Links between the spatial distribution of the surface urban heat island and heat-related mortality in Prague, Czech Republic

Episodes of extremely high temperatures (heatwaves) are associated with an increased risk of human mortality. People living in cities are at the most significant risk of heat-related mortality due to the urban heat island effect. Although most studies investigate the impact of heat stress on mortality in a city as a whole, the magnitude of the heat stress in a particular part of the city depends on its physical characteristics.

Our study aims to investigate spatio-temporal links between the spatial distribution of the surface urban heat island intensity (SUHII) and heatwave-related mortality in Prague, the Czech Republic. We will analyse daily all-cause mortality in ten Prague districts between 2001 and 2010. A mortality baseline in each district will be determined using generalized additive models adjusted for long-term trends and seasonal and weekly cycles. Relative deviations from the baseline mortality will be calculated to quantify excess mortality during heat waves, defined as periods of at least three consecutive days with a mean daily temperature higher than the 95th percentile of the annual distribution. Six major heatwaves will be selected to investigate the links between the spatial distribution of SUHII and heat wave-related mortality. Daily MODIS land surface temperature images will be used to analyse the spatio-temporal changes in SUHII during the major heatwaves. Spatial statistics tools in ArcGIS will be used to investigate the spatio-temporal patterns.

Our study hypothesizes that the spatial distribution of heat-related mortality is associated with the distribution of SUHII during the major heatwaves. Due to climate change, the frequency and intensity of heatwaves are expected to increase, and the urban heat island intensity is likely to increase in response to heatwaves. The results of our study will help to identify areas in Prague with the most significant impact of urban design on heat-related mortality. This information is vital for identifying hot spots of heat-related mortality and developing strategies to mitigate heat stress in the city.