal variability with a period of 15-25 years is superimposed on most of the record, but multidecadal variability becomes significant only after 1730. We conclude that the multidecadal variability in sea surface temperatures in the low-latitude western Atlantic Ocean may not be persistent, potentially making accurate decadal climate forecasts more difficult to achieve. © 2009 Macmillan Publishers Limited. All rights reserved.

  4. Temperature distribution and heat radiation of patterned surfaces at short wavelengths

    Science.gov (United States)

    Emig, Thorsten

    2017-05-01

    We analyze the equilibrium spatial distribution of surface temperatures of patterned surfaces. The surface is exposed to a constant external heat flux and has a fixed internal temperature that is coupled to the outside heat fluxes by finite heat conductivity across the surface. It is assumed that the temperatures are sufficiently high so that the thermal wavelength (a few microns at room temperature) is short compared to all geometric length scales of the surface patterns. Hence the radiosity method can be employed. A recursive multiple scattering method is developed that enables rapid convergence to equilibrium temperatures. While the temperature distributions show distinct dependence on the detailed surface shapes (cuboids and cylinder are studied), we demonstrate robust universal relations between the mean and the standard deviation of the temperature distributions and quantities that characterize overall geometric features of the surface shape.

  5. The Influence Study of Ultrasonic honing parameters to workpiece surface temperature

    Directory of Open Access Journals (Sweden)

    Zhang Xiaoqiang

    2016-01-01

    Full Text Available Ultrasonic vibration honing(UVH, a machine technology, has a lot of advantages. Lower grinding temperature is a significant character and is beneficial for both processing and workpiece surface. But the high temperature caused by big honing pressure becomes the main factor to produce workpiece heat damage in grinding zone. In various honing parameter combinations, the showing effect is different. Based on the thermodynamics classical theory, established the heat transfer equation for grinding zone, simplified the model and obtained the two-dimenssion temperature field expression for workpiece, then simulated the temperature changing trend in a variety of conditions. It is shown that themain temp is in a range of 700K to 1200K. In addition, the variation is huge for every parameter. The study provides a theoretical basis for deeply seeking reasonable machining parameter and obtaining better workpiece quality.

  6. Vicarious Calibration of sUAS Microbolometer Temperature Imagery for Estimation of Radiometric Land Surface Temperature

    Directory of Open Access Journals (Sweden)

    Alfonso Torres-Rua

    2017-06-01

    Full Text Available In recent years, the availability of lightweight microbolometer thermal cameras compatible with small unmanned aerial systems (sUAS has allowed their use in diverse scientific and management activities that require sub-meter pixel resolution. Nevertheless, as with sensors already used in temperature remote sensing (e.g., Landsat satellites, a radiance atmospheric correction is necessary to estimate land surface temperature. This is because atmospheric conditions at any sUAS flight elevation will have an adverse impact on the image accuracy, derived calculations, and study replicability using the microbolometer technology. This study presents a vicarious calibration methodology (sUAS-specific, time-specific, flight-specific, and sensor-specific for sUAS temperature imagery traceable back to NIST-standards and current atmospheric correction methods. For this methodology, a three-year data collection campaign with a sUAS called “AggieAir”, developed at Utah State University, was performed for vineyards near Lodi, California, for flights conducted at different times (early morning, Landsat overpass, and mid-afternoon” and seasonal conditions. From the results of this study, it was found that, despite the spectral response of microbolometer cameras (7.0 to 14.0 μm, it was possible to account for the effects of atmospheric and sUAS operational conditions, regardless of time and weather, to acquire accurate surface temperature data. In addition, it was found that the main atmospheric correction parameters (transmissivity and atmospheric radiance significantly varied over the course of a day. These parameters fluctuated the most in early morning and partially stabilized in Landsat overpass and in mid-afternoon times. In terms of accuracy, estimated atmospheric correction parameters presented adequate statistics (confidence bounds under ±0.1 for transmissivity and ±1.2 W/m2/sr/um for atmospheric radiance, with a range of RMSE below 1.0 W/m2/sr

  7. Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?

    Science.gov (United States)

    Van Wynsberge, Simon; Menkes, Christophe; Le Gendre, Romain; Passfield, Teuru; Andréfouët, Serge

    2017-12-01

    In remote coral reef environments, lagoon and reef in situ measurements of temperature are scarce. Sea Surface Temperature (SST) measured by satellite has been frequently used as a proxy of the lagoon temperature experienced by coral reef organisms (TL) especially during coral bleaching events. However, the link between SST and TL is poorly characterized. First, we compared the correlation between various SST series and TL from 2012 to 2016 in three atolls and one island in the Central South Pacific Ocean. Simple linear correlation between SST and TL ranged between 0.44 and 0.97 depending on lagoons, localities of sensors, and type of SST data. High-resolution-satellite-measurements of SST inside the lagoons did not outperform oceanic SST series, suggesting that SST products are not adapted for small lagoons. Second, we modelled the difference between oceanic SST and TL as a function of the drivers of lagoon water renewal and mixing, namely waves, tide, wind, and season. The multivariate models reduced significantly the bias between oceanic SST and TL. In atoll lagoons, and probably in other hydrodynamically semi-open systems, a correction taking into account these factors is necessary when SST are used to characterize organisms' thermal stress thresholds.

  8. Surface phase transitions in cu-based solid solutions

    Science.gov (United States)

    Zhevnenko, S. N.; Chernyshikhin, S. V.

    2017-11-01

    We have measured surface energy in two-component Cu-based systems in H2 + Ar gas atmosphere. The experiments on solid Cu [Ag] and Cu [Co] solutions show presence of phase transitions on the surfaces. Isotherms of the surface energy have singularities (the minimum in the case of copper solid solutions with silver and the maximum in the case of solid solutions with cobalt). In both cases, the surface phase transitions cause deficiency of surface miscibility: formation of a monolayer (multilayer) (Cu-Ag) or of nanoscale particles (Cu-Co). At the same time, according to the volume phase diagrams, the concentration and temperature of the surface phase transitions correspond to the solid solution within the volume. The method permits determining the rate of diffusional creep in addition to the surface energy. The temperature and concentration dependence of the solid solutions' viscosity coefficient supports the fact of the surface phase transitions and provides insights into the diffusion properties of the transforming surfaces.

  9. Surface temperature measurements on superconducting cavities in superfluid helium

    International Nuclear Information System (INIS)

    Fouaidy, T.; Junquera, T.; Caruette, A.

    1991-01-01

    Two thermometry systems have been developed: a scanning thermometer system routinely used for the 1.5 GHz monocell cavity studies and a fixed thermometer array used to investigate spatial surface resistance distribution on various SC removable endplates of a cylindrical TE011mode cavity. Thermometers used in these systems are thermally insulated from the surrounding HeII bath by an epoxy housing ('epoxy'thermometers). Accurate calibration of the fixed thermometers was conducted by using different test cells and the experimental results were compared to model calculations performed with a finite element computational code. Measured thermometer efficiency and linearity are in good agreement with numerical results. Some typical temperature maps of different Nb samples obtained with the TE011 array (40 epoxy thermometers) are discussed. On the basis of numerical modelling results, a new type of thermometer with an improved efficiency has been designed. The thermal insulation against Helium II has been drastically improved by placing the sensitive part of the thermometer in a small vacuum jacket ('vacuum' thermometers). Two main goals have been reached with the first prototypes: improved efficiency by a factor of 2.5 - 3, and a bath temperature dependence of the thermal response in good agreement with the expected Kapitza conductance behaviour. Fitting experimental results with numerical modelling data, allow us to estimate the Kapitza conductance. The obtained values are in good agreement with the previous results reported by several authors using a different measurement method. The 'vacuum' thermometers are currently used on the TE011 mode cavity with Nb and NbTiN plates and the first results are presented

  10. The approximate determination of the critical temperature of a liquid by measuring surface tension versus the temperature

    International Nuclear Information System (INIS)

    Maroto, J A; Nieves, F J de las; Quesada-Perez, M

    2004-01-01

    A classical experience in a physics student laboratory is to determine the surface tension of a liquid versus the temperature and to check the linear appearance of the obtained graph. In this work we show a simple method to estimate the critical temperature of three liquids by using experimental data of surface tension at different temperatures. By a logarithm fitting between surface tension and temperature, the critical temperature can be determined and compared with data from the literature. For two liquids (butanol and nitrobenzene) the comparison is acceptable but the differences are too high for the third liquid (water). By discussing the results it seems to be clear that the difference between the critical temperature of the liquid and the maximum temperature of the surface tension measurements is the determining factor in obtaining acceptable results. From this study it is possible to obtain more information on the liquid characteristics from surface tension measurements that are currently carried out in a student laboratory. Besides, in this paper it is shown how to select the most suitable liquids which provide both acceptable values for the critical temperature and measurements of the surface tension at moderate temperatures. The complementary use of numerical methods permits us to offer a complete experience for the students with a simple laboratory experiment which we recommend for physics students in advanced university courses

  11. Pristine carbon nanotubes based resistive temperature sensor

    International Nuclear Information System (INIS)

    Alam, Md Bayazeed; Saini, Sudhir Kumar; Sharma, Daya Shankar; Agarwal, Pankaj B.

    2016-01-01

    A good sensor must be highly sensitive, faster in response, of low cost cum easily producible, and highly reliable. Incorporation of nano-dimensional particles/ wires makes conventional sensors more effective in terms of fulfilling the above requirements. For example, Carbon Nanotubes (CNTs) are promising sensing element because of its large aspect ratio, unique electronic and thermal properties. In addition to their use for widely reported chemical sensing, it has also been explored for temperature sensing. This paper presents the fabrication of CNTs based temperature sensor, prepared on silicon substrate using low cost spray coating method, which is reliable and reproducible method to prepare uniform CNTs thin films on any substrate. Besides this, simple and inexpensive method of preparation of dispersion of single walled CNTs (SWNTs) in 1,2 dichlorobenzene by using probe type ultrasonicator for debundling the CNTs for improving sensor response were used. The electrical contacts over the dispersed SWNTs were taken using silver paste electrodes. Fabricated sensors clearly show immediate change in resistance as a response to change in temperature of SWNTs. The measured sensitivity (change in resistance with temperature) of the sensor was found ∼ 0.29%/°C in the 25°C to 60°C temperature range.

  12. Pristine carbon nanotubes based resistive temperature sensor

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Md Bayazeed, E-mail: bayazeed786@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Jamia Millia Islamia (New Delhi, India) (India); Saini, Sudhir Kumar, E-mail: sudhirsaini1310@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Sharma, Daya Shankar, E-mail: dssharmanit15@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Maulana Azad National Institute of Technology (MANIT, Bhopal, India) (India); Agarwal, Pankaj B., E-mail: agarwalbpankj@gmail.com [CSIR-Central Electronics Engineering Research Institute (CEERI, Pilani, India) (India); Academy for Scientific and Innovative Research (AcSIR, Delhi, India) (India)

    2016-04-13

    A good sensor must be highly sensitive, faster in response, of low cost cum easily producible, and highly reliable. Incorporation of nano-dimensional particles/ wires makes conventional sensors more effective in terms of fulfilling the above requirements. For example, Carbon Nanotubes (CNTs) are promising sensing element because of its large aspect ratio, unique electronic and thermal properties. In addition to their use for widely reported chemical sensing, it has also been explored for temperature sensing. This paper presents the fabrication of CNTs based temperature sensor, prepared on silicon substrate using low cost spray coating method, which is reliable and reproducible method to prepare uniform CNTs thin films on any substrate. Besides this, simple and inexpensive method of preparation of dispersion of single walled CNTs (SWNTs) in 1,2 dichlorobenzene by using probe type ultrasonicator for debundling the CNTs for improving sensor response were used. The electrical contacts over the dispersed SWNTs were taken using silver paste electrodes. Fabricated sensors clearly show immediate change in resistance as a response to change in temperature of SWNTs. The measured sensitivity (change in resistance with temperature) of the sensor was found ∼ 0.29%/°C in the 25°C to 60°C temperature range.

  13. Modeling seasonal surface temperature variations in secondary tropical dry forests

    Science.gov (United States)

    Cao, Sen; Sanchez-Azofeifa, Arturo

    2017-10-01

    Secondary tropical dry forests (TDFs) provide important ecosystem services such as carbon sequestration, biodiversity conservation, and nutrient cycle regulation. However, their biogeophysical processes at the canopy-atmosphere interface remain unknown, limiting our understanding of how this endangered ecosystem influences, and responds to the ongoing global warming. To facilitate future development of conservation policies, this study characterized the seasonal land surface temperature (LST) behavior of three successional stages (early, intermediate, and late) of a TDF, at the Santa Rosa National Park (SRNP), Costa Rica. A total of 38 Landsat-8 Thermal Infrared Sensor (TIRS) data and the Surface Reflectance (SR) product were utilized to model LST time series from July 2013 to July 2016 using a radiative transfer equation (RTE) algorithm. We further related the LST time series to seven vegetation indices which reflect different properties of TDFs, and soil moisture data obtained from a Wireless Sensor Network (WSN). Results showed that the LST in the dry season was 15-20 K higher than in the wet season at SRNP. We found that the early successional stages were about 6-8 K warmer than the intermediate successional stages and were 9-10 K warmer than the late successional stages in the middle of the dry season; meanwhile, a minimum LST difference (0-1 K) was observed at the end of the wet season. Leaf phenology and canopy architecture explained most LST variations in both dry and wet seasons. However, our analysis revealed that it is precipitation that ultimately determines the LST variations through both biogeochemical (leaf phenology) and biogeophysical processes (evapotranspiration) of the plants. Results of this study could help physiological modeling studies in secondary TDFs.

  14. An imaging system for quantitive surface temperature mapping using two-color thermographic phosphors

    Science.gov (United States)

    Buck, Gregory M.

    1988-01-01

    A technique for obtaining detailed quantitative temperature distributions on test models in hypersonic wind tunnels is presented. This technique is based on the ratio of blue to green (450, 520 nm) emission from an UV (365 nm) excited phosphor coating. Separately filtered images are recorded from a three-tube color camera, utilizing off-the-shelf front-end video optics to discriminate wavelengths. Two demonstration studies in a 31-inch Mach 10 tunnel are discussed. One study presents the windward surface temperature-time history for a transatmospheric vehicle, and the other illustrates nosetip heating on a spherically blunted slender cone.

  15. Mapping Surface Heat Fluxes by Assimilating SMAP Soil Moisture and GOES Land Surface Temperature Data

    Science.gov (United States)

    Lu, Yang; Steele-Dunne, Susan C.; Farhadi, Leila; van de Giesen, Nick

    2017-12-01

    Surface heat fluxes play a crucial role in the surface energy and water balance. In situ measurements are costly and difficult, and large-scale flux mapping is hindered by surface heterogeneity. Previous studies have demonstrated that surface heat fluxes can be estimated by assimilating land surface temperature (LST) and soil moisture to determine two key parameters: a neutral bulk heat transfer coefficient (CHN) and an evaporative fraction (EF). Here a methodology is proposed to estimate surface heat fluxes by assimilating Soil Moisture Active Passive (SMAP) soil moisture data and Geostationary Operational Environmental Satellite (GOES) LST data into a dual-source (DS) model using a hybrid particle assimilation strategy. SMAP soil moisture data are assimilated using a particle filter (PF), and GOES LST data are assimilated using an adaptive particle batch smoother (APBS) to account for the large gap in the spatial and temporal resolution. The methodology is implemented in an area in the U.S. Southern Great Plains. Assessment against in situ observations suggests that soil moisture and LST estimates are in better agreement with observations after assimilation. The RMSD for 30 min (daytime) flux estimates is reduced by 6.3% (8.7%) and 31.6% (37%) for H and LE on average. Comparison against a LST-only and a soil moisture-only assimilation case suggests that despite the coarse resolution, assimilating SMAP soil moisture data is not only beneficial but also crucial for successful and robust flux estimation, particularly when the uncertainties in the model estimates are large.

  16. Validation of the Suomi NPP VIIRS Ice Surface Temperature Environmental Data Record

    Directory of Open Access Journals (Sweden)

    Yinghui Liu

    2015-12-01

    Full Text Available Continuous monitoring of the surface temperature is critical to understanding and forecasting Arctic climate change; as surface temperature integrates changes in the surface energy budget. The sea-ice surface temperature (IST has been measured with optical and thermal infrared sensors for many years. With the IST Environmental Data Record (EDR available from the Visible Infrared Imaging Radiometer Suite (VIIRS onboard the Suomi National Polar-orbiting Partnership (NPP and future Joint Polar Satellite System (JPSS satellites; we can continue to monitor and investigate Arctic climate change. This work examines the quality of the VIIRS IST EDR. Validation is performed through comparisons with multiple datasets; including NASA IceBridge measurements; air temperature from Arctic drifting ice buoys; Moderate Resolution Imaging Spectroradiometer (MODIS IST; MODIS IST simultaneous nadir overpass (SNO; and surface air temperature from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR reanalysis. Results show biases of −0.34; −0.12; 0.16; −3.20; and −3.41 K compared to an aircraft-mounted downward-looking pyrometer; MODIS; MODIS SNO; drifting buoy; and NCEP/NCAR reanalysis; respectively; root-mean-square errors of 0.98; 1.02; 0.95; 4.89; and 6.94 K; and root-mean-square errors with the bias removed of 0.92; 1.01; 0.94; 3.70; and 6.04 K. Based on the IceBridge and MODIS results; the VIIRS IST uncertainty (RMSE meets or exceeds the JPSS system requirement of 1.0 K. The product can therefore be considered useful for meteorological and climatological applications.

  17. Temperature-dependent surface density of alkylthiol monolayers on gold nanocrystals

    Science.gov (United States)

    Liu, Xuepeng; Lu, Pin; Zhai, Hua; Wu, Yucheng

    2018-03-01

    Atomistic molecular dynamics (MD) simulations are performed to study the surface density of passivating monolayers of alkylthiol chains on gold nanocrystals at temperatures ranging from 1 to 800 K. The results show that the surface density of alkylthiol monolayer reaches a maximum value at near room temperature (200-300 K), while significantly decreases with increasing temperature in the higher temperature region (> 300 {{K}}), and slightly decreases with decreasing temperature at low temperature (< 200 {{K}}). We find that the temperature dependence of surface ligand density in the higher temperature region is attributed to the substantial ligand desorption induced by the thermal fluctuation, while that at low temperature results from the reduction in entropy caused by the change in the ordering of passivating monolayer. These results are expected helpful to understand the temperature-dependent surface coverage of gold nanocrystals.

  18. Hot roller embossing system equipped with a temperature margin-based controller

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seyoung, E-mail: seyoungkim@kimm.re.kr; Son, Youngsu; Lee, Sunghee; Ham, Sangyong; Kim, Byungin [Department of Robotics and Mechatronics, Korea Institute of Machinery and Materials (KIMM), Daejeon (Korea, Republic of)

    2014-08-15

    A temperature control system was proposed for hot roller embossing. The roll surface was heated using induction coils and cooled with a circulating chilled water system. The temperature of the roll surface was precisely controlled by a temperature margin-based control algorithm that we developed. Implementation of the control system reduced deviations in the roll surface temperature to less than ±2 °C. The tight temperature control and the ability to rapidly increase and decrease the roll temperature will allow optimum operating parameters to be developed quickly. The temperature margin-based controller could also be used to optimize the time course of electrical power and shorten the cooling time by choosing an appropriate temperature margin, possibly for limited power consumption. The chiller-equipped heating roll with the proposed control algorithm is expected to decrease the time needed to determine the optimal embossing process.

  19. Hot roller embossing system equipped with a temperature margin-based controller

    International Nuclear Information System (INIS)

    Kim, Seyoung; Son, Youngsu; Lee, Sunghee; Ham, Sangyong; Kim, Byungin

    2014-01-01

    A temperature control system was proposed for hot roller embossing. The roll surface was heated using induction coils and cooled with a circulating chilled water system. The temperature of the roll surface was precisely controlled by a temperature margin-based control algorithm that we developed. Implementation of the control system reduced deviations in the roll surface temperature to less than ±2 °C. The tight temperature control and the ability to rapidly increase and decrease the roll temperature will allow optimum operating parameters to be developed quickly. The temperature margin-based controller could also be used to optimize the time course of electrical power and shorten the cooling time by choosing an appropriate temperature margin, possibly for limited power consumption. The chiller-equipped heating roll with the proposed control algorithm is expected to decrease the time needed to determine the optimal embossing process

  20. Statistical analysis of global surface temperature and sea level using cointegration methods

    DEFF Research Database (Denmark)

    Schmidt, Torben; Johansen, Søren; Thejll, Peter

    2012-01-01

    Global sea levels are rising which is widely understood as a consequence of thermal expansion and melting of glaciers and land-based ice caps. Due to the lack of representation of ice-sheet dynamics in present-day physically-based climate models being unable to simulate observed sea level trends......, semi-empirical models have been applied as an alternative for projecting of future sea levels. There is in this, however, potential pitfalls due to the trending nature of the time series. We apply a statistical method called cointegration analysis to observed global sea level and land-ocean surface air...... temperature, capable of handling such peculiarities. We find a relationship between sea level and temperature and find that temperature causally depends on the sea level, which can be understood as a consequence of the large heat capacity of the ocean. We further find that the warming episode in the 1940s...

  1. Statistical analysis of global surface air temperature and sea level using cointegration methods

    DEFF Research Database (Denmark)

    Schmith, Torben; Johansen, Søren; Thejll, Peter

    Global sea levels are rising which is widely understood as a consequence of thermal expansion and melting of glaciers and land-based ice caps. Due to physically-based models being unable to simulate observed sea level trends, semi-empirical models have been applied as an alternative for projecting...... of future sea levels. There is in this, however, potential pitfalls due to the trending nature of the time series. We apply a statistical method called cointegration analysis to observed global sea level and surface air temperature, capable of handling such peculiarities. We find a relationship between sea...... level and temperature and find that temperature causally depends on the sea level, which can be understood as a consequence of the large heat capacity of the ocean. We further find that the warming episode in the 1940s is exceptional in the sense that sea level and warming deviates from the expected...

