Tropical cyclone simulation and response to CO₂ doubling in the GFDL CM2.5 high-resolution coupled climate model

Globally, TC frequency decreases (−19%) while the intensity increases (+2.7%) in response to CO₂ doubling, consistent with previous studies. The average TC lifetime decreases by −4.6%, while the TC size and rainfall increase by about 3% and 12%, respectively. These changes are generally reproduced across the different basins in terms of the sign of the change, although the percent changes vary from basin to basin and within individual basins.

For the Atlantic basin, although there is an overall reduction in frequency from CO₂ doubling, the warmed climate exhibits increased interannual hurricane frequency variability so that the simulated Atlantic TC activity is enhanced more during unusually warm years in the CO₂-warmed climate relative to that in unusually warm years in the control climate.