Barack Obama will warn that a one-foot rise in sea levels could cost the United States as much as $200 bn

President Barack Obama will on Wednesday warn that a one-foot rise in sea levels could cost the United States as much as $200 billion, in a speech warning of the security risks of climate change.

In a commencement address to the United States Coast Guard Academy, Obama will warn that climate change presents the most serious risk to national security, a risk that is immediate and acute.

"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," he is expected to say.

"Make no mistake, it will impact how our military defends our country. And so we need to act—and we need to act now."

The White House believes that rising sea levels is chief among these risks.

"Climate change, especially rising seas, is a threat to our homeland security—our economy, infrastructure, and the safety and health of the American people."

"It's estimated that a further increase in of one foot -— just one foot -— by the end of this century could cost our nation $200 billion," Obama will say.

The Pentagon is taking the matter so seriously that according to White house officials, it is assessing the vulnerability of more than 7,000 bases, installations and other facilities to .

The military is also studying the impact of the National Guard being deployed to deal with the aftermath of extreme weather.

The US military is studying the impact of the National Guard being deployed to deal with the potential aftermath of extreme weather

Obama has launched a high-profile push to raise awareness about the dangers facing the environment.

After a landmark bilateral deal last year that committed China to emissions cuts, the administration says it would like to see a binding global deal reached in Paris this December.

Barack Obama has launched a high-profile push to raise awareness about the dangers facing the environment