There was a “relentless” intensification of the climate crisis in 2020, according to the UN’s World Meteorological Organization.
The coronavirus pandemic made the accelerating impacts of global heating even worse for millions of people. But the temporary dip in carbon emissions due to lockdowns had no discernible impact on atmospheric concentrations of greenhouse gases, the WMO report said.
Last year was ranked as the hottest on record, in a tie with 2016 and 2019, despite the cooling effect of the cyclical natural climate phenomenon, La Niña. Without this, 2020 would most likely have been the hottest year yet. The decade 2011-20 was the hottest on record.
Extreme weather events broke records across the world, from hurricanes and cyclones in the US and India, heatwaves in Australia and the Arctic, floods in large parts of Africa and Asia, and wildfires in the US.
“All the key climate and impacts information in this report highlight relentless, continuing climate change, an increasing occurrence and intensification of extreme events, and severe losses and damage, affecting people, societies and economies,” said Petteri Taalas, the WMO secretary general.
The WMO’s State of the Climate report comes just before a global leaders’ summit, convened by the US president, Joe Biden, and as the UK prepares to host the crucial Cop26 UN climate summit in November, at which urgent action must be agreed to meet the goals of the 2015 Paris agreement, to keep the global temperature increase to well below 2C and 1.5C if possible. In 2020, the temperature was 1.2C above pre-industrial levels.
“This is the year for action,” said the UN head, António Guterres. “The climate is changing, and the impacts are already too costly for people and the planet. Countries need to submit, well ahead of Cop26, ambitious plans to cut global emissions by 45% by 2030.”
The report, produced by the WMO and partners, found that cuts in food production, transport and economic activity caused by the Covid-19 pandemic exacerbated the effects of extreme weather on communities. It said the temporary fall in new carbon emissions had “no discernible impact” on atmospheric concentrations.
The report also found that in 2020:
80% of the oceans experienced at least one marine heatwave, while record heat accumulated in the seas, which absorb 90% of heat resulting from human activities.
Sea ice in the Arctic reached its second lowest minimum on record, while hundreds of billions of tonnes of ice were lost in Greenland and Antarctica, helping to push up sea level.
Severe flooding hit large parts of Africa and Asia, helping trigger a locust plague in the Horn of Africa.
Extreme drought affected many parts of South America in 2020, with the estimated farming losses near $3bn in Brazil alone, with further losses in Argentina, Uruguay and Paraguay.
The largest wildfires ever recorded burned in the US, while Australia broke heat records, including a temperature of 48.9°C in western Sydney.
The north Atlantic hurricane season had its largest number of named storms on record with 30, and a record 12 made landfall in the US.
Cyclone Amphan hit India and Bangladesh and was the costliest tropical cyclone on record for the north Indian Ocean, while Typhoon Goni which crossed the Philippines was one of the most intense cyclones ever to hit land.
Richard Allan, a professor of climate science at the University of Reading in the UK, said: “What is notable is an emerging picture that climate change is gathering pace: [ice is] melting more quickly and heat is accumulating more rapidly in the ocean, while CO2 increases, which are driving these changes, are becoming progressively larger over time.”
Prof Chris Rapley, at University College London, UK, said: “The 1.5C Paris guard-rail is close to being breached. The way we are running human affairs is destabilising the climate system, with predictable and increasingly dire consequences. It’s time for an uprising of concerted action to fix politics – managing the climate crisis will follow.”