The Next Security Frontier

By Captain Jonathan S. Spaner, U.S. Coast Guard, and Hillary LeBail

What is Climate Change?

Climate change is unlike any other threat to our national security. Compared with threats such as transnational organized crime or terrorism, climate change is not an enemy our government encounters in the traditional sense. You cannot attack a marauding hurricane or arrest the rising tide. Regardless of our best efforts, climate change will forever alter the operating environment of our nation’s military and homeland-security components. Therefore, it is vital that we understand exactly what is meant by the term climate change and how it is likely to affect our mission readiness and homeland security.

The President’s National Security Strategy , the Quadrennial Defense Review , the Quadrennial Homeland Security Review , as well as the National Intelligence Council, Central Intelligence Agency, and Government Accountability Office, among others, have identified climate change as a security threat. Some may question whether labeling a few weather phenomena as threats to security is necessary or appropriate; however, to understand the reasoning we must first understand the concept of climate change itself. There is a distinct difference between the terms weather and climate . In its simplest terms, weather is short-term and locally focused—what an individual observes when he or she looks out the window on any given day. Climate refers to trends in weather over a considerable period of time, typically ten years or more. Security strategists and policy makers are referring to these longer-term observations when discussing climate change and its impacts.

The greenhouse effect drives climate change as we experience it today. Think of the Earth wrapped in a blanket composed of greenhouse gases in the atmosphere, which keep the Earth warm and allow our planet to sustain life. As more greenhouse gases enter the atmosphere, such as carbon dioxide and methane, this blanket becomes thicker and more effective, heat is retained, and the Earth’s overall temperature increases. Whether caused by natural or human circumstances, these increases in temperature, more commonly known as global warming, can have a significant and lasting impact on climate.

In May, researchers measured carbon dioxide concentration in the atmosphere at 400 parts per million—the highest levels ever recorded. 2 Moreover, scientists have demonstrated through analysis of the Earth’s history that such carbon dioxide levels correspond directly to higher temperatures, melting polar ice and mountain glaciers, and rising sea levels. Over time, the planet will try to cool itself naturally and reduce the amount of excess heat present in its atmosphere. In so doing, our planet creates a long-term trend of unpredictable weather, from severe storms to droughts, a phenomenon also known as climate change.

Impacts of Climate Change

The President’s Climate Action Plan says climate change represents one of the greatest challenges of our time, but one suited to America’s strengths. The plan, announced in June, contains three key pillars: cutting carbon pollution in America; preparing the United States for the impacts of climate change; and leading international efforts to combat global climate change and prepare for its impacts. 3

The second and third pillars of the plan focus primarily on adaptation efforts and the need to understand the effects of climate change both within the United States and around the world. Perhaps nowhere else are the impacts more noticeable than in the Arctic. Temperatures are warming twice as fast within the Arctic Circle than anywhere else, and during summer months a new ocean is beginning to emerge. The melting of sea ice is largely due to the natural circulation of air and ocean currents that move heat energy away from the equator and toward the Poles. Ice and snow reflect heat into space and help cool the Earth, but as sea ice melts, the oceans absorb even more heat energy and carbon dioxide. Moreover, melting permafrost and warming waters release methane, a far more potent greenhouse gas than carbon dioxide. Combined, these effects further accelerate the warming of the planet.

In September 2012, the Arctic sea ice minimum was at its lowest extent and thickness since satellite observations began in 1979. The U.S. Coast Guard has already had to establish a mobile seasonal presence in the Arctic due to increased activity and recently released its Coast Guard Arctic Strategy to guide future efforts. Its three strategic objectives are improving awareness, modernizing governance, and broadening partnerships. These attempt to address the many realities emerging in this geo-strategic environment, including indigenous rights, increased shipping, migrating fish stocks, new transportation routes, and remarkable opportunities for oil, gas, and mineral extraction. Changing conditions have increased our military’s area of operations in a constrained budget environment. Operational capabilities must be present to ensure safe, secure, and environmentally responsible maritime activity in the Arctic, and we must plan strategically to fulfill this vision. 4

As climate change continues, extreme and unpredictable weather events are expected to increase in frequency and intensity. The Department of Homeland Security has always fulfilled its emergency-response missions during times of disaster, and this area of responsibility will increase as extreme weather events such as severe storms, hurricanes, and floods—fueled by warmer temperatures—endanger the lives of Americans. These events occur with catastrophic costs to the federal government and further strain the capabilities of our military, which is already fulfilling missions elsewhere in the country and around the globe.

Sea-level rise as a result of climate change affects many of the oceans where our forces operate. It occurs slowly, which means it is often overlooked as a threat, but has the potential to be one of the most significant of all related consequences. As the oceans absorb heat trapped in the atmosphere, the newly warmed water expands and causes a corresponding rise in sea level. In addition, melting ice, especially the massive West Antarctic and Greenland ice sheets, contributes to rises in sea levels. Throughout the past century, sea level has risen between four and eight inches, and satellite data have shown that more than 2.3 inches of these observed changes have occurred in the past 20 years. 5 Even a few inches can have a substantial impact in coastal areas, and although there is scientific uncertainty as to how fast and how much sea levels will rise, some coastal cities and islands are facing a dire future.

