Based on ECMWF analyses and forecasts for stratospheric levels, we provide maps of geopotential and temperature on pressure levels, potential vorticity on isentropic levels, and zonal sections for the northern hemisphere. In addition to that we provide time series of derived quantities during the Arctic winter from 01 November - 30 April.

The analyses of the stratospheric fields discontinued in June 2001. All available Data, daily and monthly mean analyses as well as climatological averages, are included on a CD and are now available. Plots of daily stratospheric data can be derived online.

Daily radiosonde soundings of the winds in the equatorial stratosphere were used to derive the time series of the Quasi-Biennial Oscillation (QBO).  It is compiled by Barbara Naujokat since 1953 as monthly mean values on levels between 100 and 10 hPa.

The 30 hPa North Pole temperatures during the Arctic Winter are tabulated since 1955/56. The occurrences of Major-Midwinter-Warmings, and Canadian Warmings, and the timing of the Final Warmings are documented together with the  sunspot numbers and the phase of the QBO.