Northern Eurasia thermal comfort conditions: dynamic by the end of the century

Biometeorological indices are one of the efficient tools for evaluation of the impact climate change might have on human health. In Northern Eurasia, datasets based on ERA5, and ERA-Interim reanalysis demonstrate the opposing trends for repeatability of days with heat and cold stress,For future climate evaluation, 3-hour data of several CMIP6 models was obtained for 1980-2009 and 2080-2100 (ssp 2.4.5, ssp 5.8.5 scenarios). Then the data was interpolated on 1⁰ latitude x 1⁰ longitude grid. Five indices were used for the evaluation of repeatability of thermal comfort conditions: Heat Index (HI), Humindex (HUM), Physiological Equivalent Temperature (PET) for warm season; Wind-Chill Temperature (WCT), Universal Thermal Comfort Index (UTCI) for cold.The results indicate the increase of repeatability of heat stress days by 2100, as well as projected expansion of territory with repeatability > 80 % in summer. Changes of average repeatability between 1980-2009 and 2080-2100 generally exceed zero. Repeatability of days with cold stress decreases significantly. By 2100, repeatability of stress-free days decreases in southern regions and increases in northern. For 1980-2009, linear trend coefficients indicate the existence of two regions (of increase and decrease of repeatability), and this spatial pattern is present by 2080-2100.Results demonstrate the climate becoming less comfortable in southern parts of the Northern Eurasia, and more comfortable in northern parts of the region. Changes in repeatability of heat and cold stress days show increase in the entirety of the region, but repeatability of stress-free days demonstrates complex patterns between different parts of Northern Eurasia.Acknowledgements: This work has been supported by the grant of the Russian Science Foundation, RSF project №23-77-30008 “Seamless integrated modeling of interrelated changes in weather, climate and air quality for the sustainable development of cities and regions of the Arctic and northern Russia in the context of global change climate”.