A breakthrough in the quest for quick ratification came this month when the European Union, which represents about 10 percent of global warming emissions, set an Oct. 9 vote to join the agreement, with or without action by its member states. The bloc has pledged under the Paris agreement to cut its emissions 40 percent from 1990 levels by 2030, but not all of its 28 member states are yet prepared to approve their individual climate pledges. 
 
 That push gained unexpected momentum on Tuesday when President Andrzej Duda of Poland declared before the General Assembly that he expected his government to legally join the deal this year. It had been widely expected that Poland, one of Europe’s heaviest coal polluters, would object to the broader European body’s effort to move forward without all of its member states. 
 
 “What is important is the heritage that we leave to our children and grandchildren — how they will remember us, and how they will write about us in the history books,” Mr. Duda said. 
 
 Another concern had been Britain’s vote to leave the European Union, which advocates of the Paris deal feared would complicate the bloc’s ratification process and raise questions about Britain’s own climate policy. But Theresa May, the new British prime minister, pledged before the General Assembly on Tuesday that her government too would legally join the Paris agreement this year. 
 
 “The Parliament of Europe,” said Ségolène Royal, the French environment minister who presided over the Paris climate summit meeting and has taken a leading role in pushing for ratification of the deal this year, “will be able to do it even without agreement of all 28 countries.” 
 
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 At the ceremony on Wednesday, it is expected that at least 20 other countries — including Albania, Argentina, Bolivia, Brazil, Canada, Costa Rica, Indonesia, Iran, Mexico, New Zealand and Saudi Arabia, which together represent about 8 percent of total world emissions — will submit their legal paperwork or pledge to do so by the end of the year, United Nations officials said. 
 
 The governments of Chad, Egypt, Ethiopia, Ghana, Honduras, Kuwait, Madagascar, Mali, Niger, Rwanda and Ukraine, which together represent roughly 2 percent of global emissions, are expected to pledge to submit their legal documentation of commitment to the Paris accord by the end of the year. 
 
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 “The Paris agreement gives a framework to act, but there must be a sense of urgency about bringing the agreement into force,” President Obama said on Tuesday in his last address as head of state to the General Assembly. 
 
 The accord approached its legally binding threshold this month after the United States and China, which together account for nearly 40 percent of emissions, jointly announced that they would legally join the deal. About two dozen other countries, collectively representing about 2 percent to 3 percent of global emissions, have also legally joined it. 
 
 But many of the largest polluters have not signed on. In an interview, Ms. Royal conceded that the European Union’s power move would inflame opposition from some member countries. “Three or four countries will be very difficult,” she said. “But it will pass.” 
 
 Still an open question are the timetables of the world’s three other major polluters: India, which accounts for about 7 percent of emissions, Russia, which produces about 5 percent, and Japan, which produces about 3 percent. 
 
 Prime Minister Narendra Modi of India has worked closely with Mr. Obama and Mr. Ban on the issue of climate change, but members of his Parliament remain wary of a deal that would require emissions cuts as the country seeks to supply cheap electricity to millions of impoverished people. 
 
 Japanese officials say there is a good chance that Tokyo will pass the deal in the autumn session of the Diet. 
 
 Russian officials did not respond to emailed questions about their plans, but United Nations officials said they were optimistic that Moscow might sign on by year’s end. President Vladimir V. Putin, who has mocked the science of climate change, surprised many when he showed up at the Paris accord negotiations and promised to prioritize the deal. 
 
 “Putin is having a conversation with the Russian government,” said Robert Orr, the dean of the University of Maryland School of Public Policy and a special adviser to Mr. Ban. “It’s one of the governments that has surprised many with how forward-leaning they are on this. That’s the kind of situation we would like to see.” 
 
 Mr. Orr and others noted that Russia’s commitment under the Paris deal would not be difficult to meet — it is one of the weakest pledges and is unlikely to do much to significantly reduce pollution. But they said Mr. Putin’s legal acceptance of the deal would still be valuable. ||||| 3 Ways Trump Could Abandon the Paris Climate Pact 
 
 The possibility that a climate science denier could soon become America’s president is serving as an urgent motivator for diplomats gathering in New York this week for United Nations meetings. 
 
 Donald Trump, the Republican presidential nominee, has called climate change a “hoax” and said that as president he would “cancel” the UN’s new climate pact, the Paris agreement, which was finalized last December. 
 
