Science Seminars

12/9/2015- When it Rains on Titan, it Pours; and then it Evaporates.

Speaker: Scot Rafkin (SwRI)
Date: Wednesday, Dec 09, 2020
Time: 3:00 PM
Location: SPSC W120

Seminar Abstract:

Titan has an active methane cycle that is analogous in many ways to the water cycle on Earth. For these cycles to be stable, the net precipitation to the surface must balance the net evaporation from the surface. This talk focuses on one of Titan’s major precipitation mechanisms and one of Titan’s important evaporation processes. Cloud resolving simulations of Titan’s storms will be presented to describe the dynamics and thermodynamics of the storms under different large-scale conditions. As on Earth, variations in humidity and wind shear will be shown to drive significant variations in storm structure, longevity, precipitation rate and precipitation volume.  Following this, attention will shift to evaporation from methane lakes. Numerical simulations of the atmospheric circulation above Titan lakes will demonstrate the importance of both methane-induced buoyancy and the thermal circulations associated with the contrast between land and lake temperatures. The dependence of sensible and latent heat fluxes on both lake and atmospheric characteristics will be shown to produce a process whereby the net evaporation is reduced over what might be intuitively expected. The talk concludes by describing the possible interconnection between Titan’s storms, aeolian processes, and evaporation.