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New Briefer: Why the U.S. National Security Community Takes Climate Risks Seriously

ClimateSecurity101_LOGOBRIEFER No. 30 | December 13, 2016

[UPDATE]: Climate and Security 101: Why the U.S. National Security Community Takes Climate Risks Seriously (PDF)

In 2007, former Army Chief of Staff, retired General Gordon R. Sullivan, stated:

“People are saying they want to be perfectly convinced about climate science projections…But speaking as a soldier, we never have 100 percent certainty. If you wait until you have 100 percent certainty, something bad is going to happen on the battlefield.”

The national security establishment in the United States, including the military, intelligence and homeland security communities, understand climate risks as a national security challenge, and that the United States cannot wait for 100% certainty before acting to address them. This is due to the nature of climate change as a “threat multiplier,” which exacerbates existing and pending challenges in the security landscape. The security community has been planning for these risks since the first term of the George W. Bush Administration. This includes integration of climate risks into close to 70 unclassified defense, intelligence and homeland security assessments, strategies and plans since 2003. During the G. W. Bush Administration alone, eight major unclassified documents from the defense and intelligence community warned of climate risks to key national security equities:

2003: Pentagon Office of Net Assessment: An Abrupt Climate Change Scenario and Its Implications for United States National Security.

2003: Air War College: Weather Operations in the Transformation Era.

2007: Department of the Navy, the Marine Corps and the Coast Guard: A Cooperative Strategy for 21st Century Sea Power.

2007: CNA Military Advisory Board: National Security and the Threat of Climate Change:

2008: United States Joint Forces Command: The Joint Operating Environment, Trends and Challenges for the Future Joint Force Through 2030

2008: National Intelligence Council: National Intelligence Assessment (NIA) on the National Security Implications of Climate Change to 2030.

2008: Department of Defense: National Defense Strategy.

2008: National Intelligence Council: Global Trends 2025: A Transformed World.

In short, attention to climate risks by the U.S. national security community spans administrations and transcends political party lines. But why? Why do those organs of government that the public normally associates with fighting the nation’s wars, devote time and effort to a problem that is popularly perceived as a primarily “environmental” issue, and is often framed a partisan issue?

The simple answer: climate change risks are broadly considered to be a national security threat, and this assessment enjoys bipartisan support in the national security community. In 2016, for example, a group of senior military and national security leaders convened by the Center for Climate and Security, many of whom served under both Bush Administrations, and the Reagan Administration, determined that climate change presents a “strategically-significant risk” to national security, and that it requires a commensurate level of response.

For the national security community, changes in the climate present problems worthy of attention by those whose primary job it is to protect the United States, and its allies, from physical harm. The following is a brief outline of how and why the U.S. national security community treats climate risks the way it does, starting with:

  • The common definition of a national security threat, and how climate risks fit into that definition;
  • The direct and indirect national security implications of climate risks;
  • Why a changing climate warrants attention as an exacerbator of other national security threats.

The definition of a national security threat, and how climate change fits into that definition

Unfortunately there is no one, accepted definition of a national security threat. However, simply put, the national security community generally categorizes threats as either: direct, physical threats to the U.S. homeland, or vital U.S. assets and personnel abroad; or indirect threats from regions of the world that are either of strategic interest to the United States, or whose instability could ultimately lead to direct threats to the United States. In this context, the national security community considers climate change a “threat multiplier” (a term first coined by CNA’s Military Advisory Board and now broadly used by the U.S. Department of Defense [DoD]), or an “accelerant of instability” as its characterized in the FY2010 Quadrennial Defense Review report conducted by the DoD. This means that climate change exacerbates, or heightens, other threats to the United States. In other words, the cumulative impact of a changing climate alters the security landscape.