 If enough countries join the U.S., China and Brazil in formally committing to join the pact this year, it’s been reported that the pact would become “Trump-proof.” Legal experts, however, say a Trump administration would have several options for abandoning the agreement during its first term, which would severely jeopardize its potential to succeed. 
 
 Presidential candidate Donald Trump. 
 
 Credit: Matt A.J./flickr 
 
 Global unity to tackle climate change was found between nearly 200 countries in December during the crucial treaty negotiations in Paris, influenced by the leaders of the U.S. and China, which are the world’s biggest greenhouse gas polluters. 
 
 Under the Paris agreement, countries volunteer to take steps to reduce their impacts on the climate beginning in 2020. The U.S. has pledged to reduce its pollution levels in 2025 to 26 percent below its 2005 levels, largely by switching away from burning coal for electricity. 
 
 Future talks are designed to see national pledges improved, with the goal of keeping warming to well below 2°C (3.6°F) above pre-industrial times. The earth’s surface has already warmed a little more than half that amount since then, and concentrations of heat-trapping greenhouse pollution are rising at a steady rate. Every month since the deal was struck has broken a global temperature record. Rising temperatures are worsening floods, fires, heat waves and other disasters. 
 
 The vulnerability of the climate pact shows efforts to curb warming’s impacts remain beholden to the whims of elections and personalities. More than a year of campaigning has shown there are few personalities in politics larger and less predictable than Trump’s. As president, Trump couldn’t “cancel” the Paris agreement, but he would have at least three options for walking America away from it. 
 
 If elected president, legal precedent and a careful reading of Article 28 in the Paris agreement indicate he would have the power to formally withdraw the U.S. from it as soon as a year after it takes effect by abandoning a 1992 treaty — without any need for lawmaker approval. 
 
 A second option, which would be slower but somewhat less confrontational, could see Trump wait until the end of his first term before taking advantage of a provision in the agreement that would let him yank America from the pact. 
 
 The third option may be the easiest of all. Even without withdrawing formally, a Trump administration could undermine the agreement by abandoning rules, incentives and programs designed to reduce pollution, preventing the U.S. from living up to its new commitments to the climate. Trump has said he would eliminate the EPA, which oversees many of those rules and programs. 
 
 While the Paris pact fails to require the types of aggressive actions needed to safely slow global warming, it is nonetheless considered a landmark political achievement. 
 
 If the “U.S. or any large country walks away from the agreement,” said Harjeet Singh, an ActionAid official based in India, where he works on international climate issues, it would represent an “epic failure” to not build on what had been a “huge political feat.” 
 
 If the Paris agreement takes effect before the presidential inauguration in January, here’s a look at the three most likely options a Trump administration may pursue for stepping away from it: 
 
 The Passive Option 
 
 If the U.S. withdrew from the Paris agreement, the diplomatic blowback could dwarf the global imbroglio that followed President George W. Bush’s 2001 announcement that he wouldn’t implement the Kyoto protocol, which was ultimately a failure. 
 
 “The pushback would be greater,” said Dale Jamieson, a New York University environmental studies and philosophy professor who has tracked global climate diplomacy for years. “Since Paris doesn't commit people to much of anything anyway, it would be stupid beyond belief for him to withdraw — and there wouldn't be much reason for people to try to save it.” 
 
 Instead of withdrawing formally, Trump as president could simply disassemble environmental regulations and undermine national efforts to reduce greenhouse gas pollution. Harvard professor Robert Stavins said that and other measures could “all but ensure” that America would fail to live up to its commitments under the Paris agreement. 
 
 The Slow Option 
 
 There’s a more deliberate path that Trump could take to extract America from the pact, but it would require waiting until the end of what would be his first term. 
 
 The agreement says countries must wait at least three years after formally joining the agreement before they can file paperwork needed to withdraw from it, followed by an additional one-year wait. 
 
 Obama filed paperwork with the UN this month indicating the U.S. is ready to join the Paris agreement. Once at least 55 countries, responsible for at least 55 percent of greenhouse gas pollution, have filed similar paperwork the Paris agreement will take effect and those 55 or more countries will join. 
 
 It currently seems likely that the agreement will take effect before the January inauguration of America’s 45th president. By Monday morning 28 countries had submitted their paperwork, and more filings are expected this week as the UN holds annual meetings in New York. 
 
 A view of Manhattan over the top of the Headquarters of the United Nations. 
 
