2020 was officially one of the warmest years on record, a sign of relentless global warming, according to a handful of analyzes published by scientists around the world over the past week.
The heat record comes after a year punctuated by climatic catastrophes: historic heat waves, hurricanes and forest fires.
“This is a clear indication that the global signal of human-induced climate change is now as powerful as the force of nature,” Petteri Taalas, secretary general of the World Meteorological Organization, said in a statement.
Analyzes disagree on whether 2020 was the hottest year on record. A NASA report released on Thursday found that 2020 narrowly beat 2016 the hottest year of all time, effectively tie the record. Another analysis, published Thursday by the National Oceanic and Atmospheric Administration, concluded that 2020 was a close second to 2016. And last week, the European Union’s Copernicus Climate Change service determined 2020 tied with 2016 like the hottest year.
The conclusions differ slightly because research groups apply various techniques to piece together a global picture of temperatures based on temperature observations from thousands of weather stations.
The 2020 heat record is just the latest in a series of years with more heat.
“The past seven years have been the hottest seven years on record,” said NASA researcher Lesley Ott. So no matter where the individual years fall, “the consistency of the most recent years being the hottest on record is very, very clear,” she said.
For all of these analyzes, “the difference between 2020 and 2016 is less than the uncertainty of the record,” Zeke Hausfather, a climatologist with independent research group Berkeley Earth, told BuzzFeed News via email. “So it is indeed a tie for the hottest.”
The year 2020 was marked by searing heat for most of the year, dulled towards the end by the natural cooling phenomenon, La Niña.
“The exceptional heat of 2020 is despite a La Niña event, which has a temporary cooling effect,” Taalas said.
Climate change has led to other major heat records in 2020.
Siberia experienced a multi-month heat wave, and the arctic city of Verkhoyansk recorded its hottest day on record, reaching 100 degrees Fahrenheit on June 20. concluded.
2020 was the hottest year on record in Europe, with 1.6 degrees Celsius above the average temperature from 1981 to 2010, according to Copernicus analysis. 2019 previously held this record, where observed temperatures were 0.4 degrees Celsius higher than at the same time.
Last year also marked the busiest hurricane season in the Atlantic Ocean, as well as a history devastating series of wildfires in the western United States. The result was that the United States most billion dollar disasters in 2020. The year also started with some of the the worst bushfires in Australian history. Additionally, carbon dioxide levels in the atmosphere continued to rise, reaching a new high of 413 parts per million last May.
Meanwhile, the pandemic triggered an economic shock that caused US emissions are expected to fall by around 10.3% in 2020, according to a preliminary analysis by the research organization Rhodium Group, which is part of a declining trend in emissions worldwide last year. But a brief drop in emissions will not be enough to curb the global warming trend – which will require long-term emission reductions.
“The vast majority of the warming we see is due to human greenhouse gas emissions,” Ott said.