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Why Climate Change is a Threat to National Security

By: Katherine Youssouf

Natural disasters and weather conditions exacerbated by climate change are the most prevalent threats faced by the United States government, the private sector, and the public. As greenhouse gas emissions intensify, sea-levels will continue to rise, average global temperatures will increase, and severe weather patterns will accelerate, all of which will cause significant challenges for the protection of domestic infrastructure and American livelihoods. Since 1980, 241 climate disasters have wreaked havoc on U.S. territories, amounting to a total cost of $1.6 trillion in damage. Over the last nine years, the Department of Defense (DOD) has published at least thirty-five products explicitly addressing the threat of climate change. Congress, in its National Defense Authorization Act for fiscal year 2018, called climate change “a direct threat to the national security of the United States.” Moreover, the United States Army, Navy, and Marine Corps all agree that the effects of climate change threaten the future security environment by hindering military readiness and damaging domestic infrastructure.

From a defense perspective, climate change shapes the environment in which military agencies operate and the missions in which they engage. For instance, between 2013 and 2015, DOD reported that at least one military site in every state had been negatively impacted by climate-related effects. In January 2019, DOD reported that seventy-nine domestic military installations had been impacted by and remain vulnerable to five specific types of climate-related effects: recurrent flooding, drought, desertification, wildfires, and thawing permafrost. Military installations are essential to supporting military readiness because they are the facilities from which members of the U.S. armed forces deploy and on which they train and live. However, these facilities become unusable or require costly or manpower-intensive work when affected by extreme weather conditions. For instance, after Hurricane Michael’s 130 mile per hour winds tore through Florida’s panhandle, Tyndall Air Force Base—which houses the headquarters of the Florida National Guard and is the principal training center and testing site for F-22 Raptor pilots, crew, and equipment—was unable to regain normal operating status for nearly a month. During this time, critical training and maintenance schedules for almost a third of the nation’s F-22s were disrupted, forcing the fighter jets to relocate. Recovery since then has been costly and time consuming.

Rising sea-levels due to global warming are projected to put nearly 130 military bases at risk of damage from tidal floods and storm surges. By 2050, military installations along the East Coast are predicted to experience ten times the number of floods they experience today, which will also affect the surrounding communities. By 2070, many of these sites could experience more than 520 annual floods, and by the end of the century some will have lost of up to 95% of the land on which they exist. Other military installations, particularly those engaged in airfield operations, are imperiled by intense winds, wildfires, droughts, and erosion as a result of climate change. Additionally, military facilities overseas in areas with increasing frequency and intensity of heat waves, precipitation, and flooding experience a higher number of black flag days, which require all non-mission essential training and strenuous exercise to be suspended for all personnel.

Climate change also influences the operating environment, roles, and missions that the military undertakes at home and abroad. For instance, in its Climate Change Adaptation Roadmap, DOD predicted that the effects of climate change will demand military support to civil authorities and enhanced humanitarian assistance in the face of increasingly frequent and intense natural disasters. In 2017, after the devastation of Hurricane Harvey, which three separate studies attribute to climate change, 14,000 reserve forces were activated to assist in search and rescue missions and other emergency-related operations. DOD further predicts that climate change will intensify the challenges of global instability, hunger, poverty, and conflict. For this reason, DOD has characterized climate change as a “threat multiplier,” which will exacerbate social and economic stressors, including food and water shortages, disease, disputes over refugees, and resource competition. In turn, these outcomes will increase the risk of political instability, social upheaval, and violence abroad, often in fragile or volatile regions in which U.S. armed forces are already deployed.

The frequency of natural disasters is only expected to increase in the coming decades, as greenhouse gases remain in the atmosphere for over 100 years. As such, the U.S. federal government must take necessary preventative measures to ensure that its domestic infrastructure is equipped to respond to the effects of extreme weather conditions in the future. The far-reaching effects of climate change on national security demand that each branch of government take an active role in reducing U.S. greenhouse gas emissions and supporting the transition to clean energy. For instance, Congress can act through its plenary powers under the Commerce Clause to enact legislation that restricts environmental degradation. Two of the most successful pieces of environmental legislation have been the Clean Air Act of 1970 (CAA), which delegates authority to the Environmental Protection Agency (EPA) to set standards for the release of toxic air pollutants into the “ambient air”; and the Clean Water Act of 1972, which gives the EPA the authority to set standards for the types of pollutants that can be released into lakes, streams, and rivers. Unfortunately, these laws were both adopted by large Democratic majorities in Congress, and since then most attempts at legislating reductions in greenhouse gas emissions, such as the Waxman-Markey Bill, which would have established a nationwide carbon-trading scheme, have failed.

Some executive branch agencies, like the Army Research Office (ARO) and the Defense Advanced Research Projects Agency (DARPA) within DOD, are actively developing policies to manage and respond to the effects of climate change, particularly on issues of national security. However, DOD policies will only go so far, especially when the position taken by President Trump is consistently at odds with the research put forth by his armed forces. Indeed, even the president’s former secretary of defense, James Mattis, recognized climate change as a national security threat. It is difficult to foresee how DOD factions will be able to ensure the future security of the nation when its own resources are attacked by climate-related effects and neither the president nor the majority of Congress is willing to acknowledge the threat that climate change presents. For these reasons, the courts may be the only institutional option through which Americans can realistically hope to bring about environmental justice and positive change. Federal courts in particular can interpret existing environmental legislation, as the Supreme Court did in Massachusetts v. EPA, and provide a venue for states, industry, and citizens to challenge climate measures. In fact, a growing number of citizens and communities are using the courts to seek relief from the detrimental effects of increased carbon dioxide emissions. In Juliana v. United States, twenty-one young plaintiffs–the youngest of which is eleven years-old–are suing the federal government to seek injunctive relief against new fossil fuel extraction on government territory. Given the effects of climate change on the future security environment, how the courts decide these cases will not only influence industry, policy, and law, but also U.S. national security.


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