 Credit: Anthony Quintano/flickr 
 
 The Aggressive Option 
 
 By invoking a little-noticed provision of the Paris agreement, legal experts point out the four-year waiting period could be cut to one year by withdrawing the U.S. from a 1992 climate treaty. 
 
 When Obama formally signed onto the Paris agreement this month, he didn’t need Senate approval to do so. That’s because it’s consistent with existing laws and agreements — most notably the 1992 UN Framework Convention on Climate Change (UNFCCC), an international treaty. 
 
 The Paris agreement states that any country that withdraws from the 1992 treaty “shall be considered as also having withdrawn” from the agreement. 
 
 “The U.S. could withdraw from the UNFCCC with one year’s notice, which would also effectuate a withdrawal from the [Paris agreement],” Arizona State University law professor Dan Bodansky said. 
 
 Although the 1992 treaty was ratified by the Senate, history suggests a president would not need the Senate’s blessing before withdrawing from it. 
 
 “The president has plenary authority to manage foreign affairs,” said Michael Wara, an environmental law expert at Stanford. “Since the Constitution is silent as to treaty withdrawal, a president can do that without consulting with Congress.” 
 
 Wara pointed out that in 1992, President George W. Bush withdrew the U.S. from an anti-ballistic missile treaty that the Senate had ratified in 1972 without seeking the Senate’s approval. After President Carter withdrew from a defense treaty with Taiwan, the Supreme Court refused to hear a challenge filed by members of Congress. 
 
 “The UNFCCC is a forum for negotiating, and withdrawal from that would essentially be saying, ‘We’re not even going to talk about this any more,” Wara said. 
 
 If the U.S. withdrew from or undermined the Paris agreement, reprisals from other countries may be sharp — but they would probably be indirect. 
 
 “What are the other countries going to do to retaliate? Emit more greenhouse gas emissions? Of course not,” Wara said. “But it would mean that when we need their help to achieve some other diplomatic objective, they would trust our promises much less.” ||||| Transcripts show the Democratic presidential nominee referred to climate change directly in less than half as many speeches after her left-wing rival conceded defeat, reports Climate Home 
 
 Hillary Clinton has dropped the words “climate change” from most of her public addresses since winning the endorsement of her party rival Bernie Sanders, according to Climate Home analysis. 
 
 While the presidential candidate talks regularly about her plan for the US to become a “clean energy superpower”, in recent months she has rarely made reference to the planetary crisis that necessitates it. 
 
 On Monday, when she launched her pitch to millennials online, she could find no room for an issue that will affect that voting cohort more than any other. 
 
 The rhetorical shift undermines hopes that climate change might emerge as a key campaign issue in 2016. Boosted by the disparity between Clinton and her Republican opponent Donald Trump, a self-professed non-believer in climate change. 
 
 Indeed, the signs were there. During the last six months of Clinton’s primary campaign against Sanders, the transcript log of her speeches shows she was talking about climate change at one out of every two speeches she gave. 
 
 But since Sanders endorsed Clinton on July 12, the full focus of the Clinton campaign has swung to Trump. In 38 speeches since that date, Clinton mentioned climate change specifically eight times. Just once every five public addresses. 
 
 “As Bernie reminds us so powerfully, we owe it to future generations to work together to combat climate change,” said Clinton as she accepted Sanders’ endorsement. 
 
 Bernie Sanders (@SenSanders) Without action on climate change, the average 21-year-old college graduate in the class of 2015 will lose over $126,000 in lifetime income. 
 
 The overwhelming priority for progressive Americans is to avoid a Trump presidency. This has necessitated a change in tone, said Prof Robert Stavins, director of the Harvard Environmental Economics Program. “The Clinton campaign needs to target its messages to independent, undecided voters at this point. Speaking to her own constituency on the left would not be a productive use of her time and effort.” 
 
 Research from Yale released in July indicates that even during the hottest year ever recorded, only the 17% of voters who describe themselves as “alarmed” about climate change rank it as a top tier election issue. Meanwhile, Trump has framed Clinton’s climate change response as a “poverty-expansion agenda”. The economy ranks in the top two defining policy areas for all other voters. 
 
 The Democratic primary season was altogether different. Clinton, the overwhelming favourite for the nomination, was ambushed on the left by her socialist rival. To tackle climate change, Sanders had promised to declare legislative war on fossil fuel companies. For her part, Clinton announced a plan to increase US solar capacity seven-fold by 2020. In the spring, she rolled out a wider platform on environmental justice and protection. 
 
