Risk level rises for Earth if U.S. retreats: experts
WASHINGTON — Earth is likely to reach more dangerous levels of warming even sooner if the U.S. retreats from its pledge to cut carbon dioxide pollution, scientists said. That’s because America contributes so much to rising temperatures.
U.S. President Donald Trump, who once proclaimed global warming a Chinese hoax, said in a tweet Saturday that he would make his “final decision” this coming week on whether the United States stays in or leaves the 2015 Paris climate change accord in which nearly every nation agreed to curb its greenhouse gas emissions.
Leaders of seven wealthy democracies, at a summit in Sicily, urged Trump to commit his administration to the agreement, but said in their closing statement that the U.S., for now, “is not in a position to join the consensus.”
“I hope they decide in the right way,” said Italy’s prime minister, Paolo Gentiloni. More downbeat was German Chancellor Angela Merkel, who said the leaders’ talks were “very difficult, if not to say, very unsatisfactory.”
In an attempt to understand what could happen to the planet if the U.S. pulls out of Paris, the Associated Press consulted with more than two dozen climate scientists and analyzed a special computer model scenario designed to calculate potential effects.
Scientists said it would worsen an already bad problem and make it far more difficult to prevent crossing a dangerous global temperature threshold.
Calculations suggest it could result in emissions of up to three billion tonnes of additional carbon dioxide in the air a year. When it adds up year after year, scientists said that is enough to melt ice sheets faster, raise seas higher and trigger more extreme weather.
“If we lag, the noose tightens,” said Princeton University climate scientist Michael Oppenheimer, co-editor of the peer-reviewed journal Climatic Change.
One expert group ran a worst-case computer simulation of what would happen if the U.S. does not curb emissions, but other nations do meet their targets. It found that America would add as much as 0.3 C warming to the globe by the end of century.
Scientists are split on how reasonable and likely that scenario is.
Many said because of cheap natural gas that displaces coal and growing adoption of renewable energy sources, it is unlikely that the U.S. would stop reducing its carbon pollution even if it abandoned the accord, so the effect would likely be smaller. Others say it could be worse because other countries might follow a U.S. exit, leading to more emissions from both the U.S. and the rest.
Another computer simulation team put the effect of the U.S. pulling out somewhere between 0.1 C to 0.2 C.
While scientists may disagree on the computer simulations, they overwhelmingly agreed that the warming the planet is undergoing now would be faster and more intense.
The world without U.S. efforts would have a far more difficult time avoiding a dangerous threshold: keeping the planet from warming more than 2 C above preindustrial levels.
The world has already warmed by just over half that amount — with about onefifth of the past heat-trapping carbon dioxide emissions coming from the United States, usually from the burning of coal, oil and gas. So the efforts are really about preventing another 0.9 C from now.
“Developed nations — particularly the U.S. and Europe — are responsible for the lion’s share of past emissions, with China now playing a major role,” said Rutgers University climate scientist Jennifer Francis. “This means Americans have caused a large fraction of the warming.”
Even with the U.S. doing what it promised under the Paris agreement, the world is likely to pass that 2 C mark, many scientists said.
TAORMINA, Italy — Seven wealthy democracies ended their summit Saturday in Italy without unanimous agreement on climate change, as the Trump administration plans to take more time to say whether the U.S. is going to remain in the Paris accord on limiting greenhouse gas emissions.
The other six nations in the Group of Seven agreed to stick with their commitment to implement the 2015 Paris deal that aims to slow down global warming.
The final G-7 statement, issued after two days of talks in the seaside town of Taormina, said the U.S. “is in the process of reviewing its policies on climate change and on the Paris agreement and thus is not in a position to join the consensus on these topics.”
Trump tweeted he would decide on Paris this coming week. The announcement on the final day of the U.S. president’s first international trip comes after he declined to commit to staying in the sweeping climate deal, resisting intense international pressure from his peers at the summit.
French President Emmanuel Macron also chimed in on the climate issue, praising Trump’s “capacity to listen.”
Macron said he told Trump it is “indispensable for the reputation of the United States and the interest of the Americans themselves that the United States remain committed” to the Paris climate agreement.
Trump held no news conferences during his nine-day overseas trip, allowing him to avoid questions about investigations into his campaign’s ties with Russian officials. His top economic and national security advisers refused to answer questions during a press briefing Saturday.
The G-7 leaders had better luck finding agreement on the other problematic topic at the summit, trade.
They restored a vow to fight protectionism — the use of import taxes and skewed regulations that favour domestic producers over their foreign competitors. The no-protectionism pledge had been a part of previous G-7 statements but was omitted after a meeting of the group’s finance ministers’ this month in Bari, Italy. This time the G-7 leaders reiterated a “commitment to keep our markets open and to fight protectionism.”
The Trump administration has argued that trade must be balanced and fair as well as free. U.S. Treasury Secretary Steven Mnuchin has said the United States reserves the right to be protectionist if trade arrangements are unfair to U.S. companies and workers.
Trump’s position appeared to be addressed by new language that said the member countries would be “standing firm against all unfair trade practices.”
Japanese Prime Minister Shinzo Abe said the G-7 also agreed to step up pressure on North Korea, including sanctions. He told reporters it was the first time that the G-7 had recognized the North Korean threat as a priority issue.
“The threat has entered a new stage (as North Korea tests missiles and nuclear weapons) … there is a danger it can spread like a contagious disease,” Abe said.
The leaders also agreed on two other topics: closer co-operation against terrorism in the wake of the concert bombing in Manchester that killed 22 people, and on the possibility of putting more sanctions against Russia over its conflict with Ukraine if Russian behaviour requires that.