Authors: Robert Davis*, University of Virginia, David M. Hondula, Arizona State University, Humna Sharif, Yale University
Topics: Climatology and Meteorology, Medical and Health Geography
Keywords: climate, environmental health, diurnal temperature range
Session Type: Paper
Presentation File: No File Uploaded
Numerous studies have demonstrated that days with a large diurnal temperature range (DTR) are associated with increased morbidity and mortality, but the physiological reasons remain unclear. We perform a detailed climatological analysis of these relationships for Charlottesville, Virginia, by comparing an 14-year daily record of emergency department visits to the DTR climatology. DTR is positively correlated with maximum temperature in all months but is effectively uninfluenced by the variation of minimum temperature in the cool season. After modeling ED visit counts using a distributed lag nonlinear model that includes temperature, DTR, and season as predictors, we find ED visit increases to be associated with very cold days in winter, when nighttime temperatures can approach the lowest annual values. Conversely, in the warm season, high DTR mostly occurs on dry, pleasant days when morning dew point temperatures are low. By understanding the climatological nature of DTR variability and thereby focusing research on the specific weather conditions associated with health impacts, it may be possible to understand the reasons for these observed responses.