Last month was 1.1 degrees Celsius warmer than the mean February temperature from 1951-1980. The two top February temperature anomalies have occurred during the past two years.
February 2016 was the hottest on record, at 1.3 degrees Celsius warmer than the February mean temperature. February 2017's temperature was 0.20 degrees Celsius cooler than February 2016.
The monthly analysis by the GISS team is assembled from publicly available data acquired by about 6,300 meteorological stations around the world, ship- and buoy-based instruments measuring sea surface temperature, and Antarctic research stations.
The modern global temperature record begins around 1880 because previous observations didn't cover enough of the planet. Monthly analyses are sometimes updated when additional data becomes available, and the results are subject to change.