The relentless challenge of global warming has been underscored once again by the tally of the past year, with 2022 regarded as one of the warmest years on record and the past eight years combined now being the hottest documented by modern science.
Last year’s average global temperature was about 1.15C warmer than the pre-industrial era, according to the World Meteorological Organization (WMO), with record-breaking scorching heat blanketing much of Europe and Asia, both of which experienced their second-hottest years on record. Europe had its warmest summer ever.
The cooling influence of La Niña, a periodic climate event now in its third year leading to higher temperatures in parts of the world, helped moderate some of the heat in 2022, with the year being ranked as either the fifth or sixth hottest year on record.
Line graph of six data sets tracking global mean temperature anomalies from an 1850 to 1900 average. Photo: World Meteorological OrganizationThe WMO uses six different datasets, including that of NASA, which was the fifth hottest in the 143-year record last year, and the US National Oceanic and Atmospheric Administration (NOAA), which revised the year due to minor differences in sixth place for data collection.
The long-term trend is clear, however, as the eight hottest years on record have all occurred since 2015, with 2016 still being the hottest of them all, and each decade since the 1980s has been progressively hotter than the last. The 10 hottest years have all occurred since 2010.
Bill Nelson, NASA Administrator, said the warming trend is “quite alarming, and it’s a trend that’s growing in magnitude.
“If we don’t take this seriously, there will be deadly repercussions around the world. Extreme weather patterns threaten our well-being around the world and we need bold action.”
More of the same looms in the coming year, with the WMO warning that conditions in La Niña are likely to ease after March, removing the ameliorating cooling effect of warming caused by humanity’s continued burning of fossil fuels.
The rising heat bodes the kind of climate-related disasters that punctuated 2022, including floods that engulfed about a third of Pakistan, a record heatwave that scorched China and wildfires that scorched across Europe and North America. Heat and the accompanying drought helped uncover sunken battleships and bombs in dried-up European rivers and human bodies in stricken US reservoirs.
“In 2022, we faced several dramatic weather disasters that claimed far too many lives and livelihoods and undermined health, food, energy and water security and infrastructure,” said Petteri Taalas, Secretary-General of the WMO, adding that an ongoing Drought in the Horn of Africa threatens “a humanitarian catastrophe”.
The opening stanza of 2023 has already hit much of Europe with exceptional heat, while California has been repeatedly inundated by the kind of flooding scientists warn is being exacerbated by the climate crisis.
The assessment of last year’s increased heat — 2022 was the 46th consecutive year with temperatures above 20th-century averages — includes millions of atmospheric and marine temperature records, as well as a health check of Earth’s other vital signs.
The map shows that in 2022 most of the Earth was warmer than the pre-industrial average. Photo: NoaaAverage annual sea ice extent in the Arctic was the 11th smallest in a record dating back to 1979, with the 10 lowest Arctic sea ice extents all occurring since 2007, while annual sea ice extent around Antarctica was the second lowest, only surpassed by the record from 1987.
Most of the heat trapped by greenhouse gas emissions goes straight to the oceans, which had a record year for heat in 2022, a recent study found. The steep rise in sea temperatures is a clearer and better predictor of the climate crisis than atmospheric temperatures, which can be affected from year to year by variables like the La Niña effect, according to Michael Mann, a climate scientist at the University of Pennsylvania.
“A few years ago we showed that as long as we keep warming the planet, we expect the series of record breakers to continue, but with these kinds of temporary breaks due to natural fluctuations,” he said. “So what we’re seeing here is what we’re expecting.”
Rachel Licker, a climate scientist at the Union of Concerned Scientists, said rising temperatures should spur US and global policymakers to do far more to reduce emissions from the planet’s warming.
“Rather than give in to the interests of the fossil fuel industry aimed at increasing their profits, we need strong leaders willing to implement bold climate policies for the benefit of people and the planet,” she said.
“Politicians who hesitate to move beyond incrementalism and greenwashing companies are openly stealing the future that rightfully belongs to our children. The science is unanimous: large-scale, transformative action is the only way forward.”