2021 was the sixth hottest year on record, US studies say
January 14, 2022The year 2021 was the sixth warmest year on record, according to an analysis of global temperature released on Thursday by two US government agencies.
The latest data, compiled by NASA and the National Oceanic and Atmospheric Administration (NOAA), underscores the global climate crisis.
2021 tied with 2018 for sixth warmest, according to NASA, which uses a 30-year baseline period.
A separate analysis by NOAA showed 2021 average temperatures were 1.51 degrees Fahrenheit (0.84 Celsius) above the 20th-century average, putting last year in sixth place by itself, ahead of 2018.
This is part of a long-term warming trend that shows signs of accelerating, officials said.
Hottest decade
The data showed that the nine years spanning 2013-2021 all rank among the 10 hottest since record-keeping began in 1880.
"It's certainly warmer now than at any time in at least the past 2,000 years, and probably much longer," said Russell Vose, chief of climate monitoring for the NOAA.
"Of course, all this is driven by increasing concentrations of heat-trapping gases like carbon dioxide," he said, adding that 2022 would almost certainly rank among the top 10 hottest years.
"There's probably a 99 percent chance that 2022 will rank in the top 10, a 50-50 chance, maybe a little less, it'll rank in the top five, and a 10 percent chance it'll rank first" barring an unforeseen event like a major volcanic eruption or a large comet hitting Earth, Vose said.
Warm temperatures despite La Nina
Last year, global temperatures were dampened by the presence of La Nina in the eastern Pacific Ocean.
The La Nina phenomenon is the natural cooling of parts of the central Pacific that changes weather patterns globally and brings chilly deep ocean water to the surface.
It is the colder counterpart of the El Nino climate pattern which boosted global temperatures in 2016.
Climate scientists said 2021 was the hottest La Nina year on record.
The year did not represent a cooling off of human-caused climate change but provided more of the same heat.
"It's not quite as headline-dominating as being the warmest on record but give it another few years and we'll see another one of those" records, said climate scientist Zeke Hausfather of the Berkeley Earth monitoring group which also ranked 2021 the sixth hottest.
"It's the long-term trend, and it's an indomitable march upward."
Planet may hit 1.5C by 2030s
The rising temperatures are largely the result of increases in the abundance of atmospheric greenhouse gases since the industrial revolution, which is mainly the result of human activity.
Scientists believe that at the current rate, the planet's temperature would rise by 1.5C above pre-industrial levels in the 2030s.
"But it's not the case that at 1.4 everything is hunky-dory and at 1.6 all hell has broken loose," said NASA climate expert Gavin Schmidt.
adi/wd (AFP, AP, Reuters)