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The influence of surface type on the absorbed radiation by a human under hot, dry conditions

TitleThe influence of surface type on the absorbed radiation by a human under hot, dry conditions
Publication TypeJournal Article
Year of Publication2018
AuthorsHardin A.W, Vanos J.K
JournalInternational Journal of BiometeorologyInternational Journal of Biometeorology
Date Published2018/01
ISBN Number0020-7128
Accession NumberWOS:000419352000006
Keywordsabsorbed radiation; albedo; arizona; cities; climate; environments; Extreme heat; mean radiant temperature; Phoenix; public square; stress; Thermal comfort; urban climate; urban heat island; urban heat-island

Given the predominant use of heat-retaining materials in urban areas, numerous studies have addressed the urban heat island mitigation potential of various "cool" options, such as vegetation and high-albedo surfaces. The influence of altered radiational properties of such surfaces affects not only the air temperature within a microclimate, but more importantly the interactions of long- and short-wave radiation fluxes with the human body. Minimal studies have assessed how cool surfaces affect thermal comfort via changes in absorbed radiation by a human (R (abs)) using real-world, rather than modeled, urban field data. The purpose of the current study is to assess the changes in the absorbed radiation by a human-a critical component of human energy budget models-based on surface type on hot summer days (air temperatures > 38.5(ay)C). Field tests were conducted using a high-end microclimate station under predominantly clear sky conditions over ten surfaces with higher sky view factors in Lubbock, Texas. Three methods were used to measure and estimate R (abs): a cylindrical radiation thermometer (CRT), a net radiometer, and a theoretical estimation model. Results over dry surfaces suggest that the use of high-albedo surfaces to reduce overall urban heat gain may not improve acute human thermal comfort in clear conditions due to increased reflected radiation. Further, the use of low-cost instrumentation, such as the CRT, shows potential in quantifying radiative heat loads within urban areas at temporal scales of 5-10 min or greater, yet further research is needed. Fine-scale radiative information in urban areas can aid in the decision-making process for urban heat mitigation using non-vegetated urban surfaces, with surface type choice is dependent on the need for short-term thermal comfort, or reducing cumulative heat gain to the urban fabric.

Short TitleInt J BiometeorolInt J Biometeorol
Alternate JournalInt J Biometeorol
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