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• A bilinear aging albedo model for asphalt pavements was calibrated from field cores. • Visible reflectance and albedo have a strong correlation for asphalt pavements. • Albedo, emissivity, and location impact radiative forcing. • Differences in thermal and optical properties affect surface temperature. Pavements contribute significantly to the development of Urban Heat Islands (UHIs). The impact of pavements on UHI depends on multiple material factors, including its thermal and optical properties. Field cores from asphalt concrete (AC) pavements from four locations in Illinois and one in Indiana, USA, were used to evaluate the optical and thermal properties of the corresponding pavements. Thermal conductivity ranged from 1.0 to 3.0 W/mK (average of 2.2 W/mK), diffusivity 0.6–2.0 mm2/s (average of 1.5 mm2/s), and heat capacity 0.7–3.0 MJ/m3K (average of 1.5 MJ/m3K), which differ significantly from values typically recommended in pavement design. The same cores were used to calibrate a simplified bilinear aging albedo model, with the asymptotic albedo and at-construction albedo being largely within the expected range of 0.10–0.20 and 0.05–0.10, respectively. The emissivity was found to be between 0.70 and 0.90, which agrees with values reported in the literature. These properties were used to evaluate the local pavement Radiative Forcing ( RF p ) and Global Warming Potential (GWP) as well as the diurnal net surface heat flux and surface temperature of the pavements. The RF p varied depending on aging albedo and emissivity, while surface temperature and net surface heat flux also depended on thermal properties. [ABSTRACT FROM AUTHOR]

Boreal forest regions are a focal point for investigations of coupled water and biogeochemical fluxes in response to wildfire disturbances, climate warming, and permafrost thaw. Soil hydraulic, physical, and thermal property measurements for mineral soils in permafrost regions are limited, despite substantial influences on cryohydrogeologic model results. This work expands mineral soil property quantification in cold regions through soil characterization from the discontinuous permafrost zone of interior Alaska, USA. Values extend beyond the range of prior measurement magnitudes in analogous regions, highlighting the importance of this data set. Rocky and silty upland soil landscape classifications and wildfire disturbance provided guiding frameworks for the sampling and analysis for potential implications for the hydrologic response to thawing permafrost. Bulk density (ρb), soil organic matter, soil‐particle size distributions (sand, silt, and gravel fractions), and soil hydraulic properties of van Genuchten parameters alpha and N had moderate evidence of differences between silty and rocky classifications. Burned and unburned sites had only moderate evidence of differences for silt fraction. Field‐saturated hydraulic conductivity (Kfs) was more variable at burned sites compared to unburned sites, which corresponded to observations of greater rooting depths at burned sites and observations of root paths in soil cores for Kfs measurement. Soil thermal properties suggested that gravel content may reduce the accuracy of commonly used estimation methods for thermal conductivity. This work provides soil parameter constraints necessary for hypothesis testing and site‐specific prediction with cryohydrogeologic models to examine controls on active layer and permafrost dynamics in upland boreal forests. Key Points: Physical and hydraulic property magnitudes in mineral soils extended beyond ranges from prior work in permafrost regions in interior AlaskaMineral soil thermal properties were substantially affected by gravel content, which is not included in common texture‐based estimationThis provides soil parameter constraints for hypothesis testing and prediction for active layer and permafrost dynamics in upland boreal forests [ABSTRACT FROM AUTHOR]

