Obama to sound alarm on climate change

President Obama will stress the importance of combating climate change during a commencement speech Wednesday at the U.S. Coast Guard Academy, according to a White House official.

"This is not just a problem for countries on the coast or for certain regions of the world. Climate change will impact every country on the planet. No nation is immune," the president will say, according to his prepared remarks. "So I am here today to say that climate change constitutes a serious threat to global security, an immediate risk to our national security, and, make no mistake, it will impact how our military defends our country. And so we need to act--and we need to act now."

"You are part of the first generation of officers to begin your service in a world where the effects of climate change are so clearly upon us," Mr. Obama will tell the graduates. "Climate change will shape how every one of our services plan, operate, train, equip, and protect their infrastructure, today and for the long-term."

The president will call climate change a threat to homeland security, highlighting flooding in places like Miami, Florida and Charleston, South Carolina to underscore the vulnerability of much of America's coastal infrastructure. He'll also frame climate change as a threat to the readiness of the U.S. military.

The Obama administration has seen mixed results in its drive to reduce carbon emissions and blunt the impact of climate change. A 2009 "cap and trade" proposal that would have put a price on companies' excess carbon emissions passed the House but died in the Senate. But last June, the president moved unilaterally, directing the EPA to limit the carbon emissions from coal-fired power plants. That measure takes effect this summer.

Republicans have generally opposed the administration on the issue. Some dispute the science behind climate change, questioning whether humans are responsible for global warming. Others say the president's proposed solutions are too costly -- that they'd raise the cost of energy for businesses and consumers without making a sizable dent in global carbon emissions.