HR: 14:00h
AN: SA43A-02    [Abstracts]
TI: PFISR and Lidar Observations of the Summer Mesopause Region in August 2007
AU: * Kelley, M C
EM: mikek@ece.cornell.edu
AF: Cornell University, School of Electrical and Computer Engineering, 320 Rhodes Hall, Ithaca, NY 14853, United States
AU: Collins, R L
EM: richard.collins@gi.alaska.edu
AF: University of Alaska Fairbanks, Geophysical Institute and Dept. of Atmospheric Sciences, 903 Koyukuk Drive, Fairbanks, AK 99775, United States
AU: Nicolls, M J
EM: michael.nicolls@sri.com
AF: SRI International, Center for Geospace Studies, 333 Ravenswood Avenue, Menlo Park, CA 94025, United States
AU: Heinselman, C J
EM: craig.heinselman@sri.com
AF: SRI International, Center for Geospace Studies, 333 Ravenswood Avenue, Menlo Park, CA 94025, United States
AU: Varney, R H
EM: rhv5@cornell.edu
AF: Cornell University, School of Electrical and Computer Engineering, 320 Rhodes Hall, Ithaca, NY 14853, United States
AB: In August of 2007, 19 consecutive days of PFISR radar coverage were obtained in a mode designed for the study of Polar Mesospheric Summer Echoes. This mode consisted of four beams within 10 degrees of vertical and one beam pointed vertically. Several of the days had simultaneous iron resonance and Raleigh lidar observations and all occurred during operation of the AIM (Aeronomy of Ice in the Mesosphere) satellite. PMSE was detected with the UHF PFISR system as early as May 24, 2007 [ Varney et al., 2007] and has also been studied using a 26-position imaging mode [ Nicolls et al., 2007]. Many examples of UHF PMSE were detected in all of these modes, the implication being that irregularities with scales of only .33 m are a common occurrence in PMSE. This is two orders of magnitude smaller than the inner scale of neutral turbulence. Since there seems to be little evidence in the data for aspect sensitivity of the echoes, turbulence must be rather isotropic at this scale. PMSE is generally a daytime phenomenon due to the need for ambient electrons to charge the ice particles and provide electrons for scattering targets. In this data set we find a number of nighttime events in the presence of aurorally enhanced D and E regions. The mode is suitable for spectral analysis, and the spectral widths will be presented in this talk.
DE: 2407 Auroral ionosphere (2704)
DE: 3332 Mesospheric dynamics
DE: 3379 Turbulence (4490)
DE: 6969 Remote sensing
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting