Environmental security intelligence: the role of US intelligence agencies and science advisory groups in anticipating climate security threats

ABSTRACT

Science advisory groups have long played significant roles in federal policy- and decision-making. This article examines the history and importance of science advisory groups in conducting research and advising government administrations on matters of climate change risks and environmental security. Climate change will continue to act as a threat multiplier, amplifying these risks and their effects on security and society. The government science advisory group MEDEA and its contributions to environmental research and national, societal, and environmental security analysis are presented as a model of partnership between the scientific and intelligence communities. The history, research, and environmental expertise of the MEDEA program are discussed in the security context, including an examination of its relationship with the intelligence community. Finally, historical examples are provided to suggest how future science advisory groups can provide informed guidance and contribute to federal security objectives.

KEYWORDS:

• MEDEA
• climate change
• environmental intelligence
• environmental security
• remote sensing
• science advisory groups
• threat multiplier

Introduction

Science advisory groups have a long history of working with the executive branch of government. In December 2000, the government science advisory group MEDEA released the report Environment and National Security: Key Issues for the New Administration. The report described MEDEA’s achievements in the 1990s and outlined environmental security considerations for the incoming George W. Bush administration. The report emphasized the near-term policy and security implications of multiple environmental issues, ranging from natural disasters and social stability to regional sustainable development and international environmental agreements. It also called for greater integration of science advisement into the Intelligence Community (IC).¹ Subsequent administrations continued to receive science-based reporting and analysis of climate change issues and progression.

This article discusses the role of science advisory groups in environmental research and policy development through the lens of the MEDEA program and its partnership with the IC. MEDEA helped anticipate security challenges linked to climate change through its research and advisory roles. More than 50 years after the President’s Science Advisory Committee counseled the Johnson administration on the criticality of addressing the increasing effects of global warming,² the implications of climate change are pervasive and environmental security risks are mounting globally. In October of 2021, the US Government officially acknowledged environmental degradation as a major threat to the nation’s security. The Biden administration released a National Intelligence Estimate (NIE)³ that placed climate change at the heart of America’s security planning.

The environmental task force and MEDEA

Both the Allied forces and the Germans conducted World War I and II photoreconnaissance airplane flights and photogrammetry efforts to procure site specific photos for strategic combat advantage. During the Cold War, the United States incorporated new technology and launched dozens of reconnaissance satellites to assess the Soviet nuclear arsenal and capabilities, gathering photographs of wide swaths of land across the globe. After the war ended, a question presented itself: could the classified Cold War satellite imagery be of value to science? This question led to the establishment of the Environmental Task Force (ETF) and then MEDEA (which is not an acronym), named after the character in Greek mythology who helped Jason fight the Argonauts and steal the golden fleece.

In the early 1990s, hydrologist Jeff Dozier caught the attention of Vice President Al Gore, then a US Senator, with writings on opportunities that reconnaissance satellite imagery held for science. Gore recognized scientists could assess the potential value of classified reconnaissance data for environmental and climate research.⁴ He contacted Robert M. Gates, the Director of Central Intelligence (DCI), and together with Dozier, geophysicist Gordon MacDonald, and Earth scientist D. James Baker created the ETF in 1992. The ETF was the country’s first designated collective effort between the IC and public scientists. Linda Zall served as the Central Intelligence Agency (CIA) liaison between the ETF (and later MEDEA) and the IC.

The ETF comprised a select number of leading US environmental scientists who were provided security clearances from top security agencies, including the CIA and the National Reconnaissance Office (NRO). ETF members reviewed classified Cold War reconnaissance satellite imagery to discern its utility and applicability to environmental research. The objective of the ETF was to determine whether the classified information could help answer particular scientific questions.⁵ In 1994, the ETF evolved into the MEDEA program.⁶

MEDEA was initially chaired by MacDonald, who had previously served on the President’s Science Advisory Committee under President Lyndon B. Johnson and the Council on Environmental Quality under President Richard Nixon, and then by atmospheric scientist Michael McElroy. The program involved an expanded number of leading scientists from diverse disciplines. All required top secret-level security clearances to review reconnaissance satellite imagery and other classified data. MEDEA scientists continued the ETF’s satellite imagery and data assessment work and, for security reasons, reviewed classified data in an underground, spy-proof facility in Washington, DC.⁷ MEDEA operated as an advisory group to the IC and other divisions of the US government to provide scientific expertise for specific requests and to advise on matters of national security.

