IGPP Seminar Series

The transition to strong convection

by Prof. David Neelin
Dept. of Atmospheric and Oceanic Sciences and IGPP, UCLA

Abstract

Atmospheric convection and the associated rainfall is a key process---and one of the most challenging to correctly represent---in climate and weather models. Here we present some new angles on this old problem, along with indications of how they mesh with existing approaches, notably the convective quasi-equilibrium postulate of Arakawa, and recent stochastic convective parameterizations. In one angle, analysis of new data sets for tropical vertical structure support important aspects of the quasi-equilibrium postulate, while suggesting modifications (Holloway and Neelin, JAS, 2007). In another, the transition to strong tropical deep convection has recently been shown in satellite data sets to exhibit a number of properties of a continuous phase transition and associated critical phenomena (Peters and Neelin, Nature Phys., 2006). Besides the intellectual interest of putting atmospheric moist convective phenomena into correspondence with critical phenomena in other fields, practical implications include empirical constraints on this transition.
Tuesday, 30 January 2007
3853 Slichter Hall
Refreshments at 3:45 PM
Lecture at 4:00 PM