  2. Effects of temperature on surface modification of W exposed to He particles

    International Nuclear Information System (INIS)

    Li, C.; Greuner, H.; Yuan, Y.; Luo, G.N.; Böswirth, B.; Fu, B.Q.; Xu, H.Y.; Jia, Y.Z.; Liu, W.

    2014-01-01

    Highlights: • Blisters were observed on W surface under He beam heating at ∼950 °C. • He-induced blistering shows a clear grain orientation dependence. • An evolution to a coral-like structure was observed under loading at ∼2700 °C. • A texture with 〈0 0 1〉 parallel to the surface normal direction will be beneficial. - Abstract: The effect of combined heating and helium particle flux on annealed tungsten samples has been studied in the neutral beam facility GLADIS. He beams with power densities of 2.4 MW/m 2 and 9.5 MW/m 2 were used to adiabatically load the samples to peak surface temperatures from ∼950 °C (1223 K) to ∼2700 °C (2973 K). Changes in the surface morphology resulting from combined heat and the flux exposure were studied for He fluences up to 3 × 10 22 /m 2 . Typical structures for the sample loaded at ∼950 °C (1223 K) were blisters with a clear grain orientation dependence and the largest blisters formed on grains with 〈0 0 1〉 surface normal. However at higher temperatures, blistering was more easily suppressed for grains near this orientation because the growth of larger blister takes place more slowly. An evolution from a “porous structure” to a “coral-like structure” with increasing fluence was observed on the samples loaded at the highest temperature. Based on these results mechanisms for surface modification at different temperatures are discussed and a texture with 〈0 0 1〉 parallel to the normal direction of the grains is suggested to optimize the plasma facing material due to their stronger resistance to early stage blistering

  3. Decadal-scale teleconnection between South Atlantic SST and southeast Australia surface air temperature in austral summer

    Science.gov (United States)

    Xue, Jiaqing; Li, Jianping; Sun, Cheng; Zhao, Sen; Mao, Jiangyu; Dong, Di; Li, Yanjie; Feng, Juan

    2018-04-01

    Austral summer (December-February) surface air temperature over southeast Australia (SEA) is found to be remotely influenced by sea surface temperature (SST) in the South Atlantic at decadal time scales. In austral summer, warm SST anomalies in the southwest South Atlantic induce concurrent above-normal surface air temperature over SEA. This decadal-scale teleconnection occurs through the eastward propagating South Atlantic-Australia (SAA) wave train triggered by SST anomalies in the southwest South Atlantic. The excitation of the SAA wave train is verified by forcing experiments based on both linear barotropic and baroclinic models, propagation pathway and spatial scale of the observed SAA wave train are further explained by the Rossby wave ray tracing analysis in non-uniform basic flow. The SAA wave train forced by southwest South Atlantic warming is characterized by an anomalous anticyclone off the eastern coast of the Australia. Temperature diagnostic analyses based on the thermodynamic equation suggest anomalous northerly flows on western flank of this anticyclone can induce low-level warm advection anomaly over SEA, which thus lead to the warming of surface air temperature there. Finally, SST-forced atmospheric general circulation model ensemble experiments also demonstrate that SST forcing in the South Atlantic is associated with the SAA teleconnection wave train in austral summer, this wave train then modulate surface air temperature over SEA on decadal timescales. Hence, observations combined with numerical simulations consistently demonstrate the decadal-scale teleconnection between South Atlantic SST and summertime surface air temperature over SEA.

  4. Method of determination of temperature and heat resistance of the points on the integrated circuit crystal surface

    Directory of Open Access Journals (Sweden)

    Popov V. M.

    2011-12-01

    Full Text Available Method for visualization of integrated circuit (IC surface temperature by means of the liquid crystal film deposited from solution on its surface is proposed. The boundaries of local regions represent isotherms with corresponding phase transitions. On the base of isotherms positions and consumed by IC power thermal resistances between crystal and environment are determined.

  5. Estimating radiative feedbacks from stochastic fluctuations in surface temperature and energy imbalance

    Science.gov (United States)

    Proistosescu, C.; Donohoe, A.; Armour, K.; Roe, G.; Stuecker, M. F.; Bitz, C. M.

    2017-12-01

    Joint observations of global surface temperature and energy imbalance provide for a unique opportunity to empirically constrain radiative feedbacks. However, the satellite record of Earth's radiative imbalance is relatively short and dominated by stochastic fluctuations. Estimates of radiative feedbacks obtained by regressing energy imbalance against surface temperature depend strongly on sampling choices and on assumptions about whether the stochastic fluctuations are primarily forced by atmospheric or oceanic variability (e.g. Murphy and Forster 2010, Dessler 2011, Spencer and Braswell 2011, Forster 2016). We develop a framework around a stochastic energy balance model that allows us to parse the different contributions of atmospheric and oceanic forcing based on their differing impacts on the covariance structure - or lagged regression - of temperature and radiative imbalance. We validate the framework in a hierarchy of general circulation models: the impact of atmospheric forcing is examined in unforced control simulations of fixed sea-surface temperature and slab ocean model versions; the impact of oceanic forcing is examined in coupled simulations with prescribed ENSO variability. With the impact of atmospheric and oceanic forcing constrained, we are able to predict the relationship between temperature and radiative imbalance in a fully coupled control simulation, finding that both forcing sources are needed to explain the structure of the lagged-regression. We further model the dependence of feedback estimates on sampling interval by considering the effects of a finite equilibration time for the atmosphere, and issues of smoothing and aliasing. Finally, we develop a method to fit the stochastic model to the short timeseries of temperature and radiative imbalance by performing a Bayesian inference based on a modified version of the spectral Whittle likelihood. We are thus able to place realistic joint uncertainty estimates on both stochastic forcing and

  6. Downscaling Satellite Land Surface Temperatures in Urban Regions for Surface Energy Balance Study and Heat Index Development

    Science.gov (United States)

    Norouzi, H.; Bah, A.; Prakash, S.; Nouri, N.; Blake, R.

    2017-12-01

    A great percentage of the world's population reside in urban areas that are exposed to the threats of global and regional climate changes and associated extreme weather events. Among them, urban heat islands have significant health and economic impacts due to higher thermal gradients of impermeable surfaces in urban regions compared to their surrounding rural areas. Therefore, accurate characterization of the surface energy balance in urban regions are required to predict these extreme events. High spatial resolution Land surface temperature (LST) in the scale of street level in the cities can provide wealth of information to study surface energy balance and eventually providing a reliable heat index. In this study, we estimate high-resolution LST maps using combination of LandSat 8 and infrared based satellite products such as Moderate Resolution Imaging Spectroradiometer (MODIS) and newly launched Geostationary Operational Environmental Satellite-R Series (GOES-R). Landsat 8 provides higher spatial resolution (30 m) estimates of skin temperature every 16 days. However, MODIS and GOES-R have lower spatial resolution (1km and 4km respectively) with much higher temporal resolution. Several statistical downscaling methods were investigated to provide high spatiotemporal LST maps in urban regions. The results reveal that statistical methods such as Principal Component Analysis (PCA) can provide reliable estimations of LST downscaling with 2K accuracy. Other methods also were tried including aggregating (up-scaling) the high-resolution data to a coarse one to examine the limitations and to build the model. Additionally, we deployed flux towers over distinct materials such as concrete, asphalt, and rooftops in New York City to monitor the sensible and latent heat fluxes through eddy covariance method. To account for the incoming and outgoing radiation, a 4-component radiometer is used that can observe both incoming and outgoing longwave and shortwave radiation. This

  7. GHRSST Level 2P Atlantic Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-16 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset for the Atlantic Ocean and nearby regions based on multi-channel sea surface...

  8. GHRSST Level 2P Atlantic Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset for the Atlantic Ocean and nearby regions based on multi-channel sea surface...

  9. Forests tend to cool the land surface in the temperate zone: An analysis of the mechanisms controlling radiometric surface temperature change in managed temperate ecosystems

    Science.gov (United States)

    Stoy, P. C.; Katul, G. G.; Juang, J.; Siqueira, M. B.; Novick, K. A.; Essery, R.; Dore, S.; Kolb, T. E.; Montes-Helu, M. C.; Scott, R. L.

    2010-12-01

    Vegetation is an important control on the surface energy balance and thereby surface temperature. Boreal forests and arctic shrubs are thought to warm the land surface by absorbing more radiation than the vegetation they replace. The surface temperatures of tropical forests tend to be cooler than deforested landscapes due to enhanced evapotranspiration. The effects of reforestation on surface temperature change in the temperate zone is less-certain, but recent modeling efforts suggest forests have a global warming effect. We quantified the mechanisms driving radiometric surface changes following landcover changes using paired ecosystem case studies from the Ameriflux database with energy balance models of varying complexity. Results confirm previous findings that deciduous and coniferous forests in the southeastern U.S. are ca. 1 °C cooler than an adjacent field on an annual basis because aerodynamic/ecophysiological cooling of 2-3 °C outweighs an albedo-related warming of stand-replacing ponderosa pine fire was ca. 1 °C warmer than unburned stands because a 1.5 °C aerodynamic warming offset a slight surface cooling due to greater albedo and soil heat flux. An ecosystem dominated by mesquite shrub encroachment was nearly 2 °C warmer than a native grassland ecosystem as aerodynamic and albedo-related warming outweighed a small cooling effect due to changes in soil heat flux. The forested ecosystems in these case studies are documented to have higher carbon uptake than the non-forested systems. Results suggest that temperate forests tend to cool the land surface and suggest that previous model-based findings that forests warm the Earth’s surface globally should be reconsidered.Changes to radiometric surface temperature (K) following changes in vegetation using paired ecosystem case studies C4 grassland and shrub ecosystem surface temperatures were adjusted for differences in air temperature across sites.

  10. Optical switches based on surface plasmons

    International Nuclear Information System (INIS)

    Chen Cong; Wang Pei; Yuan Guanghui; Wang Xiaolei; Min Changjun; Deng Yan; Lu Yonghua; Ming Hai

    2008-01-01

    Great attention is being paid to surface plasmons (SPs) because of their potential applications in sensors, data storage and bio-photonics. Recently, more and more optical switches based on surface plasmon effects have been demonstrated either by simulation or experimentally. This article describes the principles, advantages and disadvantages of various types of optical switches based on SPs, in particular the all-optical switches. (authors)

  11. A non-invasive experimental approach for surface temperature measurements on semi-crystalline thermoplastics

    Science.gov (United States)

    Boztepe, Sinan; Gilblas, Remi; de Almeida, Olivier; Le Maoult, Yannick; Schmidt, Fabrice

    2017-10-01

    Most of the thermoforming processes of thermoplastic polymers and their composites are performed adopting a combined heating and forming stages at which a precursor is heated prior to the forming. This step is done in order to improve formability by softening the thermoplastic polymer. Due to low thermal conductivity and semi-transparency of polymers, infrared (IR) heating is widely used for thermoforming of such materials. Predictive radiation heat transfer models for temperature distributions are therefore critical for optimizations of thermoforming process. One of the key challenges is to build a predictive model including the physical background of radiation heat transfer phenomenon in semi-crystalline thermoplastics as their microcrystalline structure introduces an optically heterogeneous medium. In addition, the accuracy of a predictive model is required to be validated experimentally where IR thermography is one of the suitable methods for such a validation as it provides a non-invasive, full-field surface temperature measurement. Although IR cameras provide a non-invasive measurement, a key issue for obtaining a reliable measurement depends on the optical characteristics of a heated material and the operating spectral band of IR camera. It is desired that the surface of a material to be measured has a spectral band where the material behaves opaque and an employed IR camera operates in the corresponding band. In this study, the optical characteristics of the PO-based polymer are discussed and, an experimental approach is proposed in order to measure the surface temperature of the PO-based polymer via IR thermography. The preliminary analyses showed that IR thermographic measurements may not be simply performed on PO-based polymers and require a correction method as their semi-transparent medium introduce a challenge to obtain reliable surface temperature measurements.

  12. Current Options for Measuring the Surface Temperature of Dairy Cattle in a Stable Technology: Review

    Directory of Open Access Journals (Sweden)

    Kateřina Švejdová

    2016-05-01

    Full Text Available Regular measurement of the body surface temperature can help to assess the health status of animals. There are many technological possibilities of contactless temperature measurement of body surface. The important thing is to find the right part of the body whose temperature will point to the first possible symptoms and immediately react to the first signs of the disease. Disagreements about how to measure body surface temperature and accuracy of the method can occur when different measures are used. We review work showing possibilities of contactless surface temperature measurements using 1 thermography, 2 electronic transponders and 3 other possibilities of measuring the body surface temperature of dairy cattle. For example, when we scan the surface temperature with the thermal imager there can operate in individual animals confounding factors such as the nature or degree of muscular coat, which may significantly affect the results.

  13. Sea surface temperature variations in the western Mediterranean Sea over the last 20 kyr: A dual-organic proxy (U

    NARCIS (Netherlands)

    Rodrigo-Gámiz, M.; Martínez-Ruiz, F.; Rampen, S.W.; Schouten, S.; Sinninghe Damsté, J.S.

    2014-01-01

    A high-resolution sea surface temperature (SST) reconstruction of the western Mediterranean was accomplished using two independent, algae-based molecular organic proxies, i.e., the U-37(K) index based on long-chain unsaturated ketones and the novel long-chain diol index (LDI) based on the relative

  14. Temperature-Independent Fermi Surface in the Kondo Lattice YbRh_{2}Si_{2}

    Directory of Open Access Journals (Sweden)

    K. Kummer

    2015-03-01

    Full Text Available Strongly correlated electron systems are one of the central topics in contemporary solid-state physics. Prominent examples for such systems are Kondo lattices, i.e., intermetallic materials in which below a critical temperature, the Kondo temperature T_{K}, the magnetic moments become quenched and the effective masses of the conduction electrons approach the mass of a proton. In Ce- and Yb-based systems, this so-called heavy-fermion behavior is caused by interactions between the strongly localized 4f and itinerant electrons. A major and very controversially discussed issue in this context is how the localized electronic degree of freedom gets involved in the Fermi surface (FS upon increasing the interaction between both kinds of electrons or upon changing the temperature. In this paper, we show that the FS of a prototypic Kondo lattice, YbRh_{2}Si_{2}, does not change its size or shape in a wide temperature range extending from well below to far above the single-ion Kondo temperature T_{K}∼25  K of this system. This experimental observation, obtained by means of angle-resolved photoemission spectroscopy, is in remarkable contrast to the widely believed evolution from a large FS, including the 4f degrees of freedom, to a small FS, without the 4f’s, upon increasing temperature. Our results explicitly demonstrate a need to further advance in theoretical approaches based on the periodic Anderson model in order to elucidate the temperature dependence of Fermi surfaces in Kondo lattices.

  15. Optimal Estimation of Sea Surface Temperature from AMSR-E

    Directory of Open Access Journals (Sweden)

    Pia Nielsen-Englyst

    2018-02-01

    Full Text Available The Optimal Estimation (OE technique is developed within the European Space Agency Climate Change Initiative (ESA-CCI to retrieve subskin Sea Surface Temperature (SST from AQUA’s Advanced Microwave Scanning Radiometer—Earth Observing System (AMSR-E. A comprehensive matchup database with drifting buoy observations is used to develop and test the OE setup. It is shown that it is essential to update the first guess atmospheric and oceanic state variables and to perform several iterations to reach an optimal retrieval. The optimal number of iterations is typically three to four in the current setup. In addition, updating the forward model, using a multivariate regression model is shown to improve the capability of the forward model to reproduce the observations. The average sensitivity of the OE retrieval is 0.5 and shows a latitudinal dependency with smaller sensitivity for cold waters and larger sensitivity for warmer waters. The OE SSTs are evaluated against drifting buoy measurements during 2010. The results show an average difference of 0.02 K with a standard deviation of 0.47 K when considering the 64% matchups, where the simulated and observed brightness temperatures are most consistent. The corresponding mean uncertainty is estimated to 0.48 K including the in situ and sampling uncertainties. An independent validation against Argo observations from 2009 to 2011 shows an average difference of 0.01 K, a standard deviation of 0.50 K and a mean uncertainty of 0.47 K, when considering the best 62% of retrievals. The satellite versus in situ discrepancies are highest in the dynamic oceanic regions due to the large satellite footprint size and the associated sampling effects. Uncertainty estimates are available for all retrievals and have been validated to be accurate. They can thus be used to obtain very good retrieval results. In general, the results from the OE retrieval are very encouraging and demonstrate that passive microwave

  16. Using diurnal temperature signals to infer vertical groundwater-surface water exchange

    Science.gov (United States)

    Irvine, Dylan J.; Briggs, Martin A.; Lautz, Laura K.; Gordon, Ryan P.; McKenzie, Jeffrey M.; Cartwright, Ian

    2017-01-01

    Heat is a powerful tracer to quantify fluid exchange between surface water and groundwater. Temperature time series can be used to estimate pore water fluid flux, and techniques can be employed to extend these estimates to produce detailed plan-view flux maps. Key advantages of heat tracing include cost-effective sensors and ease of data collection and interpretation, without the need for expensive and time-consuming laboratory analyses or induced tracers. While the collection of temperature data in saturated sediments is relatively straightforward, several factors influence the reliability of flux estimates that are based on time series analysis (diurnal signals) of recorded temperatures. Sensor resolution and deployment are particularly important in obtaining robust flux estimates in upwelling conditions. Also, processing temperature time series data involves a sequence of complex steps, including filtering temperature signals, selection of appropriate thermal parameters, and selection of the optimal analytical solution for modeling. This review provides a synthesis of heat tracing using diurnal temperature oscillations, including details on optimal sensor selection and deployment, data processing, model parameterization, and an overview of computing tools available. Recent advances in diurnal temperature methods also provide the opportunity to determine local saturated thermal diffusivity, which can improve the accuracy of fluid flux modeling and sensor spacing, which is related to streambed scour and deposition. These parameters can also be used to determine the reliability of flux estimates from the use of heat as a tracer.

  17. Overstory removal and residue treatments affect soil surface, air, and soil temperature: implications for seedling survival

    Science.gov (United States)

    Roger D. Hungerford; Ronald E. Babbitt

    1987-01-01

    Potentially lethal ground surface temperatures were measured at three locations in the Northern Rocky Mountains but occurred more frequently under treatments with greater overstory removal. Observed maximum and minimum temperatures of exposed surfaces are directly related to the thermal properties of the surface materials. Survival of planted seedlings was consistent...

  18. Study of sea surface temperature distribution, in Angra dos Reis Nuclear Plant region - Mission Angra 01

    International Nuclear Information System (INIS)

    Stevenson, M.R.; Steffen, C.A.; Villagra, H.M.I.

    1982-03-01

    A study of spectral and temporal variations of sea surface temperature, using data obtained from level of satellite, aircraft and surface, with the purpose of evaluate and plot the small scale variations of sea surface temperature, due to thermal discharge from a nuclear the results of the first mission called Angra 1. (maps). (C.G.C.)

  19. Computation of the temperatures of a fluid flowing through a pipe from temperature measurements on the pipe's outer surface

    International Nuclear Information System (INIS)

    Sauer, G.

    1999-01-01

    A method for computing the temperatures of a fluid flowing through a pipe on the basis of temperatures recorded at the pipe's outer surface is presented. The heat conduction in the pipe wall is described by one-dimensional heat conduction elements. Heat transfer between fluid, pipe and surrounding is allowed for. The equation system resulting from the standard finite element discretization is reformulated to enable the computation of temperature events preceding the recorded temperature in time. It is shown that the method can be used to identify the actual fluid temperature from temperature data obtained only at the outer surface of the pipe. The temperatures in the pipe wall are computed with good accuracy even in the case of a severe thermal shock. (orig.) [de

  20. Nonlaser-based 3D surface imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shin-yee; Johnson, R.K.; Sherwood, R.J. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    3D surface imaging refers to methods that generate a 3D surface representation of objects of a scene under viewing. Laser-based 3D surface imaging systems are commonly used in manufacturing, robotics and biomedical research. Although laser-based systems provide satisfactory solutions for most applications, there are situations where non laser-based approaches are preferred. The issues that make alternative methods sometimes more attractive are: (1) real-time data capturing, (2) eye-safety, (3) portability, and (4) work distance. The focus of this presentation is on generating a 3D surface from multiple 2D projected images using CCD cameras, without a laser light source. Two methods are presented: stereo vision and depth-from-focus. Their applications are described.

  1. Predicting East African spring droughts using Pacific and Indian Ocean sea surface temperature indices

    Science.gov (United States)

    Funk, Christopher C.; Hoell, Andrew; Shukla, Shraddhanand; Blade, Ileana; Liebmann, Brant; Roberts, Jason B.; Robertson, Franklin R.

    2014-01-01

    In southern Ethiopia, Eastern Kenya, and southern Somalia poor boreal spring rains in 1999, 2000, 2004, 2007, 2008, 2009 and 2011 contributed to severe food insecurity and high levels of malnutrition. Predicting rainfall deficits in this region on seasonal and decadal time frames can help decision makers support disaster risk reduction while guiding climate-smart adaptation and agricultural development. Building on recent research that links more frequent droughts to a stronger Walker Circulation, warming in the Indo-Pacific warm pool, and an increased western Pacific sea surface temperature (SST) gradient, we explore the dominant modes of East African rainfall variability, links between these modes and sea surface temperatures, and a simple index-based monitoring-prediction system suitable for drought early warning.

  2. Temperature detectors on irradiated silicon base

    International Nuclear Information System (INIS)

    Karimov, M.; Dzhalelov, M.A.; Kurbanov, A.O.

    2005-01-01

    It is well known, that the most suitable for thermal resistors production is compensated silicon with impurities forming deep lying in forbidden zone, having big negative resistance temperature coefficients (RTC). In the capacity of initial materials for thermal resistors with negative RTC the n-type monocrystalline silicon with specific resistance ∼30 Ω·cm at 300 K is applied. Before the irradiation the phosphorus diffusion is realizing at temperature ∼1000 deg. C for 10 min. Irradiation is putting into practise by WWR-SM reactor fast neutrons within the range (7-10)·10 13 cm -2 . The produced resistors have nominal resistance range (8-20)·10 3 Ω·cm, coefficient of the thermal sensitivity B=4000-6000 deg. C., RTC α 300K =4-6.6 %/grad. It is shown, that offered method allows to obtain same type resistors characteristics on the base of neutron-irradiated material

  3. Data-Model Comparison of Pliocene Sea Surface Temperature

    Science.gov (United States)

    Dowsett, H. J.; Foley, K.; Robinson, M. M.; Bloemers, J. T.

