About this datasetThese maps depict how much warmer or colder a region may be in a given month compared to the norm for that same month in the same region from 1951-1980. These maps do not depict absolute temperature but instead show temperature anomalies, or how much it has changed.
What do the colors mean?
Shades of red and orange indicate areas where the average monthly temperatures are warmer than they were in that area during the base period from 1951-1980. Shades of blue show cooling compared to the base period. So if New England is red in a March of a given year, then it is warmer than the average March in New England from 1951-1980. If part of Canada is blue in August, then it is cooler than the average for August during the base period. Black areas are where no data are available.
The source data for these images is 2x2 degrees — or 180x90 pixels. Therefore, the images need to be significantly upscaled in order to be useful on most displays.
Hansen, J., R. Ruedy, M. Sato, and K. Lo (2010). Global surface temperature change. Reviews of Geophysics.
National Academy of Sciences (2010). Advancing the Science of Climate Change.
NASA Earth Observatory (2010). Global Warming
NASA Earth Observatory (2010). World of Change: Global Temperature Record.
Imagery by Kevin Ward, NASA Earth Observatory based on data provided by the NASA Goddard Institute for Space Studies (GISS).
Federal Geographic Data Committee Geospatial Metadata
View the FGDC Metatdata for Global Temperature Anomaly (1 month)