Upper atmosphere cooling over the past 33 years
2014 (English)In: Geophysical Research Letters, ISSN 0094-8276, Vol. 41, no 15, 5629-5635 p.Article in journal (Refereed) Published
Theoretical models and observations have suggested that the increasing greenhouse gas concentration in the troposphere causes the upper atmosphere to cool and contract. However, our understanding of the long-term trends in the upper atmosphere is still quite incomplete, due to a limited amount of available and well-calibrated data. The European Incoherent Scatter radar has gathered data in the polar ionosphere above TromsO for over 33years. Using this long-term data set, we have estimated the first significant trends of ion temperature at altitudes between 200 and 450km. The estimated trends indicate a cooling of 10-15K/decade near the F region peak (220-380km altitude), whereas above 400km the trend is nearly zero or even warming. The height profiles of the observed trends are close to those predicted by recent atmospheric general circulation models. Our results are the first quantitative confirmation of the simulations and of the qualitative expectations.
Place, publisher, year, edition, pages
2014. Vol. 41, no 15, 5629-5635 p.
EISCAT, global warming, thermosphere, temperature, upper atmosphere
Meteorology and Atmospheric Sciences Physical Sciences
IdentifiersURN: urn:nbn:se:uu:diva-234201DOI: 10.1002/2014GL060591ISI: 000341725200040OAI: oai:DiVA.org:uu-234201DiVA: diva2:758599