MEDEA’s focus eventually shifted towards using the data to focus on the national security implications of environmental change. The program provided a ‘two-way street’ for knowledge-sharing between the scientific and intelligence communities, with the IC better understanding the implications of environmental change and the scientists gaining invaluable insight into longitudinal global effects of climate change. With the scientists’ environmental expertise and opportunities for open discussion between the two communities, the transfer of valuable information in both directions became possible.⁸ The IC helped MEDEA access data and imagery, which MEDEA used reciprocally to advise the IC on national security and global rates and effects of climate change.⁹

The scientific and intelligence communities both collect data but have different objectives. Scientists make knowledge widely available, giving other scientists further research opportunities. In contrast, the IC minimizes the dissemination of secure information. The IC tends to collect and process data for short-term use, while climate scientists tend to value longitudinal data.¹⁰ The MEDEA program achieved the common goal of using otherwise publicly inaccessible data and other intelligence for environmental and other scientific purposes. With access to classified data, MEDEA was designed to be a confidential science advisory group for the government and became an internal environmental ‘think tank’ for the IC.¹¹

The earliest journal article based on classified data available to MEDEA was a study by planetary scientist Thomas McCord. This article discussed the characteristics and flight path of a meteor which entered the Earth’s atmosphere in February 1994 over the Pacific Ocean. Much of the data McCord used came from reconnaissance and military satellites tracking the meteor until its explosion.¹² McCord and other early MEDEA scientists faced editorial challenges with top journals as they could not provide peer-reviewers with the classified data used in the studies.¹³ Some MEDEA members published results using classified or high-resolution satellite imagery dating back decades.¹⁴

Following early research success and advocacy by ETF and then MEDEA for declassification of assets for scientific and civilian use, on 24 February 1995, President Bill Clinton issued Executive Order (e.o.) 12,951. This e.o. declassified more than 800,000 satellite images of the Earth’s surface collected from 1960–1972 from three Cold War satellite programs: CORONA, ARGON, and LANYARD. According to a NRO press release regarding Executive Order 12,951, the declassified imagery was selected to minimize security risks while maximizing government and public value. The objectives of the declassified imagery included supporting environmental studies and other civilian purposes.¹⁵

The process of mass declassification protected national security while minimizing the revealing of US surveillance satellite capabilities. All released imagery was in sufficient resolution to be valuable for civilian use and scientific study but of significantly lower resolution than the original reconnaissance satellite imagery. In a 2009 National Research Council (NRC) report entitled Scientific Value of Arctic Sea Ice Imagery Derived Products, scientists described methods developed to create ‘literal imagery derived products’ to prevent foreign entities from reverse-engineering the process to create higher resolution imagery.¹⁶ With the historical imagery no longer classified, it could also be shared internationally for science diplomacy purposes, reinforcing multilateral dialogues with innovative science and technology for maximum intergenerational benefit.¹⁷

One of MEDEA’s most significant achievements was the creation of the Global Fiducials Program (GFP). The GFP is a global system of longitudinal data collection via remote sensing at approximately 530 environmentally sensitive or otherwise significant geographic locations worldwide. These environmental benchmarks are used for the long-term monitoring of processes, both natural and anthropogenic, associated with the causes or effects of environmental change.¹⁸ Scientists selected numerous Arctic sea ice sites and glaciers as well as biologically-sensitive areas to observe changes longitudinally and remotely. Researchers can use this remote sensing data to explore changes in land cover over time, making the GFP a valuable tool for climate change research. For example, glaciologist Robert Bindschadler used both GFP and declassified Cold War satellite imagery to determine the rate at which an Antarctic ice stream progresses towards the ocean.¹⁹ The GFP combines the data needs of environmental researchers with the nation’s advanced data collection capabilities in non-commercial systems.

Remote sensing for natural disaster and emissions monitoring

As the risks of climate change intensify around the world, effective and efficient early disaster detection and real-time disaster assessment are becoming increasingly critical. Scientists have used remote sensing in early warning systems for more than half a century. In 1965, the US Weather Bureau, now named the National Weather Service, used a combination of data gathered from unclassified satellite data, radar, and aircraft to provide early and accurate warnings to the city of New Orleans for Category 4 Hurricane Betsy, allowing for a full evacuation from the area.²⁰ In 1981, Dozier concluded that the flare of a small wildfire gives off an infrared signature similar to that of missile launches and oil field flares.²¹ In the 1990s, atmospheric scientist and ETF member (and later MEDEA chairman) Ralph Cicerone suggested using remote sensing technology, such as satellite-based infrared measurements, to monitor and detect wildfires. The diverse network of military and reconnaissance satellites equipped with infrared detectors can detect wildfires and missile launches equally well.²²

MEDEA continued wildfire studies, recognizing that remote sensing could provide critical advance warning to prevent small wildfires from spreading by targeting fire-fighting resources. MEDEA’s efforts to develop wildfire monitoring methodology greatly enhanced modern-day fire-fighting techniques and early warning systems for wildfire detection and volcanic eruptions. Before the 1995 Montserrat volcano eruption, MEDEA monitored volcanic activity and provided warnings that allowed the Island’s government to evacuate 4,000 people from the danger zone. The following year MEDEA scientists used reconnaissance and US Department of Defense (DoD) satellites to track raging summer wildfires in Alaska, as the Forest Service lacked sufficient aircraft and capability to chart the region.²³

Exacerbated by rising temperatures, areas stricken by drought are more vulnerable to larger, more-intense, and longer-lasting fires.²⁴ This vulnerability increases significantly with wildfire seasons lengthened by climate change. In November 2018, California experienced some of the deadliest wildfires in its history, with 83 deaths and more than 10,000 homes destroyed.²⁵ Australia’s 2019–2020 brushfires, unparalleled in Australian recorded history, burned numerous towns and more than ten million hectares of brush and outback forest land.²⁶ In 2020, more than 8,000 wildfires burned over four million acres of California in five months. In addition to the tangible losses that result from these natural disasters, there are national security dangers as well, including risks to military bases and operations. Owing to MEDEA’s advocacy for public access, previously classified satellite imagery collected over decades is now shared by NASA scientists to help firefighters track fires and map damage by comparing images documenting changes to the Earth’s surface. A number of wildfire detection and notification tools, such as MODIS and FIRMS, are now available to help locate and fight these fires before they spread. These tools incorporate MEDEA-developed methodologies such as early warning alert systems and infrared detection for these applications.²⁷

MEDEA’s monitoring work extended beyond natural disaster detection to greenhouse gas (GHG) emission compliance. In 1997, the United Nations (UN) Framework Convention on Climate Change’s (UNFCCC) Kyoto Protocol became the first legally binding international agreement for countries to lower their GHG emissions. The US initially signed the agreement, before backing out in 2001. GHG emission compliance verification was challenging, as countries were only required to self-report measurements. The US sought a method to monitor and verify the treaty compliance by other nations for GHG emissions.²⁸ MEDEA supported several NRC reports on GHG emissions monitoring and other climate change-related security topics. A 2010 NRC report, Monitoring Climate Change Impacts: Metrics at the Intersection of the Human and Earth Systems,²⁹ recommended best practices for measuring GHG emissions and other metrics of climate change. In addition to reconnaissance and military satellites, new satellites capable of Earth data-collection were in orbit, including communication and weather satellites. Another 2010 NRC report, Verifying Greenhouse Gas Emissions: Methods to Support International Climate Agreements, proposed that the US could use the system of existing commercial and civilian satellites to monitor other countries’ emissions and compliance with Kyoto Protocol CO₂ agreements with high precision and accuracy.³⁰ The DoD’s JASON, another government science advisory group, released a 2011 report, Methods for Remote Determination of CO₂ Emissions, that provided a technical explanation of how the emissions monitoring could work.³¹

The 2015 Paris Agreement on Climate Change (Paris Agreement) replaced the Kyoto Protocol with stricter and more deliberate emissions regulations. The Paris Agreement continues to be a critical international joint framework of action. The Obama administration initially joined the Paris Agreement, but the Trump administration rescinded US support. Then, in 2021, the Biden administration designated climate change as a national security priority. President Biden rejoined the Paris Agreement on his first day in office. Demonstrated and sustained commitment to global cooperation and adherence is crucial for progress towards strengthening national security and meeting the objectives of international climate and other environmental agreements.³²

Vital resource scarcity and international cooperation

In 2013, the NRC commissioned an independent study and published the report Climate and Social Stress, which linked various climate change risks with threats to human security. Climate change is inextricably linked to modern environmental security.³³ The US Army Environmental Policy Institute defined environmental security as ‘the state of protection of vital interests of the individual, society, [and] natural environment, from threats resulting from anthropogenic and natural impacts on the environment.’³⁴ An inherent characteristic of environmental security is critical resource limitation, which can be an important security factor in conflict.³⁵

Security factors are considered when evaluating the societal stress of climate change, as well as its impact on human populations. These factors, including migration, health and natural resources, and political instability, can threaten national and international security.³⁶ A lack of security exacerbates effects of climate change on global populations.