 After a sometimes antagonistic campaign, Sanders and Clinton appeared together in New Hampshire and Sanders offered her his endorsement. Speaking to a crowd that contained some vocal and disaffected Sanders supporters, Clinton accepted her opponent had done much to frame climate change as a battle for justice. 
 
 “As Bernie reminds us so powerfully, we owe it to future generations to work together to combat climate change,” she said. 
 
 In the days before the endorsement, Sanders’ team had worked to extract every concession possible from Clinton in the text for the Democratic Party platform. The resulting draft was “the most aggressive plan to combat climate change in the history of the Democratic Party”,according to his policy director Warren Gunnels. “But we are not finished. We have got to follow through on the promise of this agreement.” 
 
 The most notable insertion was a call for a price on carbon, which Clinton has never publicly backed. “It’s not her plan,” her energy policy advisor Trevor Houser told AP. 
 
 David Axelrod, a former senior political adviser to president Barack Obama, told the New York Times he would advise Clinton to avoid playing into Trump’s hands on the issue of carbon pricing. “If I’m in her campaign, I don’t want to hand a cudgel to the other side,” he said. 
 
 Hillary Clinton (@HillaryClinton) Making the wrong choice on climate change would be a disaster for our kids and grandkids. pic.twitter.com/dhc0OABqml 
 
 Climate coyness was a feature of Obama’s first term (when Axelrod was at the White House). According to analysis of speeches from 2008 to 2011, climate change was hardly mentioned even as Obama began to ramp up funding for climate-related projects. 
 
 “He was doing more than he was talking about because he was going incognito to avoid attacks from the Republicans,” said Timmons Roberts, Ittleson professor of environmental studies at Brown University, who conducted the analysis. 
 
 Obama has since emerged as something of a climate warrior, but even in the election campaign for his second term he barely spoke about climate change, said Roberts. “I think he’s careful to not whack the hornets nest of the ideological and fossil fuel interests on the right.” 
 
 John Podesta was the silent architect of Obama’s climate policy. He is now Clinton’s campaign chair. 
 
 A spokesman for the Clinton campaign told Climate Home: “Hillary Clinton believes climate change is an urgent threat and a defining challenge of our time. That’s why she’s been discussing her bold and ambitious plan to transform US energy and combat the harms of climate change throughout this campaign.” 
 
 “The most important data point is that Hillary Clinton is running on the strongest clean energy and climate platform of any candidate in history and Donald Trump is running on the absolute worst,” said Sierra Club executive director Michael Brune. “We’re always eager to see this difference talked about more… because more conversation makes it more clear just how obvious the choice for climate voters is this election.” 
 
 
 
 Nevertheless, Clinton’s realpolitik has left some Sanders supporters worried about how she will represent their issues as president. 
 
 Roberts, an avowed feeler-of-the-Bern, said: “It’s not a core issue for her, it’s an add-on. I think her positions have really been lacking an understanding of the depth and breadth of the transformation that’s necessary. Her position has always been that we can build 500 million solar panels, but she never really addresses actively shutting down the fossil fuel side.” 
 
 On carbon pricing and fracking he believed Clinton had failed to take the stance necessitated by the climate crisis. 
 
 “In fact there is a big haemorrhage of her supporters over to Jill Stein of the Green Party and she’s got to win those people back,” he said. 
 
 Climate Home searched for the words “climate change” in all speech transcripts published on the Clinton campaign website between the beginning of 2016 and early-September. Results can be accessed here. 
 
 
 
 The majority of recent mentions were jabs at Trump’s climate scepticism. On 30 July in Johnstown, Pennsylvania she lampooned him for applying for help to protect a golf course from climate change whilst “he dismisses it as a Chinese hoax”. 
 
 Throughout the year there is a clear regional trend, with Clinton restricting herself to mentioning climate change only in the north east, California and on one trip to Florida. 
 
 A search for the word “environment” reveals just how little weight Clinton’s campaign considers broader environmental issues to have with voters. In the 78 speeches for which Clinton’s campaign have logged transcripts in 2016, she mentions the word in just four. 
 
 “Hillary Clinton’s silence on the issue of the depth of the ecological crisis is deafening,” Greens presidential candidate Jill Stein, who had a warrant issued for her arrest after participating in a protest against the Dakota Access pipeline, told Climate Home. “While she makes the occasional passing nod to the environment, I have made it the very cornerstone of my entire campaign.” 
 
