Short Warm Distribution Tails Accelerate the Increase of Humid‐Heat Extremes Under Global Warming
Yianna Bekris, Paul C. Loikith, J. David Neelin
Abstract
Abstract Humid‐heat extremes threaten human health and are increasing in frequency with global warming, so elucidating factors affecting their rate of change is critical. We investigate the role of wet‐bulb temperature ( T W ) frequency distribution tail shape on the rate of increase in extreme T W threshold exceedances under 2°C global warming. Results indicate that non‐Gaussian T W distribution tails are common worldwide across extensive, spatially coherent regions. More rapid increases in the number of days exceeding the historical 95th percentile are projected in locations with shorter‐than‐Gaussian warm side tails. Asymmetry in the specific humidity distribution, one component of T W , is more closely correlated with T W tail shape than temperature, suggesting that humidity climatology strongly influences the rate of future changes in T W extremes. Short non‐Gaussian T W warm tails have notable implications for dangerous humid‐heat in regions where current‐climate T W extremes approach human safety limits.