Countries have made scant progress in curbing their greenhouse gas emissions over the past year, keeping the planet on track for dangerous levels of warming this century, according to a new report published Thursday.
The report by Climate Action Tracker, a research group, estimates that the climate and energy policies pursued by governments around the world would cause global temperatures to rise roughly 2.7 degrees Celsius, or 4.9 degrees Fahrenheit, above preindustrial levels by 2100.
That estimate of future warming has barely budged for three years now, the group said.
“We are clearly failing to bend the curve,” said Sofia Gonzales-Zuñiga, a climate policy specialist at Climate Analytics, a science and policy organization, and a lead author of the report. “As the world edges closer to these dangerous climate thresholds, the need for immediate, stronger action to reverse this trend becomes ever more urgent.”
The study was issued during the United Nations climate summit in Baku, Azerbaijan, where diplomats and world leaders have gathered to discuss how to raise trillions of dollars to cope with rising global temperatures.
Under the 2015 Paris Agreement, world leaders had pledged to hold total global warming to “well below” 2 degrees Celsius, and preferably closer to 1.5 degrees Celsius, to limit the risks from climate catastrophes. Scientists have said that every fraction of a degree of warming brings greater risks from deadly heat waves, wildfires, drought, storms and species extinction.
That more stringent target looks increasingly out of reach.
Every year, Climate Action Tracker scrutinizes all the climate policies that countries have enacted worldwide, such as regulations to curb pollution from power plants or to improve the efficiency of cars. They then estimate the effect of these policies on future greenhouse gas emissions and calculate how much of a temperature increase the world can expect.
Over the past three years, the United States has enacted the Inflation Reduction Act, which is expected to pour hundreds of billions of dollars into low-carbon technologies like wind, solar and nuclear energy, and carbon capture technology. China has been selling record numbers of electric vehicles. The European Union has ramped up its targets for renewable energy and heat pumps.
Yet the world is still heading for significant warming because global energy demand is growing faster than clean energy is expanding, which means fossil fuel use has been rising to fill the gap.
“Rising emissions while renewables boom is not a paradox,” said Niklas Höhne, a scientist with NewClimate Institute, which partners with Climate Action Tracker. “In recent years fossil fuels won the race against renewables, leading to increasing emissions.”
As part of global climate talks, many countries have formally pledged to zero out their emissions by around midcentury. If governments followed through, warming might be limited to roughly 2.1 degrees Celsius, the report said. But many countries have not backed up those lofty promises with concrete action.
Climate Action Tracker also tried to estimate the potential effects of Donald Trump’s return to the White House. He has promised to slash support for clean energy and electric vehicles while dismantling environmental regulations.
The authors calculated that a complete rollback of U.S. climate policies might add as much as a few tenths of a degree of warming by 2100. The effect would be relatively limited, in part because the United States accounts for just 13% of global emissions today.
On the other hand, if the Trump administration’s actions led other countries to weaken or abandon their climate policies, the effect might be far greater.
The study also calculated what countries would need to do to hold total warming closer to a long-term average of 1.5 degrees Celsius, as leaders have pledged. The United States would need to slash its emissions roughly 80% below 2005 levels by 2035. China would need to cut its emissions by two-thirds over the same time frame. India, Europe, Brazil, Japan and Australia would all have to make deeper cuts than they are currently planning.
This year, Earth will already be 1.5 degrees Celsius hotter than preindustrial levels, at least temporarily. At the climate talks in Baku, many world leaders have been reluctant to acknowledge that the world is overwhelmingly likely to exceed that threshold in the years ahead.
But some scientists have been speaking out.
“It is always possible to find arguments to make 1.5°C forever possible, but they increasingly diverge from reality,” wrote Glen Peters, a senior researcher at the CICERO Center for International Climate Research in Oslo, Norway, in a paper published this week. “It is time to admit that the world will cross 1.5°C.”
At the same time, Peters wrote, crossing that threshold “does not mean the world has failed.” Scientists have said that climate change risks increase with every fraction of a degree, so it will always be worthwhile to cut emissions as quickly as feasible to prevent further warming. But, he added, focusing on an unrealistic temperature limit “is no longer useful.”
“Crossing 1.5°C is not a time to give up,” he wrote, “but a time to acknowledge our failures and find a new hope moving forward.”