NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
GEM-CEDAR Challenge: Poynting Flux at DMSP and Modeled Joule HeatPoynting flux into the ionosphere measures the electromagnetic energy coming from the magnetosphere. This energy flux can vary greatly between quiet times and geomagnetic active times. As part of the Geospace Environment Modeling-coupling energetics and dynamics of atmospheric regions modeling challenge, physics-based models of the 3-D ionosphere and ionospheric electrodynamics solvers of magnetosphere models that specify Joule heat and empirical models specifying Poynting flux were run for six geomagnetic storm events of varying intensity. We compared model results with Poynting flux values along the DMSP-15 satellite track computed from ion drift meter and magnetic field observations. Although being a different quantity, Joule heat can in practice be correlated to incoming Poynting flux because the energy is dissipated primarily in high latitudes where Poynting flux is being deposited. Within the physics-based model group, we find mixed results with some models overestimating Joule heat and some models agreeing better with observed Poynting flux rates as integrated over auroral passes. In contrast, empirical models tend to underestimate integrated Poynting flux values. Modeled Joule heat or Poynting flux patterns often resemble the observed Poynting flux patterns on a large scale, but amplitudes can differ by a factor of 2 or larger due to the highly localized nature of observed Poynting flux deposition that is not captured by the models. In addition, the positioning of modeled patterns appear to be randomly shifted against the observed Poynting flux energy input. This study is the first to compare Poynting flux and Joule heat in a large variety of models of the ionosphere.
Document ID
20170002665
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Rastaetter, Lutz (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Shim, Ja Soon (Catholic Univ. of America Washington, DC, United States)
Kuznetsova, Maria M. (NASA Goddard Space Flight Center Greenbelt, MD United States)
Kilcommons, Liam M. (Colorado Univ. Boulder, CO, United States)
Knipp, Delores J. (Catholic Univ. of America Washington, DC, United States)
Codrescu, Mihail (National Oceanic and Atmospheric Administration Boulder, CO, United States)
Fuller-Rowell, Tim (National Oceanic and Atmospheric Administration Boulder, CO, United States)
Emery, Barbara (National Center for Atmospheric Research Boulder, CO, United States)
Weimer, Daniel R. (Virginia Polytechnic Inst. and State Univ. Blacksburg, VA, United States)
Cosgrove, Russell (SRI International Corp. Menlo Park, CA, United States)
Wiltberger, Michael (National Center for Atmospheric Research Boulder, CO, United States)
Raeder, Joachim (New Hampshire Univ. Durham, NH, United States)
Li, Wenhui (New Hampshire Univ. Durham, NH, United States)
Toth, Gabor (Michigan Univ. Ann Arbor, MI, United States)
Welling, Daniel (Michigan Univ. Ann Arbor, MI, United States)
Date Acquired
March 29, 2017
Publication Date
February 18, 2016
Publication Information
Publication: Space Weather
Volume: 14
Issue: 2
ISSN: 1542-7390
Subject Category
Geophysics
Report/Patent Number
GSFC-E-DAA-TN40761
Funding Number(s)
CONTRACT_GRANT: NNX13AG07G
CONTRACT_GRANT: NSF AGS 1144154
Distribution Limits
Public
Copyright
Other