Experimental results on some irregular phenomena in the thermosphere
Abstract
In about 60% of 182 density profiles between 100 and 200 km, taken from solar X-ray absorption measurements with the Solrad 9-satellite during sunset and sunrise, wavelike phenomena and/or a density hump have been observed. The density waves, with amplitudes up to 30%, are present over the whole height range. There are some indications that they are due to gravity waves propagated from below and related to weather phenomena in the troposphere. The density hump seems to be a quite separate feature and limited to a narrow height interval around 200 km. The hump is most frequently observed during sunset and during winter, its amplitude reaching 150% above normal local gas density. It is interpreted in terms of a density bulge, limited in height, caused by the absorption of solar EUV-radiation and asymmetric in shape between sunrise and sunset.
- Publication:
-
Journal of Atmospheric and Terrestrial Physics
- Pub Date:
- January 1975
- DOI:
- 10.1016/0021-9169(75)90087-2
- Bibcode:
- 1975JATP...37...31K
- Keywords:
-
- Atmospheric Density;
- Density Distribution;
- Electromagnetic Absorption;
- Solar X-Rays;
- Thermosphere;
- Explorer 37 Satellite;
- Far Ultraviolet Radiation;
- Gas Density;
- Gravity Waves;
- Night Sky;
- Satellite Observation;
- Solar Radiation