WASHINGTON — Last year wasn't just the Earth's hottest year on record, federal scientists say — it left a century of high temperature marks in the dust.
The National Oceanic Atmospheric Administration and NASA announced Wednesday that 2015 was by far the hottest year in 136 years of record keeping.
NOAA said 2015's globally averaged temperature was 58.62 degrees Fahrenheit (14.79 degrees Celsius), passing 2014 by a record margin of 0.29 degrees. That's 1.62 degrees above the 20th century average. NASA, which measures differently, said 2015 was 0.23 degrees warmer than the record set in 2014.
Because of the wide margin over 2014, NASA calculated that 2015 was a record with 94 percent certainty, about double the certainty it had last year when announcing 2014 as a record.
Although 2015 is now the hottest on record, it was the fourth time in 11 years that Earth broke annual marks for high temperature.