Global water resources are critical to environmental and international security. Water is a natural compound for which there is no substitute. Lack of water, or decreasing water flow, can heighten or spark conflicts of ‘ownership’ of water resources.³⁷ The indispensability of fresh water can be the source of conflict or cooperation along transboundary waterbodies, but water conflicts rarely escalate to reciprocal violent force.³⁸ Global populations depend upon reliable sources of clean fresh water as a building block of society and survival, thus increasing water scarcity is an emerging threat that cannot be ignored. Early efforts by MEDEA to use satellite imagery and remote sensing for environmental measurement provided a framework for modern studies on freshwater availability limitations.³⁹ The Climate and Social Stress report suggested that arid and drought-prone regions are becoming increasingly water-scarce with climate change, posing a threat to international security.⁴⁰

Changes in climate and subsequent weather-related droughts have led to decreases in food production and concerns for global food security. The IC has analyzed environmental and food security data for decades. The CIA’s 1974 report Potential Implications of Trends in World Population, Food Production, and Climate predicted a lack of ‘normal’ weather patterns induced by climate change-related changes in temperature and precipitation, suggesting that these weather pattern shifts would reduce effectiveness of existing agricultural systems and lead to crop shortages. The report proposed that fertilizer and pesticide applications used to boost agricultural production may decrease crop quality and run off into the drinking water supply, threatening the population with water insecurity.⁴¹ Agricultural runoff promotes eutrophication, a condition of freshwater nutrient overload that causes excessive plant and algal growth and reduces water quality. In a now-declassified secret 1985 report on Soviet food security, the CIA expected ‘temperatures to continue to rise in the grain area because of worldwide increases in atmospheric carbon dioxide.’⁴² The report noted concerns over reduction in food production and emphasized that chemical agricultural additives can improve food security via higher crop yields but also adversely affect crops’ nutritional value and the potability of water supplies.⁴³

Lack of dependable water resources can also affect long-term food security. In the 1970s, Cambodia’s Khmer Rouge reinstated Angkor Empire-era irrigation systems to combat extreme weather cycles of drought and flooding. Poorly designed and managed, the large-scale 1970s irrigation schemes subsequently failed, adding to the existing insufficient agricultural output and widespread famine in that nation.⁴⁴ As described in the CIA’s 1980 report Bleak Prospects for Meeting Kampuchean Food Needs, these inadequate rice harvests – combined with hard labor, lack of medical care, and the regime’s oppressive measures – resulted in the deaths of 10–20% of the country’s population, or two million people, between 1975 and 1979.⁴⁵ Most of the hard labor involved the construction of the irrigation schemes, which the Khmer Rouge believed would increase agricultural productivity and subsequently strengthen the country’s weak economy.⁴⁶ Decades after its 1970s famines, Cambodia remains one of the world’s most food-insecure countries. With recent historic droughts, rain-dependent rice paddies yield insufficient crops, resulting in a situation of food insecurity and economic loss.⁴⁷

Elevated by increasing droughts, food insecurity directly affects human health, often with substantial security implications.⁴⁸ MEDEA contributed to a series of US National Intelligence Council (NIC) reports on the impact of climate change in different regions of the world through 2030. According to the 2009 NIC report China: Impact of Climate Change to 2030, China was at risk of a severe crop shortage and potentially needed substantial imports of food to sustain its population. Chinese experts warned that if negative impacts of climate change were not adequately controlled, crop production could be reduced 37% by the late 21^st century.⁴⁹ The study found China had not effectively developed its farmland,⁵⁰ although water scarcity was likely a major factor limiting crop yields.⁵¹ Recent studies suggest China’s future dependence on domestic agriculture will be much greater than that of the global food market owing to government prioritization of agriculture and strategic food importation.⁵² China’s intensification of agriculture to feed its growing populations has contaminated its drinking water resources through eutrophication. Lake Taihu, China’s third-largest freshwater lake, currently experiences accelerated eutrophication resulting in toxic harmful algal blooms, or HABs, in a critical drinking water source for more than 40 million people in the surrounding area.⁵³

