The Federal Emergency Management Agency is making it tougher for governors to deny man-made climate change. Starting next year, the agency will approve disaster preparedness funds only for states whose governors approve hazard mitigation plans that address climate change.

This may put several Republican governors who maintain the earth isn't warming due to human activities, or prefer to do nothing about it, into a political bind. Their position may block their states' access to hundreds of millions of dollars in FEMA funds. Over the past five years, the agency has awarded an average $1 billion a year in grants to states and territories for taking steps to mitigate the effects of disasters.

"If a state has a climate denier governor that doesn't want to accept a plan, that would risk mitigation work not getting done because of politics," said Becky Hammer, an attorney with the Natural Resources Defense Council's water program. "The governor would be increasing the risk to citizens in that state" because of his climate beliefs.

The policy doesn't affect federal money for relief after a hurricane, flood or other disaster. Specifically, beginning in March 2016, states seeking preparedness money will have to assess how climate change threatens their communities. Governors will have to sign off on hazard mitigation plans. While some states, including New York, have already started incorporating climate risks in their plans, most haven't because FEMA's old 2008 guidelines didn't require it.

"This could potentially become a major conflict for several Republican governors," said Barry Rabe, an expert on the politics of climate change at the University of Michigan. "We aren't just talking about coastal states." Climate change affects droughts, rainfall and tornado activity. Fracking is being linked to more earthquakes, he said. "This could affect state leaders across the country."

Among those who could face a difficult decision are Republican Governors Rick Scott of Florida, Bobby Jindal of Louisiana, Chris Christie of New Jersey, Greg Abbott of Texas and Pat McCrory of North Carolina—all of whom have denied man-made climate change or refused to take action. The states they lead face immediate threats from climate change.

The five governors' offices did not return requests for comment by press time.

Environmentalists have been pressing FEMA to include global warming in its hazard mitigation guidelines for almost three years. FEMA told the Natural Resources Defense Council in early 2014 that it would revise the guidelines. It issued draft rules last October and officially released the new procedures last week as partisan politics around climate change have been intensifying.

On March 8, the Florida Center for Investigative Reporting said Scott instituted an unwritten ban on the use of "climate change" or "global warming" by Florida officials. Earlier this month, Republican Sen. Jim Inhofe of Oklahoma took a snowball to the U.S. Senate floor as evidence the climate isn't warming, highlighting GOP leaders' climate views.

"The challenges posed by climate change, such as more intense storms, frequent heavy precipitation, heat waves, drought, extreme flooding, and higher sea levels, could significantly alter the types and magnitudes of hazards impacting states in the future," FEMA wrote in its new procedures.

FEMA's disaster preparedness program has been granting money to states since the 1980s for projects as diverse as raising buildings out of floodplains and building safe rooms. States are required to update their plans every five years to be eligible for the agency's mitigation funding. Since 2010, FEMA has doled out more than $4.6 billion to states and territories as part of this program.

Republican-led regions constitute eight of the top 10 recipients of this category of FEMA money between 2010 and 2014. Louisiana was No. 1, having received almost $1.1 billion from FEMA for hazard mitigation. New Jersey was third with nearly $379 million, and Texas fourth with almost $343 million.

The gubernatorial approval clause was included in the new guidelines to "raise awareness and support for implementing the actions in the mitigation strategy and increasing statewide resilience to natural hazards," said FEMA spokeswoman Susan Hendrick.

The new federal rules don't require public involvement in the creation of states' disaster preparedness plans, eliminating the opportunity for environmental groups and concerned citizens to submit comments or concerns about the assessments.