Greenhouse Cooling of the Upper Atmosphere
Observed in High-Latitude Ionosonde Data
Thomas Ulich(1,2) and Esa Turunen(1)
(1)Geophysical Observatory, FIN-99600 Sodankylä, Finland
(2)Dept. of Physical Sciences, University of Oulu, FIN-90570 Oulu,
Increased concentrations of greenhouse gases in the air cause a cooling of
the strato-, meso-, and thermosphere (Roble and Dickinson, 1989); the
atmosphere is expected to shrink. Rishbeth (1990) predicted a lowering of
the peak height of the ionospheric F2-layer which was confirmed for
mid-latitudes by Bremer (1992). In the present study we compare long-term
data from Sodankylä, Finland, (high latitude, 67.4N, 26.7E) with
Bremer's results and another ionosonde record of lower latitudes. In all
data we observe cooling of the upper atmosphere.
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and thermosphere?, Geophys. Res. Lett. 16, 1441-1444.
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- Bremer, J. (1992) Ionospheric trends in mid-latitudes as a possible
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