The Effects of Climate Change on Tropical Cyclones

The possibility of more intense tropical cyclones in a greenhouse gas-warmed climate has been suggested by both theoretical studies of the Maximum Potential Intensity of tropical cyclones and by simulation studies with hurricane models. 

The goal of this project is to explore the sensitivity of simulated tropical cyclone intensities over a large parameter space, varying both lapse rates and sea surface temperatures and the effects of hurricane/ocean coupling.

Our simulations indicate that increasing either SST or CAPE tend to produce stronger storms while enhanced upper tropospheric warming (relative to the surface warming) tend to produce weaker storms. The lapse rate change in  the troposphere  related to a CO₂-induced global warming can offset hurricane intensity increase due to the  SST increase. This implies that the magnitude of hurricane intensity increase due to climate warming will be much less than it was estimated by only considering the effect of SST increase.  

In the coupled simulations, tropical cyclone-ocean interaction significantly reduces the intensity of simulated storms. However, the net impact of ocean coupling on the simulated CO₂ warming-induced intensification of tropical cyclones is relatively minor. For both coupled and uncoupled simulations, the percentage increase in maximum surface wind speeds varies from about 3 to 10%.