Shown are zonal mean time series of zonal mean temperature and eastward wind calculated with the ECMWF global weather forecast model for 1979 onward.
They are based on 2.5x2.5 degree daily (12 h UT) analyses on pressure levels, either from the ERA Interim (EI) reanalysis (1979-2008) and from operational analyses (OD) thereafter.
The first 10 years of EI are yellow, the second 10 years from EI are lightblue, and the third 10 years form EI are orange. The operational analyses from 2009 onward have varying colours. The red line is the current year (2012).
The temperature is expressed in degrees K(elvin) = degrees C(elsius) + 273
| Temperature | Eastward wind | |
|---|---|---|
| Northern Hemisphere | T 50 hPa North Pole | v 60 N 10 hPa |
| Southern Hemisphere | T 50 hPa South Pole | v 60 S 10 hPa |
