Applied Heat Transfer in the Development of the New Wind Chill Temperature Chart

Author(s):  
Maurice Bluestein

In November, 2001, the national weather services of the United States and Canada, recognizing inaccuracies in the original, adopted a revised Wind Chill Temperature (WCT) chart. This revision was developed by the authors under a mandate from a joint action group for temperature indicies (JAG/TI) formed by the U.S. Office of the Federal Coordinator for Meteorology. This new chart provides, for a given air temperature and recorded wind speed, that air temperature, the WCT, which would result in the same rate of heat loss from exposed human skin in still air. Values of the WCT are given for a range of air temperatures from −45°F to 40°F and a range of wind speeds from 5 mph to 60 mph. For Canada, the ranges are from −50°C to 10°C and 10 km/hr to 80 km/hr. The new chart was developed using principles of heat transfer, including conduction, forced convection and radiation. Skin tissue resistance was obtained from human studies. This paper describes the application of these principles and will show how these same principles have been used to demonstrate the errors in the original chart developed over 60 years ago by our military in Antarctica and adopted by the U.S. Weather Service in 1973. As was the case for the original chart, a clear night sky has been assumed, thus ignoring any direct solar radiation that would otherwise tend to elevate the WCT. The new chart is unlikely to be the final version long term and this paper will also discuss possible future modifications.

2018 ◽  
Vol 14 (1) ◽  
pp. 44-57
Author(s):  
S. N. Shumov

The spatial analysis of distribution and quantity of Hyphantria cunea Drury, 1973 across Ukraine since 1952 till 2016 regarding the values of annual absolute temperatures of ground air is performed using the Gis-technologies. The long-term pest dissemination data (Annual reports…, 1951–1985; Surveys of the distribution of quarantine pests ..., 1986–2017) and meteorological information (Meteorological Yearbooks of air temperature the surface layer of the atmosphere in Ukraine for the period 1951-2016; Branch State of the Hydrometeorological Service at the Central Geophysical Observatory of the Ministry for Emergencies) were used in the present research. The values of boundary negative temperatures of winter diapause of Hyphantria cunea, that unable the development of species’ subsequent generation, are received. Data analyses suggests almost complete elimination of winter diapausing individuals of White American Butterfly (especially pupae) under the air temperature of −32°С. Because of arising questions on the time of action of absolute minimal air temperatures, it is necessary to ascertain the boundary negative temperatures of winter diapause for White American Butterfly. It is also necessary to perform the more detailed research of a corresponding biological material with application to the freezing technics, giving temperature up to −50°С, with the subsequent analysis of the received results by the punched-analysis.


1997 ◽  
Vol 24 (1) ◽  
pp. 117-141 ◽  
Author(s):  
T. A. LEE

This study represents part of a long-term research program to investigate the influence of U.K. accountants on the development of professional accountancy in other parts of the world. It examines the impact of a small group of Scottish chartered accountants who emigrated to the U.S. in the late 1800s and early 1900s. Set against a general theory of emigration, the study's main results reveal the significant involvement of this group in the founding and development of U.S. accountancy. The influence is predominantly with respect to public accountancy and its main institutional organizations. Several of the individuals achieved considerable eminence in U.S. public accountancy.


1975 ◽  
Vol 39 (1) ◽  
pp. 93-102 ◽  
Author(s):  
R. M. Smith ◽  
J. M. Hanna

Fourteen male subjects with unweighted mean skinfolds (MSF) of 10.23 mm underwent several 3-h exposures to cold water and air of similar velocities in order to compare by indirect calorimetry the rate of heat loss in water and air. Measurements of heat loss (excluding the head) at each air temperature (Ta = 25, 20, 10 degrees C) and water temperature (Tw = 29–33 degrees C) were used in a linear approximation of overall heat transfer from body core (Tre) to air or water. We found the lower critical air and water temperatures to fall as a negative linear function of MSF. The slope of these lines was not significantly different in air and water with a mean of minus 0.237 degrees C/mm MSF. Overall heat conductance was 3.34 times greater in water. However, this value was not fixed but varied as an inverse curvilinear function of MSF. Thus, equivalent water-air temperatures also varied as a function of MSF. Between limits of 100–250% of resting heat loss the followingrelationships between MSF and equivalent water-air temperatures were found (see article).


