Temperature-Mortality Projections in Kuwait: The Immediate Future 2021-2060

Abstract

Background-A number of climate forecasting studies have shown that the Arabian Peninsula could be uninhabitable by the end of the century due to extreme hot temperatures that will exceed the threshold of human adaptability. However, these studies did not use country-specific mortality rates and assumed a business-as-usual climate change scenario (RCP8.5). We have done previous analyses in Kuwait using historical mortality data and found an alarming increase in the risk of all cause and cardiovascular mortality among vulnerable subpopulations within the range of current temperatures. Objective-We aimed to extend the temperature-mortality relationship into the immediate future climate from 2021 to 2060 in Kuwait under an intermediate emission scenario (RCP4.5), which is a reasonable scenario that considers some climate mitigation policies. Methods-We used an ensemble of 15 RCP4.5 models that forecasted future daily meteorological data from the CMIP5 initiative of the IPCC. We applied bias correction to the monthly temperature means using historical weather data from 2006 to 2016 obtained from Kuwait Airport. We constructed a time-series of historical and future daily average temperatures, and projected attributable excess mortality for cold and hot temperatures derived from distributed lag non-linear models compared to non-optimal temperatures. For this analysis, we made two key assumptions: no population change and no adaptation. Results-The average increase in mean temperature by 2060 is 1.84°C. Comparing the 2051-2060 period to the 2006-2016 historical period, the heat-attributable mortality will substantially increase in the future by 2.95% (95% empirical confidence interval [eCI]=0.15 to 9.41), whereas, the mortality due to cold weather will also increase, but with more uncertainty around the estimated percentage of relative excess mortality (3.31%, 95% eCI=-3.13 to 15.97). Conclusions-In inherently hot regions, we still see an increase in mortality burdens due to hot temperatures even for less extreme future climate scenarios.