    2013-12-01

    The mid-Piacenzian (late Pliocene) climate represents the most geologically recent interval of long-term average warmth and shares similarities with the climate projected for the end of the 21st century. As such, its fossil and sedimentary record represents a natural experiment from which we can gain insight into potential climate change impacts, enabling more informed policy decisions for mitigation and adaptation. We present the first systematic comparison of Pliocene sea surface temperatures (SST) between an ensemble of eight climate model simulations produced as part of PlioMIP (Pliocene Model Intercomparison Project) and the PRISM (Pliocene Research, Interpretation and Synoptic Mapping) Project mean annual SST field. Our results highlight key regional (mid- to high latitude North Atlantic and tropics) and dynamic (upwelling) situations where there is discord between reconstructed SST and the PlioMIP simulations. These differences can lead to improved strategies for both experimental design and temporal refinement of the palaeoenvironmental reconstruction. Scatter plot of multi-model-mean anomalies (squares) and PRISM3 data anomalies (large blue circles) by latitude. Vertical bars on data anomalies represent the variability of warm climate phase within the time-slab at each locality. Small colored circles represent individual model anomalies and show the spread of model estimates about the multi-model-mean. While not directly comparable in terms of the development of the means nor the meaning of variability, this plot provides a first order comparison of the anomalies. Encircled areas are a, PRISM low latitude sites outside of upwelling areas; b, North Atlantic coastal sequences and Mediterranean sites; c, large anomaly PRISM sites from the northern hemisphere. Numbers identify Ocean Drilling Program sites.

  4. Estimating Daily Global Evapotranspiration Using Penman–Monteith Equation and Remotely Sensed Land Surface Temperature

    Directory of Open Access Journals (Sweden)

    Roozbeh Raoufi

    2017-11-01

    Full Text Available Daily evapotranspiration (ET is modeled globally for the period 2000–2013 based on the Penman–Monteith equation with radiation and vapor pressures derived using remotely sensed Land Surface Temperature (LST from the MODerate resolution Imaging Spectroradiometer (MODIS on the Aqua and Terra satellites. The ET for a given land area is based on four surface conditions: wet/dry and vegetated/non-vegetated. For each, the ET resistance terms are based on land cover, leaf area index (LAI and literature values. The vegetated/non-vegetated fractions of the land surface are estimated using land cover, LAI, a simplified version of the Beer–Lambert law for describing light transition through vegetation and newly derived light extension coefficients for each MODIS land cover type. The wet/dry fractions of the land surface are nonlinear functions of LST derived humidity calibrated using in-situ ET measurements. Results are compared to in-situ measurements (average of the root mean squared errors and mean absolute errors for 39 sites are 0.81 mm day−1 and 0.59 mm day−1, respectively and the MODIS ET product, MOD16, (mean bias during 2001–2013 is −0.2 mm day−1. Although the mean global difference between MOD16 and ET estimates is only 0.2 mm day−1, local temperature derived vapor pressures are the likely contributor to differences, especially in energy and water limited regions. The intended application for the presented model is simulating ET based on long-term climate forecasts (e.g., using only minimum, maximum and mean daily or monthly temperatures.

  5. Application of Response Surface Methodology (RSM for Optimization of Operating Parameters and Performance Evaluation of Cooling Tower Cold Water Temperature

    Directory of Open Access Journals (Sweden)

    Ramkumar RAMAKRISHNAN

    2012-01-01

    Full Text Available The performance of a cooling tower was analyzed with various operating parameters tofind the minimum cold water temperature. In this study, optimization of operating parameters wasinvestigated. An experimental design was carried out based on central composite design (CCD withresponse surface methodology (RSM. This paper presents optimum operating parameters and theminimum cold water temperature using the RSM method. The RSM was used to evaluate the effectsof operating variables and their interaction towards the attainment of their optimum conditions.Based on the analysis, air flow, hot water temperature and packing height were high significanteffect on cold water temperature. The optimum operating parameters were predicted using the RSMmethod and confirmed through experiment.

  6. Molecular dynamics simulation of temperature effects on low energy near-surface cascades and surface damage in Cu

    Science.gov (United States)

    Zhu, Guo; Sun, Jiangping; Guo, Xiongxiong; Zou, Xixi; Zhang, Libin; Gan, Zhiyin

    2017-06-01

    The temperature effects on near-surface cascades and surface damage in Cu(0 0 1) surface under 500 eV argon ion bombardment were studied using molecular dynamics (MD) method. In present MD model, substrate system was fully relaxed for 1 ns and a read-restart scheme was introduced to save total computation time. The temperature dependence of damage production was calculated. The evolution of near-surface cascades and spatial distribution of adatoms at varying temperature were analyzed and compared. It was found that near-surface vacancies increased with temperature, which was mainly due to the fact that more atoms initially located in top two layers became adatoms with the decrease of surface binding energy. Moreover, with the increase of temperature, displacement cascades altered from channeling-like structure to branching structure, and the length of collision sequence decreased gradually, because a larger portion of energy of primary knock-on atom (PKA) was scattered out of focused chain. Furthermore, increasing temperature reduced the anisotropy of distribution of adatoms, which can be ascribed to that regular registry of surface lattice atoms was changed with the increase of thermal vibration amplitude of surface atoms.

  7. Molecular dynamics simulation of temperature effects on low energy near-surface cascades and surface damage in Cu

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Guo; Sun, Jiangping; Guo, Xiongxiong; Zou, Xixi; Zhang, Libin; Gan, Zhiyin, E-mail: ganzhiyin@126.com

    2017-06-15

    The temperature effects on near-surface cascades and surface damage in Cu(0 0 1) surface under 500 eV argon ion bombardment were studied using molecular dynamics (MD) method. In present MD model, substrate system was fully relaxed for 1 ns and a read-restart scheme was introduced to save total computation time. The temperature dependence of damage production was calculated. The evolution of near-surface cascades and spatial distribution of adatoms at varying temperature were analyzed and compared. It was found that near-surface vacancies increased with temperature, which was mainly due to the fact that more atoms initially located in top two layers became adatoms with the decrease of surface binding energy. Moreover, with the increase of temperature, displacement cascades altered from channeling-like structure to branching structure, and the length of collision sequence decreased gradually, because a larger portion of energy of primary knock-on atom (PKA) was scattered out of focused chain. Furthermore, increasing temperature reduced the anisotropy of distribution of adatoms, which can be ascribed to that regular registry of surface lattice atoms was changed with the increase of thermal vibration amplitude of surface atoms.

  8. Estimates of Eastern Equatorial Pacific Sea Surface Temperatures During the Pliocene From Carbonate 'Clumped Isotope' Thermometry

    Science.gov (United States)

    Thiagarajan, N.; Tripati, A.; Eiler, J.

    2007-12-01

    The early Pliocene (5 to 3 Ma) was an interval in Earth history that was globally warmer than the present; thus, study of the details of Pliocene climate can provide insights into the dynamics of warm climates. There are two competing models of the temperature structure of the tropical Pacific upper-ocean during the early Pliocene: the dynamical 'ocean thermostat' model [1,2] and the 'El Padre' (or permanent 'El Nino') model [3], each of which predict zonal temperature gradients and mean conditions in the Eastern Equatorial Pacific (EEP), and which differ markedly from one another in these predictions. The dynamical 'ocean thermostat' model predicts an increased temperature contrast between the Western Equatorial Pacific (WEP) and EEP, enhanced thermocline tilt and intensified upwelling under warmer conditions. In contrast, the 'El Padre' model postulates a collapse of the zonal temperature gradient, reduced thermocline tilt and a reduction in upwelling and/or warmer temperatures of upwelled waters. Existing reconstructions of tropical temperatures produce WEP sea surface temperatures which agree with each other, but yield very different results in the EEP [4,5]. We have reconstructed EEP sea surface temperatures at Ocean Drilling Program (ODP) Site 847 using a few samples spanning key intervals of the last 6 million years using carbonate clumped isotope thermometer [6,7,8]. This technique is based on the temperature dependence of the abundances of 13C-18O bonds in carbonate minerals. Initial measurements of planktonic foraminifera and coccoliths from ODP Site 847 indicate cool EEP sea surface temperatures, supporting models of Pliocene climate that have enhanced zonal temperature gradients, relative to modern. Analyses of Globigerinoides sacculifer (with sac) from sediments indicate calcification temperatures of 20.3°C ± 0.1°C and seawater δ18O values of -0.8‰ ± 0.1‰ from ~6.1 to 5.1 million years ago. Measurements of a mixed coccolith assemblage from the

  9. A Spatio-Temporal Analysis of the Relationship Between Near-Surface Air Temperature and Satellite Land Surface Temperatures Using 17 Years of Data from the ATSR Series

    Science.gov (United States)

    Ghent, D.; Good, E.; Bulgin, C.; Remedios, J. J.

    2017-12-01

    Surface temperatures (ST) over land have traditionally been measured at weather stations. There are many parts of the globe with very few stations, e.g. across much of Africa, leading to gaps in ST datasets, affecting our understanding of how ST is changing, and the impacts of extreme events. Satellites can provide global ST data but these observations represent how hot the land ST (LST; including the uppermost parts of e.g. trees, buildings) is to touch, whereas stations measure the air temperature just above the surface (T2m). Satellite LST data may only be available in cloud-free conditions and data records are frequently climate studies. In this study, the relationship between clear-sky satellite LST and all-sky T2m is characterised in space and time using >17 years of data. The analysis uses a new monthly LST climate data record (CDR) based on the Along-Track Scanning Radiometer (ATSR) series, which has been produced within the European Space Agency GlobTemperature project. The results demonstrate the dependency of the global LST-T2m differences on location, land cover, vegetation and elevation. LSTnight ( 10 pm local solar time) is found to be closely coupled with minimum T2m (Tmin) and the two temperatures generally consistent to within ±5 °C (global median LSTnight- Tmin= 1.8 °C, interquartile range = 3.8 °C). The LSTday ( 10 am local time)-maximum T2m (Tmax) variability is higher because LST is strongly influenced by insolation and surface regime (global median LSTday-Tmax= -0.1 °C, interquartile range = 8.1 °C). Correlations for both temperature pairs are typically >0.9 outside of the tropics. A crucial aspect of this study is a comparison between the monthly global anomaly time series of LST and CRUTEM4 T2m. The time series agree remarkably well, with a correlation of 0.9 and 90% of the CDR anomalies falling within the T2m 95% confidence limits (see figure). This analysis provides independent verification of the 1995-2012 T2m anomaly time series

  10. Urban Surface Temperature Reduction via the Urban Aerosol Direct Effect: A Remote Sensing and WRF Model Sensitivity Study

    Directory of Open Access Journals (Sweden)

    Menglin Jin

    2010-01-01

    Full Text Available The aerosol direct effect, namely, scattering and absorption of sunlight in the atmosphere, can lower surface temperature by reducing surface insolation. By combining National Aeronautics and Space Administration (NASA AERONET (AErosol RObotic NETwork observations in large cities with Weather Research and Forecasting (WRF model simulations, we find that the aerosol direct reduction of surface insolation ranges from 40–100Wm−2, depending on aerosol loading and land-atmosphere conditions. To elucidate the maximum possible effect, values are calculated using a radiative transfer model based on the top quartile of the multiyear instantaneous aerosol data observed by AERONET sites. As a result, surface skin temperature can be reduced by 1°C-2°C while 2-m surface air temperature reductions are generally on the order of 0.5°C–1°C.

  11. A process-level attribution of the annual cycle of surface temperature over the Maritime Continent

    Science.gov (United States)

    Li, Yana; Yang, Song; Deng, Yi; Hu, Xiaoming; Cai, Ming

    2017-12-01

    The annual cycle of the surface temperature over the Maritime Continent (MC) is characterized by two periods of rapid warming in March-April and September-October, respectively, and a period of rapid cooling in June-July. Based upon an analysis of energy balance within individual atmosphere-surface columns, the seasonal variations of surface temperature in the MC are partitioned into partial temperature changes associated with various radiative and non-radiative (dynamical) processes. The seasonal variations in direct solar forcing and surface latent heat flux show the largest positive contributions to the annual cycle of MC surface temperature while the changes in oceanic dynamics (including ocean heat content change) work against the temperature changes related to the annual cycle. The rapid warming in March-April is mainly a result of the changes in atmospheric quick processes and ocean-atmosphere coupling such as water vapor, surface latent heat flux, clouds, and atmospheric dynamics while the contributions from direct solar forcing and oceanic dynamics are negative. This feature is in contrast to that associated with the warming in September-October, which is driven mainly by the changes in solar forcing with a certain amount of contributions from water vapor and latent heat flux change. More contribution from atmospheric quick processes and ocean-atmosphere coupling in March-April coincides with the sudden northward movement of deep convection belt, while less contribution from these quick processes and coupling is accompanied with the convection belt slowly moving southward. The main contributors to the rapid cooling in June-July are the same as those to the rapid warming in March-April, and the cooling is also negatively contributed by direct solar forcing and oceanic dynamics. The changes in water vapor in all three periods contribute positively to the change in total temperature and they are associated with the change in the location of the center of

  12. Annual to Inter-Decadal Variability in Surface Air Temperature Along ...

    African Journals Online (AJOL)

    instrumental sea surface temperature (SST) and. East African rainfall ... accelerated rise in minimum temperatures. The objectives of the ... Altitude above sea level (m) Urban/Exposed. Tanga. 05.05°S ...... Environmental Report, South Florida.

  13. A quality-control procedure for surface temperature and surface layer inversion in the XBT data archive from the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Ghosh, A.K.; Pattanaik, J.; Ratnakaran, L.

    and surface layer temperature inversion. XBT surface temperatrues (XST) are compared with the surface temperature from simultaneous CTD observations from four cruises and the former were found to be erroneous in a number of stations. XSTs are usually corrected...

  14. Temporal and Spatial Variabilities of Japan Sea Surface Temperature and Atmospheric Forcings

    National Research Council Canada - National Science Library

    Chu, Peter C; Chen, Yuchun; Lu, Shihua

    1998-01-01

    ...) and surface air temperature (SAT) data during 1982-1994 and the National Center for Atmospheric Research surface wind stress curl data during 1982-1989 to investigate the Japan Sea SST temporal and spatial variabilities...

  15. Surface layer temperature inversion in the Bay of Bengal: Main characteristics and related mechanisms

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Suresh, I.; Gautham, S.; PrasannaKumar, S.; Lengaigne, M.; Rao, R.R.; Neetu, S.; Hegde, A.

    Surface layer temperature inversion (SLTI), a warm layer sandwiched between surface and subsurface colder waters, has been reported to frequently occur in conjunction with barrier layers in the Bay of Bengal (BoB), with potentially commensurable...

  16. On the sensitivity of Land Surface Temperature estimates in arid irrigated lands using MODTRAN

    KAUST Repository

    Rosas, Jorge; Houborg, Rasmus; McCabe, Matthew

    2015-01-01

    Land surface temperature (LST) derived from thermal infrared (TIR) satellite data has been reliably used as a remote indicator of evapotranspiration (ET) and surface moisture status. However, in order to retrieve the ET with an accuracy approaching

  17. Diurnal Cycles of High Resolution Land Surface Temperatures (LSTs) Determined from UAV Platforms Across a Range of Surface Types

    Science.gov (United States)

    McCabe, M.; Rosas Aguilar, J.; Parkes, S. D.; Aragon, B.

    2017-12-01

    Observation of land surface temperature (LST) has many practical uses, from studying boundary layer dynamics and land-atmosphere coupling, to investigating surface properties such as soil moisture status, heat stress and surface heat fluxes. Typically, LST is observed via satellite based sensors such as LandSat or via point measurements using IR radiometers. These measurements provide either good spatial coverage and resolution or good temporal coverage. However, neither are able to provide the needed spatial and temporal resolution for many of the research applications described above. Technological developments in the use of Unmanned Aerial Vehicles (UAVs), together with small thermal frame cameras, has enabled a capacity to overcome this spatiotemporal constraint. Utilising UAV platforms to collect LST measurements across diurnal cycles provides an opportunity to study how meteorological and surface properties vary in both space and time. Here we describe the collection of LST data from a multi-rotor UAV across a study domain that is observed multiple times throughout the day. Flights over crops of Rhodes grass and alfalfa, along with a bare desert surface, were repeated with between 8 and 11 surveys covering the period from early morning to sunset. Analysis of the collected thermal imagery shows that the constructed LST maps illustrate a strong diurnal cycle consistent with expected trends, but with considerable spatial and temporal variability observed within and between the different domains. These results offer new insights into the dynamics of land surface behavior in both dry and wet soil conditions and at spatiotemporal scales that are unable to be replicated using traditional satellite platforms.

  18. REGRESSION ANALYSIS OF SEA-SURFACE-TEMPERATURE PATTERNS FOR THE NORTH PACIFIC OCEAN.

    Science.gov (United States)

    SEA WATER, *SURFACE TEMPERATURE, *OCEANOGRAPHIC DATA, PACIFIC OCEAN, REGRESSION ANALYSIS , STATISTICAL ANALYSIS, UNDERWATER EQUIPMENT, DETECTION, UNDERWATER COMMUNICATIONS, DISTRIBUTION, THERMAL PROPERTIES, COMPUTERS.

  19. Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs

    DEFF Research Database (Denmark)

    Edmondson, Jill L; Stott, Iain; Davies, Zoe G

    2016-01-01

    months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees...... in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce...

  20. Estimating the Ocean Flow Field from Combined Sea Surface Temperature and Sea Surface Height Data

    Science.gov (United States)

    Stammer, Detlef; Lindstrom, Eric (Technical Monitor)

    2002-01-01

    This project was part of a previous grant at MIT that was moved over to the Scripps Institution of Oceanography (SIO) together with the principal investigator. The final report provided here is concerned only with the work performed at SIO since January 2000. The primary focus of this project was the study of the three-dimensional, absolute and time-evolving general circulation of the global ocean from a combined analysis of remotely sensed fields of sea surface temperature (SST) and sea surface height (SSH). The synthesis of those two fields was performed with other relevant physical data, and appropriate dynamical ocean models with emphasis on constraining ocean general circulation models by a combination of both SST and SSH data. The central goal of the project was to improve our understanding and modeling of the relationship between the SST and its variability to internal ocean dynamics, and the overlying atmosphere, and to explore the relative roles of air-sea fluxes and internal ocean dynamics in establishing anomalies in SST on annual and longer time scales. An understanding of those problems will feed into the general discussion on how SST anomalies vary with time and the extend to which they interact with the atmosphere.

  1. [The reaction of human surface and inside body temperature to extreme hypothermia].

    Science.gov (United States)

    Panchenko, O A; Onishchenko, V O; Liakh, Iu Ie

    2011-01-01

    The dynamics of changes in the parameters of the surface and core body temperature under the systematic impact of ultra-low temperature is described in this article. As a source of ultra-low temperature was used (Cryo Therapy Chamber) Zimmer Medizin Systeme firm Zimmer Electromedizin (Germany) (-110 degrees C). Surface and internal body temperature was measured by infrared thermometer immediately before visiting cryochamber and immediately after exiting. In the study conducted 47,464 measurements of body temperature. It was established that the internal temperature of the human body under the influence of ultra-low temperatures in the proposed mode of exposure remains constant, and the surface temperature of the body reduces by an average of 11.57 degrees C. The time frame stabilization of adaptive processes of thermoregulation under the systematic impact of ultra-low temperature was defined in the study.

  2. Recent Improvements in Retrieving Near-Surface Air Temperature and Humidity Using Microwave Remote Sensing

    Science.gov (United States)

    Roberts, J. Brent

    2010-01-01

    Detailed studies of the energy and water cycles require accurate estimation of the turbulent fluxes of moisture and heat across the atmosphere-ocean interface at regional to basin scale. Providing estimates of these latent and sensible heat fluxes over the global ocean necessitates the use of satellite or reanalysis-based estimates of near surface variables. Recent studies have shown that errors in the surface (10 meter)estimates of humidity and temperature are currently the largest sources of uncertainty in the production of turbulent fluxes from satellite observations. Therefore, emphasis has been placed on reducing the systematic errors in the retrieval of these parameters from microwave radiometers. This study discusses recent improvements in the retrieval of air temperature and humidity through improvements in the choice of algorithms (linear vs. nonlinear) and the choice of microwave sensors. Particular focus is placed on improvements using a neural network approach with a single sensor (Special Sensor Microwave/Imager) and the use of combined sensors from the NASA AQUA satellite platform. The latter algorithm utilizes the unique sampling available on AQUA from the Advanced Microwave Scanning Radiometer (AMSR-E) and the Advanced Microwave Sounding Unit (AMSU-A). Current estimates of uncertainty in the near-surface humidity and temperature from single and multi-sensor approaches are discussed and used to estimate errors in the turbulent fluxes.

  3. Influence of cyclic temperature changes on the microstructure of AISI 4140 after laser surface hardening

    International Nuclear Information System (INIS)

    Miokovic, T.; Schulze, V.; Voehringer, O.; Loehe, D.