Multiplying direct threats to the U.S. homeland

Numerous climate projections highlight a future of increased extreme weather events, such as droughts, floods, storms, and sea level rise in North America, which could devastate coastal communities, energy facilities and areas of the United States that rely on predictable patterns of rainfall. This puts U.S. domestic military installations and the civilian infrastructure and logistical chains essential to those installations at risk, and this has become a major concern for the DoD. For example, the DoD has determined that drought, dust storms, forest fires, and rising temperatures are physically affecting military bases and training ranges across the American Southwest. DoD has also examined the impact of sea level rise on its numerous coastal military installations (including the highly vulnerable Hampton Roads region, which includes 29 military sites that are critical for U.S. military readiness), concluding that these risks are real and increasing. An independent review by a Military Expert Panel convened by the Center for Climate and Security, concluded that sea level rise presents “serious risks to military readiness, operations and strategy,” based on existing and projected impacts of sea level rise and storm surge on critical military infrastructure and associated civilian support structure, including access roads and energy grids.

Multiplying direct threats to military installations and U.S. forces abroad

U.S. military installations abroad are at serious risk of climate-related impacts, particularly critical coastal bases on low-lying islands like Diego Garcia. A 2016 DoD SERDP report ran sea level rise scenarios for 1,774 costal military bases worldwide, and found significant risks at all times scales examined (2035, 2065, and 2100).

Heightened droughts, or unpredictable rainfall patterns due primarily or in part to climate change in areas of the world where the U.S. military operates, can also leave armed forces vulnerable to being disconnected from potable water supplies. Protecting convoys to transport available water (along with protecting fuel convoys, which accounted for “one-third of U.S. Army casualties in Afghanistan in 2007”), is a dangerous mission for troops to engage in. That’s why the DoD works to equip its soldiers with portable water filtration, and water desalination devices to deal with the problem, along with mobile hybrid and renewable energy systems (see for example, the U.S. Army’s Energy to the Edge program). The emphasis is on enhancing the military’s warfighting capability, not addressing climate change.

Multiplying indirect threats in regions of the world that are either of strategic interest to the United States, or whose instability could ultimately lead to direct threats to the United States

Much of the national security community’s concern about climate change revolves around its capacity to multiply indirect threats to the United States or its interests, particularly in regions of the world that the U.S. either sees as key, strategic environments or those whose instability could constitute a threat to the U.S.

For example, climate change threatens to indirectly upset the balance of competing interests in the South China Sea, an area of critical geostrategic importance to the United States. where ships carry $1.2 billion in U.S. trade annually. On top of this, sovereignty over parts of the Sea is bitterly contested by adjacent countries, and the U.S. and China have perennially competed over its control (with the U.S. viewing Chinese expansionism in the sea as a threat to national security, and the security of key allies). As the ocean warms, and fish stocks move northward, tensions between the fishing fleets of China and other regional nations will increase, potentially heightening the possibility of conflict.

During his tour of duty as the Commander of U.S. Pacific Command (PACOM), Admiral Samuel J. Locklear III identified climate change as the biggest long-term security threat facing the Asia-Pacific region. As Admiral Locklear stated, in reference to the climate threat to growing coastal populations in the Asia-Pacific region: “If it goes bad, you could have hundreds of thousands or millions of people displaced and then security will start to crumble pretty quickly.” A security breakdown in such a strategically-significant part of the world could have a significant impact on U.S. national security interests.

Climate change may also place stresses on food security by increasing the severity, frequency and variability of crop-damaging events like droughts and floods. Because of the nature of the global food market, this can sometimes result in spikes in world food prices, increasing the likelihood of instability in places that depend on affordable imported food, such as most of the Middle East and North Africa. This is part of a larger phenomenon Dr. Troy Sternberg calls “the globalization of hazards,” where natural hazards in one region can have a significant impact on regions halfway across the globe. In the case of countries such as Egypt, that are of such strategic significance to the U.S, such chronic instability due in part to severe food insecurity can fundamentally change the global security architecture that the U.S. defends.