2017 ◽  
Vol 77 (1) ◽  
pp. 171-207 ◽  
Author(s):  
Howard Bodenhorn ◽  
Timothy W. Guinnane ◽  
Thomas A. Mroz

Understanding long-term changes in human well-being is central to understanding the consequences of economic development. An extensive anthropometric literature purports to show that heights in the United States declined between the 1830s and the 1890s, which is when the U.S. economy modernized. Most anthropometric research contends that declining heights reflect the negative health consequences of industrialization and urbanization. This interpretation, however, relies on sources subject to selection bias. Our meta-analysis shows that the declining height during industrialization emerges primarily in selected samples. We also develop a parsimonious diagnostic test that reveals, but does not correct for, selection bias in height samples. When applied to four representative height samples, the diagnostic provides compelling evidence of selection.


2019 ◽  
pp. 135-146
Author(s):  
Lauren Heidbrink

This chapter chronicles how young people experience deportation from the United States to Guatemala. It examines the policies and institutional practices that govern the removal of unaccompanied children and trace the ways in which young people and their families understand and navigate these policies and practices. Through multi-sited ethnographic research in the United States and Guatemala, the chapter reveals the various impacts of the forced “repatriation” of children, exacerbating the very conditions that spurred their migration and causing new interrelated uncertainties and related risks as “deportees.” As they are physically expelled from the United States, deported young people move out of U.S. legal systems. The effects of a forced “return” to their nations of origin produce new challenges such as feelings of isolation and vulnerability as well as danger, such that, in many ways, they continue to be in and moving through regimes of illegality. Demonstrating the long-term and geographically distant effects of the U.S. government’s deportation of children and youth, the chapter outlines the confining character of being out of a system, especially if once in it.


Author(s):  
Kimberly Gray ◽  
John Vienna ◽  
Patricia Paviet

In order to maintain the U.S. domestic nuclear capability, its scientific technical leadership, and to keep our options open for closing the nuclear fuel cycle, the Department of Energy, Office of Nuclear Energy (DOE-NE) invests in various R&D programs to identify and resolve technical challenges related to the sustainability of the nuclear fuel cycle. Sustainable fuel cycles are those that improve uranium resource utilization, maximize energy generation, minimize waste generation, improve safety and limit proliferation risk. DOE-NE chartered a Study on the evaluation and screening of nuclear fuel cycle options, to provide information about the potential benefits and challenges of nuclear fuel cycle options and to identify a relatively small number of promising fuel cycle options with the potential for achieving substantial improvements compared to the current nuclear fuel cycle in the United States. The identification of these promising fuel cycles helps in focusing and strengthening the U.S. R&D investment needed to support the set of promising fuel cycle system options and nuclear material management approaches. DOE-NE is developing and evaluating advanced technologies for the immobilization of waste issued from aqueous and electrochemical recycling activities including off-gas treatment and advanced fuel fabrication. The long-term scope of waste form development and performance activities includes not only the development, demonstration, and technical maturation of advanced waste management concepts but also the development and parameterization of defensible models to predict the long-term performance of waste forms in geologic disposal. Along with the finding of the Evaluation and Screening Study will be presented the major research efforts that are underway for the development and demonstration of waste forms and processes including glass ceramic for high-level waste raffinate, alloy waste forms and glass ceramics composites for HLW from the electrochemical processing of fast reactor fuels, and high durability waste forms for radioiodine.