    2007-01-01

    In recent years laser surface hardening using pulsed laser sources has become an increasingly established technology in engineering industry and has opened up wider possibilities for the application of selective surface hardening. However, the choice of the process parameters is generally based on experience rather than on their empirical influence on the resulting microstructure, and for hardening processes with cyclic temperature changes, almost no correlations between process parameters and hardening results are known. Therefore, some problems regarding the choice of the process parameters and their influence on the resulting microstructure still remain. In particular, there is a lack of data concerning the effect of cyclic temperature changes on hardening. To facilitate process optimization, this paper deals with a detailed characterization of the microstructures created in quenched and tempered AISI 4140 (German grade 42CrMo4) steel following a temperature-dependent laser surface hardening treatment. The structure properties were obtained from microhardness measurements, scanning electron microscopy investigations and X-ray diffraction analysis of retained austenite

  4. Influence of cyclic temperature changes on the microstructure of AISI 4140 after laser surface hardening

    Energy Technology Data Exchange (ETDEWEB)

    Miokovic, T. [Institute of Materials Science and Engineering I, University of Karlsruhe, 76131 Karlsruhe (Germany); Schulze, V. [Institute of Materials Science and Engineering I, University of Karlsruhe, 76131 Karlsruhe (Germany)]. E-mail: volker.schulze@mach.uni-karlsruhe.de; Voehringer, O. [Institute of Materials Science and Engineering I, University of Karlsruhe, 76131 Karlsruhe (Germany); Loehe, D. [Institute of Materials Science and Engineering I, University of Karlsruhe, 76131 Karlsruhe (Germany)

    2007-01-15

    In recent years laser surface hardening using pulsed laser sources has become an increasingly established technology in engineering industry and has opened up wider possibilities for the application of selective surface hardening. However, the choice of the process parameters is generally based on experience rather than on their empirical influence on the resulting microstructure, and for hardening processes with cyclic temperature changes, almost no correlations between process parameters and hardening results are known. Therefore, some problems regarding the choice of the process parameters and their influence on the resulting microstructure still remain. In particular, there is a lack of data concerning the effect of cyclic temperature changes on hardening. To facilitate process optimization, this paper deals with a detailed characterization of the microstructures created in quenched and tempered AISI 4140 (German grade 42CrMo4) steel following a temperature-dependent laser surface hardening treatment. The structure properties were obtained from microhardness measurements, scanning electron microscopy investigations and X-ray diffraction analysis of retained austenite.

  5. Low temperature gaseous surface hardening of stainless steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    The present contribution gives an overview of some of the technological aspects of low temperature thermochemical treatment of stainless steel. Examples of low temperature gaseous nitriding, carburising and nitrocarburising of stainless steel are presented and discussed. In particular......, the morphology, microstructure and characteristics of so-called expanite “layers” on stainless steel are addressed....

  6. Surface electrostatic waves in bounded high temperature superconductors

    International Nuclear Information System (INIS)

    Averkov, Yu.O.; Yakovenko, V.M.

    2008-01-01

    The dispersion relations of surface electrostatic waves propagating along the surface of semi bounded layered superconductor and in the slab of layered superconductor are theoretically investigated. An arbitrary inclination of superconductor layers to the interface of a vacuum - crystal and an arbitrary direction of propagation of surface waves in the plane of the interface are taking into account. The possibility of initiation of an absolute instability during the propagation of a non-relativistic plasma stream above the surface of the layered superconductor is shown

  7. Low Friction Surfaces for Low Temperature Applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar and other extraterrestrial environments put extreme demands on moving mechanical components. Gears must continue to function and surfaces must continue to...

  8. Reintroducing radiometric surface temperature into the Penman-Monteith formulation

    DEFF Research Database (Denmark)

    Mallick, Kaniska; Bøgh, Eva; Trebs, Ivonne

    2015-01-01

    ). It combines TR data with standard energy balance closure models for deriving a hybrid scheme that does not require parameterization of the surface (or stomatal) and aerodynamic conductances (gS and gB). STIC is formed by the simultaneous solution of four state equations and it uses TR as an additional data......E and H. The errors and uncertainties in both surface fluxes are comparable to the models that typically use land surface parameterizations for determining the unobserved components (gS and gB) of the surface energy balance models. However, the scheme is simpler, has the capabilities for generating...

  9. From Space to the Rocky Intertidal: Using NASA MODIS Sea Surface Temperature and NOAA Water Temperature to Predict Intertidal Logger Temperature

    Directory of Open Access Journals (Sweden)

    Jessica R. P. Sutton

    2017-02-01

    Full Text Available The development of satellite-derived datasets has greatly facilitated large-scale ecological studies, as in situ observations are spatially sparse and expensive undertakings. We tested the efficacy of using satellite sea surface temperature (SST collected by NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS and local water temperature collected from NOAA buoys and onshore stations to estimate submerged intertidal mussel logger temperatures. Daily SST and local water temperatures were compared to mussel logger temperatures at five study sites located along the Oregon coastline. We found that satellite-derived SSTs and local water temperatures were similarly correlated to the submerged mussel logger temperatures. This finding suggests that satellite-derived SSTs may be used in conjunction with local water temperatures to understand the temporal and spatial variation of mussel logger temperatures. While there are limitations to using satellite-derived temperature for ecological studies, including issues with temporal and spatial resolution, our results are promising.

  10. An updated global grid point surface air temperature anomaly data set: 1851--1990

    Energy Technology Data Exchange (ETDEWEB)

    Sepanski, R.J.; Boden, T.A.; Daniels, R.C.

    1991-10-01

    This document presents land-based monthly surface air temperature anomalies (departures from a 1951--1970 reference period mean) on a 5{degree} latitude by 10{degree} longitude global grid. Monthly surface air temperature anomalies (departures from a 1957--1975 reference period mean) for the Antarctic (grid points from 65{degree}S to 85{degree}S) are presented in a similar way as a separate data set. The data were derived primarily from the World Weather Records and the archives of the United Kingdom Meteorological Office. This long-term record of temperature anomalies may be used in studies addressing possible greenhouse-gas-induced climate changes. To date, the data have been employed in generating regional, hemispheric, and global time series for determining whether recent (i.e., post-1900) warming trends have taken place. This document also presents the monthly mean temperature records for the individual stations that were used to generate the set of gridded anomalies. The periods of record vary by station. Northern Hemisphere station data have been corrected for inhomogeneities, while Southern Hemisphere data are presented in uncorrected form. 14 refs., 11 figs., 10 tabs.

  11. Climate applications for NOAA 1/4° Daily Optimum Interpolation Sea Surface Temperature

    Science.gov (United States)

    Boyer, T.; Banzon, P. V. F.; Liu, G.; Saha, K.; Wilson, C.; Stachniewicz, J. S.

    2015-12-01

    Few sea surface temperature (SST) datasets from satellites have the long temporal span needed for climate studies. The NOAA Daily Optimum Interpolation Sea Surface Temperature (DOISST) on a 1/4° grid, produced at National Centers for Environmental Information, is based primarily on SSTs from the Advanced Very High Resolution Radiometer (AVHRR), available from 1981 to the present. AVHRR data can contain biases, particularly when aerosols are present. Over the three decade span, the largest departure of AVHRR SSTs from buoy temperatures occurred during the Mt Pinatubo and El Chichon eruptions. Therefore, in DOISST, AVHRR SSTs are bias-adjusted to match in situ SSTs prior to interpolation. This produces a consistent time series of complete SST fields that is suitable for modelling and investigating local climate phenomena like El Nino or the Pacific warm blob in a long term context. Because many biological processes and animal distributions are temperature dependent, there are also many ecological uses of DOISST (e.g., coral bleaching thermal stress, fish and marine mammal distributions), thereby providing insights into resource management in a changing ocean. The advantages and limitations of using DOISST for different applications will be discussed.

  12. Antarctic Temperature Extremes from MODIS Land Surface Temperatures: New Processing Methods Reveal Data Quality Puzzles

    Science.gov (United States)

    Grant, G.; Gallaher, D. W.

    2017-12-01

    New methods for processing massive remotely sensed datasets are used to evaluate Antarctic land surface temperature (LST) extremes. Data from the MODIS/Terra sensor (Collection 6) provides a twice-daily look at Antarctic LSTs over a 17 year period, at a higher spatiotemporal resolution than past studies. Using a data condensation process that creates databases of anomalous values, our processes create statistical images of Antarctic LSTs. In general, the results find few significant trends in extremes; however, they do reveal a puzzling picture of inconsistent cloud detection and possible systemic errors, perhaps due to viewing geometry. Cloud discrimination shows a distinct jump in clear-sky detections starting in 2011, and LSTs around the South Pole exhibit a circular cooling pattern, which may also be related to cloud contamination. Possible root causes are discussed. Ongoing investigations seek to determine whether the results are a natural phenomenon or, as seems likely, the results of sensor degradation or processing artefacts. If the unusual LST patterns or cloud detection discontinuities are natural, they point to new, interesting processes on the Antarctic continent. If the data artefacts are artificial, MODIS LST users should be alerted to the potential issues.

  13. Effect of design factors on surface temperature and wear in disk brakes

    Science.gov (United States)

    Santini, J. J.; Kennedy, F. E.; Ling, F. F.

    1976-01-01

    The temperatures, friction, wear and contact conditions that occur in high energy disk brakes are studied. Surface and near surface temperatures were monitored at various locations in a caliper disk brake during drag type testing, with friction coefficient and wear rates also being determined. The recorded transient temperature distributions in the friction pads and infrared photographs of the rotor disk surface both showed that contact at the friction surface was not uniform, with contact areas constantly shifting due to nonuniform thermal expansion and wear. The effect of external cooling and of design modifications on friction, wear and temperatures was also investigated. It was found that significant decreases in surface temperature and in wear rate can be achieved without a reduction in friction either by slotting the contacting face of the brake pad or by modifying the design of the pad support to improve pad compliance. Both design changes result in more uniform contact conditions on the friction surface.

  14. Climate change impact of livestock CH4 emission in India: Global temperature change potential (GTP) and surface temperature response.

    Science.gov (United States)

    Kumari, Shilpi; Hiloidhari, Moonmoon; Kumari, Nisha; Naik, S N; Dahiya, R P

    2018-01-01

    Two climate metrics, Global surface Temperature Change Potential (GTP) and the Absolute GTP (AGTP) are used for studying the global surface temperature impact of CH 4 emission from livestock in India. The impact on global surface temperature is estimated for 20 and 100 year time frames due to CH 4 emission. The results show that the CH 4 emission from livestock, worked out to 15.3 Tg in 2012. In terms of climate metrics GTP of livestock-related CH 4 emission in India in 2012 were 1030 Tg CO 2 e (GTP 20 ) and 62 Tg CO 2 e (GTP 100 ) at the 20 and 100 year time horizon, respectively. The study also illustrates that livestock-related CH 4 emissions in India can cause a surface temperature increase of up to 0.7mK and 0.036mK over the 20 and 100 year time periods, respectively. The surface temperature response to a year of Indian livestock emission peaks at 0.9mK in the year 2021 (9 years after the time of emission). The AGTP gives important information in terms of temperature change due to annual CH 4 emissions, which is useful when comparing policies that address multiple gases. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Impacts of land use and land cover on surface and air temperature in urban landscapes

    Science.gov (United States)

    Crum, S.; Jenerette, D.

    2015-12-01

    Accelerating urbanization affects regional climate as the result of changing land cover and land use (LCLU). Urban land cover composition may provide valuable insight into relationships among urbanization, air, and land-surface temperature (Ta and LST, respectively). Climate may alter these relationships, where hotter climates experience larger LULC effects. To address these hypotheses we examined links between Ta, LST, LCLU, and vegetation across an urban coastal to desert climate gradient in southern California, USA. Using surface temperature radiometers, continuously measuring LST on standardized asphalt, concrete, and turf grass surfaces across the climate gradient, we found a 7.2°C and 4.6°C temperature decrease from asphalt to vegetated cover in the coast and desert, respectively. There is 131% more temporal variation in asphalt than turf grass surfaces, but 37% less temporal variation in concrete than turf grass. For concrete and turf grass surfaces, temporal variation in temperature increased from coast to desert. Using ground-based thermal imagery, measuring LST for 24 h sequences over citrus orchard and industrial use locations, we found a 14.5°C temperature decrease from industrial to orchard land use types (38.4°C and 23.9°C, respectively). Additionally, industrial land use types have 209% more spatial variation than orchard (CV=0.20 and 0.09, respectively). Using a network of 300 Ta (iButton) sensors mounted in city street trees throughout the region and hyperspectral imagery data we found urban vegetation greenness, measured using the normalized difference vegetation index (NDVI), was negatively correlated to Ta at night across the climate gradient. Contrasting previous findings, the closest coupling between NDVI and Ta is at the coast from 0000 h to 0800 h (highest r2 = 0.6, P urbanized regions of southern California, USA decrease Ta and LST and spatial variation in LST, while built surfaces and land uses have the opposite effect. Furthermore

  16. Impact of Vegetation Cover Fraction Parameterization schemes on Land Surface Temperature Simulation in the Tibetan Plateau

    Science.gov (United States)

    Lv, M.; Li, C.; Lu, H.; Yang, K.; Chen, Y.

    2017-12-01

    The parameterization of vegetation cover fraction (VCF) is an important component of land surface models. This paper investigates the impacts of three VCF parameterization schemes on land surface temperature (LST) simulation by the Common Land Model (CoLM) in the Tibetan Plateau (TP). The first scheme is a simple land cover (LC) based method; the second one is based on remote sensing observation (hereafter named as RNVCF) , in which multi-year climatology VCFs is derived from Moderate-resolution Imaging Spectroradiometer (MODIS) NDVI (Normalized Difference Vegetation Index); the third VCF parameterization scheme derives VCF from the LAI simulated by LSM and clump index at every model time step (hereafter named as SMVCF). Simulated land surface temperature(LST) and soil temperature by CoLM with three VCF parameterization schemes were evaluated by using satellite LST observation and in situ soil temperature observation, respectively, during the period of 2010 to 2013. The comparison against MODIS Aqua LST indicates that (1) CTL produces large biases for both four seasons in early afternoon (about 13:30, local solar time), while the mean bias in spring reach to 12.14K; (2) RNVCF and SMVCF reduce the mean bias significantly, especially in spring as such reduce is about 6.5K. Surface soil temperature observed at 5 cm depth from three soil moisture and temperature monitoring networks is also employed to assess the skill of three VCF schemes. The three networks, crossing TP from West to East, have different climate and vegetation conditions. In the Ngari network, located in the Western TP with an arid climate, there are not obvious differences among three schemes. In Naqu network, located in central TP with a semi-arid climate condition, CTL shows a severe overestimates (12.1 K), but such overestimations can be reduced by 79% by RNVCF and 87% by SMVCF. In the third humid network (Maqu in eastern TP), CoLM performs similar to Naqu. However, at both Naqu and Maqu networks

  17. Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel.

    Science.gov (United States)

    Zhang, Pengfei; Huawei, Chen; Liu, Guang; Zhang, Liwen; Zhang, Deyuan

    2018-03-29

    Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A typical anti-wetting superhydrophobic surface easily fails when exposed to a high-temperature liquid. Recently, Nepenthes-inspired slippery surfaces demonstrated a new way to solve the adhesion problem. A lubricant layer on the slippery surface can act as a barrier between the repelled materials and the surface structure. However, the slippery surfaces in previous studies rarely showed high-temperature resistance. Here, we describe a protocol for the preparation of slippery surfaces with high-temperature resistance. A photolithography-assisted method was used to fabricate pillar structures on stainless steel. By functionalizing the surface with saline, a slippery surface was prepared by adding silicone oil. The prepared slippery surface maintained the anti-wetting property for water, even when the surface was heated to 300 °C. Also, the slippery surface exhibited great anti-adhesion effects on soft tissues at high temperatures. This type of slippery surface on stainless steel has applications in medical devices, mechanical equipment, etc.

  18. Inverse estimation for temperatures of outer surface and geometry of inner surface of furnace with two layer walls

    International Nuclear Information System (INIS)

    Chen, C.-K.; Su, C.-R.

    2008-01-01

    This study provides an inverse analysis to estimate the boundary thermal behavior of a furnace with two layer walls. The unknown temperature distribution of the outer surface and the geometry of the inner surface were estimated from the temperatures of a small number of measured points within the furnace wall. The present approach rearranged the matrix forms of the governing differential equations and then combined the reversed matrix method, the linear least squares error method and the concept of virtual area to determine the unknown boundary conditions of the furnace system. The dimensionless temperature data obtained from the direct problem were used to simulate the temperature measurements. The influence of temperature measurement errors upon the precision of the estimated results was also investigated. The advantage of this approach is that the unknown condition can be directly solved by only one calculation process without initially guessed temperatures, and the iteration process of the traditional method can be avoided in the analysis of the heat transfer. Therefore, the calculation in this work is more rapid and exact than the traditional method. The result showed that the estimation error of the geometry increased with increasing distance between measured points and inner surface and in preset error, and with decreasing number of measured points. However, the geometry of the furnace inner surface could be successfully estimated by only the temperatures of a small number of measured points within and near the outer surface under reasonable preset error

  19. Distributed Temperature Sensing - a Useful Tool for Investigation of Surface Water - Groundwater Interaction

    Science.gov (United States)

    Vogt, T.; Hahn-Woernle, L.; Sunarjo, B.; Thum, T.; Schneider, P.; Schirmer, M.; Cirpka, O. A.

    2009-04-01

    In recent years, the transition zone between surface water bodies and groundwater, known as the hyporheic zone, has been identified as crucial for the ecological status of the open-water body and the quality of groundwater. The hyporheic exchange processes vary both in time and space. For the assessment of water quality of both water bodies reliable models and measurements of the exchange rates and their variability are needed. A wide range of methods and technologies exist to estimate water fluxes between surface water and groundwater. Due to recent developments in sensor techniques and data logging work on heat as a tracer in hydrological systems advances, especially with focus on surface water - groundwater interactions. Here, we evaluate the use of Distributed Temperature Sensing (DTS) for the qualitative and quantitative investigation of groundwater discharge into and groundwater recharge from a river. DTS is based on the temperature dependence of Raman scattering. Light from a laser pulse is scattered along an optical fiber of up to several km length, which is the sensor of the DTS system. By sampling the the back-scattered light with high temporal resolution, the temperature along the fiber can be measured with high accuracy (0.1 K) and high spatial resolution (1 m). We used DTS at a test side at River Thur in North-East Switzerland. Here, the river is loosing and the aquifer is drained by two side-channels, enabling us to test DTS for both, groundwater recharge from the river and groundwater discharge into the side-channels. For estimation of seepage rates, we measured highly resolved vertical temperature profiles in the river bed. For this application, we wrapped an optical fiber around a piezometer tube and measured the temperature distribution along the fiber. Due to the wrapping, we obtained a vertical resolution of approximately 5 mm. We analyzed the temperature time series by means of Dynamic Harmonic Regression as presented by Keery et al. (2007

  20. Surface layer temperature inversion in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Gopalakrishna, V.V.; Muraleedharan, P.M.; Reddy, G.V.; Araligidad, N.

    Hydrographic and XBT data archived in the Indian Oceanographic Data Centre (IODC) are used to understand the process of temperature inversions occurring in the Bay of Bengal. The following aspects of the inversions are addressed: i) annual...

  1. Time-Resolved Surface Temperature Measurement for Pulsed Ablative Thrusters

    National Research Council Canada - National Science Library

    Antonsen, Erik

    2003-01-01

    .... The diagnostic draws on heritage from the experimental dynamic crack propagation community which has used photovoltaic infrared detectors to measure temperature rise in materials in the process of fracture...

  2. GHRSST Level 2P Global Skin Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the MetOp-A satellite produced by EUMETSAT (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global 1 km Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated...

  3. GHRSST Level 2P Global skin Sea Surface Temperature from the Infrared Atmospheric Sounding Interferometer (IASI) on the Metop-B satellite (GDS V2) produced by OSI SAF (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in real-time...

  4. GHRSST Level 2P Global skin Sea Surface Temperature from the Infrared Atmospheric Sounding Interferometer (IASI) on the Metop-A satellite (GDS V2) produced by OSI SAF (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global 1 km Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated...

  5. GHRSST Level 2P Global 1m Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-18 satellite produced by NAVO (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  6. GHRSST Level 2P Global 1m Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the MetOp-B satellite produced by NAVO (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  7. GHRSST Level 2P sub-skin Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on Metop satellites (currently Metop-A) (GDS V2) produced by OSI SAF (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global 1 km Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated...

  8. GHRSST Level 2P Regional 1m Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-19 satellite produced by NAVO (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  9. GHRSST Level 2P sub-skin Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on Metop satellites (currently Metop-B) (GDS V2) produced by OSI SAF (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global 1 km Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated...

  10. GHRSST Level 2P Global 1m Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the MetOp-A satellite produced by NAVO (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  11. GHRSST Level 2P Global 1m Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-19 satellite produced by NAVO (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  12. Temperature-Responsive Anisotropic Slippery Surface for Smart Control of the Droplet Motion.

    Science.gov (United States)

    Wang, By Lili; Heng, Liping; Jiang, Lei

    2018-02-28

    Development of stimulus-responsive anisotropic slippery surfaces is important because of the high demand for such materials in the field of liquid directional-driven systems. However, current studies in the field of slippery surfaces are mainly conducted to prepare isotropic slippery surfaces. Although we have developed electric-responsive anisotropic slippery surfaces that enable smart control of the droplet motion, there remain challenges for designing temperature-responsive anisotropic slippery surfaces to control the liquid droplet motion on the surface and in the tube. In this work, temperature-responsive anisotropic slippery surfaces have been prepared by using paraffin, a thermo-responsive phase-transition material, as a lubricating fluid and directional porous polystyrene (PS) films as the substrate. The smart regulation of the droplet motion of several liquids on this surface was accomplished by tuning the substrate temperature. The uniqueness of this surface lies in the use of an anisotropic structure and temperature-responsive lubricating fluids to achieve temperature-driven smart control of the anisotropic motion of the droplets. Furthermore, this surface was used to design temperature-driven anisotropic microreactors and to manipulate liquid transfer in tubes. This work advances the understanding of the principles underlying anisotropic slippery surfaces and provides a promising material for applications in the biochip and microreactor system.

  13. Temperature increases on the external root surface during ...

    African Journals Online (AJOL)

    2015-02-25

    Feb 25, 2015 ... surface caused bone resorption and tooth ankyloses.[9] The .... thickness is important because it acts as a protective coating against thermal damage. .... heat stress proteins by human periodontal ligament cells. J Oral Pathol.