In the Arctic, dramatic changes to sea ice cover, driven in large part by climate change, may have a significant impact on resource disputes, particularly given a petroleum-rich sea bed and hazy territorial boundaries. The expected increase in commercial activities in the Arctic may also lead to security complications – as nations attempt to manage large stretches of open ocean that were previously inaccessible.

Lastly, climate change can exacerbate the social, economic and environmental stresses that plague fragile states, thus heightening the probability of massive population displacements, and instability. In Syria, a severe drought from 2006-2011, coupled with severe natural resource mismanagement by the Assad regime, and other stresses, led to the displacement of around 1.5 million farmers and herders. As we noted in our report “The Arab Spring and Climate Change,” this drought was part of a pattern of increased drying in the Mediterranean and Middle East beginning in 1973, which was strongly associated with climate change in a 2011 NOAA report. Though it would be folly to argue that climate change “caused” the Syrian civil war, it is clear that the region’s plummeting winter precipitation levels was one of the drivers of massive population displacements in Syria, and that the inadequacy of the government’s response to that displacement contributed to popular dissatisfaction with the Assad regime.

In short, climate change threatens to make fragile states even more fragile, which can lead to the potential for de-stabilizing violence, which can present direct security challenges to the United States and its allies. This concern is so acute that the U.S. DoD is actively investing resources (including through the Minerva Initiative) to comprehensively map the security implications of climate change in Africa and South Asia – two regions of increasing strategic interest to the U.S, due to rising powers, increases in refugee flows, the rise of transnational terrorist organizations, and other security risks.

Why a changing climate warrants attention as an exacerbator of other national security threats

Do these security threats really warrant serious attention in light of the plethora of other security threats, like the proliferation of nuclear weapons and materials? From a U.S. national security perspective, the answer is yes – not least because climate stresses on food, water and energy systems can make other security threats worse, particularly in fragile and climate vulnerable regions, such as the Middle East and North Africa, Central and South Asia. In this context, it is not useful to separate climate risks from other risks, or to attempt to rank it against other threats. It is, as mentioned previously, a “threat multiplier”, increasing the degree of risk posed by other more traditional risks. Furthermore, climate change is what risk analysts would call a “high probability, high impact” risk, meaning that it is very likely to occur (between 90 and 97%), and will have a very large and widespread impact on security (for example, the 2014 Global Risks Report ranked climate change highest, next to “fiscal crises,” in this regard).

It is useful to compare this to another transnational risk – the proliferation of nuclear weapons. A study commissioned in 2005 by Senator Richard Lugar produced a median response of a 10 percent likelihood of “an attack involving a nuclear explosion” in five years and a 20 percent likelihood in 10 years. Of course, in the case of a nuclear detonation, the price of that 10 or 20 percent likelihood materializing is devastating and unacceptable, so it makes all the sense in the world to prevent it. The same goes for a changing climate, given the high degree of certainty about its occurrence, and the likely scale of its impact over time.


The national security community doesn’t have the luxury of waiting for 100% certainty about the scope, scale, or causation of climate change before addressing the associated risks, any more that it can wait for such certainty with any other national security risk. There is already a sufficiently high degree of certainty that climate change is, and has the capacity to be, a multiplier of direct and indirect threats to the United States, and that steps to address that risk are warranted. That’s why U.S. national security planners put time, personnel and resources into addressing its effects, and have done so across both Republican and Democratic administrations. In this context, climate change as a security risk is not just a narrative, or a political talking point. The U.S. military, intelligence and homeland security communities – indeed, the US government as a whole – have an obligation to be prepared for and work to shape the entire geostrategic and domestic security environment, and cannot afford blind spots in that picture.

*This is an update of the 2012 and 2014 Briefers on Climate Security 101. For more information on the nature of climate risks see The Climate Security 101 Project.

1 Comment

  1. Dr. Vlad Fomin says:

    Congratulations Merry Christmas Jesus Christ! Take the best wishes and success in your work! I really want a stable climate in the world without the risks of our lives. Yours faithfully!!

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