he year 2014 now ranks as the warmest on record since 1880, according to an analysis by NASA scientists.
This video shows a time series of five-year global temperature averages, mapped from 1880 to 2014, as estimated by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York.
While scientists expect temperatures to fluctuate from year to year, the average temperature of the planet as a whole has warmed by about 1.4 degrees Fahrenheit (0.8 degrees Celsius) since 1880. This trend is largely driven by increasing human emissions of carbon dioxide and other greenhouse gases into the atmosphere.
The GISS analysis incorporates temperature measurements from 6,300 weather stations around the world, ship- and buoy-based ocean temperature readings and data from Antarctic research stations. These measurements are plugged into an algorithm that then estimates average global temperature. The computer code for this process is freely available for download from the GISS web site.
