[IGPP Everyone] Space Physics Seminar - Spring Quarter - Fri.May 21, 2021 - 3:30pm - Zoom

[Marjorie Sowmendran]

SPACE PHYSICS SEMINAR 


DEPARTMENT OF EARTH, PLANETARY, AND SPACE SCIENCES 
DEPARTMENT OF ATMOSPHERIC AND OCEANIC SCIENCES 
UNIVERSITY OF CALIFORNIA, LOS ANGELES 

Join Zoom Meeting 

https://ucla.zoom.us/j/96663537686?pwd=bXVLSVFrU2g5T0dsU2lMQTFtOW5yUT09 


Meeting ID: 966 6353 7686; Passcode: 981246 







" Multi-scale Processes in Ionospheric Physics " 
Roger Varney 
SRI International 



Abstract 




The Earth’s ionosphere is the ionized portion of the upper atmosphere, and prediction of the low Earth orbit (LEO) satellite environment requires detailed understanding of the ionospheric plasma dynamics. The ionosphere mediates energy transfer between the space plasma in the magnetosphere and the neutral gas in the thermosphere, and quantification of the neutral gas heating is needed to forecast thermospheric expansion and its impact on LEO satellite drag. The ionosphere also strongly interacts with radio waves by refracting, diffracting, and scattering space-to-ground communication and navigation signals. Couplings between physical processes occurring at disparate scales in space, time, and particle energy significantly complicate ionospheric dynamics and make the plasma impossible to describe with one physical model operating on a narrow range of scales. Many other areas of Earth and space science face similar challenges describing multi-scale coupling processes. This seminar will review some of the most challenging outstanding multi-scale coupling problems in ionospheric physics, including particle precipitation and conductivity, nonlinear conductivity driven by instabilities, roles of Alfven waves, and acceleration of ions to escape energies by wave-particle interactions. The seminar will then discuss strategies for making progress on these various areas of research by employing new generations of models that resolve meso-scale features, using multi-point satellite observations in clever ways, and expanding the capabilities of ground-based radar techniques. 


Friday, May 21, 2021 

3:30 - 5:00 PM 

In-Charge: C. T. Russell 








-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.igpp.ucla.edu/pipermail/everyone/attachments/20210517/98789ebc/attachment.html>