Southern hemisphere observations of a long-term decrease in F region altitude and thermospheric wind providing possible evidence for global thermospheric cooling
F region peak heights, derived from ionospheric scaled parameters through 38-year data series from both Argentine Islands (65°S, 64°W) and Port Stanley (52°S, 58°W) have been analyzed for signatures of secular change. Long-term changes in altitude, which vary with month and time of day, were found a...
| Published in: | Journal of Geophysical Research: Space Physics |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
American Geophysical Union
1998
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| Subjects: | |
| Online Access: | http://nora.nerc.ac.uk/id/eprint/504096/ https://doi.org/10.1029/98JA01629 |
| Summary: | F region peak heights, derived from ionospheric scaled parameters through 38-year data series from both Argentine Islands (65°S, 64°W) and Port Stanley (52°S, 58°W) have been analyzed for signatures of secular change. Long-term changes in altitude, which vary with month and time of day, were found at both sites. The results can be interpreted either as a constant decrease in altitude combined with a decreasing thermospheric wind effect or as a constant decrease in altitude which is altitude-dependent. Both interpretations leave inconsistencies when the results from the two sites are compared. The estimated long-term decrease in altitude is of a similar order of magnitude to that which has been predicted to result in the thermosphere from anthropogenic change related to greenhouse gases. Other possibilities should not, however, be ruled out. |
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