Jan 16, 2020 - Energy & Environment

The 2010s were officially the hottest decade on record

Residents defend a property from a bushfire at Hillsville near Taree, 350km north of Sydney
Residents defend a property from a bushfire at Hillsville near Taree, north of Sydney in Australia on Nov. 12. Photo: Peter Parks/AFP via Getty Images

It's official: Last year was the world's second hottest on record, and 2010-2019 was the hottest decade ever recorded.

Why it matters: The findings, published in two separate reports by NOAA and the British weather service the Met Office Wednesday, are in line with those of research group Berkeley Earth, revealed at the start of the year. It's yet more evidence of the long-term warming trend that stems from human-induced greenhouse gas emissions.

  • The Met Office notes in its report that the main contributor to warming over the past 170 years "is human influence on climate from increasing greenhouse gases in the atmosphere."
The world’s five warmest years have all occurred since 2015 with nine of the 10 warmest years occurring since 2005."
— NOAA statement

The big picture: NOAA notes that analysis by NASA scientists in a separate study just released concurred with its results and found the last decade was the hottest since records began in 1880.

Zoom in: In the United States, 2019 marked the hottest year for Alaska on record.

Zoom out: The average global temperature in 2019 was 1.71°F above the 20th-century average, according to NOAA. The only year to record a hotter global temperature was 2016 — just. That year was 0.07 of a degree Fahrenheit hotter than 2019.

  • "The annual global land and ocean temperature has increased at an average rate of +0.13°F per decade since 1880," NOAA said in its report. However, since 1981 the average rate of increase is more than twice that rate — plus 0.32°F.
  • "For the 21-year span that is considered a reasonable surrogate for pre-industrial conditions (1880–1900), the 2019 global land and ocean temperature was 2.07°F ... above the average," NOAA stated..

The bottom line: Per the Met Office, "The effects of human-induced climate change are not limited to surface temperature. Warming of the climate system is seen across a range of climate indicators that build a holistic picture of change outside of our expectations from natural variability across the land, atmosphere, oceans and ice."

Go deeper: 2010s to go down as hottest decade on record

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