Climate change hazards amplify risks and stress on populations, affecting public health and safety during extreme climatic events such as tropical cyclones, along with pandemics and other disease events.⁵⁴ The CIA-funded 2012 report Climate Extremes: Recent Trends with Implications for National Security predicted the frequency and intensity of extreme weather events will increase vector- and non-vector-borne diseases.⁵⁵ Models tracking the range expansion of malaria, dengue fever, and West Nile virus now incorporate satellite remote-sensing data.⁵⁶ Beyond the tropics, rising temperatures stimulate disease range expansion.⁵⁷ Catalyzed by global warming, thawing of the Arctic permafrost exposes ancient viruses with no prior exposure to humans.⁵⁸

The IC considers biological security risks like pandemics to be magnifiers of threats. The pandemic has raised geopolitical tensions as some governments, such as China and Russia, use vaccine supplies as a source of influence over developing nations.⁵⁹ The synergism of multiple threats can greatly increase the dangers to human populations. For example, warming waters and eutrophication correlate with increased risk of cholera.⁶⁰ The juxtaposition of the intense 2020 Atlantic hurricane season and the COVID-19 pandemic complicated storm evacuations and emergency sheltering, as well as testing and medical resource availability for the virus.⁶¹

In addition, the role of melting glaciers in escalating conflict over global water availability is of strategic importance to government leadership. MEDEA scientists advised on geophysical processes of glaciers and how they have affected melting rates, as well as how glacial melting could affect transboundary conflict. Millions of people in multiple Asian countries rely on Himalayan glaciers as their water source. The 2012 NRC report Himalayan Glaciers: Climate Change, Water Resources, and Water Security explored the security dynamics of melting glacial water sources shared by large populations in adjacent countries.⁶² Accelerating glacial melt in the Hindu Kush-Himalaya mountains leads to ownership disputes and transboundary conflict over diminishing water resources. India and Pakistan rely upon Kashmir’s Siachen Glacier as a critical water source and separately lay claim to a shared glacial river.⁶³ The glacier has a permanent and tense military presence as both countries claim control of the city of Kashmir and have a nuclear arsenal. Supporting highly populous countries, substantially reduced Himalayan glacial river flows could result in mass population displacement.⁶⁴ The shrinking of the Indus River and its tributary Kabul River further intensifies a historical transboundary conflict in the Kabul River Basin between Afghanistan and Pakistan as each country claims absolute sovereignty over the water source.⁶⁵ Tibetan glacial and snow melt is the source of ten major river systems, including the Yangtze and Mekong, flowing into China and nine other countries. Conflicts over government control between China and Tibet stem from China’s desire to control the water supply.⁶⁶

MEDEA anticipated that reduced water availability would lead to numerous environmental security issues including transboundary violent conflict and population displacement.⁶⁷ GFP-declassified reconnaissance satellite imagery and modern stereo satellite imagery show that, on average, Himalayan glaciers melted twice as rapidly from 2000–2016 as they did from 1975–2000.⁶⁸ Heavily-populated regions of Asia depend on glacial meltwater,⁶⁹ so an accelerating decline in the freshwater source could be disastrous for populations unable to adapt or migrate. As water resources diminish, sustained monitoring and analysis by science advisory groups can identify environmental security concerns and anticipate fragile and water-scarce regions in preparation for non-diplomatic escalation.

Military implications of data-driven climate security

The Arctic region was a key domain of MEDEA’s research and activity. In an effort to map Arctic sea ice thickness, MEDEA collaborated with the IC and the US Navy to analyze distance measurements between submarines, sea ice, and satellites. In addition to providing scientifically and strategically valuable insight into the pattern and extent of Arctic sea ice melt, these measurements allowed the Navy to better determine where its submarines could launch missiles through the ice.⁷⁰ From 1995–1997, MEDEA worked with the US Navy and its Navy Environmental Task Force (Navy ETF). The Navy had collected more than 100 ship-years of oceanographic data of value to climate change research efforts. In June 1995, MEDEA published Scientific Utility of Naval Environmental Data: A MEDEA Special Task Force Report on key Navy ETF findings and recommendations.⁷¹ The collaboration between the Navy and MEDEA resulted in the public release of the largest dataset synthesized into a single coherent database of six million in situ oceanographic observations, vastly expanding the amount of oceanographic data publicly available for scientific research.⁷²

