Type |
Journal Article |
Names |
S. M. Nossal, E. J. Mierkiewicz, F. L. Roesler, L. M. Haffner, R. Reynolds |
Publication |
AGU Fall Meeting Abstracts |
Volume |
51 |
Pages |
1608 |
Date |
December 1, 2010 |
URL |
http://adsabs.harvard.edu/abs/2010AGUFMSA51A1608N |
Library Catalog |
NASA ADS |
Abstract |
The University of Wisconsin has observed geocoronal hydrogen
Balmer-alpha emissions since the late 1970s from Wisconsin and during
Solar Cycle 23 from the Kitt Peak, AZ observatory. These observations
were all obtained using ground-based double etalon Fabry-Perot
Interferometers. The signal-to-noise of the observations has increased
along with the sensitivity of the instrumentation. Earlier observations
used scanning photomultiplier detection, and the Solar Cycle 23
observations employed CCD annular summing spectroscopy. We are using
this long-term data set to investigate the impact of the solar cycle
variation upon upper atmospheric hydrogen, a byproduct of radiatively
important water vapor and methane, below. The Wisconsin Northern
hemisphere mid-latitude data set shows consistent solar cycle dependence
over two solar cycles and three solar minima with column emission
intensities a factor of ~1.5 higher during solar maximum than solar
minimum conditions. We review the Wisconsin long-term data record and
present ongoing efforts to compare these observations to empirical and
climate models of the upper atmosphere through the use of forward
modeling. The observed trend of higher intensities during solar maximum
periods is consistent with predictions. However, there are significant
differences in magnitude between the predicted and observed intensities
and solar cycle variation. |
Tags |
[0310] ATMOSPHERIC COMPOSITION AND STRUCTURE / Airglow and aurora, [0328] ATMOSPHERIC COMPOSITION AND STRUCTURE / Exosphere, [0355] ATMOSPHERIC COMPOSITION AND STRUCTURE / Thermosphere: composition and chemistry |