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The US military is quietly going green

A Navy carrier strike group conducts operations in the Arabian Sea on May 17, 2019.
  • Justin Rohrlich
By Justin Rohrlich

Geopolitics reporter

Published This article is more than 2 years old.

US defense leaders recognize the threat of climate change, even if their commander-in-chief doesn’t.

American military strategists have long viewed climate change as a “threat multiplier.” The Pentagon, in its 2014 Quadrennial Defense Review, said the changing weather will “aggravate stressors abroad such as poverty, environmental degradation, political instability, and social tensions.”

The 2018 congressional Defense Authorization Act said climate change is “a direct threat to the national security of the United States and is impacting stability in areas of the world both where the United States Armed Forces are operating today and where strategic implications for future conflict exist.”

The US intelligence community’s most recent Worldwide Threat Assessment, released in January, identified climate change as “likely to fuel competition for resources, economic distress, and social discontent through 2019 and beyond.”

This all stands in stark contrast to the position of US president Donald Trump and his administration, which has called climate change a hoax. But from a defense perspective, ignoring the implications of environmental change “is the antithesis of proper military planning,” says Ray Mabus, the US secretary of the Navy from 2009 to 2017.

So the Department of Defense marches on, quietly.

“The military continues to make the preparations that it needs to for a hotter world,” Mabus told Quartz. “But they have to be very circumspect about it. They can’t call it out. They can’t ask for money specifically for it in the budget. And when you tell the military that for political reasons you shouldn’t do stuff that is science-based, that—just as a general thing—is really bad.”

As part of its overall strategy, the US military is not just writing contingencies for potential conflict sparked by a warming climate, however–it’s also attempting to reduce its own greenhouse gas emissions and to rely less on fossil fuels. From the military’s perspective, the future effectiveness of America’s armed services actually hinges on going green.

The world’s largest polluter

At the UN General Assembly in September, climate action was the central issue on the table. Numerous member countries—save, notably, the US, China, and India (the usual holdouts)—made new pledges to reduce emissions and, crucially, some major corporations for the first time made their own commitments.

Among institutions, however, the US military is the world’s largest consumer of fossil fuels and, as such, is the most prolific emitter of greenhouse gases anywhere.

Neta Crawford, chair of the political science department at Boston University, published a study earlier this year that analyzed the military’s oil consumption. She found that since the start of the Afghanistan War in 2001, the military’s fuel purchases have averaged about 100 to 120 million barrels a year, depending on the number of troops deployed. Between 2010 and 2017, the Defense Department’s burning of fossil fuels accounted for about 44 million metric tons of CO2 emissions annually. That’s more CO2 than the entire country of Denmark emits.

To reduce the military’s emissions, Crawford said, there needs to be a complete top-to-bottom “rethink” of the US military, which she said hasn’t happened since World War II. Although this is perhaps not a particularly popular idea in the current era, Crawford believes that reducing the size and scope of the armed forces is a good place to start.

“This is the story of every great power from the Romans, through the Spanish empire, through the French and the British,” Crawford said. “You expand, people resist, you overspend, you must contract. Frankly, I don’t care if the United States stays on top or is even a great power in 50 years. I care about survival, which is why it’s important that we look at this large defense posture and right-size it to the kind of world that we’re in now. That will lead to opportunities to reduce operations, which will lead to reductions in greenhouse gas emissions, which will make the world slightly less filled with carbon dioxide.”

It’s actually a warfighting measure

In the early 2000s, James Mattis, at the time a three-star Marine Corps general, and who would later become Trump’s secretary of defense, called for the armed services to be “unleashed from the tether of fuel.” His desire to reduce the military’s dependence on fossil fuels, however, came not from a desire to pollute less, but to become a more effective fighting force.

Casualties linked to fuel and water transport accounted for 10% to 12% of all Army casualties at the time, according to the Army Environmental Policy Institute. Enemy attacks on fuel supply trucks in Afghanistan resulted in one Marine killed for every 50 convoys, and one Army soldier killed for every 24 convoys. If the Army reduced its fuel consumption, Army researchers found, it could save lives.

