Notes concerning the maps:
The number at the top right-hand corner is an estimate for the global mean. Missing data are replaced by the zonal mean to find that estimate. However, if the map only shows ocean data, the mean is computed only over the area with data (added 12/13/2010). The end points of the color bar are either -4.1 or +4.1 or the minimum or maximum value of the data if it is outside that range.