Plant Disease ◽  
2004 ◽  
Vol 88 (5) ◽  
pp. 523-529 ◽  
Author(s):  
S. Pivonia ◽  
X. B. Yang

Soybean rust (Phakopsora pachyrhizi Sydow) has been known to occur in eastern Asia and Aus-tralia for decades. In recent years, the disease entered Africa and South America and has spread rapidly in these continents. It has become a concern to the U.S. soybean industry. To assess the threat of soybean rust, we used a modeling approach to determine the potential geographical zones where the fungus might overwinter and serve as source areas for seasonal epidemics. Long-term meteorological averages were used to assess the temperature stresses by using CLIMEX, and the dry stress with an algorithm developed in this study. Integration of stresses was used to predict the likelihood of survival of the rust in a defined location. Our results suggest that the new soybean rust invasions in Africa and South America occurred in the areas where the fungus might persist year-round. The main regions where rust has not been reported but might overwinter are located in the western hemisphere, including northern South America, Central America, the Caribbean, Mexico, southern Texas, and Florida. Southeastern China and neighboring areas are suggested as the primary regions where initial spores for soybean rust epidemics in central China are produced. If the disease is to establish in the United States, it is likely to be restricted to parts of Florida and southern Texas during the winter in the frost-free areas or areas where the fungus could overcome short periods of below-freezing temperatures. Occurrence of rust epidemics within the U.S. soybean belt would depend on south-to-north dispersal of uredospores.


2016 ◽  
Vol 41 (1) ◽  
pp. 7-48 ◽  
Author(s):  
Stephen Biddle ◽  
Ivan Oelrich

Many analysts worry that improvements in Chinese missile, sensor, guidance, and other technologies will enable China to deny the U.S. military access to parts of the Western Pacific that the United States has long controlled. Although these “antiaccess, area denial” (A2/AD) capabilities are real, they are a geographically limited long-term threat. As both the United States and China deploy A2/AD capabilities, a new era will emerge in which the U.S. military no longer enjoys today's command of the global commons, but is still able to deny China military hegemony in the Western Pacific. In this new era, the United States will possess a sphere of influence around allied landmasses; China will maintain a sphere of influence over its own mainland; and a contested battlespace will cover much of the South and East China Seas wherein neither power enjoys wartime freedom of surface or air movement. This in turn suggests that the Chinese A2/AD threat to U.S. allies is real but more limited than often supposed. With astute U.S. choices, most U.S. allies in this new system will be imperfectly, but substantially, secure.


1983 ◽  
Vol 26 (1) ◽  
pp. 54-68 ◽  
Author(s):  
Richard J. Schonberger ◽  
James P. Gilbert

Traditional U.S. purchasing is under assault. Japanese purchasing practices, featuring frequent “just-in-time” deliveries in small quantities, have made inroads among Japanese subsidiaries in the United States and more recently in the U.S. auto industry. Just-in-time (JIT) buying tends to be accompanied by a host of structural changes: Long-term, stable buyer-supplier relationships; avoidance of annual rebidding; sole-source contracts; improved containerization; and localized buying, to name just a few. The benefits of JIT purchasing, to both buyer and supplier, include lower material costs, higher productivity, and improved qualify. The strategic advantages—growth of market share and stable relationships—can be significant. Geographical vastness is one of several obstacles in the way of widespread use of JIT buying practices in the United States. The companies that have pioneered in the development of JIT purchasing in this country have demonstrated that most of the obstacles are not insurmountable.


1998 ◽  
Vol 120 (2) ◽  
pp. 255-258 ◽  
Author(s):  
M. Bluestein

The wind chill factor has become a standard meteorologic term in cold climates. Meteorologic charts provide wind chill temperatures meant to represent the hypothetical air temperature that would, under conditions of no wind, effect the same heat loss from unclothed human skin as does the actual combination of air temperature and wind velocity. As this wind chill factor has social and economic significance, an investigation was conducted on the development of this factor and its applicability based on modern heat transfer principles. The currently used wind chill factor was found to be based on a primitive study conducted by the U.S. Antarctic Service over 50 years ago. The resultant equation for the wind chill temperature assumes an unrealistic constant skin temperature and utilizes heat transfer coefficients that differ markedly from those obtained from equations of modern convective heat transfer methods. The combined effect of these two factors is to overestimate the effect of a given wind velocity and to predict a wind chill temperature that is too low.


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