But still missing are new pledges from 70 countries, including China, which currently produces the largest share of greenhouse gas emissions, as well as Saudi Arabia and India, both large economies with a significant climate footprint. Brazil, Mexico and Russia submitted new pledges that have weaker emissions targets than their previous ones.
All those pledges, taken together, are far short of what’s needed to limit global temperature rise to levels that would avert the worst impacts of warming, the report confirms. When it was reached in 2015, the Paris Agreement set a target of limiting average temperature rise compared with preindustrial levels to well below 2 degrees Celsius, or 3.6 degrees Fahrenheit, by the end of the century.
Since then, because of advances in research, the scientific consensus is that the rise needs to be limited to 1.5 degrees C; beyond that threshold, there is a far greater likelihood of devastating consequences, like widespread crop failures and collapse of the polar ice sheets. So far, global temperatures have risen about 1 degree C since the late 19th century.
For its part, the United States, which has produced the largest share of global emissions since the beginning of the industrial age, has pledged to cut its emissions by 50 percent to 52 percent below 2005 levels by the end of this decade, a target that is shy of the commitments of the European Union and Britain.
But it is already proving to be difficult, especially politically, and it remains to be seen whether Mr. Biden will be able to persuade members of Congress to support major climate legislation before he goes to the international climate talks in November.
At the White House meeting Friday, known as the Major Economies Forum on Energy and Climate, Mr. Biden implored the leaders of nine countries and the European Commission to act faster and more aggressively to slash greenhouse gases. He also announced that the United States and Europe have pledged to help reduce methane emissions 30 percent globally by 2030 and asked other nations to join that effort. Methane is the second most abundant greenhouse gas after carbon dioxide.
“I need to tell you the consequences of inaction,” Mr. Biden said.
Pointing to recent extreme weather events including hurricanes, floods and wildfires around the country, flooding across Germany and Belgium, fires raging in Australia and Russia, and a record temperature in the Arctic Circle, Mr. Biden told leaders: “We don’t have a lot of time.”