The study maps out the various ways climate change will impact military personnel — from recruitment through training and deployment — including equipment, facilities, supply chain and ability to engage with allies and partners.

Kidd said the work stemmed from an executive order that was issued earlier this year to develop a climate adaptation plan for the Defense Department.

Researchers at Rand looked at a range of climate hazards, including drought, land degradation, coastal flooding, inland flooding, heat, tropical storms, ocean anomalies and sea ice retreat. They then considered how these conditions might affect the military’s ability to defend the homeland, deter outside aggression and carry out strategic attacks.

The report considered the potential consequences if land used for training troops is no longer safe or accessible, or the effect of extreme heat on military installations, aircraft and runways.

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The findings will allow officials to see how exposure to climate hazards directly impacts military readiness, said Katharina Ley Best, a senior operations researcher at Rand and one of the study authors.

The analysis also shows how multiple climate hazards may compound existing problems, and how challenging it may be for the government to address the consequences, according to Kidd.

“It’s not just one thing — you can’t say, ‘Oh, it’s going to be hot, add more air conditioners,’” he said. “Well, air conditioners might bust the grid because of your energy.”

By showing the different ways that climate vulnerabilities are interconnected, the report “starts to tease apart that complexity of these converging effects,” Kidd said.

He added that the findings will help the Defense Department prioritize efforts to address global warming — and identify instances in which adaptation may not be practical.

“In some cases, sadly, we may not have an adaptive option and we have to change either the mission of the installation, or whether or not we retain that installation at all,” Kidd said.