  14. Lake Chad Total Surface Water Area as Derived from Land Surface Temperature and Radar Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Frederick Policelli

    2018-02-01

    Full Text Available Lake Chad, located in the middle of the African Sahel belt, underwent dramatic decreases in the 1970s and 1980s leaving less than ten percent of its 1960s surface water extent as open water. In this paper, we present an extended record (dry seasons 1988–2016 of the total surface water area of the lake (including both open water and flooded vegetation derived using Land Surface Temperature (LST data (dry seasons 2000–2016 from the NASA Terra MODIS sensor and EUMETSAT Meteosat-based LST measurements (dry seasons 1988–2001 from an earlier study. We also examine the total surface water area for Lake Chad using radar data (dry seasons 2015–2016 from the ESA Sentinel-1a mission. For the limited number of radar data sets available to us (18 data sets, we find on average a close match between the estimates from these data and the corresponding estimates from LST, though we find spatial differences in the estimates using the two types of data. We use these spatial differences to adjust the record (dry seasons 2000–2016 from MODIS LST. Then we use the adjusted record to remove the bias of the existing LST record (dry seasons 1988–2001 derived from Meteosat measurements and combine the two records. From this composite, extended record, we plot the total surface water area of the lake for the dry seasons of 1988–1989 through 2016–2017. We find for the dry seasons of 1988–1989 to 2016–2017 that the maximum total surface water area of the lake was approximately 16,800 sq. km (February and May, 2000, the minimum total surface water area of the lake was approximately 6400 sq. km (November, 1990, and the average was approximately 12,700 sq. km. Further, we find the total surface water area of the lake to be highly variable during this period, with an average rate of increase of approximately 143 km2 per year.

  15. Identifying anthropogenic anomalies in air, surface and groundwater temperatures in Germany.

    Science.gov (United States)

    Benz, Susanne A; Bayer, Peter; Blum, Philipp

    2017-04-15

    Human activity directly influences ambient air, surface and groundwater temperatures. The most prominent phenomenon is the urban heat island effect, which has been investigated particularly in large and densely populated cities. This study explores the anthropogenic impact on the thermal regime not only in selected urban areas, but on a countrywide scale for mean annual temperature datasets in Germany in three different compartments: measured surface air temperature, measured groundwater temperature, and satellite-derived land surface temperature. Taking nighttime lights as an indicator of rural areas, the anthropogenic heat intensity is introduced. It is applicable to each data set and provides the difference between measured local temperature and median rural background temperature. This concept is analogous to the well-established urban heat island intensity, but applicable to each measurement point or pixel of a large, even global, study area. For all three analyzed temperature datasets, anthropogenic heat intensity grows with increasing nighttime lights and declines with increasing vegetation, whereas population density has only minor effects. While surface anthropogenic heat intensity cannot be linked to specific land cover types in the studied resolution (1km×1km) and classification system, both air and groundwater show increased heat intensities for artificial surfaces. Overall, groundwater temperature appears most vulnerable to human activity, albeit the different compartments are partially influenced through unrelated processes; unlike land surface temperature and surface air temperature, groundwater temperatures are elevated in cultivated areas as well. At the surface of Germany, the highest anthropogenic heat intensity with 4.5K is found at an open-pit lignite mine near Jülich, followed by three large cities (Munich, Düsseldorf and Nuremberg) with annual mean anthropogenic heat intensities >4K. Overall, surface anthropogenic heat intensities >0K and

  16. Temperature dependence of immunoreactions using shear horizontal surface acoustic wave immunosensors

    Science.gov (United States)

    Kogai, Takashi; Yatsuda, Hiromi; Kondoh, Jun

    2017-07-01

    In this paper, the temperature dependence of immunoreactions, which are antibody-antigen reactions, on a shear horizontal surface acoustic wave (SH-SAW) immunosensor is described. The immunosensor is based on a reflection-type delay line on a 36° Y-cut 90° X-propagation quartz substrate, where the delay line is composed of a floating electrode unidirectional transducer (FEUDT), a grating reflector, and a sensing area between them. In order to evaluate the temperature dependence of immunoreactions, human serum albumin (HSA) antigen-antibody reactions are investigated. The SH-SAW immunosensor chip is placed in a thermostatic chamber and the changes in the SH-SAW velocity resulting from the immunoreactions are measured at different temperatures. As a result, it is observed that the HSA immunoreactions are influenced by the ambient temperature and that higher temperatures provide more active reactions. In order to analyze the immunoreactions, an analytical approach using an exponential fitting method for changes in SH-SAW velocity is employed.

  17. Developing first time-series of land surface temperature from AATSR with uncertainty estimates

    Science.gov (United States)

    Ghent, Darren; Remedios, John

    2013-04-01

    Land surface temperature (LST) is the radiative skin temperature of the land, and is one of the key parameters in the physics of land-surface processes on regional and global scales. Earth Observation satellites provide the opportunity to obtain global coverage of LST approximately every 3 days or less. One such source of satellite retrieved LST has been the Advanced Along-Track Scanning Radiometer (AATSR); with LST retrieval being implemented in the AATSR Instrument Processing Facility in March 2004. Here we present first regional and global time-series of LST data from AATSR with estimates of uncertainty. Mean changes in temperature over the last decade will be discussed along with regional patterns. Although time-series across all three ATSR missions have previously been constructed (Kogler et al., 2012), the use of low resolution auxiliary data in the retrieval algorithm and non-optimal cloud masking resulted in time-series artefacts. As such, considerable ESA supported development has been carried out on the AATSR data to address these concerns. This includes the integration of high resolution auxiliary data into the retrieval algorithm and subsequent generation of coefficients and tuning parameters, plus the development of an improved cloud mask based on the simulation of clear sky conditions from radiance transfer modelling (Ghent et al., in prep.). Any inference on this LST record is though of limited value without the accompaniment of an uncertainty estimate; wherein the Joint Committee for Guides in Metrology quote an uncertainty as "a parameter associated with the result of a measurement that characterizes the dispersion of the values that could reasonably be attributed to the measurand that is the value of the particular quantity to be measured". Furthermore, pixel level uncertainty fields are a mandatory requirement in the on-going preparation of the LST product for the upcoming Sea and Land Surface Temperature (SLSTR) instrument on-board Sentinel-3

  18. Experimental and Theoretical Analysis of Headlight Surface Temperature in an Infrared Heated Stress Relieving Oven

    Directory of Open Access Journals (Sweden)

    Mustafa MUTLU

    2016-04-01

    Full Text Available In this study, the IR heated stress relieve oven was experimentally and theoretically examined. In experimental measurements, temperature was measured on headlight surface, placed in IR oven at various conveyor speeds and various distances between IR lamps and headlight surface. In theoretical study, a mathematical model was developed for the headlights surface temperature by using heat transfer theory. The results obtained by the mathematical model and the measurement showed very good agreement with a 6.5 % average error. It is shown that mathematical models can be used to estimate the surface temperatures when the oven is operated under different conditions.

  19. Ultrasensitive string-based temperature sensors

    DEFF Research Database (Denmark)

    Larsen, Tom; Schmid, Silvan; Gronberg, L.

    2011-01-01

    Resonant strings are a promising concept for ultra sensitive temperature detection. We present an analytical model for the sensitivity with which we optimize the temperature response of resonant strings by varying geometry and material. The temperature sensitivity of silicon nitride and aluminum ...

  20. Surface layer temperature inversion in the Arabian Sea during winter

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Ghosh, A.K.

    picture of the actual inversion phenomena occurring in this area. Figure 1 illustrates the procedure adopted in finding the inversion stations. If the temperature difference (Del T) obtained from (T U –T L ) is greater than 0.2°C, then the station... is more or less consistent. Figure 3-A shows the frequency distribution of temperature difference of the inversion layer (Del T). Figure 3-B shows the frequency distribution of the thickness of the inversion layers in meters (Di). Del T is distributed over...

  1. Surface characterization of low-temperature grown yttrium oxide

    Science.gov (United States)

    Krawczyk, Mirosław; Lisowski, Wojciech; Pisarek, Marcin; Nikiforow, Kostiantyn; Jablonski, Aleksander

    2018-04-01

    The step-by-step growth of yttrium oxide layer was controlled in situ using X-ray photoelectron spectroscopy (XPS). The O/Y atomic concentration (AC) ratio in the surface layer of finally oxidized Y substrate was found to be equal to 1.48. The as-grown yttrium oxide layers were then analyzed ex situ using combination of Auger electron spectroscopy (AES), elastic-peak electron spectroscopy (EPES) and scanning electron microscopy (SEM) in order to characterize their surface chemical composition, electron transport phenomena and surface morphology. Prior to EPES measurements, the Y oxide surface was pre-sputtered by 3 kV argon ions, and the resulting AES-derived composition was found to be Y0.383O0.465C0.152 (O/Y AC ratio of 1.21). The SEM images revealed different surface morphology of sample before and after Ar sputtering. The oxide precipitates were observed on the top of un-sputtered Y oxide layer, whereas the oxide growth at the Ar ion-sputtered surface proceeded along defects lines normal to the layer plane. The inelastic mean free path (IMFP) characterizing electron transport was evaluated as a function of energy in the range of 0.5-2 keV from the EPES method. Two reference materials (Ni and Au) were used in these measurements. Experimental IMFPs determined for the Y0.383O0.465C0.152 and Y2O3 surface compositions, λ, were uncorrected for surface excitations and approximated by the simple function λ = kEp at electron energies E between 500 eV and 2000 eV, where k and p were fitted parameters. These values were also compared with IMFPs resulting from the TPP-2 M predictive equation for both oxide compositions. The fitted functions were found to be reasonably consistent with the measured and predicted IMFPs. In both cases, the average value of the mean percentage deviation from the fits varied between 5% and 37%. The IMFPs measured for Y0.383O0.465C0.152 surface composition were found to be similar to the IMFPs for Y2O3.

  2. Influence of liquid temperature and flow rate on enamel erosion and surface softening.

    Science.gov (United States)

    Eisenburger, M; Addy, M

    2003-11-01

    Enamel erosion and softening are based on chemical processes which could be influenced by many factors including temperature and acid flow rate. Knowledge of the influence of these variables could have relevance to research experiments and clinical outcomes. Both parameters were investigated using an ultrasonication and profilometry method to assess erosion depth and surface softening of enamel. The influence of temperature was studied by eroding polished human enamel samples at 4, 20, 35 or 50 degrees C for 2 h. Secondly, different liquid flow conditions were established by varying acid agitation. Additionally, a slow laminar flow and a jet of citric acid, to simulate drinking through a straw, were applied to specimens. Erosion depth increased significantly with acid temperature from 11.0 microm at 4 degrees C to 35.8 microm at 50 degrees C. Surface softening increased much more slowly and plateaued at 2.9 microm to 3.5 microm after 35 degrees C. A strong dependence of erosion on liquid flow was revealed. In unstirred conditions only 8.6 microm erosion occurred, which increased to 22.2 microm with slow stirring and 40.9 microm with fast stirring. Surface softening did not increase correspondingly with its largest extent at slow stirring at 3.4 microm.The implication of these data are: first, the conditions for erosion experiments in vitro or in situ need to be specified for reliable comparisons between studies. Secondly, erosion of teeth by soft drinks are likely to be influenced both by the temperature of the drink and individual drinking habits.

  3. Role of the Soil Thermal Inertia in the short term variability of the surface temperature and consequences for the soil-moisture temperature feedback

    Science.gov (United States)

    Cheruy, Frederique; Dufresne, Jean-Louis; Ait Mesbah, Sonia; Grandpeix, Jean-Yves; Wang, Fuxing

    2017-04-01

    A simple model based on the surface energy budget at equilibrium is developed to compute the sensitivity of the climatological mean daily temperature and diurnal amplitude to the soil thermal inertia. It gives a conceptual framework to quantity the role of the atmospheric and land surface processes in the surface temperature variability and relies on the diurnal amplitude of the net surface radiation, the sensitivity of the turbulent fluxes to the surface temperature and the thermal inertia. The performances of the model are first evaluated with 3D numerical simulations performed with the atmospheric (LMDZ) and land surface (ORCHIDEE) modules of the Institut Pierre Simon Laplace (IPSL) climate model. A nudging approach is adopted, it prevents from using time-consuming long-term simulations required to account for the natural variability of the climate and allow to draw conclusion based on short-term (several years) simulations. In the moist regions the diurnal amplitude and the mean surface temperature are controlled by the latent heat flux. In the dry areas, the relevant role of the stability of the boundary layer and of the soil thermal inertia is demonstrated. In these regions, the sensitivity of the surface temperature to the thermal inertia is high, due to the high contribution of the thermal flux to the energy budget. At high latitudes, when the sensitivity of turbulent fluxes is dominated by the day-time sensitivity of the sensible heat flux to the surface temperature and when this later is comparable to the thermal inertia term of the sensitivity equation, the surface temperature is also partially controlled by the thermal inertia which can rely on the snow properties; In the regions where the latent heat flux exhibits a high day-to-day variability, such as transition regions, the thermal inertia has also significant impact on the surface temperature variability . In these not too wet (energy limited) and not too dry (moisture-limited) soil moisture (SM

  4. Quantifying Uncertainty in Satellite-Retrieved Land Surface Temperature from Cloud Detection Errors

    Directory of Open Access Journals (Sweden)

    Claire E. Bulgin

    2018-04-01

    Full Text Available Clouds remain one of the largest sources of uncertainty in remote sensing of surface temperature in the infrared, but this uncertainty has not generally been quantified. We present a new approach to do so, applied here to the Advanced Along-Track Scanning Radiometer (AATSR. We use an ensemble of cloud masks based on independent methodologies to investigate the magnitude of cloud detection uncertainties in area-average Land Surface Temperature (LST retrieval. We find that at a grid resolution of 625 km 2 (commensurate with a 0.25 ∘ grid size at the tropics, cloud detection uncertainties are positively correlated with cloud-cover fraction in the cell and are larger during the day than at night. Daytime cloud detection uncertainties range between 2.5 K for clear-sky fractions of 10–20% and 1.03 K for clear-sky fractions of 90–100%. Corresponding night-time uncertainties are 1.6 K and 0.38 K, respectively. Cloud detection uncertainty shows a weaker positive correlation with the number of biomes present within a grid cell, used as a measure of heterogeneity in the background against which the cloud detection must operate (e.g., surface temperature, emissivity and reflectance. Uncertainty due to cloud detection errors is strongly dependent on the dominant land cover classification. We find cloud detection uncertainties of a magnitude of 1.95 K over permanent snow and ice, 1.2 K over open forest, 0.9–1 K over bare soils and 0.09 K over mosaic cropland, for a standardised clear-sky fraction of 74.2%. As the uncertainties arising from cloud detection errors are of a significant magnitude for many surface types and spatially heterogeneous where land classification varies rapidly, LST data producers are encouraged to quantify cloud-related uncertainties in gridded products.

  5. EFFECTS OF PAVEMENT SURFACE TEMPERATURE ON THE MODIFICATION OF URBAN THERMAL ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    SARAT, Adebayo-Aminu

    2012-07-01

    Full Text Available Urban centres continue to experience escalating average summer temperature over the last fifty years. Temperature in the urban core cites have been rising due to rapid growth of urbanization in the latter half of the twentieth century (Akbari et al., 1989. Outdoor experiments were conducted to investigate the effects of different movement of materials on the urban thermal environment. Meteorological conditions such as air temperature, pavement surface temperature, Relative humidity and wind velocity were recorded to determine temperature differences among Asphalt/concrete, interlocking bricks and grass surfaces.

  6. Determination of surface temperatures in combustion environments using thermographic phosphors; Wandtemperaturmessungen in Verbrennungsumgebungen mithilfe thermographischer Phosphore

    Energy Technology Data Exchange (ETDEWEB)

    Bruebach, J.; Kissel, T. [TU Darmstadt (Germany). FG Energie- und Kraftwerkstechnik; Dreizler, A. [TU Darmstadt (Germany). FG Reaktive Stroemungen und Messtechnik

    2009-07-01

    A phosphor thermometry system was characterised with regard to all sources of systematic errors. Exemplary, the point measurement of a surface temperature and the determination of wall-normal temperature gradients within an optically accessible combustion chamber are outlined. Furthermore, the temporal temperature characteristic at the quartz ring of an optically accessible engine is presented. (orig.)

  7. Design and evaluation of an inexpensive radiation shield for monitoring surface air temperatures

    Science.gov (United States)

    Zachary A. Holden; Anna E. Klene; Robert F. Keefe; Gretchen G. Moisen

    2013-01-01

    Inexpensive temperature sensors are widely used in agricultural and forestry research. This paper describes a low-cost (~3 USD) radiation shield (radshield) designed for monitoring surface air temperatures in harsh outdoor environments. We compared the performance of the radshield paired with low-cost temperature sensors at three sites in western Montana to several...

  8. Temperature processes at two sliding surfaces subjected to dry friction

    Czech Academy of Sciences Publication Activity Database

    Půst, Ladislav; Pešek, Luděk; Cibulka, Jan; Bula, Vítězslav

    2012-01-01

    Roč. 63, 5/6 (2012), s. 277-292 ISSN 0039-2472 R&D Projects: GA ČR GA101/09/1166 Institutional support: RVO:61388998 Keywords : dry friction * vibration damping * experimental set * increase of temperature * lost energy Subject RIV: BI - Acoustics

  9. Unravelling Diurnal Asymmetry of Surface Temperature in Different Climate Zones.

    Science.gov (United States)

    Vinnarasi, R; Dhanya, C T; Chakravorty, Aniket; AghaKouchak, Amir

    2017-08-04

    Understanding the evolution of Diurnal Temperature Range (DTR), which has contradicting global and regional trends, is crucial because it influences environmental and human health. Here, we analyse the regional evolution of DTR trend over different climatic zones in India using a non-stationary approach known as the Multidimensional Ensemble Empirical Mode Decomposition (MEEMD) method, to explore the generalized influence of regional climate on DTR, if any. We report a 0.36 °C increase in overall mean of DTR till 1980, however, the rate has declined since then. Further, arid deserts and warm-temperate grasslands exhibit negative DTR trends, while the west coast and sub-tropical forest in the north-east show positive trends. This transition predominantly begins with a 0.5 °C increase from the west coast and spreads with an increase of 0.25 °C per decade. These changes are more pronounced during winter and post-monsoon, especially in the arid desert and warm-temperate grasslands, the DTR decreased up to 2 °C, where the rate of increase in minimum temperature is higher than the maximum temperature. We conclude that both maximum and minimum temperature increase in response to the global climate change, however, their rates of increase are highly local and depend on the underlying climatic zone.

  10. Surface Temperature Prediction of a Bridge for Tactical Decision Aide Modelling

    Science.gov (United States)

    1988-01-01

    Roadway And Piling Surface Temperature Predictions (No Radiosity Incident on Lower Surface) Compared to Temperature Estimates...Heat gained from water = Heat lost by long wave radiosity radiation. Algebraically, with the conduction term expressed in the same manner as for...5 10 15 20 LOCAL TIME (hrs.) Figure 8. Effect of No Radiosity Incident on Lower Surface. 37 U 8a M OT U% 60-- 0- o.. 20- 0- 1 T I I 5 10 15 20 LOCAL

  11. CHF Enhancement by Surface Patterning based on Hydrodynamic Instability Model

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Han; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of)

    2015-05-15

    If the power density of a device exceeds the CHF point, bubbles and vapor films will be covered on the whole heater surface. Because vapor films have much lower heat transfer capabilities compared to the liquid layer, the temperature of the heater surface will increase rapidly, and the device could be damaged due to the heater burnout. Therefore, the prediction and the enhancement of the CHF are essential to maximizing the efficient heat removal region. Numerous studies have been conducted to describe the CHF phenomenon, such as hydrodynamic instability theory, macrolayer dryout theory, hot/dry spot theory, and bubble interaction theory. The hydrodynamic instability model, proposed by Zuber, is the predominant CHF model that Helmholtz instability attributed to the CHF. Zuber assumed that the Rayleigh-Taylor (RT) instability wavelength is related to the Helmholtz wavelength. Lienhard and Dhir proposed a CHF model that Helmholtz instability wavelength is equal to the most dangerous RT wavelength. In addition, they showed the heater size effect using various heater surfaces. Lu et al. proposed a modified hydrodynamic theory that the Helmholtz instability was assumed to be the heater size and the area of the vapor column was used as a fitting factor. The modified hydrodynamic theories were based on the change of Helmholtz wavelength related to the RT instability wavelength. In the present study, the change of the RT instability wavelength, based on the heater surface modification, was conducted to show the CHF enhancement based on the heater surface patterning in a plate pool boiling. Sapphire glass was used as a base heater substrate, and the Pt film was used as a heating source. The patterning surface was based on the change of RT instability wavelength. In the present work the study of the CHF was conducted using bare Pt and patterned heating surfaces.

  12. Enhanced adhesion between carbon nanotubes and substrate surfaces by low-temperature annealing

    International Nuclear Information System (INIS)

    Jang, Chi Woong; Byun, Young Tae; Woo, Deok Ha; Lee, Seok; Jhon, Young Min

    2012-01-01

    We enhanced the adhesion forces between carbon nanotubes (CNTs) and the substrate surface by using a low-temperature annealing process at 180 .deg. C for 300 s to protect the CNTs throughout the processes in photolithography for fabricating CNT-based devices, especially ion and bio sensors which are always exposed to liquids. The adhesion force was tested by using the adhesion durability test of soaking the fabricated CNT field effect transistors (CNT-FETs) in de-ionized water at room temperature for 300 s, and the adsorption quantities of CNTs were analyzed by using I - V measurements on the CNT-FETs before and after each adhesion durability test. The conductance change of the CNT-FETs fabricated with the annealing process was considerably decreased by more than a factor of 10 5 compared to that without the annealing process, implying that CNTs adhere much more strongly to the substrate after the annealing process.

  13. Analysis of relationships between land surface temperature and land use changes in the Yellow River Delta

    Science.gov (United States)

    Ning, Jicai; Gao, Zhiqiang; Meng, Ran; Xu, Fuxiang; Gao, Meng

    2018-06-01

    This study analyzed land use and land cover changes and their impact on land surface temperature using Landsat 5 Thematic Mapper and Landsat 8 Operational Land Imager and Thermal Infrared Sensor imagery of the Yellow River Delta. Six Landsat images comprising two time series were used to calculate the land surface temperature and correlated vegetation indices. The Yellow River Delta area has expanded substantially because of the deposited sediment carried from upstream reaches of the river. Between 1986 and 2015, approximately 35% of the land use area of the Yellow River Delta has been transformed into salterns and aquaculture ponds. Overall, land use conversion has occurred primarily from poorly utilized land into highly utilized land. To analyze the variation of land surface temperature, a mono-window algorithm was applied to retrieve the regional land surface temperature. The results showed bilinear correlation between land surface temperature and the vegetation indices (i.e., Normalized Difference Vegetation Index, Adjusted-Normalized Vegetation Index, Soil-Adjusted Vegetation Index, and Modified Soil-Adjusted Vegetation Index). Generally, values of the vegetation indices greater than the inflection point mean the land surface temperature and the vegetation indices are correlated negatively, and vice versa. Land surface temperature in coastal areas is affected considerably by local seawater temperature and weather conditions.

