Reduced Sensitivity of Tropical Cyclone Intensity and Size to Sea Surface Temperature in a Radiative-Convective Equilibrium Environment


9 It has been challenging to project the tropical cyclone intensity, structure and destructive 10 potential changes in a warming climate. Here we compare the sensitivities of tropical cyclone 11 intensity, size and destructive potential to sea-surface warming with and without a pre-storm 12 atmospheric adjustment to an idealised state of Radiative-Convective Equilibrium (RCE). 13 Without RCE, we find large responses of tropical cyclone intensity, size and destructive 14 potential to sea surface temperature changes, which is in line with some previous studies. 15 However, in an environment under RCE, the tropical cyclone size is almost insensitive to sea 16 surface temperature changes, and the sensitivity of intensity is also much reduced to 3-4% o C -17 1 . Without the pre-storm RCE adjustment, the mean destructive potential during the mature 18 stage increases by about 25% o C -1 . However, in an environment under RCE, the sensitivity of 19 destructive potential to sea-surface warming is only about 3-4% o C -1 . Further analyses show 20 that the reduced response of tropical cyclone intensity and size to sea-surface warming under 21 RCE can be explained by the reduced thermodynamic disequilibrium between the air 22 boundary layer and the sea surface due to the RCE adjustment. When conducting large-scale 23

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