Energy content over high latitudes of Northern Hemisphere

The GDAAC monthly mean data set of temperature, zonal and meridional winds at 18 pressure levels from 1000 to 20 hPa for 1980-1993 period was used as initial for calculations of zonal mean kinetic (KM), eddy kinetic (KE) and eddy available potential (PE) energies. The offered by Plumb energy cycle formulation is assumed as a basis. The calculations were carried out for latitudinal belt between 60 N and 90 N.

Mean values of KM, KE and PE over high latitudes of the Northern Hemisphere are 1.17, 0.34 and 1.12 10⁶ Jm^-2 respectively. The integral values of KE and KM content are smoothly decreasing poleward and are almost zero near Northern Pole whereas PE content has sharp diminution from 3.16 at 62 N to 0.7 10⁶ Jm^-2 at 68 N. At that the main contents of KM and KE are concentrate near 300 hPa level in the 60-65 N latitudinal belt (5.78 and 1.22 10⁵ Jm^-2) but PE content has two maximums in that region – in the stratosphere (4.09 10⁵ Jm^-2) and in the boundary layer (10.76 10⁵ Jm^-2). Maximal contents of KM, KE and PE are observed in winter and in summer are some times as less.

The carried out analysis has shown that the energy conversion in the high latitudes has seasonal variability. At that in winter the most intensive processes are assigned with Ferrel cell but its effect extend to 70-75 N only.