Heatwaves and H-Bombs: The Nuclear Triad’s Vulnerabilities to Climate Change

By Shawn Rostker

Sunday, July 21, brokethe record for the hottest day recorded on Earth in modern times. The following day, that record was broken again.

Extreme weather events like this are occurring more frequently and with greater intensity than during any other period of recorded human existence, and the cumulative effects of climate change pose an existential threat to humanity that may not be as immediate as that posed by nuclear weapons, but are just as important.

Unfortunately, the relationship between climate change and nuclear weapons policy remains underappreciated and underexplored. Future conflicts induced by climate change could leadto global instabilities and greater reliance on military force, likely elevating the role of nuclear weapons in security strategies. There is no longer any doubt: nuclear and climate risks are inextricably linked and mutually interferent. Choices made today, including which nuclear modernization programs to pursue, what kind of force structure and posture to establish, and what arms control policies to prioritize will all have consequences in a world physically and socially redefined by climate change. Making informed decisions requires understanding how each leg of the nuclear triad may be affected by a changing climate.

Land-based elements of the U.S. nuclear triad could face flooding and fire risks. Intercontinental ballistic missile (ICBM) silos and facilities across North Dakota, Wyoming and Montana will be at greater risk of floodingevents due to warming temperatures that increase regional precipitation and average snowmelt runoff. A significant flood can inundate missile silos, their associated command and control facilities, and the critical infrastructure connecting them. The 2011 Souris River flood, for example, damagedaccess roads that made several ICBM launch facilities inaccessible and displaced base personnel living nearby. A future flooding event could thus disrupt ICBM operations by reducing force readiness and delaying staff rotations. Additionally, the Nuclear Security Enterprise - the consortium of facilities responsible for the stewardship, modernization and security of U.S. nuclear weapons - faces increased wildfire risks. In March 2024, wildfires in the Texas panhandle forcedthe temporary shutdown of the Pantex plant, the primary site where nuclear weapons are assembled and disassembled and plutonium fuel from retired nuclear warheads is stored.

The air leg of the nuclear triad faces dangers from extreme heat. Whiteman Air Force Base in Missouri, home to U.S. nuclear-capable B-2 bombers, is projectedto experience as many as 16 times more annual days with temperatures exceeding 100 degrees Fahrenheit. This would mean more "black flag"conditions in which personnel activities are significantly restricted or halted. More such days will mean reduced training and operational capacities, affecting everything from the number of hours pilots get in the cockpit to the basic upkeep of the base's nuclear storage facilities. Moreover, extreme heat may impact the aircraft themselves. B-2s are ratedto withstand temperatures up to 120 degrees Fahrenheit and could require grounding in temperatures greater than this. As the effects of climate change intensify, the air leg of the nuclear triad will come under increased strain and will likely require greater resources to ensure operations remain safe and uninterrupted.

Perhaps the most important element of U.S. nuclear deterrence, the sea leg of the triad will likewise encounter the effects of climate change. Naval Base Kings Bay in Georgia is at risk from rising sea levels and flooding that could damage support infrastructure and hamper ballistic missile submarine (SSBN) service efforts. As sea levels rise, the risk of storm surges increases, which can inundate docks, maintenance facilities, and nuclear weapons storage areas and transport roadways. Ocean encroachment could thus impact base accessibility and disrupt scheduled SSBN and warhead maintenance. Operational disruptions at one SSBN base could reverberate across the broader deterrence mission of the submarine fleet, resulting in undue strain upon the sea leg of the triad.

While these climate effects are cursory and don't capture the full extent of the climate-nuclear challenge, they do represent very real possibilities that the United States may confront and indeed, in some cases, alreadyis confronting.

But the United States is not alone in facing this challenge. Russia has experiencedthe effects of climate change upon its nuclear establishment and both Pakistan and India have weathered the strain of unprecedented floodingand heatwavesin recent years. North Korea, as well, recently sustained severe flooding that reportedly damagedweapons facilities connected to the country's nuclear program. As global nuclear relations fray and competition ramps up, climate change could be a neutral and unifying issue on which cooperation can help open up space for nuclear arms control and other de-risking strategies.

Responsible and prudent decisions on nuclear weapons policy must account for the twin threatof climate change, as there are significant geopolitical, financial and opportunity costs to consider. The relationship between the two is something that all nuclear weapons states must explore with greater urgency before it's too late.