 Note: The article was amended to clarify it was Clinton’s online pitch to millennials that does not mention climate change, not her speech on Monday, which did. ||||| WASHINGTON (Reuters) - Hundreds of top scientists warned on Tuesday against Republican presidential nominee Donald Trump’s vow to pull the United States out of the Paris climate-warming accord if elected in November. 
 
 Republican presidential nominee Donald Trump holds a campaign rally in Fort Myers, Florida, U.S. September 19, 2016. REUTERS/Jonathan Ernst 
 
 The 375 members of the U.S. National Academy of Sciences, including 30 Nobel Prize winners, said in an open letter that a U.S. abandonment of the agreement would make it far harder to develop global strategies to lessen the impact of global warming. 
 
 “Thus it is of great concern that the Republican nominee for President has advocated U.S. withdrawal from the Paris Accord,” the letter said. 
 
 “A ‘Parexit’ would send a clear signal to the rest of the world: ‘The United States does not care about the global problem of human-caused climate change. You are on your own.’” 
 
 Among the signers are biologist E.O. Wilson, physicists Stephen Hawking and Claude Canizares, astrophysicist Simon D.M. White, and Nobel winners Thomas Steitz, Michael Levitt and William Daniel Phillips. 
 
 The National Academy of Sciences is a private society of scholars who advise the United States on science and technological matters. The signers of the letter said they did so as individuals and not on behalf of the Academy or their institutions. 
 
 In Paris last December, almost 200 countries agreed to slash greenhouse gases and keep global temperature rises to “well below” 2 degrees Celsius. The United States and China, the two largest producers of carbon emissions, ratified the accord this month. 
 
 Trump will speak at a natural gas industry conference in Pennsylvania on Thursday. A Trump spokeswoman did not respond to a request for comment. 
 
 Trump has dismissed manmade climate change as a hoax invented by the Chinese and says he will abandon the Paris agreement if elected. 
 
 He has vowed to reverse much of the work the administration of President Barack Obama has done to address climate change, including rules to curb greenhouse gas emissions. 
 
 The Republican Party platform also questions the legality of Obama’s executive order ratifying the Paris deal. 
 
 Democratic presidential nominee Hillary Clinton is a strong supporter of the Paris accord. ||||| Secretary-General Ban Ki-moon speaks during the 71st session of the United Nations General Assembly, Tuesday, Sept. 20, 2016, at U.N. headquarters. (AP Photo/Julie Jacobson) (Associated Press) 
 
 Secretary-General Ban Ki-moon speaks during the 71st session of the United Nations General Assembly, Tuesday, Sept. 20, 2016, at U.N. headquarters. (AP Photo/Julie Jacobson) (Associated Press) 
 
 STOCKHOLM (AP) — Thirty more countries are expected to formally join the Paris Agreement on climate change this week, greatly improving the pact's chances of coming into force just a year after it was negotiated in the French capital, the United Nations said Tuesday. 
 
 More than 170 world leaders have signed the deal, but it won't take effect until 55 countries accounting for at least 55 percent of global emissions have ratified or accepted it through their domestic procedures. 
 
 That was initially expected to take several years, but 28 countries accounting for 39 percent of emissions including the world's two biggest emitters, the United States and China, have already ratified the deal. 
 
 The 30 ratifications expected to be handed to U.N. Secretary-General Ban Ki-moon at a special event at U.N. headquarters in New York on Wednesday would bring the total to 58 countries — but many are small and their total emissions likely won't reach the required 55 percent. 
 
 Brazil, Mexico and Argentina are the largest emitters on the list announced late Tuesday by the United Nations. But the 30 countries will only bring the emissions total to 47 percent. 
 
 At least half a dozen small island nations including Papua New Guinea, Tonga and Kiribati are expected to ratify along with several countries from Central America, Africa, Asia and one from the Mideast — the United Arab Emirates. 
 
 "We are ready. We will announce it in New York," Moroccan Environment Minister Hakima el-Haite told The Associated Press. 
 
 In the world of international diplomacy, this is considered a blistering pace, reflecting a sense of urgency in the fight against global warming and a desire to seal the deal before Ban and U.S. President Barack Obama leave office. 
 
 After years of negotiations, governments agreed in Paris last December to curb the emissions of carbon dioxide and other greenhouse gases that scientists say are warming the planet. 
 