Well-documented longitudinal research by MEDEA scientists linked anthropogenic climate change to accelerating melting rates of Arctic sea ice.⁷³ With decreasing sea ice leading interest in circumpolar trade and expanded icebreaker fleets, the Arctic is emerging as a major economic and national security frontier. A more open Arctic Sea will allow for new shipping routes, a potential source of international conflict. Long-term Arctic hydrocarbon resource reserves have immense economic potential, while near-term economic drivers in the Arctic are more likely to be stimulated by access to deep-sea mining reserves of rare-Earth and strategic minerals.⁷⁴

More notably, navies from Arctic and near-Arctic nations will soon be able to traverse the Arctic Sea more efficiently, turning the region into a geostrategic or geopolitical arena.⁷⁵ According to the US Navy Task Force Climate Change’s report U.S. Navy Arctic Roadmap 2014–2030, the US Arctic national security strategy is to safeguard and protect the US and its interests.⁷⁶ Despite the US’s overwhelming global superiority in military spending, the Russian Navy currently has more icebreaker vessels than the combined Arctic icebreaker fleets of both the US and European countries.⁷⁷ With the potential for future military conflict and geopolitics yet to be settled, national security issues related to the warming Arctic Sea emphasize the growing importance of the focus on environmental security at military frontiers.

In 1995, Vice President Gore worked with Russian Prime Minister Victor Chernomyrdin to initiate a cooperative diplomatic effort that became known as the US-Russian Joint Commission on Economic and Technological Cooperation, or the Gore-Chernomyrdin Commission. Both the US and Russia wanted to advance their energy, space, science, and technology agendas, so the Commission was diplomatically strategic as one of the first major collaborations between US and Russian scientists after the end of the Cold War. The international, interdisciplinary approach to produce a fruitful dialogue between both parties, serving different interests but seeking a common goal, constituted an opportunity for science diplomacy and facilitated greater cooperation and an unprecedented exchange of scientific information.⁷⁸

MEDEA supported these US diplomatic efforts through scientific collaboration, bringing a delegation of MEDEA members to work with an analogous group of oceanographers and other scientists in Russia. In a bilateral exchange, the US and Russia shared satellite imagery taken over each other’s country during the Cold War, providing both with historical records of geographic changes going back to the 1960s.⁷⁹ The Commission also created a combined dataset of existing measurements from US and Soviet submarines and Arctic climatological records to mutually monitor global climate change.⁸⁰ Owing to the customarily adversarial nature of the relationship between the two countries, this diplomatic ‘enterprise of cooperation’ had been impossible during the Cold War; in recent years such an endeavor has become implausible.⁸¹

Russia and the US signed agreements to combine Russian and American intelligence as part of the effort for the cooperative collection of climatic data via ocean temperature and information technology, as well as the consultation over the mitigation of hazardous contaminant levels in the Arctic Sea. In one collaborative effort, MEDEA scientists worked with Russian counterparts to assess the 1949–1956 Russian Techa River dumping of 2.75 million curies of liquid radioactive waste that had migrated to the Arctic Sea from the Chelyabinsk-65 nuclear facility (also known as Mayak).⁸² The American and Russian scientists used Russian oceanographic data to determine the distribution of the radioactive material in the Arctic and potential effects on North American waters.⁸³

During the Cold War, US and Soviet armed forces produced enormous amounts of hazardous military wastes.⁸⁴ The Soviet Union, the United States, and other countries disposed of much of their Second World War munitions by simply dumping them into the ocean.⁸⁵ Governments deemed dumping chemical munitions in the oceans as safe, since ocean currents theoretically would disperse and dilute the chemicals over time. Conversely, scientists advocated for a ban on ocean dumping of chemical weapons.⁸⁶ In 1997, MEDEA published the report Ocean Dumping of Chemical Munitions: Environmental Effects in Arctic Seas. One of the first scientific investigations into marine munitions dumping, the report detailed the dispersal and toxicity of Soviet Cold War chemical warfare munitions, such as sarin and mustard gas, dumped into the Arctic. These inquiries probed into the ecological and health effects as well.⁸⁷

Nuclear testing and nuclear waste dumping are contentious diplomatic matters, with parties disagreeing over allowable actions and liable countries blaming others for dumping malpractices. Fifty or more nuclear warheads and eleven nuclear reactors litter the ocean floor from naval accidents.⁸⁸ More nuclear reactors are located at sea than on land, and the clean-up of military-related sites is estimated to cost more than US$500 billion.⁸⁹ Nuclear warheads launched into the ocean have substantial and extended effects on humans and the environment. While international agreements now prohibit nuclear testing, the increasing prevalence of nuclear power around the world adds to the concern of radioactive environmental contamination, as suitable nuclear waste sites are limited.

