The US Department of Defence has laid out its plan to respond to climate change, arguing that rising temperatures and more frequent destructive weather around the globe pose “immediate risks to US national security”.

Defence Secretary Chuck Hagel unveiled the Climate Change Adaptation Roadmap at the Conference of Defence Ministers of the Americas held in Arequipa, Peru.

“Climate change is a long-term trend, but with wise planning and risk mitigation now, we can reduce adverse impacts down range,” Hagel said.

The plan calls for the department to identify and assess effects of climate change on the military, integrate climate considerations and collaborate with other federal agencies and state governments on meeting challenges. President Barack Obama has made combating climate change a priority of his second term.

Climate change is a long-term trend, but with wise planning and risk mitigation now, we can reduce adverse impacts down range

With climate legislation stalled in Congress, Obama has pledged to use the executive branch to help with reining in greenhouse gas emissions.

Republicans have criticised the Obama administration’s focus on climate.

They say it has come at the expense of the economy and that taxpayer dollars might be better spent.

While it may not be possible to precisely project all of the impacts of climate change, Hagel said that uncertainty “cannot be an excuse for delaying action”.

Rising sea levels, extreme weather events and other consequences of a changing climate could exacerbate “many challenges, including infectious disease and terrorism”, the department said.

“The military could be called upon more often to support civil authorities, and provide humanitarian assistance and disaster relief in the face of more frequent and more intense natural disasters,” the plan noted.

Hagel warned that the department was already beginning to see some of these impacts.

Climate change can also affect the military at home, they said.

The plan warned that areas like the Hampton Roads region in south-eastern Virginia, which houses the largest concentration of US military sites in the world, sees recurrent flooding now and could experience a rise of 0.45m in sea levels in the next 20 to 50 years.