The continental lithospheric mantle plays an essential role in stabilizing continents over long geological time scales. Quantifying spatial variations in thermal and compositional properties of the mantle lithosphere is crucial to understanding its formation and its impact on continental stability; however, our understanding of these variations remains limited. Here we apply the Whole-rock Interpretive Seismic Toolbox For Ultramafic Lithologies (WISTFUL) to estimate thermal, compositional, and density variations in the continental mantle beneath the contiguous United States from MITPS_20, a joint body and surface wave tomographic inversion for V p and V s with high resolution in the shallow mantle (60–100 km). Our analysis shows lateral variations in temperature beneath the continental United States of up to 800–900 °C at 60, 80, and 100 km depth. East of the Rocky Mountains, the mantle lithosphere is generally cold (350–850 °C at 60 km), with higher temperatures (up to 1000 °C at 60 km) along the Atlantic coastal margin. By contrast, the mantle lithosphere west of the Rocky Mountains is hot (typically >1000 °C at 60 km, >1200 °C at 80–100 km), with the highest temperatures beneath Holocene volcanoes. In agreement with previous work, we find that the chemical depletion predicted by WISTFUL does not fully offset the density difference due to temperature. Extending our results using Rayleigh-Taylor instability analysis, implies the lithosphere below the United States could be undergoing oscillatory convection, in which cooling, densification, and sinking of a chemically buoyant layer alternates with reheating and rising of that layer. • MITPS_20, a continental US tomographic model, is interpreted in terms of temperature, composition, and density. • Our method predicts temperatures of 260–1430 °C, Mg# of 85–92, and density between 3230–3370 kg m−3 between 60–100 km. • Predicted compositional buoyancy of the mantle lithosphere compensates only part (40%) of the negative thermal buoyancy. [ABSTRACT FROM AUTHOR]

ABSTRACT The confluence of two US energy policy mandates, the 2012 Corporate Average Fuel Economy Standards and Renewable Fuels Standard #2, provide the opportunity to examine the possibility of high-value materials from lignin with increased depth. In this case, the desire to provide lighter, low-cost materials for automobiles to reduce fuel consumption, and to improve the economics of biorefineries for fuel production, have led to an increased interest in low-cost carbon fiber manufacture from lignin. For this review the authors provide the context of subject matter importance, a cost comparison of potential low-cost carbon fibers, a brief review of historical work, a review of more recent work, and a limited technical discussion followed by recommendations for future directions. As the available material for review is limited, the author includes many references to publicly available government documents and reviewed proceedings that are generally difficult to locate. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 713-728, 2013 [ABSTRACT FROM AUTHOR]

Abstract: This paper evaluates the solar water heating systems for the U.S. typical residential buildings, from the energetic, economic and environmental perspectives, and includes two different types of solar collectors (i.e. flat-plate and evacuated-tube solar collectors), two types of auxiliary systems (i.e. natural gas and electricity), and three different locations (i.e. Los Angeles, Atlanta, and Chicago). The performance of solar water heating systems is also compared with conventional systems that use either natural gas or electricity. The results showed that the flat-plate solar water heating systems using natural gas auxiliary heater has the best performance among all the types and at all locations. The energetic and environmental payback periods for solar water heating systems are less than half of a year, and the life cycle cost payback for solar water heating systems vary from 4 to 13 years for different cities and different configurations when using the conventional electrical water heating system in each city as the benchmark. For a representative case, i.e. flat-plate solar water heating system with natural gas auxiliary heater in Atlanta, sensitivity analysis shows that the daily hot water use has the most significant effects on energetic, environmental and economic performance. [Copyright &y& Elsevier]

In order to obtain viscosities of biodiesel fuels at a temperature range from 0 to 100°C in the steps of 10°C, DV-II+ Pro rotary viscosimeter from Brookfield Engineering Co., USA, was used and tests were performed at 20°C ambient temperature. The viscosity measurements were made on a viscosimeter at a 100 rpm constant speed with PC control. The data with the Wingather VII software from Brookfield Engineering Co., USA, were recorded in the computer at 5 second intervals. It is observed that biodiesels are similar to diesel fuels in view of the viscosity properties when the diesel fuel concentration in which biodiesel and the temperature is increased. [ABSTRACT FROM AUTHOR]