MEDEA investigated environmental factors affecting different regions of the globe where the US military carries out operations. The DoD’s 2014 Climate Change Adaptation Roadmap begins: ‘Climate change will affect the Department of Defense’s ability to defend the Nation and poses immediate risks to US national security.’⁹⁰ Climate change can exacerbate threats faced by the United States, including terrorism as well as reduced access to quality land, agricultural resources, and water supply.⁹¹ When natural resources necessary for survival and health are at risk, the chances for societal discontent and potential uprisings grow.

Conditions and instability intensified by climate change can exacerbate or spark conflict and increase regional and national security concerns. As the IC became more acutely aware of the national security implications of climate change, it requested MEDEA’s expertise in predicting when and where climate change implications might be realized globally.⁹² MEDEA’s scientific progress and methodological development helped the US military more accurately forecast, plan, and act on negative security effects posed by climate change.⁹³ The military considers climate change to be a threat multiplier, which refers to climate change’s tendency to accelerate instability resulting from the diminished availability of natural resources.⁹⁴ The military is better equipped to respond to conflicts when it understands the progression of global and regional environmental changes.

Conflict involving violent non-state actors intensifies with water scarcity and results in schemes to control natural resources. When the Islamic State in Iraq and Syria (ISIS) took over land in Syria and Iraq during extreme regional drought in 2014, ISIS captured much of the public infrastructure in the Iraqi city of Mosul. This infrastructure provided surrounding villages with water supply, which the group temporarily cut off as a coercive tactic to force compliance to ISIS demands. In Somalia, Al-Shabaab has targeted the country’s water infrastructure and sources multiple times during the country’s ongoing civil war. Boko Haram exploits water stress in Nigeria to create destabilization and gain power.⁹⁵ Internal conflicts can become regionally or even internationally destabilizing; thus, increasing water scarcity has the potential to create instability across broader regions of the globe.

Drought, extreme weather events, and subsequent population displacement are national security issues,⁹⁶ and environmental monitoring of particular regions over time highlights potential areas of political destabilization. When climate change-augmented drought parched the crops of rural Syrian farmers, the resulting risk of famine forced approximately 1.5 million Syrians into the country’s cities, putting pressure on the infrastructure and government. The instability caused by the enormous population influx was a major contributor to the start of the Syrian Civil War. Increases in global food prices followed with less grains available on the global market, consequently leading to widespread food shortages.⁹⁷

MEDEA’s report Environment and National Security: Key Issues for the New Administration reinforced the importance of science advisers for informed climate-related decision-making. Importantly, the report established the need to conduct climate change research and monitoring to address environmental security, military preparedness, and diplomacy. Following the report’s release in 2000, MEDEA’s work was paused in 2001 until Congress revived the program from 2007–2015 with a greater emphasis on national security. The 2019 Congressional War and National Defense Authorization Act mandated the creation within the IC of a Climate Security Advisory Council (CSAC), followed by the establishment of a National Academies Climate Security Roundtable of climate science stakeholders the following year. The CSAC was assigned a role with responsibilities similar to MEDEA, including the option of pursuing a dialogue or relationship with scientists and other experts outside the IC.⁹⁸ Upon entering office in January 2021, President Biden implemented a Presidential Task Force on Climate Change to advise on the administration’s climate efforts. An early e.o. by President Biden required the preparation of the NIE referred to at the beginning of this article, entitled Climate Change and International Responses Increasing Challenges to US National Security Through 2040.⁹⁹ The IC tasked the CSAC with reviewing the scientific content of the report.

Conclusion

Science advisory groups can assist the IC in supporting the executive branch’s environmental security and science diplomacy initiatives. Collective research and predictive analysis by groups such as MEDEA can guide intelligence planning and development. Administrations should embrace science diplomacy partnerships, including those enhanced by IC-scientific community collaboration like the Gore-Chernomyrdin Commission. Countries have the opportunity to build stronger relationships with their allies and partner with rival countries through combined efforts to combat climate change risks and improve security resilience. The relationship between the IC and the scientific community in the United States can help to address issues of diplomacy and defense policy through shared resources and methods.