  14. Preliminary study of the relationship between surface and bulk water temperatures at the Dresden cooling pond

    International Nuclear Information System (INIS)

    Wesely, M.L.; Hicks, B.B.; Hess, G.D.

    1975-01-01

    Successful application of bulk aerodynamic formulae to determine the vertical sensible and latent heat fluxes above a cooling lake requires accurate estimates of water surface temperature. Because of the heat loss at the surface and partial insulation by the poorly-mixed outer skin of water in contact with the air-water interface, the surface temperature is usually 0.1 to 2.0 C less than the temperature at a depth greater than 1 cm. For engineering applications requiring estimates of the total heat dissipation capacity of a particular cooling lake, the bulk temperature of the entire mixed layer of subsurface water is more important than the surface temperature. Therefore, in order to simulate the thermal performance of a cooling pond, both the surface temperature and the bulk temperature should be estimated. In the case of cooling ponds, the total heat transfer through the uppermost layer is extremely large and the water beneath the surface is strongly mixed by circulation currents within the pond. The purpose of this report is to describe the magnitude of the temperature difference across the surface skin at the Dresden nuclear power plant cooling pond and to relate this difference to variables used in modeling the thermal performance of cooling ponds

  15. SPATIAL AND TEMPORAL VARIATION OF LAND SURFACE TEMPERATURE IN FUJIAN PROVINCE FROM 2001 TO 2015

    Directory of Open Access Journals (Sweden)

    Y. Li

    2018-04-01

    Full Text Available Land surface temperature (LST is an essential parameter in the physics of land surface processes. The spatiotemporal variations of LST on the Fujian province were studied using AQUA Moderate Resolution Imaging Spectroradiometer LST data. Considering the data gaps in remotely sensed LST products caused by cloud contamination, the Savitzky-Golay (S-G filter method was used to eliminate the influence of cloud cover and to describe the periodical signals of LST. Observed air temperature data from 27 weather stations were employed to evaluate the fitting performance of the S-G filter method. Results indicate that S-G can effectively fit the LST time series and remove the influence of cloud cover. Based on the S-G-derived result, Spatial and temporal Variations of LST in Fujian province from 2001 to 2015 are analysed through slope analysis. The results show that: 1 the spatial distribution of annual mean LST generally exhibits consistency with altitude in the study area and the average of LST was much higher in the east than in the west. 2 The annual mean temperature of LST declines slightly among 15 years in Fujian. 3 Slope analysis reflects the spatial distribution characteristics of LST changing trend in Fujian.Improvement areas of LST are mainly concentrated in the urban areas of Fujian, especially in the eastern urban areas. Apparent descent areas are mainly distributed in the area of Zhangzhou and eastern mountain area.

  16. Spatial and Temporal Variation of Land Surface Temperature in Fujian Province from 2001 TO 2015

    Science.gov (United States)

    Li, Y.; Wang, X.; Ding, Z.

    2018-04-01

    Land surface temperature (LST) is an essential parameter in the physics of land surface processes. The spatiotemporal variations of LST on the Fujian province were studied using AQUA Moderate Resolution Imaging Spectroradiometer LST data. Considering the data gaps in remotely sensed LST products caused by cloud contamination, the Savitzky-Golay (S-G) filter method was used to eliminate the influence of cloud cover and to describe the periodical signals of LST. Observed air temperature data from 27 weather stations were employed to evaluate the fitting performance of the S-G filter method. Results indicate that S-G can effectively fit the LST time series and remove the influence of cloud cover. Based on the S-G-derived result, Spatial and temporal Variations of LST in Fujian province from 2001 to 2015 are analysed through slope analysis. The results show that: 1) the spatial distribution of annual mean LST generally exhibits consistency with altitude in the study area and the average of LST was much higher in the east than in the west. 2) The annual mean temperature of LST declines slightly among 15 years in Fujian. 3) Slope analysis reflects the spatial distribution characteristics of LST changing trend in Fujian.Improvement areas of LST are mainly concentrated in the urban areas of Fujian, especially in the eastern urban areas. Apparent descent areas are mainly distributed in the area of Zhangzhou and eastern mountain area.

  17. Mechanisms Controlling Global Mean Sea Surface Temperature Determined From a State Estimate

    Science.gov (United States)

    Ponte, R. M.; Piecuch, C. G.

    2018-04-01

    Global mean sea surface temperature (T¯) is a variable of primary interest in studies of climate variability and change. The temporal evolution of T¯ can be influenced by surface heat fluxes (F¯) and by diffusion (D¯) and advection (A¯) processes internal to the ocean, but quantifying the contribution of these different factors from data alone is prone to substantial uncertainties. Here we derive a closed T¯ budget for the period 1993-2015 based on a global ocean state estimate, which is an exact solution of a general circulation model constrained to most extant ocean observations through advanced optimization methods. The estimated average temperature of the top (10-m thick) level in the model, taken to represent T¯, shows relatively small variability at most time scales compared to F¯, D¯, or A¯, reflecting the tendency for largely balancing effects from all the latter terms. The seasonal cycle in T¯ is mostly determined by small imbalances between F¯ and D¯, with negligible contributions from A¯. While D¯ seems to simply damp F¯ at the annual period, a different dynamical role for D¯ at semiannual period is suggested by it being larger than F¯. At periods longer than annual, A¯ contributes importantly to T¯ variability, pointing to the direct influence of the variable ocean circulation on T¯ and mean surface climate.

  18. Surface temperatures in New York City: Geospatial data enables the accurate prediction of radiative heat transfer.

    Science.gov (United States)

    Ghandehari, Masoud; Emig, Thorsten; Aghamohamadnia, Milad

    2018-02-02

    Despite decades of research seeking to derive the urban energy budget, the dynamics of thermal exchange in the densely constructed environment is not yet well understood. Using New York City as a study site, we present a novel hybrid experimental-computational approach for a better understanding of the radiative heat transfer in complex urban environments. The aim of this work is to contribute to the calculation of the urban energy budget, particularly the stored energy. We will focus our attention on surface thermal radiation. Improved understanding of urban thermodynamics incorporating the interaction of various bodies, particularly in high rise cities, will have implications on energy conservation at the building scale, and for human health and comfort at the urban scale. The platform presented is based on longwave hyperspectral imaging of nearly 100 blocks of Manhattan, in addition to a geospatial radiosity model that describes the collective radiative heat exchange between multiple buildings. Despite assumptions in surface emissivity and thermal conductivity of buildings walls, the close comparison of temperatures derived from measurements and computations is promising. Results imply that the presented geospatial thermodynamic model of urban structures can enable accurate and high resolution analysis of instantaneous urban surface temperatures.

  19. Interannual variability of sea surface temperature and circulation in ...

    African Journals Online (AJOL)

    Local surface heat flux exchanges driven by the anomalous shortwave radiation dominated the interannual SST variability in the Tanzanian shelf region, with some contribution by the advection of heat anomalies from the North-East Madagascar Current. Farther offshore, the interannual variability of the SST was dominated ...

  20. Sea surface temperature mapping using a thermal infrared scanner

    Digital Repository Service at National Institute of Oceanography (India)

    RameshKumar, M.R; Pandya, R; Mathur, K.M.; Charyulu, R; Rao, L.V.G.

    1 metre water column below the sea surface. A thermal infrared scanner developed by the Space Applications Centre (ISRO), Ahmedabad was operated on board R.V. Gaveshani in April/May 1984 for mapping SST over the eastern Arabian Sea. SST values...

  1. New Stainless Steel Alloys for Low Temperature Surface Hardening?

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Dahl, Kristian Vinter; Somers, Marcel A. J.

    2015-01-01

    The present contribution showcases the possibility for developing new surface hardenable stainless steels containing strong nitride/carbide forming elements (SNCFE). Nitriding of the commercial alloys, austenitic A286, and ferritic AISI 409 illustrates the beneficial effect of having SNCFE presen...

  2. Levitation of Liquid Microdroplets Above A Solid Surface Subcooled to the Leidenfrost Temperature

    Directory of Open Access Journals (Sweden)

    Kirichenko D. P.

    2016-01-01

    Full Text Available Evaporation of liquid microdroplets that fall on a solid surface with the temperature of below the Leidenfrost temperature is studied. It has been found out that sufficiently small liquid droplets of about 10 microns can suspend at some distance from the surface (levitate and do not reach the surface; at that, the rate of droplet evaporation is reduced by an order as compared to microdroplets, which touch the surface. It is determined that in contrast to microdroplets, which touch the surface, the specific evaporation rate of levitating droplets is constant in time.

  3. Observation on Surface Change of Fragile Glass: Temperature - Time Dependence Studied by X-Ray Reflectivity

    International Nuclear Information System (INIS)

    Kikkawa, Hiroyuki; Kitahara, Amane; Takahashi, Isao

    2004-01-01

    The structural change of a fragile glass surface close to the glass transition temperature Tg is studied by using X-ray reflectivity. Measurements were performed on surfaces of maltitol, which is a typical polyalcohol fragile glass with Tg = 320K. Upon both heating and cooling, we find the following features which are also noticed in silicate glass surfaces: (i) On heating, the surface morphology indicates a variation at temperatures below Tg; (ii) A drastic increase in surface roughness occurs at a temperature about 333K on heating, which is 13K higher than Tg; (iii) During the cooling of the sample, formation of a low-density surface layer (3nm at 293K) is observed. Prior to the crystallization, nm - μm sized domains were grown at the surface, which might not be reported for other glasses

  4. Urban surface temperature behaviour and heat island effect in a tropical planned city

    Science.gov (United States)

    Ahmed, Adeb Qaid; Ossen, Dilshan Remaz; Jamei, Elmira; Manaf, Norhashima Abd; Said, Ismail; Ahmad, Mohd Hamdan

    2015-02-01

    Putrajaya is a model city planned with concepts of a "city in the garden" and an "intelligent city" in the tropics. This study presents the behaviour of the surface temperature and the heat island effect of Putrajaya. Findings show that heat island intensity is 2 °C on average at nighttime and negligible at daytime. But high surface temperature values were recorded at the main boulevard due to direct solar radiation incident, street orientation in the direction of northeast and southwest and low building height-to-street width ratio. Buildings facing each other had cooling effect on surfaces during the morning and evening hours; conversely, they had a warming effect at noon. Clustered trees along the street are effective in reducing the surface temperature compared to scattered and isolated trees. Surface temperature of built up areas was highest at noon, while walls and sidewalks facing northwest were hottest later in the day. Walls and sidewalks that face northwest were warmer than those that face southeast. The surface temperatures of the horizontal street surfaces and of vertical façades are at acceptable levels relative to the surface temperature of similar surfaces in mature cities in subtropical, temperate and Mediterranean climates.

  5. A method of surface area measurement of fuel materials by fission gas release at low temperature

    International Nuclear Information System (INIS)

    Kaimal, K.N.G.; Naik, M.C.; Paul, A.R.; Venkateswarlu, K.S.

    1989-01-01

    The present report deals with the development of a method for surface area measurement of nuclear fuel as well as fissile doped materials by fission gas release study at low temperature. The method is based on the evaluation of knock-out release rate of fission 133 Xe from irradiated fuel after sufficient cooling to decay the short lived activity. The report also describes the fabrication of an ampoule breaker unit for such study. Knock-out release rate of 133 Xe has been studied from UO 2 powders having varying surface area 'S' ranging from 270 cm 2 /gm to 4100 cm 2 /gm at two fissioning rates 10 12 f/cm 3 . sec. and 3.2x10 10 f/cm.sec. A relation between K and A has been established and discussed in this report. (author). 6 refs

  6. Multimodel Surface Temperature Responses to Removal of U.S. Sulfur Dioxide Emissions

    Science.gov (United States)

    Conley, A. J.; Westervelt, D. M.; Lamarque, J.-F.; Fiore, A. M.; Shindell, D.; Correa, G.; Faluvegi, G.; Horowitz, L. W.

    2018-03-01

    Three Earth System models are used to derive surface temperature responses to removal of U.S. anthropogenic SO2 emissions. Using multicentury perturbation runs with and without U.S. anthropogenic SO2 emissions, the local and remote surface temperature changes are estimated. In spite of a temperature drift in the control and large internal variability, 200 year simulations yield statistically significant regional surface temperature responses to the removal of U.S. SO2 emissions. Both local and remote surface temperature changes occur in all models, and the patterns of changes are similar between models for northern hemisphere land regions. We find a global average temperature sensitivity to U.S. SO2 emissions of 0.0055 K per Tg(SO2) per year with a range of (0.0036, 0.0078). We examine global and regional responses in SO4 burdens, aerosol optical depths (AODs), and effective radiative forcing (ERF). While changes in AOD and ERF are concentrated near the source region (United States), the temperature response is spread over the northern hemisphere with amplification of the temperature increase toward the Arctic. In all models, we find a significant response of dust concentrations, which affects the AOD but has no obvious effect on surface temperature. Temperature sensitivity to the ERF of U.S. SO2 emissions is found to differ from the models' sensitivity to radiative forcing of doubled CO2.

  7. Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference

    Science.gov (United States)

    Castro, Sandra L.; Emery, William J.

    2002-01-01

    The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. During this one year grant, design and construction of an improved infrared radiometer was completed and testing was initiated. In addition, development of an improved parametric model for the bulk-skin temperature difference was completed using data from the previous version of the radiometer. This model will comprise a key component of an improved procedure for estimating the bulk SST from satellites. The results comprised a significant portion of the Ph.D. thesis completed by one graduate student and they are currently being converted into a journal publication.

  8. Retrieval of sea surface air temperature from satellite data over Indian Ocean: An empirical approach

    Digital Repository Service at National Institute of Oceanography (India)

    Sathe, P.V.; Muraleedharan, P.M.

    the sea surface air temperature from satellite derived sea surface humidity in the Indian Ocean. Using the insitu data on surface met parameters collected on board O.R.V. Sagar Kanya in the Indian Ocean over a period of 15 years, the relationship between...

  9. MISST: The Multi-Sensor Improved Sea Surface Temperature Project

    Science.gov (United States)

    2009-06-01

    floods or droughts over land, with associated changes in agricul- tural crop yields. Coral bleaching due to warm ocean temperatures can result in...water circulation (Manzello et al., 2007), hard corals can expel these colorful symbionts from their tissues, resulting in the "paling" or " bleaching ...34 of corals . Bleaching hinders the ability of corals to replace erosion with new growth, and in extreme cases can contribute to mass coral mortality

  10. Preparation and Characterization of High Temperature Superconductor Film Surfaces

    Science.gov (United States)

    1993-10-27

    Lanthanum Strontium Copper Oxide (LSCO) was also tested as a normal metal overlayer because of its compatibility with the high deposition temperature for...fabricate YBCO/ISCO SEB junctions using a variety of step heights (110 nm - 330 nm) on Neodymium Gallate (NGO) substrates. NGO was chosen as a...substrate because of its excellent lattice match to YBCO and its lack of crystal twinning Twinning had been a drawback of Lanthanum Aluminate (LAO)- L

  11. Assessment Of Surface-Catalyzed Reaction Products From High Temperature Materials In Plasmas

    Science.gov (United States)

    Allen, Luke Daniel

    Current simulations of atmospheric entry into both Mars and Earth atmospheres for the design of thermal protections systems (TPS) typically invoke conservative assumptions regarding surface-catalyzed recombination and the amount of energy deposited on the surface. The need to invoke such assumptions derives in part from lack of adequate experimental data on gas-surface interactions at trajectory relevant conditions. Addressing this issue, the University of Vermont's Plasma Test and Diagnostics Laboratory has done extensive work to measure atomic specie consumption by measuring the concentration gradient over various material surfaces. This thesis extends this work by attempting to directly diagnose molecular species production in air plasmas. A series of spectral models for the A-X and B-X systems of nitric oxide (NO), and the B-X system of boron monoxide (BO) have been developed. These models aim to predict line positions and strengths for the respective molecules in a way that is best suited for the diagnostic needs of the UVM facility. From the NO models, laser induced fluorescence strategies have been adapted with the intent of characterizing the relative quantity and thermodynamic state of NO produced bysurface-catalyzed recombination, while the BO model adds a diagnostic tool for the testing of diboride-based TPS materials. Boundary layer surveys of atomic nitrogen and NO have been carried out over water-cooled copper and nickel surfaces in air/argon plasmas. Translation temperatures and relative number densities throughout the boundary layer are reported. Additional tests were also conducted over a water-cooled copper surface to detect evidence of highly non-equilibrium effects in the form of excess population in elevated vibrational levels of the A-X system of NO. The tests showed that near the sample surface there is a much greater population in the upsilon'' = 1ground state than is predicted by a Boltzmann distribution.

  12. Manifestation of two meddies in altimetry and sea-surface temperature

    Directory of Open Access Journals (Sweden)

    I. Bashmachnikov

    2013-03-01

    Full Text Available Two meddies were identified in the Iberian Basin using shipboard ADCP (Meddy 1 and Argo float (Meddy 2 in contrasting background conditions. Meddy 1 was observed while interacting with the Azores Current (AzC, while Meddy 2 was observed in a much calmer dynamical background, north from the AzC jet. In both cases the meddies formed a clear anticyclonic surface signal, detectable in altimetry as well as in sea-surface temperature (SST. Analysis of the in situ observations of the dynamic signal over Meddy 1 showed that the signal, generated by the moving meddy, dominated the AzC dynamics at least up to the base of the seasonal thermocline even at the late stages of its interaction with the jet. The centre of rotation of the surface signal was shifted south-westward from the axis of the meddy by about 18 km, and its dynamic radius was 2 times bigger than that of the meddy. In the centre of the anticyclonic surface signals of both meddies, SST was colder than that of the surrounding water, in contrast to warm SST anomalies in the cores of surface anticyclones generated by meandering surface currents. The latter difference gives ground for identification of meddies (as well as other sub-surface anticyclones in comparatively dynamically calm regions using coupled altimetry–SST remote sensing data. An identification of Meddy 1 prior to the shipboard ADCP measurements was the first successful experience. At the same time, SST anomalies over the meddies were rather weak, often unstable and statistically significant only over periods of months.

  13. Surface properties of copper based cermet materials

    International Nuclear Information System (INIS)

    Voinea, M.; Vladuta, C.; Bogatu, C.; Duta, A.

    2008-01-01

    The paper presents the characterization of the surface properties of copper based cermets obtained by two different techniques: spray pyrolysis deposition (SPD) and electrodeposition. Copper acetate was used as precursor of Cu/CuO x cermet. The surface morphology was tailored by adding copolymers of maleic anhydride with controlled hydrophobia. The films morphology of Cu/CuO x was assessed using contact angle measurements and AFM analysis. The porous structures obtained via SPD lead to higher liquid adsorption rate than the electrodeposited films. A highly polar liquid - water is recommended as testing liquid in contact angle measurements, for estimating the porosity of copper based cermets, while glycerol can be used to distinguish among ionic and metal predominant structures. Thus, contact angle measurements can be used for a primary evaluation of the films morphology and, on the other hand, of the ratio between the cermet components

  14. Sea surface temperature and Ekman transport in the Persian Gulf

    Directory of Open Access Journals (Sweden)

    E. H.

    2002-12-01

    Full Text Available   The wind drift motion of the water which is produced by the stress of the wind exerted upon the surface of the ocean is described by Ekmans theory (1905. Using the mean monthly values for the wind stress and SST, seasonal Ekman transport for the Persian Gulf was computed and contoured. The geostrophic winds have combined with the SST to estimate the effect of cooling due to Ekman transport of colder northern waters and inflow from the Oman Sea. The monthly SST mainly obtained from the 10 10 grided data of Levitus atlas and Hormuz Cruis Experiment for 1997.   Analyses show a NW to SE Ekman transport due to wind stress and significant interannual variability of SST on sea surface in the Persian Gulf. The seasonal variation of SST shows a continental pattern due to severe interaction between the land and sea. But these variations somehow moderates because of Ekman transport in Persian Gulf.

  15. Temperature effects on surface activity and application in oxidation ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. The γcmc values of CTAB–SDS decrease from 63⋅67 mN/m at 10°C to 36⋅38 mN/m at 90°C, slightly lower than those of either CTAB or SDS. Correspondingly, the CMC of CTAB–SDS decreases almost by half. The increase of surface activity of CTAB–SDS can be attributed to the relatively weak electrostatic ...

  16. Surface multifragmentation investigated with a finite temperature spherical TDHF model

    International Nuclear Information System (INIS)

    Ngo, H.; Ighezou, F.Z.; Paula, L. De

    1992-01-01

    A model for multifragmentation caused by heavy ion collision is developed. The initial state is a hot and compressed spherical nucleus in thermal equilibrium. The dynamical evolution of this nucleus is studied. The nuclear density of the system is calculated with mean field approximation. It is shown that, in some cases, the surface of the nucleus breaks up before its volume. (K.A.) 8 refs.; 1 fig

  17. Soil surface temperatures reveal moderation of the urban heat island effect by trees and shrubs.

    Science.gov (United States)

    Edmondson, J L; Stott, I; Davies, Z G; Gaston, K J; Leake, J R

    2016-09-19

    Urban areas are major contributors to air pollution and climate change, causing impacts on human health that are amplified by the microclimatological effects of buildings and grey infrastructure through the urban heat island (UHI) effect. Urban greenspaces may be important in reducing surface temperature extremes, but their effects have not been investigated at a city-wide scale. Across a mid-sized UK city we buried temperature loggers at the surface of greenspace soils at 100 sites, stratified by proximity to city centre, vegetation cover and land-use. Mean daily soil surface temperature over 11 months increased by 0.6 °C over the 5 km from the city outskirts to the centre. Trees and shrubs in non-domestic greenspace reduced mean maximum daily soil surface temperatures in the summer by 5.7 °C compared to herbaceous vegetation, but tended to maintain slightly higher temperatures in winter. Trees in domestic gardens, which tend to be smaller, were less effective at reducing summer soil surface temperatures. Our findings reveal that the UHI effects soil temperatures at a city-wide scale, and that in their moderating urban soil surface temperature extremes, trees and shrubs may help to reduce the adverse impacts of urbanization on microclimate, soil processes and human health.