 Ban, who has made climate change a top priority since he became secretary-general nearly 10 years ago, urged world leaders in his keynote speech at the U.N. General Assembly on Tuesday to bring the Paris Agreement into force by the end of the year. 
 
 "The Earth assails us with rising seas, record heat and extreme storms," Ban said. "With the Paris Agreement on climate change, we are tackling the defining challenge of our time." 
 
 U.S. diplomats are also pushing other countries to accelerate their ratification efforts so that the deal can enter into force this year. The White House says Obama and Secretary of State John Kerry plan to corner foreign leaders in the hallways during the U.N. gathering to personally pressure them to join this week. 
 
 "We're very anxious to have it move forward quickly," U.S. climate envoy Jonathan Pershing told the AP. "We are talking to everybody about the urgency." 
 
 Pershing said the haste comes down to the fact that "this is a problem that can't wait." 
 
 Others say another factor is the potential of a shift in U.S. climate policy depending on the outcome of the presidential election in November. Democratic Party candidate Hillary Clinton has said the U.S. must implement the Paris Agreement, but Republican candidate Donald Trump has said he will cancel the deal. 
 
 "The Obama administration clearly would like to see this done before they leave office," said Alden Meyer, a veteran observer of the U.N. climate talks at the Union of Concerned Scientists. 
 
 "That doesn't guarantee that the next president will fully implement Paris," Meyer said. "But it would take at least four years for the U.S. to formally withdraw." 
 
 The Paris Agreement asks both rich and poor countries to take action to curb the rise in global temperatures that is melting glaciers, raising sea levels and shifting rainfall patterns across the globe. It requires governments to present national plans to reduce emissions, though the targets themselves aren't internationally binding. 
 
 The European Union, which considers itself as one of the architects of the Paris deal, is trying to fast-track its ratification process to avoid the embarrassment of sitting on the sidelines when it comes into force. 
 
 The EU, which accounts for 12 percent of global emissions, originally planned to wait for its 28 member states to approve the deal domestically, but now wants to ratify it on their behalf. 
 
 "It's technically possible," said Anna-Kaisa Itkonen, a spokeswoman for EU Climate Commissioner Miguel Arias Canete. "But politically it's a decision of the member states." 
 
 With or without the EU, there's a chance that the deal can enter into force as early as the next U.N. climate conference, which starts Nov. 7 in Marrakech, Morocco. 
 
 For some the timing is mostly symbolic, because the first round of emissions targets doesn't start until 2020. For others, like the island nations who face an existential risk from rising seas, it's imperative that countries prepare to implement — and improve — their targets as soon as possible. 
 
 "We cannot wait," said Maldives Environment Minister Thoriq Ibrahim, who chairs an alliance of small island states. "We are at the forefront of climate change and we are the people who will suffer if there is no action taken early." 
 
 ___ 
 
 AP writers Edith M. Lederer, Michael Astor and Josh Lederman at the United Nations contributed to this report. 
 
 ___ 
 
 Follow Karl Ritter on Twitter at https://twitter.com/Karl_Ritter
– Donald Trump has described climate change as a hoax and a fraud—but he has inadvertently done more than most to bring about worldwide agreement on the issue. The New York Times reports that fear of a Trump presidency has helped United Nations Secretary-General Ban Ki-moon persuade more countries to ratify the Paris climate pact, which is now expected to enter legal force by the end of this year. Trump has vowed to pull the US out of the pact—but President Obama has already ratified the deal, and the withdrawal process takes four years. A round-up of coverage: The AP reports that 30 more countries are expected to join the Paris deal this week, bringing it much closer to the target of 55 countries representing at least 55% of emissions. When that target is hit, the deal will officially come into force. Some 375 scientists from the National Academy of Sciences and foreign affiliates—including Stephen Hawking and almost 30 other Nobel Prize winners—signed an open letter Tuesday criticizing Trump's pledge to pull the US out of the deal, reports Reuters. The move "would send a clear signal to the rest of the world: 'The United States does not care about the global problem of human-caused climate change,'" they wrote. Climate Central reports that the deal won't be completely "Trump-proof" even if it comes into effect soon. Even if withdrawal takes years, he will be able to undermine it by abandoning plans to reduce pollution. Trump has already said he plans to get rid of the EPA. The Guardian reports that climate change hasn't been as big an election issue as some had expected: Since winning the endorsement of Bernie Sanders, Hillary Clinton is mentioning the issue a lot less, with roughly one mention per five speeches, compared to one in two before the endorsement.