Historic heat in north America in March 2012 – big picture

The unseasonable warmth broke temperature records in more than 1,054 locations between 13-19 March. The intensity and scope of the heat wave is clearly visible in this map of land surface temperature anomalies. The map depicts temperatures compared with the average of the same eight day period of March from 2000-2011. Areas with warmer than average temperatures are shown in red, near-normal temperatures are white, and areas that were cooler than the 2000-2011 base period are blue. Photograph: Terra/MODIS/Nasa Illustration: Terra/MODIS/NASA