Temporal variability in the occurrence of the most extreme snowfall years, both those with abundant snowfall amounts and those lacking snowfall, was examined using a set of 440 quality-controlled, homogenous U.S. snowfall records. The frequencies with which winter-centered annual snowfall totals exceeded the 90th and 10th percentile thresholds at individual stations were calculated from 1900–01 to 2006–07 for the conterminous United States, and for 9 standard climate regions. The area-weighted conterminous U.S. results do not show a statistically significant trend in the occurrence of either high or low snowfall years for the 107-yr period, but there are regional trends. Large decreases in the frequency of low-extreme snowfall years in the west north-central and east north-central United States are balanced by large increases in the frequency of low-extreme snowfall years in the Northeast, Southeast, and Northwest. During the latter portion of the period, from 1950–51 to 2006–07, trends are much more consistent, with the United States as a whole and the central and northwest U.S. regions in particular showing significant declines in high-extreme snowfall years, and four regions showing significant increases in the frequency of low-extreme snowfall years (i.e., Northeast, Southeast, south, and Northwest). In almost all regions of the United States, temperature during November–March is more highly correlated than precipitation to the occurrence of extreme snowfall years. El Niño events are strongly associated with an increase in low-extreme snowfall years over the United States as a whole, and in the northwest, northeast, and central regions. A reduction in low-extreme snowfall years in the Southwest is also associated with El Niño. The impacts of La Niña events are strongest in the south and Southeast, favoring fewer high-extreme snowfall years, and, in the case of the south, more low-extreme snowfall years occur. The Northwest also has a significant reduction in the chance of a low-extreme snowfall year during La Niña. A combination of trends in temperature in the United States and changes in the frequency of ENSO modes influences the frequency of extreme snowfall years in the United States. [ABSTRACT FROM AUTHOR]

Four different catfish oil extraction processes were used to extract oil from catfish viscera: process CF1 involved a mixture of ground catfish viscera and water, no heat treatment, and centrifugation; process CF2 involved ground catfish viscera (no added water), heat treatment, and centrifugation; process CF3 involved a mixture of ground catfish viscera and water, heat treatment, and centrifugation; process CF4 involved ground catfish viscera, enzymatic hydrolysis, and centrifugation. Chemical and physical properties of the resulting of catfish oils were evaluated. The CF4 process recovered significantly higher amounts of crude oil from catfish viscera than the other 3 extraction methods. The CF4 oil contained a higher percent of free fatty acid and peroxide values than CF1, CF2, and CF3 oils. Oleic acid in catfish oil was the predominant fatty acid accounting for about 50% of total fatty acids. Weight loss of oils increased with increasing temperatures between 250 and 500 °C. All the catfish oil samples melted around −32 °C regardless of the extraction methods. The flow behavior index of all the oil samples was less than 1, which indicated that the catfish oils exhibited non-Newtonian fluid behavior. The apparent viscosity at −5 and 0 °C was significantly higher ( P < 0.05) than those at 5, 10, 15, 20, 25, and 30 °C. The average magnitude of activation energy for apparent viscosity of the oil was higher for CF2 than CF1, CF3, and CF4. [ABSTRACT FROM AUTHOR]

There is a need for methodology to warm open-field plots in order to study the likely effects of global warming on ecosystems in the future. Herein, we describe the development of arrays of more powerful and efficient infrared heaters with ceramic heating elements. By tilting the heaters at 45° from horizontal and combining six of them in a hexagonal array, good uniformity of warming was achieved across 3-m-diameter plots. Moreover, there do not appear to be obstacles (other than financial) to scaling to larger plots. The efficiency [ ηh (%); thermal radiation out per electrical energy in] of these heaters was higher than that of the heaters used in most previous infrared heater experiments and can be described by: ηh= 10 + 25exp(− 0.17 u), where u is wind speed at 2 m height (m s− 1). Graphs are presented to estimate operating costs from degrees of warming, two types of plant canopy, and site windiness. Four such arrays were deployed over plots of grass at Haibei, Qinghai, China and another at Cheyenne, Wyoming, USA, along with corresponding reference plots with dummy heaters. Proportional integral derivative systems with infrared thermometers to sense canopy temperatures of the heated and reference plots were used to control the heater outputs. Over month-long periods at both sites, about 75% of canopy temperature observations were within 0.5 °C of the set-point temperature differences between heated and reference plots. Electrical power consumption per 3-m-diameter plot averaged 58 and 80 kW h day− 1 for Haibei and Cheyenne, respectively. However, the desired temperature differences were set lower at Haibei (1.2 °C daytime, 1.7 °C night) than Cheyenne (1.5 °C daytime, 3.0 °C night), and Cheyenne is a windier site. Thus, we conclude that these hexagonal arrays of ceramic infrared heaters can be a successful temperature free-air-controlled enhancement (T-FACE) system for warming ecosystem field plots. [ABSTRACT FROM AUTHOR]