The findings inspired Navy secretary Mabus. In 2009 he launched a full-scale rethink of the Navy’s energy usage that included the development of biofuels and other alternatives. He called it the “Great Green Fleet” initiative.

At the time, Mabus said the Navy would launch a fossil fuel-free carrier strike group—that’s an aircraft carrier, a guided missile cruiser, two guided missile destroyers, one attack submarine, and one supply vessel—entirely comprised of hybrid electric ships running on biofuel. It began operations in 2016.

The reason I did what I did on energy and alternative fuels was as a warfighting measure first

Mabus also equipped Marine Corps companies with portable solar panels so they didn’t have to be resupplied with fuel. There are now Navy SEAL teams that Mabus said are close to net zero in terms of both energy and water, which allows them to stay deployed pretty much indefinitely. Not having diesel generators running also means troops can both better hear the enemy and conceal their own positions.

“The reason I did what I did on energy and alternative fuels was as a warfighting measure first,” Mabus said.

Greening the fleet also made good financial sense. Mabus highlighted two examples: Switching to LED light bulbs aboard a destroyer saved the fleet 25,000 gallons of fuel in a single year. And the USS Makin Island, a 40,000-ton amphibious assault ship, saves fuel by using an electric motor for speeds under 12 knots. “It’s the second-biggest ship the Navy builds,” Mabus said. “The first time we sent it out on a cruise, it brought back half its fuel budget and it stayed at sea 45 days longer than any other ship it went with.”

About 40% of the Navy’s energy at sea now comes from alternatives, 17% of which is nuclear, the rest from biofuels made from beef fat, municipal waste, or vegetable oils, Mabus said.

It was an impressive feat. Yet Mabus was forced to defend himself from criticisms that he was using “military money to create a biofuel industry.” And today, Republican lawmakers are attempting to cancel those Mabus-era contracts for biofuel.

The electric drives of Mabus’ Great Green Fleet have been criticized for engineering shortcomings (they are too taxing for backup generators, for instance), and in the 2019 Navy budget, the program’s funding was pulled.

But retired rear admiral Jonathan White, who was director of the Navy’s climate change task force from 2012 to 2015, said electric drive offers the best, most immediate solution to reducing the sea service’s reliance on traditional sources of energy. Nuclear power has long been utilized safely by the Navy to power aircraft carriers and submarines, and its use should also be expanded, he told Quartz, adding that it may soon become possible to make fuel from seawater. None of that can happen, however, without commitment and funding.

In a way, the Navy is in the best position in the military to see the potential dangers of climate change up close. Rising sea levels could render the Reagan Test Site, a multibillion-dollar missile tracking installation in the South Pacific, unusable in 20 years. A three-foot sea level rise would put at least 128 military bases in the US at risk of becoming submerged, including the Norfolk Naval Base, the largest Navy installation in the world. 

“They’re already having so-called “king tides” [in Norfolk] that we used to see maybe once every couple of years,” Mabus said, referring to the kind of severe high tides that can cause coastal flooding. “Now we’re seeing them several times a month.”

He added that sometimes the waters around Norfolk get so high that they flood the area’s roadways. And if sailors can’t get to the base, the fleet can’t go to sea.

Mabus, who once served as governor of Mississippi and was appointed US ambassador to Saudi Arabia by president Bill Clinton in 1994, pointed to an anecdote he once heard from the Kingdom’s oil minister while stationed in Riyadh. “The Stone Age didn’t end because we ran out of stones,” Mabus recalled the minister saying. “It ended because we invented something better.”

Mabus believes that eventually the world will “leave oil and gas in the ground” in favor of alternative sources of energy. “It’s just [a matter of] how fast it happens,” he said. “That’s the question now, and whether it will be quick enough to stave off some really major disasters.”

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