By creating the Snow, Ice and Permafrost Research Establishment (SIPRE) in 1949, the U.S. military became one of the earliest climate research groups on the planet.

The group’s mission was to study the science and engineering of the warming Arctic and the national security implications that could follow. University of Vermont professor and geoscientist Paul Bierman wrote about this in his book, “When the Ice Is Gone: What a Greenland Ice Core Reveals About Earth’s Tumultuous History and Perilous Future.”

He spoke to MPR chief meteorologist Paul Huttner for Climate Cast.

The transcript below has been lightly edited for clarity and length.

How and when did the U.S. military become interested with climate changes in the Arctic?

They actually got interested during World War II, when they occupied parts of Greenland in part to rescue bomber and fighter pilots who'd landed on the ice and realized how ill-equipped they were to operate in frozen environments. They really stepped it up, though, in the early to mid-50s, fighting the Cold War in the Arctic.

From the military’s point of view, climate change is important in variety of ways. It’s certainly important in the Arctic, where the very stability of the ground they’re working on is questionable, but it’s also very important in the sense that when you melt ice sheets, you raise sea level.

That has huge implications for human migration around the world, and for things as simple as five of the U.S. aircraft carriers that are berthed in Virginia — which is a sea-level-rise hot spot and will find their docking facilities under water in the next couple decades.

What does the military mean by the phrase ‘climate resilience is force resilience’?

They mean that in the sense of trying to reduce the risks to active military, reduce the number of global conflicts that will come from climate change, and be prepared for the eventualities of bigger storms, higher temperatures — all those sorts of things that affect maneuverability on the ground to the safety of soldiers.

So in one way, moving toward renewable energy takes them away from dependence on fossil fuels and the need to transport those fossil fuels.

Another idea that jumped out at me in your book is that for the military, climate change is ‘too costly to ignore.’

There are estimates that suggest if we let sea level rise uncontrollably, which would be from the melting of the Greenland and Antarctic ice sheets, it could cost the global economy trillions of dollars in losses because of the flooding that’s going to occur around every coastline.

So the military is also looking, of course, at the prices of fossil fuels. We're at a point now where solar and wind are competitive, if not cheaper, than typical fossil fuel energy sources.

The U.S. Army drilled the first deep ice core in Greenland. How old was it, and what did they find?

The military drilled the ice core through almost a mile of ice, and then they drilled through about 12 feet of frozen soil. The ice itself goes back about 100,000 years, but the frozen soil takes us back millions.

What’s most important about what they found in that frozen soil is that the upper portion of it — dated to about 400,000 years ago — is full of plant fossils and fossils of insects. Those are important because they are very strong evidence that the ice sheet there had to vanish, and when it vanished, a mile of ice disappeared.

If we don’t control climate change and global warming, at this point, we’re going to repeat the past, and a mile of ice is going to melt again.

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