Global Scaling of Rainfall With Dewpoint Temperature Reveals Considerable Ocean?Land Difference

Short-duration rainfall extremes are expected to intensify with warming at around 7%/K, following the Clausius-Clapeyron (CC) relation, causing concomitant increases in flash floods. Observed hourly show consistent CC-scaling dewpoint temperature across all land regions. Here, we use two global climate reanalysis products (ERA5 and MERRA-2) examine consistency scaling observations, ungauged regions over oceans. We find that reanalyzes underestimate observed scaling, but ERA5 provides better estimates than MERRA-2. Scaling rates high latitudes midlatitudes similar CC, while tropics mixed negative- super-CC seen. underestimation of is related deficiencies simulations extreme orographically complex convection dominated Importantly, both indicate ocean substantially higher land, implications for weather events originating ocean.