Department of Climate and Space Sciences and Engineering in the College of Engineering at the University of Michigan

CLaSP Seminar Series - Dr. Mike Wong

Date: October 11, 2018
Time: 3:30 pm - 5:00 pm
Location: CSRB Auditorium, room 2246

Our guest for this week's CLaSP Seminar Series will be Dr. Mike Wong of UC Berkeley. Please join us! 

Title: "Following the Lightning: Convective Activity in Giant Planet Atmospheres"

Abstract: Just like Earth, moist convection in the observable weather layers of Jupiter and Saturn seems to be driven by water (even though exotic non-water ices also form clouds in giant planet atmospheres). But unlike Earth, moist air in these hydrogen-dominated atmospheres is actually heavier than dry air. As a result, molecular weight stratification acts to suppress convection. Theoretical studies have shown that the molecular weight stratification results in episodic convection, where the duration of quiescent intervals increases with water abundance in the planet's atmosphere. 

Lightning is a common feature in both terrestrial and giant planet moist convection. Lightning flashes on Jupiter and Saturn have been detected both through night-side visible light imaging, as well as through radio waves. On Jupiter, lightning has been associated with storms spanning the full range of observed storm length scales, from 100s to 1000s of kilometers. Saturn seems to lack small-scale lightning storms, with lightning only occurring in 1000-km scale superstorms. The lack of small lightning storms on Saturn may be due to convective inhibition from molecular weight stratification, a line of reasoning that is consistent with a greater water abundance on Saturn than on Jupiter.

Multiple Juno instruments have detected radio emission from lightning strokes on Jupiter. In particular, Juno has seen lightning associated with a massive (5000-km scale) convective superstorm, and with cyclonic vortices. I will present exciting new observations of these atmospheric features from the Earth-based
campaign of supporting observations, which reveal velocity fields, cloud structure, haze distributions, and compositional and thermal anomalies associated with convective storms and cyclones.  The ultimate goal of assembling these observations is to understand the convective process on giant planets. 

Upcoming Events

January 24th
3:30 pm - 5:00 pm
CLaSP Seminar Series - Prof. David Southwood
January 31st
3:30 pm - 5:00 pm
CLaSP Seminar Series - Prof. Anantha Aiyyer
February 7th
3:30 pm - 5:00 pm
CLaSP Seminar Series - Prof. Dustin Schroeder
February 14th
3:30 pm - 5:00 pm
CLaSP Seminar Series - Prof. James Kasting
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