"Just because the President announces it doesn't mean Congress will pass it," he said.
The funds would go to a new U.N. Green Climate Fund that leverages public and private money to help developing countries adapt to and mitigate the effects of climate change. Christiana Figueres, who leads the U.N. Framework Convention on Climate Change, has called for an initial capitalization of $10 billion; Japan is reported to have promised an additional $1.5 billion, according to reports, and at least 10 other countries have pledged around $3 billion (See the full spending commitments from every country here).
Appropriating funds for international climate work isn't new—in fact, it was Republican President George W. Bush who first pledged $2 billion to a Climate Investment Fund run out of the World Bank. In his 2008 State of the Union address, Bush said the investment would "create a new international clean-technology fund, which will help developing nations like India and China make greater use of clean energy sources," while also calling for an international climate deal.
The U.S. has also paid out between $800 million and $900 million a year in direct climate spending, largely through a Global Climate Change Initiative established in 2010. That funding runs through the State and Treasury Departments and USAID and goes to clean energy, adaptation, a strategic climate fund, and other global developments. (A May 2013 Congressional Research Service report breaks down the spending.) The total includes roughly $300 million for the Climate Investment Fund, which is due to be paid out sometime in fiscal 2016.
Michael Wolosin, an analyst with Climate Advisers, said that direct spending accounts for only about a third of what the U.S. considers its international climate investment—the government also adds up some clean-energy spending through programs such as the Export-Import Bank and the Overseas Private Investment Corporation, plus indirect climate benefits from biodiversity and food-security programs. (This analysis by Wolosin looks at the GCCI in depth.)
Given all of that, Wolosin said it was likely that direct climate spending would still have to go up by roughly a third. "Whether that happens or not is really about political will and how much the Obama administration prioritizes this," he said.
An administration official said that averting the worst effects of climate change reduces the need for "more costly interventions to restore stability and rebuild" and that building resilience "helps safeguard our investments in many areas." The funds are also expected to create a larger market for domestic clean energy companies.
"If in fact the litmus test for U.S. expenditures is whether it serves the U.S. domestic and foreign policy interests, then this pledge hits that criteria for investing," said Lou Leonard, vice president of climate change for the World Wildlife Fund. "You can think of it as an ounce of prevention is worth a pound of cure. We can either invest now and create a more resilient world "¦ or we can wait, do nothing, and then spend much more to respond to problems as they arise."