Habitat conditions mediate the effects of climate, so neighboring populations with differing habitat conditions may differ in their responses to climate change. We have previously observed that juvenile survival in Snake River spring/summer Chinook salmon is strongly correlated with summer temperature in some populations and with fall streamflow in others. Here, we explore potential differential responses of the viability of four of these populations to changes in streamflow and temperature that might result from climate change. First, we linked predicted changes in air temperature and precipitation from several General Circulation Models to a local hydrological model to project streamflow and air temperature under two climate-change scenarios. Then, we developed a stochastic, density-dependent life-cycle model with independent environmental effects in juvenile and ocean stages, and parameterized the model for each population. We found that mean abundance decreased 20–50% and the probability of quasi-extinction increased dramatically (from 0.1–0.4 to 0.3–0.9) for all populations in both scenarios. Differences between populations were greater in the more moderate climate scenario than in the more extreme, hot/dry scenario. Model results were relatively robust to realistic uncertainty in freshwater survival parameters in all scenarios. Our results demonstrate that detailed population models can usefully incorporate climate-change predictions, and that global warming poses a direct threat to freshwater stages in these fish, increasing their risk of extinction. Because differences in habitat may contribute to the individualistic population responses we observed, we infer that maintaining habitat diversity will help buffer some species from the impacts of climate change. [ABSTRACT FROM AUTHOR]

The article reports on the findings of the Columbia Accident Investigation Board (CAIB) regarding the Space Shuttle Columbia accident in the U.S. The CAIB announced that the cause of the loss of Columbia and its crew was a breach in the left wing leading edge reinforced carbon-carbon thermal protection system. The breach was initiated by the impact of thermal insulating foam that had separated from the orbiter's external fuel tank. Also, this breach allowed superheated air to penetrate behind the leading edge and erode the aluminum structure of the left wing, which led to the breakup of the orbiter.

In order to test the sensitivity of regional climate to regional-scale atmosphere-land cover feedbacks, we have employed a regional climate model asynchronously coupled to an equilibrium vegetation model, focusing on the western United States as a case study. CO2-induced atmosphere-land cover feedbacks resulted in statistically significant seasonal temperature changes of up to 3.5°C, with land cover change accounting for up to 60% of the total seasonal response to elevated atmospheric CO2 levels. In many areas, such as the Great Basin, albedo acted as the primary control on changes in surface temperature. Along the central coast of California, soil moisture effects magnified the temperature response in JJA and SON, with negative surface soil moisture anomalies accompanied by negative evaporation anomalies, decreasing latent heat flux and further increasing surface temperature. Additionally, negative temperature anomalies were calculated at high elevation in California and Oregon in DJF, MAM and SON, indicating that future warming of these sensitive areas could be mitigated by changes in vegetation distribution and an associated muting of winter snow-temperature feedbacks. Precipitation anomalies were almost universally not statistically significant, and very little change in mean seasonal atmospheric circulation occurred in response to atmosphere-land cover feedbacks. Further, the mean regional temperature sensitivity to regional-scale land cover feedbacks did not exceed the large-scale sensitivity calculated elsewhere, indicating that spatial heterogeneity does not introduce non-linearities in the response of regional climate to CO2-induced atmosphere-land cover feedbacks. [ABSTRACT FROM AUTHOR]

BSTRACT: Physicochemical properties and acceptance by Asian consumers in the United States of 3 commercially U. S.-grown and 12 imported jasmine rice samples were evaluated. Rice kernels, flour, and starch were characterized for physical, chemical, pasting, and thermal properties. Amylose content, gel type, hardness-to-stickiness ratio, surface fat, protein, and pasting properties significantly affected the eating and cooking qualities and physical appearances of the rice samples; these variables were key to distinguishing the major quality differences and to differentiating U. S.-grown from imported jasmine rice. Data collected from this study could be useful to rice producers, importers, or rice breeders for understanding the physicochemical characteristics of aromatic jasmine rice and its acceptance by Asian consumers. [ABSTRACT FROM AUTHOR]

Examines the material and thermal roles of basalt in calc-alkaline magmatism for the generation of voluminous andesitic to rhyolitic volcanism in eastern Nevada. Crustal contribution to magmatism; Chemical variation in the volcanic suite; Crustal heating, melting and assimilation.

