GRL - Upper Atmosphere Cooling For 30 Yrs.; 1981-2013 Radar Temp Data Match Predicted Changes
Increasing amounts of greenhouse gases released by human activities do not just affect only the lower atmosphere: Scientists project that anthropogenic carbon emissions have caused a cooling trend in the upper atmosphere, between 200 and 400 kilometers, over the past few decades. Cooling in this atmospheric region can affect the operations of satellites and the orbits of space junk. However, data about cooling trends in the upper atmosphere are still incomplete, and better data are needed to confirm this projection.
Ogawa et al. present the first quantitative measurements that match projected upper
atmospheric cooling. The authors analyzed data from the European Incoherent Scatter radar, which studies the interactions between the Sun and Earth on the basis of disturbances in Earth’s ionosphere and magnetosphere.
From the radar’s raw data spanning from 1981 to 2013, the authors teased out information about changes in upper atmospheric temperature. They calculated a cooling trend of 10–15 kelvins per decade near altitudes of 220–380 kilometers and little to no cooling at 400 kilometers
EDIT
http://onlinelibrary.wiley.com/doi/10.1002/2014EO470008/pdf