| Type |
Journal Article |
| Names |
S. M. Nossal, E. J. Mierkiewicz, F. L. Roesler, L. M. Haffner, R. J. Reynolds, R. C. Woodward |
| Publication |
AGU Spring Meeting Abstracts |
| Volume |
14 |
| Pages |
01 |
| Date |
May 1, 2009 |
| URL |
http://adsabs.harvard.edu/abs/2009AGUSMSA14A..01N |
| Library Catalog |
NASA ADS |
| Abstract |
Hydrogen is a primary constituent of the geocorona and is a chemical
byproduct of species below such as methane and water vapor, two
greenhouse gases. The solar cycle is a dominant source of natural
variability in this region and must be accounted for when isolating the
effects of coupling processes from below, including that due to
potential long-term change in the region. Observations by the Wisconsin
H-alpha Mapper Fabry- Perot of geocoronal hydrogen Balmer-alpha
emissions over solar cycle 23 have quantified a factor of 1.5 ±
0.15 higher intensities at solar maximum than at solar minimum. These
observations are consistent with Fabry-Perot observations from Wisconsin
during solar cycle 22. All observations have been consistently
calibrated for intensity using the North American Nebula. We used the
LYAO_RT radiative transfer code of Bishop to compare the observed
Balmer-alpha intensities with intensities calculated using the hydrogen
density distribution in the Mass-Spectrometer-Incoherent-Scatter (MSIS)
model, a major empirical model used by the middle and upper atmospheric
research communities. The MSIS distribution yields a solar maximum to
minimum ratio similar to that observed; however, significant differences
in magnitude between predicted and observed intensities highlight the
need for improved upper atmospheric hydrogen density determinations. |
| Tags |
0310 Airglow and aurora, 0328 Exosphere, 0355 Thermosphere: composition and chemistry, 1620, 3305, 3309 Climatology (1616, 4215, 8408) |