title: A heat vulnerability index to improve urban public health management in San Juan, Puerto Rico.
abstract: Increased frequency and length of high heat episodes are leading to more cardiovascular issues and asthmatic responses among the population of San Juan, the capital of the island of Puerto Rico, USA. An urban heat island effect, which leads to foci of higher temperatures in some urban areas, can raise heat-related mortality. The objective of this research is to map the risk of high temperature in particular locations by creating heat maps of the city of San Juan. The heat vulnerability index (HVI) maps were developed using images collected by satellite-based remote sensing combined with census data. Land surface temperature was assessed using images from the Thermal Infrared Sensor flown on Landsat 8. Social determinants (e.g., age, unemployment, education and social isolation, and health insurance coverage) were analyzed by census tract. The data were examined in the context of land cover maps generated using products from the Puerto Rico Terrestrial Gap Analysis Project (USDA Forest Service). All variables were set in order to transform the indicators expressed in different units into indices between 0 and 1, and the HVI was calculated as sum of score. The tract with highest index was considered to be the most vulnerable and the lowest to be the least vulnerable. Five vulnerability classes were mapped (very high, high, moderate, low, and very low). The hottest and the most vulnerable tracts corresponded to highly built areas, including the Luis Munoz International Airport, seaports, parking lots, and high-density residential areas. Several variables contributed to increased vulnerability, including higher rates of the population living alone, disabilities, advanced age, and lack of health insurance coverage. Coolest areas corresponded to vegetated landscapes and urban water bodies. The urban HVI map will be useful to health officers, emergency preparedness personnel, the National Weather Service, and San Juan residents, as it helps to prepare for and to mitigate the potential effects of heat-related illnesses.
authors.affiliation: Environmental Health Department, Graduate School of Public Health, University of Puerto, Rico, Medical Sciences Campus, P.O. Box 365067, San Juan, 00936, Puerto Rico. pablo.mendez1@upr.edu.
authors.forename: Pablo
authors.initials: P
authors.lastname: Méndez-Lázaro
authors.affiliation: Institute for Marine Remote Sensing, College of Marine Science, University of South Florida, 140 7th Ave. South, St. Petersburg, FL, 33701, USA.
authors.forename: Frank E
authors.initials: FE
authors.lastname: Muller-Karger
authors.affiliation: Institute for Marine Remote Sensing, College of Marine Science, University of South Florida, 140 7th Ave. South, St. Petersburg, FL, 33701, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Otis
authors.affiliation: Institute for Marine Remote Sensing, College of Marine Science, University of South Florida, 140 7th Ave. South, St. Petersburg, FL, 33701, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: McCarthy
authors.affiliation: National Weather Service, San Juan, PR Weather Forecast Office, 4000 Carretera 190, Carolina, PR, 00979, Puerto Rico.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Rodríguez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002947:Cities; D006358:Hot Temperature; D006801:Humans; D008875:Middle Aged; D011634:Public Health; D011647:Puerto Rico; D063809:Satellite Imagery; D055815:Young Adult
keywords: Climate change; Heat vulnerability index; Landsat 8-Thermal Infrared Sensor; San Juan, Puerto Rico; Urban heat island