  18. Radiative surface temperatures of the burned and unburned areas in a tallgrass prairie

    International Nuclear Information System (INIS)

    Asrar, G.; Harris, T.R.; Lapitan, R.L.; Cooper, D.I.

    1988-01-01

    This study was conducted in a natural tallgrass prairie area in the Flint Hills of Kansas. Our objective was to evaluate the surface radiative temperatures of burned and unburned treatments of the grassland as a means of delineating the areas covered by each treatment. Burning is used to remove the senescent vegetation resulting from the previous year's growth. Surface temperatures were obtained in situ and by an airborne scanner. Burned and unburned grass canopies had distinctly different diurnal surface radiative temperatures. Measurements of surface energy balance components revealed a difference in partitioning of the available energy between the two canopies, which resulted in the difference in their measured surface temperatures. The magnitude of this difference is dependent on the time of measurements and topographic conditions. (author)

  19. Measurement of surface temperature profiles on liquid uranium metal during electron beam evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Ohba, Hironori; Shibata, Takemasa [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-11-01

    Surface temperature distributions of liquid uranium in a water-cooled copper crucible during electron beam evaporation were measured. Evaporation surface was imaged by a lens through a band-path filter (650{+-}5 nm) and a double mirror system on a charge coupled device (CCD) camera. The video signals of the recorded image were connected to an image processor and converted to two-dimensional spectral radiance profiles. The surface temperatures were obtained from the spectral radiation intensity ratio of the evaporation surface and a freezing point of uranium and/or a reference light source using Planck`s law of radiation. The maximum temperature exceeded 3000 K and had saturation tendency with increasing electron beam input. The measured surface temperatures agreed with those estimated from deposition rates and data of saturated vapor pressure of uranium. (author)

  20. Self assembled temperature responsive surfaces for generation of cell patches for bone tissue engineering

    International Nuclear Information System (INIS)

    Valmikinathan, Chandra M; ChangWei; Xu Jiahua; Yu Xiaojun

    2012-01-01

    One of the major challenges in the fabrication of tissue engineered scaffolds is the ability of the scaffold to biologically mimic autograft-like tissues. One of the alternate approaches to achieve this is by the application of cell seeded scaffolds with optimal porosity and mechanical properties. However, the current approaches for seeding cells on scaffolds are not optimal in terms of seeding efficiencies, cell penetration into the scaffold and more importantly uniform distribution of cells on the scaffold. Also, recent developments in scaffold geometries to enhance surface areas, pore sizes and porosities tend to further complicate the scenario. Cell sheet-based approaches for cell seeding have demonstrated a successful approach to generate scaffold-free tissue engineering approaches. However, the method of generating the temperature responsive surface is quite challenging and requires carcinogenic reagents and gamma rays. Therefore, here, we have developed temperature responsive substrates by layer-by-layer self assembly of smart polymers. Multilayer thin films prepared from tannic acid and poly N-isopropylacrylamide were fabricated based on their electrostatic and hydrogen bonding interactions. Cell attachment and proliferation studies on these thin films showed uniform cell attachment on the substrate, matching tissue culture plates. Also, the cells could be harvested as cell patches and sheets from the scaffolds, by reducing the temperature for a short period of time, and seeded onto porous scaffolds for tissue engineering applications. An enhanced cell seeding efficiency on scaffolds was observed using the cell patch-based technique as compared to seeding cells in suspension. Owing to the already pre-existent cell–cell and cell–extracellular matrix interactions, the cell patch showed the ability to reattach rapidly onto scaffolds and showed enhanced ability to proliferate and differentiate into a bone-like matrix. (paper)

  1. Regional difference of the vertical structure of seasonal thermocline and its impact on sea surface temperature in the North Pacific

    Science.gov (United States)

    Yamaguchi, R.; Suga, T.

    2016-12-01

    Recent observational studies show that, during the warming season, a large amount of heat flux is penetrated through the base of thin mixed layer by vertical eddy diffusion, in addition to penetration of solar radiation [1]. In order to understand this heat penetration process due to vertical eddy diffusivity and its contribution to seasonal variation of sea surface temperature, we investigated the evolution of thermal stratification below the summertime thin mixed layer (i.e. evolution of seasonal thermocline) and its vertical structure in the North Pacific using high vertical resolution temperature profile observed by Argo floats. We quantified the vertical structure of seasonal thermocline as deviations from the linear structure where the vertical gradient of temperature is constant, that is, "shape anomaly". The shape anomaly is variable representing the extent of the bend of temperature profiles. We found that there are larger values of shape anomaly in the region where the seasonal sea surface temperature warming is relatively faster. To understand the regional difference of shape anomalies, we investigated the relationship between time changes in shape anomalies and net surface heat flux and surface kinetic energy flux. From May to July, the analysis indicated that, in a large part of North Pacific, there's a tendency for shape anomalies to develop strongly (weakly) under the conditions of large (small) downward net surface heat flux and small (large) downward surface kinetic energy flux. Since weak (strong) development of shape anomalies means efficient (inefficient) downward heat transport from the surface, these results suggest that the regional difference of the downward heat penetration below mixed layer is explained reasonably well by differences in surface heat forcing and surface wind forcing in a vertical one dimensional framework. [1] Hosoda et al. (2015), J. Oceanogr., 71, 541-556.

  2. The effect of clear sky radiation on crop surface temperature determined by thermal thermometry

    International Nuclear Information System (INIS)

    Svendsen, H.; Jensen, H.E.; Jensen, S.E.; Mogensen, V.O.

    1990-01-01

    By numerical integration of Planck's radiation function, a relationship between emitted radiation from a black body in the wavelength band 8–14 μm and the corresponding surface temperature was obtained. Using this relationship, an equation was developed relating the temperature error at different temperatures to the crop surface emissivity and clear sky radiation. It is concluded that the temperature error to be expected from neglect of clear sky radiation in the wavelength band 8–14μm in radiometric crop surface temperature determination is < 0.2 and 0.1 °C for crops with an emissivity > 0.96 and 0.98, respectively, for a leaf temperature range from 0 to 30°C

  3. LOW-TEMPERATURE SURFACE HARDENING FOR DIAMOND TOOLS

    Directory of Open Access Journals (Sweden)

    A. A. Shmatov

    2009-01-01

    Full Text Available The structure and properties of cutting diamond tools subjected to thermo-hydro-chemical treatment are examined in the paper. The process involves a chemical treatment of tools in a specially prepared aqueous suspension of oxides Ti, Mo and other ingredients and subsequent heat treatment (minimal process temperature 130 °C. Thermo-hydro-chemical method permits to increase a wear resistance of cutting diamond tools by the factor of 1.3–4.0 in comparison with traditional one.

  4. The Use of Satellite Data to Relate Waterbody Surface Area and Temperature to Greenhouse Gas Emissions Across a Subarctic Landscape

    Science.gov (United States)

    Herrick, C.; Palace, M. W.; Wik, M.; Burke, S. A.; Varner, R. K.

    2017-12-01

    High latitude lakes and ponds are significant sources of methane (CH4) and carbon dioxide (CO2) emission. Increased near-surface air temperature has linked these water bodies to large increases in methane emissions due to longer ice-free seasons, impacting climate change and further changing air temperature as a feedback mechanism. The impacts of changes in lake surface temperatures cannot be assessed until we know more about the baseline mechanistic biogeochemical controls that influence these emissions. Using a combination of image-based atmospheric corrections and image fusion models, thermal data from Landsat and MODIS satellites were used to characterize the temperature regimes of artic lakes in northern Sweden. This analysis provides insight into the temporal attributes of individual lakes in regard to temperature shifts and variability, as well as provides a rich temporal dataset where in situ temperature data is unavailable. Field-based measurements of temperature and associated methane release were used for calibration and correlation. This enabled the creation of emissions estimates over the broader pan-arctic landscape, including inter-seasonal and inter-annual variabilities. The result is a multi-year snapshot of temperature and emissions, allowing for future estimates of greenhouse gas emissions.

  5. Control of surface temperature of an aluminum alloy billet by air flow during a heating process at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young [KITECH, Cheonan (Korea, Republic of); Park, Joon Hong [Dong-A University, Busan (Korea, Republic of)

    2016-06-15

    The procedure of semi-solid forming is composed of heating a billet, forming, compression holding and ejecting step. There are several methods to heat a billet during semi-solid forming process such as electric heating and induction heating. Usually in semi-solid forming process, induction heating has been adopted to achieve more uniform temperature of semi-solid material. Although induction heating is better method than any others, however, there is still difference of temperature between internal part and surface part of semi-solid material. Worse yet, in case of high liquid fraction of semi-solid material, liquid of the billet will flow down though solid of the billet still remains, which is very difficult to handle. In the present study, induction heating of the billet during thixoforging process with forced surface cooling has been performed to obtain more uniform distribution of temperature, microstructure and shape of the billet. Distribution of temperature of the billets was measured and compared with that of conventional distribution of temperature. Microscopic and macroscopic aspects of the billets were discussed according to location of the measuring points. By this new induction heating method, not only temperature distributions over the whole billet become uniform, but also control of temperature distribution between inside and outside part of the billet is possible as user's experimental intentions,.

  6. Reassessment of urbanization effect on surface air temperature trends at an urban station of North China

    Science.gov (United States)

    Bian, Tao; Ren, Guoyu

    2017-11-01

    Based on a homogenized data set of monthly mean temperature, minimum temperature, and maximum temperature at Shijiazhuang City Meteorological Station (Shijiazhuang station) and four rural meteorological stations selected applying a more sophisticated methodology, we reanalyzed the urbanization effects on annual, seasonal, and monthly mean surface air temperature (SAT) trends for updated time period 1960-2012 at the typical urban station in North China. The results showed that (1) urbanization effects on the long-term trends of annual mean SAT, minimum SAT, and diurnal temperature range (DTR) in the last 53 years reached 0.25, 0.47, and - 0.50 °C/decade, respectively, all statistically significant at the 0.001 confidence level, with the contributions from urbanization effects to the overall long-term trends reaching 67.8, 78.6, and 100%, respectively; (2) the urbanization effects on the trends of seasonal mean SAT, minimum SAT, and DTR were also large and statistically highly significant. Except for November and December, the urbanization effects on monthly mean SAT, minimum SAT, and DTR were also all statistically significant at the 0.05 confidence level; and (3) the annual, seasonal, and monthly mean maximum SAT series at the urban station registered a generally weaker and non-significant urbanization effect. The updated analysis evidenced that our previous work for this same urban station had underestimated the urbanization effect and its contribution to the overall changes in the SAT series. Many similar urban stations were being included in the current national and regional SAT data sets, and the results of this paper further indicated the importance and urgency for paying more attention to the urbanization bias in the monitoring and detection of global and regional SAT change based on the data sets.

  7. A 65--70 year oscillation in observed surface temperatures

    International Nuclear Information System (INIS)

    Schlesinger, M.E.; Ramankutty, N.

    1994-01-01

    There are three possible sources for the 65--70-year ''global'' oscillation: (1) random forcing of the ocean by the atmosphere, such as by white noise; (2) external oscillatory forcing of the climate system, such as by a variation in the solar irradiance; and (3) an internal oscillation of the atmosphere-ocean system. It is unlikely that putative variations in solar irradiance are the source of the oscillation because solar forcing should generate a global response, but the oscillation is not global. It is also unlikely that white-noise forcing is the source of the oscillation because such forcing should generate an oceanwide response, but the oscillation is not panoceanic. Consequently, the most probable cause of the oscillation is an internal oscillation of the atmosphere-ocean system. This conclusion is supported by a growing body of observational evidence and coupled atmosphere/ocean general circulation model simulation results. Comparison of the regional and global-mean temperature changes caused by the oscillation with those induced by GHG + ASA forcing shows that the rapid rise in global-mean temperature between about 1908 and 1946, and the subsequent reversal of this warming until about 1965 were the result of the oscillation. In the North Atlantic and North American regions, the domination of the GHG + ASA-induced warming by the oscillation has obscured and confounded detection of this warming

  8. Improving representation of canopy temperatures for modeling subcanopy incoming longwave radiation to the snow surface

    Science.gov (United States)

    Webster, Clare; Rutter, Nick; Jonas, Tobias

    2017-09-01

    A comprehensive analysis of canopy surface temperatures was conducted around a small and large gap at a forested alpine site in the Swiss Alps during the 2015 and 2016 snowmelt seasons (March-April). Canopy surface temperatures within the small gap were within 2-3°C of measured reference air temperature. Vertical and horizontal variations in canopy surface temperatures were greatest around the large gap, varying up to 18°C above measured reference air temperature during clear-sky days. Nighttime canopy surface temperatures around the study site were up to 3°C cooler than reference air temperature. These measurements were used to develop a simple parameterization for correcting reference air temperature for elevated canopy surface temperatures during (1) nighttime conditions (subcanopy shortwave radiation is 0 W m-2) and (2) periods of increased subcanopy shortwave radiation >400 W m-2 representing penetration of shortwave radiation through the canopy. Subcanopy shortwave and longwave radiation collected at a single point in the subcanopy over a 24 h clear-sky period was used to calculate a nighttime bulk offset of 3°C for scenario 1 and develop a multiple linear regression model for scenario 2 using reference air temperature and subcanopy shortwave radiation to predict canopy surface temperature with a root-mean-square error (RMSE) of 0.7°C. Outside of these two scenarios, reference air temperature was used to predict subcanopy incoming longwave radiation. Modeling at 20 radiometer locations throughout two snowmelt seasons using these parameterizations reduced the mean bias and RMSE to below 10 W m s-2 at all locations.

  9. Ocular surface temperature in patients with evaporative and aqueous-deficient dry eyes: a thermographic approach.

    Science.gov (United States)

    Matteoli, S; Favuzza, E; Mazzantini, L; Aragona, P; Cappelli, S; Corvi, A; Mencucci, R

    2017-07-26

    In recent decades infrared thermography (IRT) has facilitated accurate quantitative measurements of the ocular surface temperature (OST), applying a non-invasive procedure. The objective of this work was to develop a procedure based on IRT, which allows characterizing of the cooling of the ocular surface of patients suffering from dry eye syndrome, and distinguishing among patients suffering from aqueous deficient dry eye (ADDE) and evaporative dry eyes (EDE). All patients examined (34 females and 4 males, 23-84 years) were divided into two groups according to their Schirmer I result (⩽ 7 mm for ADDE and  >  7 mm for EDE), and the OST was recorded for 7 s at 30 Hz. For each acquisition, the temperatures of the central cornea (CC) as well as those of both temporal and nasal canthi were investigated. Findings showed that the maximum temperature variation (up to 0.75  ±  0.29 °C) was at the CC for both groups. Furthermore, patients suffering from EDE tended to have a higher initial OST than those with ADDE, explained by the greater quantity of the tear film, evenly distributed over the entire ocular surface, keeping the OST higher initially. Results also showed that EDE patients had an average cooling rate higher than those suffering from ADDE, confirming the excessive evaporation of the tear film. Ocular thermography paves the way to become an effective tool for differentiating between the two different etiologies of dry eye syndrome.

  10. Low temperature surface hardening of stainless steel; the role of plastic deformation

    DEFF Research Database (Denmark)

    Bottoli, Federico; Jespersen, Freja Nygaard; Hattel, Jesper Henri

    2016-01-01

    : - plastic deformation of metastable austenitic stainless steels leads to the development of strain-induced martensite, which compromises the uniformity and the homogeneity of the expanded austenite zone. - during low temperature surface engineering composition and stress profiles develop. On numerical......Thermochemical surface engineering by nitriding of austenitic stainless steel transforms the surface zone into expanded austenite, which improves the wear resistance of the stainless steel while preserving the stainless behavior. As a consequence of the thermochemical surface engineering, huge...

  11. Negative feedback mechanism for the long-term stabilization of earth's surface temperature

    International Nuclear Information System (INIS)

    Walker, J.C.G.; Hays, P.B.; Kasting, J.F.

    1981-01-01

    We suggest that the partial pressure of carbon dioxide in the atmosphere is buffered, over geological time scales, by a negative feedback mechanism in which the rate of weathering of silicate minerals (followed by deposition of carbonate minerals) depends on surface temperature, and surface temperature, in turn, depends on carbon dioxide partial pressure through the green effect. Although the quantitative details of this mechanism are speculative, it appears able partially to stabilize earth's surface temperature against the steady increase of solar luminosity believed to have occured since the origin of the solar system

  12. Does quality control matter? Surface urban heat island intensity variations estimated by satellite-derived land surface temperature products

    Science.gov (United States)

    Lai, Jiameng; Zhan, Wenfeng; Huang, Fan; Quan, Jinling; Hu, Leiqiu; Gao, Lun; Ju, Weimin

    2018-05-01

    The temporally regular and spatially comprehensive monitoring of surface urban heat islands (SUHIs) have been extremely difficult, until the advent of satellite-based land surface temperature (LST) products. However, these LST products have relatively higher errors compared to in situ measurements. This has resulted in comparatively inaccurate estimations of SUHI indicators and, consequently, may have distorted interpretations of SUHIs. Although reports have shown that LST qualities are important for SUHI interpretations, systematic investigations of the response of SUHI indicators to LST qualities across cities with dissimilar bioclimates are rare. To address this issue, we chose eighty-six major cities across mainland China and analyzed SUHI intensity (SUHII) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) LST data. The LST-based SUHII differences due to inclusion or exclusion of MODIS quality control (QC) flags (i.e., ΔSUHII) were evaluated. Our major findings included, but are not limited to, the following four aspects: (1) SUHIIs can be significantly impacted by MODIS QC flags, and the associated QC-induced ΔSUHIIs generally accounted for 24.3% (29.9%) of the total SUHII value during the day (night); (2) the ΔSUHIIs differed between seasons, with considerable differences between transitional (spring and autumn) and extreme (summer and winter) seasons; (3) significant discrepancies also appeared among cities located in northern and southern regions, with northern cities often possessing higher annual mean ΔSUHIIs. The internal variations of ΔSUHIIs within individual cities also showed high heterogeneity, with ΔSUHII variations that generally exceeded 5.0 K (3.0 K) in northern (southern) cities; (4) ΔSUHIIs were negatively related to SUHIIs and cloud cover percentages (mostly in transitional seasons). No significant relationship was found in the extreme seasons. Our findings highlight the need to be extremely cautious when using LST

  13. Black Sea impact on its west-coast land surface temperature

    Science.gov (United States)

    Cheval, Sorin; Constantin, Sorin

    2018-03-01

    This study investigates the Black Sea influence on the thermal characteristics of its western hinterland based on satellite imagery acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS). The marine impact on the land surface temperature (LST) values is detected at daily, seasonal and annual time scales, and a strong linkage with the land cover is demonstrated. The remote sensing products used within the study supply LST data with complete areal coverage during clear sky conditions at 1-km spatial resolution, which is appropriate for climate studies. The sea influence is significant up to 4-5 km, by daytime, while the nighttime influence is very strong in the first 1-2 km, and it gradually decreases westward. Excepting the winter, the daytime temperature increases towards the plateau with the distance from the sea, e.g. with a gradient of 0.9 °C/km in the first 5 km in spring or with 0.7 °C/km in summer. By nighttime, the sea water usually remains warmer than the contiguous land triggering higher LST values in the immediate proximity of the coastline in all seasons, e.g. mean summer LST is 19.0 °C for the 1-km buffer, 16.6 °C for the 5-km buffer and 16.0 °C for the 10-km buffer. The results confirm a strong relationship between the land cover and thermal regime in the western hinterland of the Black Sea coast. The satellite-derived LST and air temperature values recorded at the meteorological stations are highly correlated for similar locations, but the marine influence propagates differently, pledging for distinct analysis. Identified anomalies in the general observed trends are investigated in correlation with sea surface temperature dynamics in the coastal area.

  14. Optimal Experimental Design of Borehole Locations for Bayesian Inference of Past Ice Sheet Surface Temperatures

    Science.gov (United States)

    Davis, A. D.; Huan, X.; Heimbach, P.; Marzouk, Y.

    2017-12-01

    Borehole data are essential for calibrating ice sheet models. However, field expeditions for acquiring borehole data are often time-consuming, expensive, and dangerous. It is thus essential to plan the best sampling locations that maximize the value of data while minimizing costs and risks. We present an uncertainty quantification (UQ) workflow based on rigorous probability framework to achieve these objectives. First, we employ an optimal experimental design (OED) procedure to compute borehole locations that yield the highest expected information gain. We take into account practical considerations of location accessibility (e.g., proximity to research sites, terrain, and ice velocity may affect feasibility of drilling) and robustness (e.g., real-time constraints such as weather may force researchers to drill at sub-optimal locations near those originally planned), by incorporating a penalty reflecting accessibility as well as sensitivity to deviations from the optimal locations. Next, we extract vertical temperature profiles from these boreholes and formulate a Bayesian inverse problem to reconstruct past surface temperatures. Using a model of temperature advection/diffusion, the top boundary condition (corresponding to surface temperatures) is calibrated via efficient Markov chain Monte Carlo (MCMC). The overall procedure can then be iterated to choose new optimal borehole locations for the next expeditions.Through this work, we demonstrate powerful UQ methods for designing experiments, calibrating models, making predictions, and assessing sensitivity--all performed under an uncertain environment. We develop a theoretical framework as well as practical software within an intuitive workflow, and illustrate their usefulness for combining data and models for environmental and climate research.

  15. The surface temperature effect on the dissociative sticking of N2 on Fe(111)

    DEFF Research Database (Denmark)

    Henriksen, Niels Engholm; Hansen, Flemming Yssing; Billing, Gert Due

    1995-01-01

    We present the first realistic calculation of the surface temperature effect on the dissociative sticking probability of molecular nitrogen on Fe(111). Extensive quantum dynamical calculations show that, depending on the impact point in the unit cell, the sticking probabilities can increase as well...... as decrease as a function of the surface temperature. The magnitude of the temperature effect on randomly chosen impact points is comparable with the experimental observation. Since only a small fraction of the impacts give a significant contribution to the sticking and the alternating temperature effect...

