Observed Relationship between Sea Surface Temperature and the Maximum Intensity of Tropical Cyclones

A consequential issue of global warming is that it increases sea surface temperature (SST),
potentially increasing the energy available to tropical cyclones (TCs). This raises the question of whether
TCs are able to become more intense due to increases in SST. The aim of this study is to document the
relationship between SST and TC intensity in five ocean basins. TC position and intensity data are obtained
for a 33-year period (1982-2014) from the North Atlantic, East Pacific, western North Pacific, North Indian,
and Southern Hemisphere basins. SST and SST anomaly data for each TC position and time (as well as two
days before and two days after TC passage) are obtained from the 0.25¢ª NOAA Optimum Interpolation Sea
Surface Temperature (OISST) dataset. We examine the relationship between SST and intensity at all times
for all TCs, as well as the relationship between SST and TC maximum intensity. We also investigate how
TC passage affects SST by analyzing how SST changes from two days before to two days after TC passage.
We find stronger TCs are associated with higher SST values, though the vast majority of TCs are much
weaker than the maximum intensity observed at each SST. The North Atlantic basin is unique in that a
substantial number of TCs attain their maximum intensity at SST values below 25¢ªC. We also find that the
degree of SST reduction during TC passage shows weakly positive correlations with TC intensity and with
pre-storm SST.