Dynamical Systems Seminar: Yue-Kin Tsang
Advection-condensation of water vapor in a model of coherent stirring Ìý
Joint talk with Atmospheric and Oceanic Sciences (ATOC)
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Date and time:Ìý
Thursday, October 23, 2014 - 2:00pm
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ECCR 257
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Atmospheric water vapor is an essential ingredient of weather and being a potent greenhouse gas, its distribution has a strong impact on climate. The dynamics of atmospheric moisture has previously been studied (Pierrehumbert et al., O’Gorman & Schneider, Sukhatme & Young) using idealized one-dimensional stochastic models in which moisted air parcels are advected by spatially decorrelated random motion and condensation occurs when the specific humidity of a parcel exceeds the local value of a spatially dependent saturation profile. However, coherent sturctures are abundant in the atmosphere. In this work we examine the effect of a coherent flow represented by a single vortex which adds a deterministic component to the random motion of the air parcels. We consider both the initial-value and the steady-state problem of our two-dimensional model and derive the probability distribution of the moisture field. Theoretical predictions are verified by Monte Carlo simulations.