Heliosphere-Atmosphere Coupling via Energetic Particle Precipitation
Abstract
A long-standing goal in the Aeronomy community is to identify and explain the atmospheric processes that indirectly amplify the effects of solar and magnetospheric input. These processes initiate nonlinear feedbacks that couple all regions of the atmosphere, impacting weather and climate throughout. This lecture will focus on how energetic particle precipitation (EPP) influences the middle atmosphere, and how coupling processes amplify these impacts. EPP refers to energetic electrons and protons impinging on the Earth's atmosphere after they have been accelerated by solar and magnetospheric activity. The effects of EPP on the middle atmosphere can be divided into two categories, direct and indirect. The direct effect refers to the local production of reactive odd nitrogen (NOx = N+NO+NO2) and odd hydrogen (HOx = H+OH+HO2) by reactions that are triggered by EPP. The indirect effect refers primarily to the transport of EPP-produced NOx (EPP-NOx), which is relatively long-lived in the mesosphere and lower thermosphere (MLT) during the polar winter. Once EPP-NOx is transported from the MLT into the stratosphere, usually within the polar vortex, it can impact catalytic destruction of ozone, a radiatively important gas. This presentation will provide a historical perspective and will summarize the current state of understanding of EPP impacts on the middle atmosphere, and their broader implications. Outstanding questions and future directions will be discussed.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSA14A..01R
- Keywords:
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- 7599 General or miscellaneous;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY;
- 7899 General or miscellaneous;
- SPACE PLASMA PHYSICS;
- 7999 General or miscellaneous;
- SPACE WEATHER