  16. Effect of machining on the deformability of steel in surface-active medium at lower temperatures

    International Nuclear Information System (INIS)

    Gusti, E.Ya.; Babej, Yu.I.

    1977-01-01

    The effect of some machining methods of carbon steel, chromium steel, and chromium nickel steel, and that of low temperatures on the principle characteristics of formability during impact bending in air and a surface-active environment have been studied. The temperature decrease from the ambient to -80 deg is shown to reduce steel formability as evaluated by deflection (f) and to increase the forming force. The variation of these characteristics with lowering temperature, however, is greatly affected by machining process conditions. The FRHT (Friction-Hardening Treatment) on the white layer assures minimum ductility losses, and increases steel strength at low temperatures both in air and in the surface-active environment

  17. Reconnoitering the effect of shallow groundwater on land surface temperature and surface energy balance using MODIS and SEBS

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2012-07-01

    Full Text Available The possibility of observing shallow groundwater depth and areal extent using satellite measurements can support groundwater models and vast irrigation systems management. Moreover, these measurements can help to include the effect of shallow groundwater on surface energy balance within land surface models and climate studies, which broadens the methods that yield more reliable and informative results. To examine the capacity of MODIS in detecting the effect of shallow groundwater on land surface temperature and the surface energy balance in an area within Al-Balikh River basin in northern Syria, we studied the interrelationship between in-situ measured water table depths and land surface temperatures measured by MODIS. We, also, used the Surface Energy Balance System (SEBS to calculate surface energy fluxes, evaporative fraction and daily evaporation, and inspected their relationships with water table depths. We found out that the daytime temperature increased while the nighttime temperature decreased when the depth of the water table increased. And, when the water table depth increased, net radiation, latent and ground heat fluxes, evaporative fraction and daily evaporation decreased, while sensible heat flux increased. This concords with the findings of a companion paper (Alkhaier et al., 2012. The observed clear relationships were the result of meeting both conditions that were concluded in the companion paper, i.e. high potential evaporation and big contrast in day-night temperature. Moreover, the prevailing conditions in this study area helped SEBS to yield accurate estimates. Under bare soil conditions and under the prevailing weather conditions, we conclude that MODIS is suitable for detecting the effect of shallow groundwater because it has proper imaging times and adequate sensor accuracy; nevertheless, its coarse spatial resolution is disadvantageous.

  18. Paleoclimatic reconstructions in western Canada from borehole temperature logs: surface air temperature forcing and groundwater flow

    Czech Academy of Sciences Publication Activity Database

    Majorowicz, J.; Grasby, S. E.; Ferguson, G.; Šafanda, Jan; Skinner, W.

    2006-01-01

    Roč. 2, č. 1 (2006), s. 1-10 ISSN 1814-9324 Institutional research plan: CEZ:AV0Z30120515 Keywords : palaeoclimatic reconstructions * Canada * borehole temperatures Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  19. Measurement of temperature and pressure on the surface of a blunt cone using FBG sensor in hypersonic wind tunnel

    Science.gov (United States)

    Prasad, A. S. Guru; Sharath, U.; Nagarjun, V.; Hegde, G. M.; Asokan, S.

    2013-09-01

    Measurement of temperature and pressure exerted on the leeward surface of a blunt cone specimen has been demonstrated in the present work in a hypersonic wind tunnel using fiber Bragg grating (FBG) sensors. The experiments were conducted on a 30° apex-angle blunt cone with 51 mm base diameter at wind flow speeds of Mach 6.5 and 8.35 in a 300 mm hypersonic wind tunnel of Indian Institute of Science, Bangalore. A special pressure insensitive temperature sensor probe along with the conventional bare FBG sensors was used for explicit temperature and aerodynamic pressure measurement respectively on the leeward surface of the specimen. computational fluid dynamics (CFD) simulation of the flow field around the blunt cone specimen has also been carried out to obtain the temperature and pressure at conditions analogous to experiments. The results obtained from FBG sensors and the CFD simulations are found to be in good agreement with each other.

  20. Measurement of temperature and pressure on the surface of a blunt cone using FBG sensor in hypersonic wind tunnel

    International Nuclear Information System (INIS)

    Guru Prasad, A S; Sharath, U; Asokan, S; Nagarjun, V; Hegde, G M

    2013-01-01

    Measurement of temperature and pressure exerted on the leeward surface of a blunt cone specimen has been demonstrated in the present work in a hypersonic wind tunnel using fiber Bragg grating (FBG) sensors. The experiments were conducted on a 30° apex-angle blunt cone with 51 mm base diameter at wind flow speeds of Mach 6.5 and 8.35 in a 300 mm hypersonic wind tunnel of Indian Institute of Science, Bangalore. A special pressure insensitive temperature sensor probe along with the conventional bare FBG sensors was used for explicit temperature and aerodynamic pressure measurement respectively on the leeward surface of the specimen. computational fluid dynamics (CFD) simulation of the flow field around the blunt cone specimen has also been carried out to obtain the temperature and pressure at conditions analogous to experiments. The results obtained from FBG sensors and the CFD simulations are found to be in good agreement with each other. (paper)

  1. Optimal estimation of sea surface temperature from AMSR-E

    DEFF Research Database (Denmark)

    Nielsen-Englyst, Pia; Høyer, Jacob L.; Pedersen, Leif Toudal

    2018-01-01

    setup. In addition, updating the forward model, using a multivariate regression model is shown to improve the capability of the forward model to reproduce the observations. The average sensitivity of the OE retrieval is 0.5 and shows a latitudinal dependency with smaller sensitivity for cold waters...... and larger sensitivity for warmer waters. The OE SSTs are evaluated against drifting buoy measurements during 2010. The results show an average difference of 0.02 K with a standard deviation of 0.47 K when considering the 64% matchups, where the simulated and observed brightness temperatures are most...... considering the best 62% of retrievals. The satellite versus in situ discrepancies are highest in the dynamic oceanic regions due to the large satellite footprint size and the associated sampling effects. Uncertainty estimates are available for all retrievals and have been validated to be accurate. They can...

  2. Newly devised infrared radiometer (ERI type IR ground scanner) and the surface temperature of the Mihara crater, O-shima

    Energy Technology Data Exchange (ETDEWEB)

    Shimozuru, D [Earthquake Res. Inst., Univ. of Tokyo; Kagiyama, T

    1976-10-01

    The infrared radiometer, a remote sensing tool, can be successfully used to measure the surface temperature of a volcanic or geothermal area. Many of these devices are available commercially for industrial use but their application to volcano observations is limited due to a wide field of view which prohibits detailed examination of specific points. A commercial radiometer was mounted on a balloon theodolite with an electrically driven rotating base. A telescope was attached to the radiometer to permit monitoring of the field of view. Radiometer output can be recorded either on a magnetic tape data recorder or a strip chart recorder. The device is also useful for continuous monitoring of the temperature of a vent or fumarole. The observed temperatures are dependent upon the wave length of actual spatial temperature distribution, the field of view and the scanning speed. Detailed information of both a theoretical and an experimental nature is provided. The improved radiometer was utilized to observe surface temperature in the caldera of Miharayama, Oshima in March, 1976. It was found that the vent temperature was markedly lower than had previously been recorded, as was the average surface temperature.

  3. [Study on Hollow Brick Wall's Surface Temperature with Infrared Thermal Imaging Method].

    Science.gov (United States)

    Tang, Ming-fang; Yin, Yi-hua

    2015-05-01

    To address the characteristic of uneven surface temperature of hollow brick wall, the present research adopts soft wares of both ThermaCAM P20 and ThermaCAM Reporter to test the application of infrared thermal image technique in measuring surface temperature of hollow brick wall, and further analyzes the thermal characteristics of hollow brick wall, and building material's impact on surface temperature distribution including hollow brick, masonry mortar, and so on. The research selects the construction site of a three-story-high residential, carries out the heat transfer experiment, and further examines the exterior wall constructed by 3 different hollow bricks including sintering shale hollow brick, masonry mortar and brick masonry. Infrared thermal image maps are collected, including 3 kinds of sintering shale hollow brick walls under indoor heating in winter; and temperature data of wall surface, and uniformity and frequency distribution are also collected for comparative analysis between 2 hollow bricks and 2 kinds of mortar masonry. The results show that improving heat preservation of hollow brick aid masonry mortar can effectively improve inner wall surface temperature and indoor thermal environment; non-uniformity of surface temperature decreases from 0. 6 to 0. 4 °C , and surface temperature frequency distribution changes from the asymmetric distribution into a normal distribution under the condition that energy-saving sintering shale hollow brick wall is constructed by thermal mortar replacing cement mortar masonry; frequency of average temperature increases as uniformity of surface temperature increases. This research provides a certain basis for promotion and optimization of hollow brick wall's thermal function.

  4. Corneal surface temperature change as the mode of stimulation of the non-contact corneal aesthesiometer.

    Science.gov (United States)

    Murphy, P J; Morgan, P B; Patel, S; Marshall, J

    1999-05-01

    The non-contact corneal aesthesiometer (NCCA) assesses corneal sensitivity by using a controlled pulse of air, directed at the corneal surface. The purpose of this paper was to investigate whether corneal surface temperature change was a component in the mode of stimulation. Thermocouple experiment: A simple model corneal surface was developed that was composed of a moistened circle of filter paper placed on a thermocouple and mounted on a glass slide. The temperature change produced by different stimulus pressures was measured for five different ambient temperatures. Thermal camera experiment: Using a thermal camera, the corneal surface temperature change was measured in nine young, healthy subjects after exposure to different stimulus air pulses. Pulse duration was set at 0.9 s but was varied in pressure from 0.5 to 3.5 millibars. Thermocouple experiment: An immediate drop in temperature was detected by the thermocouple as soon as the air flow was incident on the filter paper. A greater temperature change was produced by increasing the pressure of the incident air flow. A relationship was found and a calibration curve plotted. Thermal camera experiment: For each subject, a drop in surface temperature was detected at each stimulus pressure. Furthermore, as the stimulus pressure increased, the induced reduction in temperature also increased. A relationship was found and a calibration curve plotted. The NCCA air-pulse stimulus was capable of producing a localized temperature change on the corneal surface. The principal mode of corneal nerve stimulation, by the NCCA air pulse, was the rate of temperature change of the corneal surface.

  5. Surface temperature evolution and the location of maximum and average surface temperature of a lithium-ion pouch cell under variable load profiles

    DEFF Research Database (Denmark)

    Goutam, Shovon; Timmermans, Jean-Marc; Omar, Noshin

    2014-01-01

    This experimental work attempts to determine the surface temperature evolution of large (20 Ah-rated capacity) commercial Lithium-Ion pouch cells for the application of rechargeable energy storage of plug in hybrid electric vehicles and electric vehicles. The cathode of the cells is nickel...

  6. Sea Surface Temperature Modeling using Radial Basis Function Networks With a Dynamically Weighted Particle Filter

    KAUST Repository

    Ryu, Duchwan

    2013-03-01

    The sea surface temperature (SST) is an important factor of the earth climate system. A deep understanding of SST is essential for climate monitoring and prediction. In general, SST follows a nonlinear pattern in both time and location and can be modeled by a dynamic system which changes with time and location. In this article, we propose a radial basis function network-based dynamic model which is able to catch the nonlinearity of the data and propose to use the dynamically weighted particle filter to estimate the parameters of the dynamic model. We analyze the SST observed in the Caribbean Islands area after a hurricane using the proposed dynamic model. Comparing to the traditional grid-based approach that requires a supercomputer due to its high computational demand, our approach requires much less CPU time and makes real-time forecasting of SST doable on a personal computer. Supplementary materials for this article are available online. © 2013 American Statistical Association.

  7. Estimating surface turbulent heat fluxes from land surface temperature and soil moisture using the particle batch smoother

    Science.gov (United States)

    Lu, Yang; Dong, Jianzhi; Steele-Dunne, Susan; van de Giesen, Nick

    2016-04-01

    This study is focused on estimating surface sensible and latent heat fluxes from land surface temperature (LST) time series and soil moisture observations. Surface turbulent heat fluxes interact with the overlying atmosphere and play a crucial role in meteorology, hydrology and other climate-related fields, but in-situ measurements are costly and difficult. It has been demonstrated that the time series of LST contains information of energy partitioning and that surface turbulent heat fluxes can be determined from assimilation of LST. These studies are mainly based on two assumptions: (1) a monthly value of bulk heat transfer coefficient under neutral conditions (CHN) which scales the sum of the fluxes, and (2) an evaporation fraction (EF) which stays constant during the near-peak hours of the day. Previous studies have applied variational and ensemble approaches to this problem. Here the newly developed particle batch smoother (PBS) algorithm is adopted to test its capability in this application. The PBS can be seen as an extension of the standard particle filter (PF) in which the states and parameters within a fix window are updated in a batch using all observations in the window. The aim of this study is two-fold. First, the PBS is used to assimilate only LST time series into the force-restore model to estimate fluxes. Second, a simple soil water transfer scheme is introduced to evaluate the benefit of assimilating soil moisture observations simultaneously. The experiments are implemented using the First ISLSCP (International Satellite Land Surface Climatology Project) (FIFE) data. It is shown that the restored LST time series using PBS agrees very well with observations, and that assimilating LST significantly improved the flux estimation at both daily and half-hourly time scales. When soil moisture is introduced to further constrain EF, the accuracy of estimated EF is greatly improved. Furthermore, the RMSEs of retrieved fluxes are effectively reduced at both

  8. Low-temperature α-alumina thin film growth: ab initio studies of Al adatom surface migration

    International Nuclear Information System (INIS)

    Wallin, E; Helmersson, U; Muenger, E P; Chirita, V

    2009-01-01

    Investigations of activation energy barriers for Al surface hopping on α-Al 2 O 3 (0 0 0 1) surfaces have been carried out by means of first-principles density functional theory calculations and the nudged elastic band method. Results show that surface diffusion on the (most stable) Al-terminated surface is relatively fast with an energy barrier of 0.75 eV, whereas Al hopping on the O-terminated surface is slower, with barriers for jumps from the two metastable positions existing on this surface to the stable site of 0.31 and 0.99 eV. Based on this study and on the literature, the governing mechanisms during low-temperature α-alumina thin film growth are summarized and discussed. Our results support suggestions made in some previous experimental studies, pointing out that limited surface diffusivity is not the main obstacle for α-alumina growth at low-to-moderate temperatures, and that other effects should primarily be considered when designing novel processes for low-temperature α-alumina deposition.

  9. Coherent changes of wintertime surface air temperatures over North Asia and North America.

    Science.gov (United States)

    Yu, Bin; Lin, Hai

    2018-03-29

    The surface temperature variance and its potential change with global warming are most prominent in winter over Northern Hemisphere mid-high latitudes. Consistent wintertime surface temperature variability has been observed over large areas in Eurasia and North America on a broad range of time scales. However, it remains a challenge to quantify where and how the coherent change of temperature anomalies occur over the two continents. Here we demonstrate the coherent change of wintertime surface temperature anomalies over North Asia and the central-eastern parts of North America for the period from 1951 to 2015. This is supported by the results from the empirical orthogonal function analysis of surface temperature and temperature trend anomalies over the Northern Hemisphere extratropical lands and the timeseries analysis of the regional averaged temperature anomalies over North Asia and the Great Plains and Great Lakes. The Asian-Bering-North American (ABNA) teleconnection provides a pathway to connect the regional temperature anomalies over the two continents. The ABNA is also responsible for the decadal variation of the temperature relationship between North Asia and North America.

  10. Airborne-Measured Spatially-Averaged Temperature and Moisture Turbulent Structure Parameters Over a Heterogeneous Surface

    Science.gov (United States)

    Platis, Andreas; Martinez, Daniel; Bange, Jens

    2014-05-01

    Turbulent structure parameters of temperature and humidity can be derived from scintillometer measurements along horizontal paths of several 100 m to several 10 km. These parameters can be very useful to estimate the vertical turbulent heat fluxes at the surface (applying MOST). However, there are many assumptions required by this method which can be checked using in situ data, e.g. 1) Were CT2 and CQ2 correctly derived from the initial CN2 scintillometer data (structure parameter of density fluctuations or refraction index, respectively)? 2) What is the influence of the surround hetereogeneous surface regarding its footprint and the weighted averaging effect of the scintillometer method 3) Does MOST provide the correct turbulent fluxes from scintillometer data. To check these issues, in situ data from low-level flight measurements are well suited, since research aircraft cover horizontal distances in very short time (Taylor's hypothesis of a frozen turbulence structure can be applyed very likely). From airborne-measured time series the spatial series are calculated and then their structure functions that finally provide the structure parameters. The influence of the heterogeneous surface can be controlled by the definition of certain moving-average window sizes. A very useful instrument for this task are UAVs since they can fly very low and maintain altitude very precisely. However, the data base of such unmanned operations is still quite thin. So in this contribution we want to present turbulence data obtained with the Helipod, a turbulence probe hanging below a manned helicopter. The structure parameters of temperature and moisture, CT2 and CQ2, in the lower convective boundary layer were derived from data measured using the Helipod in 2003. The measurements were carried out during the LITFASS03 campaign over a heterogeneous land surface around the boundary-layer field site of the Lindenberg Meteorological Observatory-Richard-Aßmann-Observatory (MOL) of the

  11. Comparison of Conductor-Temperature Calculations Based on Different Radial-Position-Temperature Detections for High-Voltage Power Cable

    Directory of Open Access Journals (Sweden)

    Lin Yang

    2018-01-01

    Full Text Available In this paper, the calculation of the conductor temperature is related to the temperature sensor position in high-voltage power cables and four thermal circuits—based on the temperatures of insulation shield, the center of waterproof compound, the aluminum sheath, and the jacket surface are established to calculate the conductor temperature. To examine the effectiveness of conductor temperature calculations, simulation models based on flow characteristics of the air gap between the waterproof compound and the aluminum are built up, and thermocouples are placed at the four radial positions in a 110 kV cross-linked polyethylene (XLPE insulated power cable to measure the temperatures of four positions. In measurements, six cases of current heating test under three laying environments, such as duct, water, and backfilled soil were carried out. Both errors of the conductor temperature calculation and the simulation based on the temperature of insulation shield were significantly smaller than others under all laying environments. It is the uncertainty of the thermal resistivity, together with the difference of the initial temperature of each radial position by the solar radiation, which led to the above results. The thermal capacitance of the air has little impact on errors. The thermal resistance of the air gap is the largest error source. Compromising the temperature-estimation accuracy and the insulation-damage risk, the waterproof compound is the recommended sensor position to improve the accuracy of conductor-temperature calculation. When the thermal resistances were calculated correctly, the aluminum sheath is also the recommended sensor position besides the waterproof compound.

  12. Water dissociation on Ni(100) and Ni(111): Effect of surface temperature on reactivity

    International Nuclear Information System (INIS)

    Seenivasan, H.; Tiwari, Ashwani K.

    2013-01-01

    Water adsorption and dissociation on Ni(100) and Ni(111) surfaces are studied using density functional theory calculations. Water adsorbs on top site on both the surfaces, while H and OH adsorb on four fold hollow and three fold hollow (fcc) sites on Ni(100) and Ni(111), respectively. Transition states (TS) on both surfaces are identified using climbing image-nudged elastic band method. It is found that the barrier to dissociation on Ni(100) surface is slightly lower than that on Ni(111) surface. Dissociation on both the surfaces is exothermic, while the exothermicity on Ni(100) is large. To study the effect of lattice motion on the energy barrier, TS calculations are performed for various values of Q (lattice atom coordinate along the surface normal) and the change in the barrier height and position is determined. Calculations show that the energy barrier to reaction decreases with increasing Q and increases with decreasing Q on both the surfaces. Dissociation probability values at different surface temperatures are computed using semi-classical approximation. Results show that the influence of surface temperature on dissociation probability on the Ni(100) is significantly larger compared to that of Ni(111). Moreover, on Ni(100), a dramatic shift in energy barrier to lower incident energy values is observed with increasing surface temperature, while the shift is smaller in the case of Ni(111)

  13. Surface chemistry of metals and their oxides in high temperature water

    International Nuclear Information System (INIS)

    Tomlinson, M.

    1975-01-01

    Examination of oxide and metal surfaces in water at high temperature by a broad spectrum of techniques is bringing understanding of corrosion product movement and alleviation of activity transport in CANDU-type reactor primary coolant circuits. (Author)

  14. IceBridge NSERC L1B Geolocated Meteorologic and Surface Temperature Data

    Data.gov (United States)

    National Aeronautics and Space Administration — The IceBridge National Suborbital Education & Research Center (NSERC) L1B Geolocated Meteorologic and Surface Temperature (IAMET1B) data set is a collection of...

  15. IceBridge NSERC L1B Geolocated Meteorologic and Surface Temperature Data, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — The IceBridge National Suborbital Education & Research Center (NSERC) L1B Geolocated Meteorologic and Surface Temperature (IAMET1B) data set is a collection of...

  16. 14 km Sea Surface Temperature for North America, 1986 - present (NODC Accession 0099042)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This product presents local sea surface temperatures (degrees C). It is a composite gridded-image derived from 8-km resolution SST observations collected by Advanced...

  17. Temperature, All Surface, NOAA POES AVHRR, LAC, 0.0125 degrees, West US, Daytime

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch provides surface temperature products derived from NOAA's Polar Operational Environmental Satellites (POES). This data is provided at high resolution...

  18. The lowering of sea surface temperature in the east central Arabian sea associated with a cyclone

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, V.S.N.; Rao, D.P.; Sastry, J.S.

    An analysis of thermal Structure in the East Central Arabian Sea associated with a moderate cyclone is presented. The heat storage and the heat budget components have been computed. Under the influence of the cyclone the Sea Surface Temperature (SST...

  19. Monthly version of HadISST sea surface temperature state-space components

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — State-Space Decomposition of Monthly version of HadISST sea surface temperature component (1-degree). See Rayner, N. A., Parker, D. E., Horton, E. B., Folland, C....

  20. The effects of artificial surface temperature on mechanical properties and player kinematics during landing and acceleration

    Directory of Open Access Journals (Sweden)

    Laura Charalambous

    2016-09-01

    Conclusion: These findings highlight different demands placed on players due to the surface temperature and suggest a need for coaches, practitioners, and sports governing bodies to be aware of these differences.