Coronavirus Information for the UC San Diego Community

Our leaders are working closely with federal and state officials to ensure your ongoing safety at the university. Stay up to date with the latest developments. Learn more.

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
Volume62
Pagination43-56
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
Abstract

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.

DOI10.1007/s00484-017-1357-6
Short TitleInt J BiometeorolInt J Biometeorol
Alternate JournalInt J Biometeorol
Student Publication: 
No