The world lost a Netherlands-sized area of mature tropical forests in 2020, the second year in a row of worsening losses, according to the latest figures from the research and advocacy organization the World Resources Institute (WRI).
The losses are helping drive climate change and also being driven by it, as hot, dry conditions contribute to forest losses in several parts of the world.
Some bright spots emerged. The rate of forest loss decreased in Indonesia and Malaysia for the fourth consecutive year.
But overall, the 4.2 million hectare loss of primary, undisturbed forest was a 12% increase over 2019.
"Those dense forests can be hundreds of years old and store significant amounts of carbon," said Rod Taylor, head of WRI's forest program. "Losing them has irreversible impacts on biodiversity and climate change."
While experts had raised concerns that the economic impact of the COVID-19 pandemic could contribute to forest losses by reducing environmental enforcement and driving more people to subsistence farming, Taylor said there were no obvious trends in the data.
The impacts may come later, however.
"Unless we offer alternatives, it's likely that governments will try to restart their economies on the backs of forests," said WRI Distinguished Senior Fellow Frances Seymour.
The tropics lost a total of 12.2 million hectares of primary and secondary regrown forest in 2020, WRI's data said. The losses released the equivalent of the annual emissions from 570 million cars, more than twice the number on the road in the United States.
Brazil saw the largest decline. The 1.7 million hectares lost was a 25% increase from the previous year and more than three times the next-highest country, the Democratic Republic of Congo (DRC).
Bolivia was third. As in Brazil, much of the loss was due to fires set to clear land for agriculture, but which burned out of control due to hot, dry conditions.
In a rare bit of good news, Indonesia slowed its rate of loss by 17% in 2020, dropping out of third place and into fourth for the first time in the 20 years that WRI has been keeping records.
Wetter weather and lower prices for palm oil, the commodity driving deforestation, likely played a role.
But following devastating fires in 2015, the government also put measures in place that are contributing, experts say. Those include fire monitoring and prevention, restrictions on new palm oil plantations and agrarian reforms aimed at alleviating poverty.
Palm oil prices have rebounded, which may put pressure on the industry to expand again, said Sustainable Commodities and Business Manager Andika Putraditama in WRI's Indonesia office.
"The next two to three years would be the real test if Indonesia can maintain its performance in reducing deforestation," he said.
Climate change, cause and effect
While deforestation is a leading contributor to climate change, "the most ominous signal from the 2020 data is the number and variety of instances where forests themselves have fallen victim to climate change," Seymour said.
Hot, dry weather in 2019 and 2020 drove bark beetle damage in Germany and the Czech Republic, tripling forest losses compared to 2018.
Extreme heat and drought drove Australia's devastating fires in 2019 and 2020. Tree cover loss increased nine-fold between 2018 and 2020. Climate change is likely to make these conditions more common.
An abnormally hot spring and summer in Russia led to fires in Siberia's forests, and in peatlands that are normally frozen.
"Nature has been whispering this risk to us for a long time. But now she is shouting," Seymour said.
"We're getting into a vicious cycle," she added. "Climate change and forest degradation combine to make the forests that remain warmer, drier and more vulnerable to fire and pest infestations, which in turn releases more carbon when those forests burn and decay."
The longer it takes to stop deforestation and cut greenhouse gas emissions, Seymour said, "the more likely it is that our natural carbon sinks will go up in smoke."