For many coastal and island communities, sea-level rise, coastal erosion, flooding, and contamination of fresh water supplies are major concerns. Public installations flooded by rising water levels might be required to relocate or rebuild certain structures if impacts increase in severity. Strains to these security facilities, power systems, water and sanitation supplies, highways, and communication networks, whether it be the result of extreme temperatures or flooding, can greatly affect the ability of armed services and constabulary forces to carry out their missions.

Larger storm surges during extreme weather events are also a cause for concern. During Hurricane Sandy, Battery Park in New York saw a record-breaking storm surge of 13.88 feet—far greater than the previous record of just over 10 feet during Hurricane Donna in 1960. Such events have required an increased presence of crisis managers, especially those of the U.S. Coast Guard, for search and rescue and port reconstitution. Restarting trade is especially critical for economic stability. Even bridges over tidal estuaries and rivers are susceptible to a rise of just a few inches in sea level. While they may currently be up to code, some bridges might not be able to structurally withstand greater rises in levels. Commercial and/or military vessels that could once pass safely underneath a bridge may, in the future, find that safe passage is not possible without some modification.

A Threat Multiplier

When asked about the greatest long-term security threat to the Pacific region, U.S. Navy Admiral Samuel J. Locklear III, Commander U.S. Pacific Command, responded with climate change. 6 This is a unique problem for national security, because it acts as a threat multiplier, a concept that senior defense officials are recognizing and about which they are concerned. Stressors that already exist in the world, particularly in the Western Hemisphere, are or will be touched in some way by climate change. Whether it is poverty, food and water scarcity, diseases, economic instability, or the threat of natural disasters, the broad range of changing climatic conditions may be far reaching.

These challenges may threaten stability in much of the world. As temperatures increase, so too may aggression, violence, and international conflict. Studies show that climate shifts have historically been associated with violent encounters. The Mayan civilization fell during an excessive period of drought, and most Chinese dynasties collapsed during dry spells. 7 Droughts, tropical storms, and violence among or within nations could lead to increased population movements, both legally and illegally. Short-term disaster-driven migration and environmental refugees could create new homeland security challenges. These population movements might include illicit markets and activity across the U.S. border, including transnational organized crime and terrorism.

Food security and competition for resources is another concern driven by climate change. As shifts in temperature and rainfall impact agricultural productivity in vulnerable areas, food scarcity and high prices could incite discontent and force the displacement of populations. 8 Seafood in particular is an important protein resource for much of the world. As ocean temperatures increase and ocean waters become more acidic, reefs and other marine ecosystems are going to be degraded. As a result, populations of marine life will migrate to new and more hospitable locations— with no regard for international boundaries or exclusive economic zones. Illegal, unreported, and unregulated fishing may increase as current fishing grounds become less productive, new grounds become available, and disputes arise over competition for migrating resources. A constabulary presence will be necessary to monitor, enforce, and protect the safety, security, and environmental sustainability of these regions.

A Changed Security Environment

Four days following the 1983 terrorist attacks against the Multinational Force in Beirut, Lebanon, President Ronald Reagan said,

There was a time when our national security was based on a standing army here within our own borders . . . and, of course, a navy to keep the sea lanes open for the shipping of things necessary to our well-being. The world has changed. Today, our national security can be threatened in faraway places. It’s up to all of us to be aware of the strategic importance of such places.

President Reagan’s statement is as true today as it was 30 years ago. Not unlike past efforts to confront fascism, communism, terrorism, or other security challenges, climate change will require our attention for generations to come.

Indeed, this is an underlying factor for many threats and matters of security including disaffection of populations, border security, strenthening communities, and crisis management. Education is an important first step in preparing to confront climate change, and with awareness of the threats, we can then agree on a future course of action.

We must continue encouraging awareness to ensure a full appreciation for these threats. With respect to homeland security in particular, future strategies may consider measures to enhance climate adaptability in communities, leverage lessons-learned from extreme storms to update flood risk-reduction standards, build public infrastructure such as hospitals to withstand storms and rising sea levels, and increase multinational engagement to build global resilience. As with other homeland-security strategies, community preparedness and partnerships will be imperative for success, and it is our hope that we take time as a nation to contemplate major challenges posed by climate change and plan strategically. Regardless of the cause, the climate is changing, and we must be prepared.

1. Intergovernmental Panel on Climate Change, Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change , Geneva, Switzerland, IPCC, (2008), .

2. Justin Gillis, “Heat-Trapping Gas Passes Milestone, Raising Fears,” The New York Times , 10 May 2013, .

3. See .

4. U.S. Coast Guard, Coast Guard Arctic Strategy , Washinton DC, 2013, .

5. National Aeronautics and Atmospheric Administration, “Global Climate Change,” 2013, .

6. Will Rogers, “Climate Change Tops List of Security Threats in Pacific, says ADM Locklear,” Center for a New American Security Blog , 11 March 2013, .

7. Elizabeth Landau, “Climate Change May Increase Violence, Study Shows,” CNN , 2 August 2013, .

8. Ibid.

Captain Spaner is Director of Emerging Policy in Washington, D.C., where he is responsible for strategy on major issues including the Arctic, Western Hemisphere affairs, and climate change. He holds an MBA from MIT and is a former White House Fellow.

Ms. LeBail is a Presidential Management Fellow assigned to the Coast Guard’s Office of Emerging Policy.




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