The super-Clausius-Clapeyron increase of precipitation as a result of convective self-organization
Equilibrium thermodynamics implies an approximate 7%/K increase in saturation vapor pressure at typical near-surface temperatures during mid-latitude summer or in the tropics. Yet, extreme short-term precipitation over land has been observed to increase more strongly than this rate, when comparing to the local near-surface temperature. In search for dynamical, non-equilibrium effects, an invigoration of atmospheric dynamics has been suggested. We here discuss, in how far atmospheric moisture fluxes can be influenced by an increased heating at the surface, how this may lead to intensified extremes and in which ways the convective cloud system might be understood in a simplified, conceptual modeling framework.
Lenderink, Geert, and Erik Van Meijgaard. "Increase in hourly precipitation extremes beyond expectations from temperature changes." Nature Geoscience 1.8 (2008): 511-514. Moseley, Christopher, et al. "Intensification of convective extremes driven by cloud-cloud interaction." Nature Geoscience 9.10 (2016): 748-752. Haerter, Jan O., et al. "Precipitation onset as the temporal reference in convective self-organization", Geophys. Res. Letts (2017), DOI: 10.1002/2017GL073342
Date 8 June, 2017
Place Nordlys, DMI