What does this mean?

The map and bar graph show how air temperatures in the Arctic compare to averages from 1979 to 2012. On the map, areas with higher than average temperatures for the selected month and year are indicated in oranges and reds (positive anomalies), and areas with lower than average temperatures are shown in blues (negative anomalies). These are temperatures two meters above the surface, similar to the temperatures given in weather reports and forecasts.

The bar graph indicates the average temperature anomaly for the selected month and year, for the entire Arctic (the area north of 60°N). Continue reading...