i) Risks of heat-related mortality would become severe at global and regional scales with high levels of warming and vulnerability . Under these conditions , accounting for adaptation, heat mortality would increase the global CMR by up to 7/10,000 yr-1 by 2100 . For example, the USA would experience a CMR increase of 2-4/10,000 yr-1 by the end of the century  . Also assuming no adaptation and recent vulnerability, most populations of the world would experience an increase of 2-10 percentage points in the percentage of deaths attributable to heat by the end of the century  . Harmful conditions for health are expected to increase in frequency and intensity over all land areas along with the rising temperatures in the coming decades . Projections of exposure are an incomplete measure of risk but suggest the potential for severe impacts. For example, the percent of global population exposed to deadly heat stress would increase from today's 30% to 48-74% by the end of the century depending on level of warming and population distribution . Projected impacts are larger if exposure and/or vulnerability increases due to ageing of the population or increased inequality  and with limited adaptation capacity   . Higher risks are also expected in urban areas owing to hazard amplification  and in highly dense settlements with other environmental hazards such as air pollution .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report