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Defense Secretary Calls Climate Change an Existential Threat

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Secretary of Defense Lloyd J. Austin III spoke today at the Leaders Summit on Climate.

"Today, no nation can find lasting security without addressing the climate crisis. We face all kinds of threats in our line of work, but few of them truly deserve to be called existential. The climate crisis does," he said, adding that "climate change is making the world more unsafe and we need to act."


The climate crisis is a profoundly destabilizing force for the world, Austin said. As the Arctic ice melts, competition for resources and influence in the region increases. Closer to the equator, rising temperatures and more frequent and intense extreme weather events in Africa and Central America threaten millions with drought, hunger and displacement.

As families risk their lives in search of safety and security, mass migration leaves them vulnerable to exploitation and radicalization, all of which undermine stability, he said. And in the far reaches of the Pacific, rising sea levels and more frequent and intense storms put individuals, families and whole communities at risk, while pushing the limits of the world's collective capacity to respond.

A person works with fire in a field.
Prescribed Burn
Forestry Technician Tim Parry lights a prescribed burn March 18, 2021, along the railroad tracks on South Post at Fort McCoy, Wisc.
Photo By: Scott Sturkol, Army
VIRIN: 210318-A-OK556-468

The Defense Department has been impacted directly in just the past few years by extreme weather caused by climate change, he said, providing some examples:

  • Hurricane Michael inflicted billions of dollars of damage at Tyndall Air Force Base in Florida.
  • Severe flooding of the Missouri River in the Midwest damaged Offutt Air Force Base, Nebraska, costing hundreds of millions of dollars.
  • Wildfires in California have threatened military installations, forcing repeated evacuations.
  • Typhoons in Guam most commonly occur from June to December, but in February 2019, Typhoon Wutip forced the DOD to pause exercises with Australian and Japanese allies.

The department has been called repeatedly to support communities throughout the United States and abroad, as they attempt to recover from severe weather events, Austin said.

A river flows past a lock and dam.
Flood Waters
Flood waters force closure of the Locks and Dams 3 on the Monongahela River in Elizabeth, Pa., March 1, 2021. High water from snow melts and extended rain affected the U.S. Army Corps of Engineers Pittsburgh District on the Monongahela River.
Photo By: Philip Delo, U.S. Army Corps of Engineers Pittsburgh District
VIRIN: 210301-A-XX123-004C

"From coast to coast and across the world, the climate crisis has caused substantial damage and put people in danger, making it more difficult for us to carry out our mission of defending the United States and our allies," he said.

That's why President Joe Biden has tasked the United States' 18 intelligence agencies with producing a National Intelligence Estimate on the security implications of climate change, he said.

"We in the Department of Defense are committed to doing our part, from increasing the energy efficiency of our platforms and installations, to deploying clean distributed generation and energy storage, to electrifying our own vehicle fleets," he said, adding that "we're not alone," meaning allies and partners are also addressing the threat.

People mill about in the snow, There is a helicopter in the background.
Community Meeting
Community members of the city of Chevak, watch from a safe distance as representatives from of the Alaska Department of Military and Veterans Affairs, the Department of Environmental Conservation and the Department of Commerce, Community and Economic Development load onto an Alaska Army National Guard UH-60 Black Hawk helicopter in Chevak, Alaska, April 9, 2021. Members of the Alaska Department of Military and Veterans Affairs, the Department of Environmental Conservation and the Department of Commerce, Community and Economic Development traveled to western Alaska April 7-9 to meet with tribal leaders and citizens in Bethel, Tuluksak and Chevak to discuss disaster assistance measures and processes in light of recent emergencies that have occurred in the region, and in preparation for the upcoming flood season.
Photo By: Dana Rosso, Army National Guard
VIRIN: 210409-Z-PB632-0101C

The Climate Change and Sustainability Strategic Approach recently issued by the United Kingdom raises the bar on how militaries can adapt to an operational environment that considers the effects of climate change while advancing military capabilities and resilience, he said.

"The benefits of action extend well beyond the climate, and include opportunities to improve our own operations. For example, when we operate more sustainably, we become more logistically agile and ready to respond to crises," he said.

A helicopter dumps a bucket of water into a river.
Water Bucket Training
New York Army National Guard helicopter pilots, crews and soldiers with 3rd Assault Helicopter Battalion 142nd Aviation Regiment, 42nd Combat Aviation Brigade, 42nd Infantry Division, conduct water bucket training using UH-60M and UH-60L Black Hawk helicopters at Camp Smith Training Site and over the Hudson River next to Iona Island, N.Y., April 6, 2021.
Photo By: Sgt. Sebastian Rothwyn, Army National Guard
VIRIN: 210406-A-RV314-448C

"We also have a once-in-a-generation opportunity to build an entire economic sector and the global infrastructure for clean energy. The truth is that our shared commitment will allow us to create a safer, more resilient, secure and sustainable future," he said.

"None of us can tackle this problem alone. We share this planet, and shared threats demand shared solutions. I look forward to working with all of you on this vital mission," he concluded.

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