VARIATIONS IN FREE ATMOSPHERE TEMPERATURE IN THE NORTH POLAR REGION, 1959—2000

V. V. Maistrova, A. P. Nagurnyi, and I. I. Bolshakova

Trends in the mean air temperature over the north polar region (60—90ºN) are discovered that show the warming of the free polar atmosphere below 400 hPa and cooling above this level. The vertical gradient of temperature tends to increase at all atmospheric levels (850—50 hPa), which suggests a strengthening of the vertical instability of the north polar atmosphere.