The investigators will conduct a focused on the ionospheric effects of sudden stratospheric warmings. This project will focus on comprehensive experimental studies, using existing experimental data as well as new data from dedicated experimental campaigns. The aim is to (1) improve understanding of the relationship between sudden stratospheric warmings (SSW) and the variations in the ionosphere/thermosphere system and (2) to characterize these variations.
The dynamic coupling of the atmosphere-ionosphere system is a complex interdisciplinary problem. Current thinking suggests that the upward propagation of internal atmospheric waves (planetary waves, tides, gravity waves) from the lower atmosphere is an important source of energy and momentum for the thermosphere and embedded ionosphere. SSW is the clearest and strongest manifestation of the coupling in the atmosphere-ionosphere system. Recent studies suggest that a SSW couples all atmospheric layers from the ground to the thermosphere and from the poles to the equator. However, the mechanism of this coupling is only partly resolved. While the processes in the lower and middle atmosphere are related to planetary wave anomalies, the coupling to the upper layers and the roles of planetary waves, tides and gravity waves, are less clear. This research will be based on a unique combination of new measurements at the NSF Incoherent Scatter Radar facilities and in-depth case studies of multiple ionospheric parameters over a large altitude range. The results will illuminate the kind of variations can occur in the ionosphere and thermosphere during large changes in stratospheric dynamics and temperature. The focus on large dynamical events with strong vertical coupling holds promise for discovering new sources and mechanisms of quiet-time ionospheric and thermospheric variability. Understanding the roles played by planetary waves and tides is a crucial step in understanding and predicting the state of ionosphere and thermosphere. The study will foster collaboration between international researchers, support a young scientist from an underrepresented group, and involve several undergraduate students through MIT's Undergraduate Research Opportunities (UROP) program and the NSF's Research Experience for Undergraduates (REU) program.