Increasing Atlantic hurricane activity in prospect from global warming

The 2004 and 2005 hurricane seasons with seven intense hurricane landfalls on the U.S. and an estimated total damage bill approaching US$ 200bn have proved exceptionally active and damaging. This elevated activity is raising concerns about the possible influence of global warming and whether further increases in hurricane activity and greater hurricane losses may be expected in the coming decades. This presentation will review the observational evidence for global warming being a contributory factor to the recent high activity. It will then present the results of new research giving projections for how the North Atlantic ACE (Accumulated Cyclone Energy) index and numbers of North Atlantic intense hurricanes and hurricanes will change due to global warming through to 2100. All projections include 95% confidence intervals and are presented for two different CO₂ loading scenarios. The analysis includes data from the leading coupled general circulation models being used for IPCC4 that have sound and stable tropical teleconnections. Our findings indicate that the current and future impact of global warming on Atlantic hurricane activity may be higher than thought previously.