HR: 11:05h
AN: SA12A-04    [Abstracts]
TI: TIMED/SABER Observations of the Storm-Time E-Region: Morphology, Chemistry, and Energetics
AU: * Mertens, C J
EM: Christopher.J.Mertens@nasa.gov
AF: NASA Langley Research Center, 21 Langley Blvd., Mail Stop 401B, Hampton, VA 23681- 2199, United States
AU: Xu, X
EM: xiaojing_xu@ssaihq.com
AF: SSAI, Inc., 1 Enterprise Pkwy, Hampton, VA 23666, United States
AU: Winick, J R
EM: jeremy.winick@hanscom.af.mil
AF: Air Force Research Laboratories, 29 Randolph Rd., Hanscom, MA 01731-3019, United States
AU: Evans, D S
EM: david.s.evans@noaa.gov
AF: NOAA Space Environment Center, 325 Broadway, Boulder, CO 80303, United States
AU: Fernandez, J R
EM: jfernand.naic.edu
AF: NASA Langley Research Center, 21 Langley Blvd., Mail Stop 401B, Hampton, VA 23681- 2199, United States
AU: Russell, J M
EM: james.russell@hamptonu.edu
AF: Center for Atmospheric Sciences, Hampton University, 23 Tyler St., Hampton, VA 23688, United States
AU: Mlynczak, M G
EM: Martin.G.Mlynczak@nasa.gov
AF: NASA Langley Research Center, 21 Langley Blvd., Mail Stop 401B, Hampton, VA 23681- 2199, United States
AB: A new data product derived from TIMED/SABER measurements of 4.3 um limb emission is the NO+(v) volume emission rate (VER). We have found NO+(v) VER to be versatile analysis tool for studying the E-region response to solar-geomagnetic storms. Enhancements in nighttime 4.3 um emission during storm periods are due to vibrational excitation of NO+ (i.e., NO+(v)), caused by auroral dosing and subsequent ion-neutral chemical reactions, followed by radiative emission at 4.3 um. The NO+(v) VER is derived by (1) removing the background CO2 infrared emission using SABER observations and non-LTE radiation transfer models, and (2) by performing a standard Abel inversion on the residual radiance. Since NO+ is the terminal E-region ion, the NO+(v) VER is an excellent proxy for characterizing the morphology of the E-region response to magnetic disturbances. Analysis of the April 2002 and Halloween 2003 storm periods reveal spatial structure in the NO+(v) VER that is difficult to understand: large enhancements at mid-latitudes, well outside the region of strong auroral precipitation, and a bi- modal distribution in the vertical peak. The maximum NO+(v) VER for each profile occurs at roughly 110 km or 130 km. The International Reference Ionosphere (IRI) model indicates that the E-region electron density peak always occurs at roughly 110 km. In this paper we seek to understand the horizontal and vertical structure of the SABER- derived NO+(v) VER during the April 2002 and Halloween 2003 storm periods by utilizing both measurements and detailed modeling of the E-region chemistry, energetics, and radiation transfer. The morphology of the SABER-derived NO+(v) will be compared with radio occultation profiles of E-region electron densities measured by CHAMP, and with incoherent scatter radar measurement data available through the CEDAR database. In addition, we will model the NO+(v) VER by dynamically driving the field-line interhemispheric plasma (FLIP) model with particle precipitation energy characteristics observed by the NOAA/POES satellites. The FLIP model provides the ion and neutral density inputs for our NO+(v) kinetics model, which provides the NO+(v) densities for the 4.3 um non-LTE radiation transfer calculations used simulate the NO+(v) VER. The modeled NO+(v) VER provides a diagnostic approach to understanding the mechanisms responsible for the spatial structure observed in the SABER-derived NO+(v) VER.
DE: 0355 Thermosphere: composition and chemistry
DE: 0358 Thermosphere: energy deposition (3369)
DE: 2419 Ion chemistry and composition (0335)
DE: 2427 Ionosphere/atmosphere interactions (0335)
DE: 2441 Ionospheric storms (7949)
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting