Uncertainty in Hurricanes and Global Warming

The marked increase in land-falling hurricanes in Florida and Japan in 2004 has raised questions about whether global warming is playing a role. In his Perspective, Trenberth explains that the observational hurricane record reveals large natural variability from El NiA±o and on multidecadal time scales, and that trends are therefore relatively small. However, sea surface temperatures are rising and atmospheric water vapor is increasing. These factors are potentially enhancing tropical convection, including thunderstorms, and the development of tropical storms. These changes are expected to increase hurricane intensity and rainfall, but the effect on hurricane numbers and tracks remains unclear.