Principal Investigator Paul O'Gorman
The amount of water vapor in the atmosphere responds sensitively to changes in temperature. The amount of water vapor increases by over 20% for a 3K rise in temperature if the relative humidity remains approximately constant. Climate model simulations do predict changes in the distribution of relative humidity, but the overall change is relatively small. This has implications for many aspects of atmospheric dynamics when considering global warming or very warm past climates. An outstanding challenge involves fully incorporating the effect of water vapor and latent heat release into theories of how, for example, the extent of the Hadley cell, the extratropical storm track position, or the strength of extratropical storms change as climate changes.