Transient response of severe thunderstorm forcing to elevated greenhouse gas concentrations

We investigate the transient response of severe-thunderstorm forcing to the time-varying greenhouse gas concentrations associated with the A1B emissions scenario. Using a five-member ensemble of global climate model experiments, we find a positive trend in such forcing within the United States, over the period 1950-2099. The rate of increase varies by geographic region, depending on (i) low-level water vapor availability and transport, and (ii) the frequency of synoptic-scale cyclones during the warm season. Our results indicate that deceleration of the greenhouse gas emissions trajectory would likely result in slower increases in severe thunderstorm forcing. Citation: Trapp, R. J., N. S. Diffenbaugh, and A. Gluhovsky (2009), Transient response of severe thunderstorm forcing to elevated greenhouse gas concentrations, Geophys. Res. Lett., 36, L01703, doi: 10.1029/2008GL036203.