The hypothesis is tested that the greater exterior surface area of textured vessels increases the rate of heating, during food preparation, as compared to vessels with smoothed exterior sur- faces. Experiments are performed on replicated corrugated bowls, a particular type of exterior texturing commonly found in the prehistoric sw United States. The experiments show that corrugated vessels do not heat at a faster rate than comparable plainware pots. The paper concludes with alternative explanations and suggestions for further research. [ABSTRACT FROM AUTHOR]

An essential first step to deep into the knowledge of the mechanisms of action that underlie the use of clay-based spring water gels is their design and development according to standardized protocols and procedures. Hydrogels with two spring waters and two clay excipients, sepiolite (PS9) and palygorskite (G30), were studied. The excipients were fully characterized as regards their identity, purity and richness, as well as their textural features, cation exchange capacities and zeta-potential. Conductivity, pH and ionic composition of spring waters were also assessed. Rheological and thermal properties of hydrogels were monitored through time. PS9 complied with identity, richness and purity descriptions of "Magnesium silicate" (or "Magnesium trisilicate") United States and European Pharmacopoeia monographs', whereas G30 satisfied "Attapulgite" monograph. Cooling rates of 10% w /w spring water hydrogels were adequate for topical application as thermotherapic agents. Gel-like systems obtained with PS9 showed higher viscosities and yield values than G30 hydrogels, the type of spring water not exerting significant influence. The properties remained almost constant during a period of 2 months, ensuring quality standards. Longer periods resulted in unforeseeable changes in properties ascribed to water losses. Unlabelled Image • Spring water/fibrous clays hydrogels were designed and fully characterized. • Sepiolite hydrogels showed higher viscosities and yield values than palygorskite's. • Purity, thermal properties and rheology were found acceptable for balneotherapy. • Properties of studied hydrogels remained stable for 2 months. • Preservation times longer than 2 months are discouraged due to unpredictable changes. [ABSTRACT FROM AUTHOR]

The article reports on the strange observations of the El Reno, Oklahoma, Mesonet (ELRE) site. Inversions of 10 degrees Celsius or greater between 1.5 and 9 meters above the ground are measured at the Menoset site. Inversions at ELRE occur due to rapid cooling near the surface shortly after sunset when conditions are calm, clear, and dry. The air temperature at ELRE can be significantly cooler than other surrounding Mesonet sites. The standard siting requirements established by the World Meteorological Organization.

This article comments on temperature trend results, referred to as MAPP, that estimate surface temperature trends over the U.S. due to aircraft-induced contrails and cirrus, to be in good agreement with corresponding observations over the period 1973 to 1994. MAPP reach this conclusion based on a simple model calibrated using general circulation model results. Depending on the assumed cirrus optical depth, MAPP estimate an annual-mean surface warming trend over the U.S. However, the author believes that MAPP significantly overestimate the climate impact of aircraft-induced clouds.

The article reports that the term" windchill factor" was coined in 1939 by Antarctic explorer Paul A. Siple. During the 1940s, Siple and Charles F. Passel conducted experiments with a waterfilled plastic cylinder to see how long it took water to freeze at various temperatures. The beginning water temperature, the air temperature, and the wind speed all affected the time required to freeze the cylinder. The theory was that exposed flesh would freeze at the same rate when the temperature was subzero— whether that was the calm air temperature or the equivalent windchill temperature. The body will never cool to temperatures that are less than the actual air (no wind) temperature. Likewise, car engines will cool to the air temperature faster on windy days, but they will never cool to less than the air temperature.

Presents the earth temperature posted by several U.S. states from May to June 2003. San Angelo, Texas; Tucson, Arizona; Spokane, Washington State.