JOSH LEDERMAN
Associated Press

WASHINGTON (AP) — Having spent political capital fighting climate change at home, President Barack Obama will turn his sights overseas next week, urging fellow heads of state to be as ambitious as possible as they negotiate a make-or-break global treaty to be finalized in Paris next year.

Obama will attend a United Nations climate summit where he will announce new U.S. commitments, aiming to ramp up the pressure on other major polluters like India and China to demonstrate they’re not laggards in the global campaign against climate change.

White House officials said the U.S. will offer tangible contributions such as American technology to help vulnerable populations deal with food security, sea level rise and other negative effects of climate change.

“Our hope is that others will do the same and that can build momentum toward an agreement in Paris,” Dan Utech, Obama’s top adviser on climate and energy issues, said in an interview.

Obama had hoped to focus in his second term on legacy-making projects like curbing climate change. But a dizzying array of global crises has competed for his attention, overshadowing many goals he had hoped to achieve. Over just a few days at the U.N., leaders will be wrangling with deep problems in Ukraine, Iraq, Syria, Iran and Israel, to name a few.

By taking time out at the U.N. for climate change, Obama is working to keep the issue at the top of the global agenda even after the crises of the day recede from memory. More than 100 heads of state will join Obama at the summit, which U.N. Secretary-General Ban Ki-moon is hosting.

The last time Obama gathered with so many leaders to discuss climate change was five years ago in Copenhagen, where a U.N. summit intended to yield a strong accord on emissions ended in failure. That outcome dampened hopes that developed and developing nations could come together to address climate change in any serious way before temperatures spiral out of control.

Obama can’t afford another failure in 2015. The talks already underway under the U.N. umbrella mark the last major opportunity for Obama to leave his imprint on the global response to climate change before his term ends and another president takes over — potentially a Republican who would be less inclined to press the issue.

“If we don’t get a deal next year, I think we’re in for big trouble,” said Rep. Henry Waxman, D-Calif., a prominent advocate for fighting global warming.

Officially, Tuesday’s one-day summit isn’t part of the negotiations for the 2015 agreement, set to take effect in 2020 and apply to all countries. In the coming months, the U.S. and other nations are expected to unveil their emission-reduction targets, and there’s serious concern that countries won’t offer nearly enough to avert the worst effects of climate change. It’s not known what the U.S. offer will be.

There’s also concern that Obama, his poll numbers sagging, lacks the political clout to get the Senate to ratify any such treaty — an obstacle that will become even greater if Republicans seize control of the chamber in November’s elections.

White House officials say it’s possible negotiators could draft an agreement that doesn’t require Senate ratification, but Senate Minority Leader Mitch McConnell, R-Ky., has warned that sidestepping Congress “would be just another of many examples of the Obama administration’s tendency to abide by laws that it likes and to disregard laws it doesn’t.”

By convening heads of state now in front of cameras at the U.N., rather than leaving it to lower-level negotiators until the very end, Obama and U.N. organizers hope to increase the political pressure on leaders to set ambitious targets — especially reticent nations like Australia and major polluters like China and India.

The summit’s major take-away will be specific actions that world leaders are expected to announce, as confidence-building measures toward an accord in Paris. John Podesta, Obama’s senior counselor, said the U.S. will offer to let other nations use scientific data and technical tools that agencies like NASA and the National Oceanic and Atmospheric Administration have developed to boost local resilience to climate change.

Early in his presidency, Obama set a goal to reduce U.S. carbon dioxide emissions by 17 percent by 2020, compared to 2005 levels. With U.S. lawmakers opposed to major climate legislation, Obama has sought to bypass Congress as much as possible. Republicans and even some Democrats have balked at unprecedented pollution limits Obama has proposed for power plants. But the White House said those and other actions have kept the U.S. on track to meet Obama’s 17 percent goal, giving Obama more leverage when he presses other leaders to go just as bold.

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