Regular ionosonde observations from Tromso (69degreesN 19degreesE) date from 1935 and the dataset thus represents one of the longest in existence. Trends in the critical frequency of the ionospheric F2 layer are determined and found to be negative. Our results lend support to a causative mechanism which includes greenhouse cooling.
|Journal||Geophysical Research Letters|
|Publication status||Published - 2002|