Science Seminars

A New MEPED-Based Precipitating Electron Data Set

Speaker: Josh Pettit (LASP)
Date: Thursday, Jul 23, 2020
Time: 4:00 PM
Location: Zoom

Seminar Abstract:

The importance of energetic particle precipitation for middle atmosphere chemistry has become more widely appreciated in recent years. While solar protons and auroral electrons have been included in global climate modeling studies in the past, advances in recent years have allowed researchers to improve the accuracy of climate simulations of the middle atmosphere by including energetic electrons precipitating from the radiation belts. The work presented here introduces a new energetic electron data set that can be used in future climate model simulations. Measurements made by Medium Energy Proton and Electron Detector (MEPED) instruments onboard both the Polar Orbiting Environmental Satellites and the European Space Agency Meteorological Operational satellites are used to create global maps of precipitating electron fluxes. The electron fluxes are computed using both the 0° and 90° detectors from the MEPED instruments instead of using only the 0° degree detector. Conversion of observed electron count rates in broad energy bins to spectral fluxes uses a linear combination of analytical functions instead of a single function. Two dimensional maps of electron spectral flux are created using Delaunay triangulation to account for the relatively sparse nature of the MEPED sampling. This improves on previous studies that use a 1D interpolation over magnetic local time or l-shell zonal averaging of the MEPED data. Results from Whole Atmosphere Community Climate Model simulations using the new precipitating electron data set are shown to match observations better than simulations using other MEPED-based electron data sets.