The impact of heat waves on daily mortality in Belgrade (Serbia) during summer

Abstract

In this paper, we are dealing with two extreme events in temperature and population – heat wave and mortality. Our aim is to assess the relation between high temperatures and daily mortality counts during the summer months in the period 2000–2010 in Belgrade (Serbia). In order to establish this connection, we used Poisson regression and two different measures of heat wave: Warm Spell Duration Index (WSDI) and apparent temperature (Tapp). As mean daily temperature increases over 90th, 95th and 99th percentiles, average number of deaths increases for 15.3% (p < .01), 22.4% (p < .05) and 32.0% (insignificant for p < .1). We tested three different thresholds (90th, 95th, 99th) for WSDI and Tapp in order to separate the hottest heat-wave episodes. On average, mortality is higher than expected for 13.4%, 16.7% and 28.3% (90th, 95th and 99th percentiles for WSDI) and 16.1%, 17.3% and 32.5% (90th, 95th and 99th percentiles for Tapp). Estimated mortality excess with heat-wave indices is in accordance with regression output, meaning that WSDI and Tapp are good tools for heat-wave identification. During the most severe episode in July 2007, absolute temperature maximum (43.6°C) and daily maximum mortality counts (94 dead) were recorded in the same day (24 July 2007).