The MEDEA program highlighted the need for more accurate climate change monitoring metrics, laying out an innovative approach that can lead to improved international agreements that address global environmental challenges. This scientific advisement on the Paris Climate Agreement and other UNFCCC international agreements provides an opportunity for greater oversight and cooperation among participating countries. Security-informed global collaboration and monitoring are necessary to reduce the probability of the worst effects of climate change, and a dedicated IC-linked science advisory group can help provide the necessary guidance.

Climate change is a rising security threat; hence, the need is pressing for creative efforts to address global climate change and climate security. Throughout the 21^st century, the societal and security implications of climate change will continue to proliferate, with direct and indirect climate change effects exacerbating current conditions. Data collection and interpretation by science advisory groups can advance useful, evidence-based recommendations on matters of national security that stem from a deteriorating global environment. Joint efforts by the intelligence and scientific communities warrant continued support to enable administrations to better answer critical questions of national and human security as they pertain to the changing environment and the need for global cooperation to address the future of the planet.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Evan Barnard

Evan Barnard is a graduate student (Masters) at the School of International Service at American University and the Department of Environment and Development at the United Nations’ University for Peace. He studies climate security and the nexus of anthropogenic environmental change and human society. He studied international affairs and ecology as a Bernard Ramsey Honors Scholar and Honors International Scholar at the University of Georgia. His research focuses on modern environmental security intelligence risks and their basis in the historical development of climate change inquiry and understanding.

Loch K. Johnson

Loch K. Johnson is Regents Professor Emeritus of International Affairs at the University of Georgia. He is the author of over 200 articles and thirty books on U.S. national security, including Spy Watching: Intelligence Accountability in the United States (2018) and National Security Intelligence, 2d ed. (2017). Professor Johnson has been a Congressional Fellow, a Phi Beta Kappa Visiting Scholar, and Distinguished Visiting Scholar at Yale University and Oxford University. In 2012, the Southeastern Conference selected him as its inaugural ‘Professor of the Year’; and, in 2014, the Intelligence Studies Section of the International Studies Association named him a ‘Distinguished Scholar.’ At the University of Georgia, he led the founding of School of Public and International Affairs (SPIA).

James Porter

James Porter is the Josiah Meigs Distinguished Professor of Ecology, Emeritus at the University of Georgia. He has authored three books and published more than 120 articles in academic journals such as Science, Nature, and the Proceedings of the National Academy of Science. His research interests span population and disease ecology, ecology of coral reefs, global climate change, and the ecosystem and human health consequences of underwater munitions. He has testified before US Congress multiple times, including regarding munitions contamination on Puerto Rican coral reefs. His current research focuses on coral health and disease.

Notes

¹ MEDEA, Environment and National Security: Key Issues for the New Administration (December 2000).

² President’s Science Advisory Committee, Restoring the Quality of Our Environment (Washington, DC: The White House, 1965).

³ Office of the Director of National Intelligence, National Intelligence Estimate: Climate Change and International Responses Increasing Challenges to US National Security through 2040 (2021).

⁴ Loch K. Johnson, “The Greening of Intelligence,” in Bombs, Bugs, Drugs, and Thugs: Intelligence and America’s Quest for Security (New York: New York University Press, 2000), 50-71.

⁵ D. James Baker (Former Administrator of NOAA and MEDEA Member), interview by Evan Barnard, 14 November 2018, Washington, DC.

⁶ D. James Baker and Linda Zall, “The MEDEA Program: Opening a Window into New Earth Science Data,” Oceanography 33, no. 1 (2020).

⁷ William Schlesinger (President Emeritus of the Cary Institute of Ecosystem Studies and MEDEA Member), interview by Evan Barnard, 16 April 2018, telephone.

⁸ John A. Orcutt (Distinguished Professor of Geophysics at the Scripps Institution of Oceanography at the University of California at San Diego and MEDEA Member), interview by Evan Barnard, 30 October 2018, telephone.

⁹ Linda Zall (Central Intelligence Agency (ret.) and Former Director of the MEDEA Program), interview by Evan Barnard, 28 October 2018, telephone.

¹⁰ Robert Bindschadler (NASA Emeritus Scientist and MEDEA Member), interview by Evan Barnard, 13 November 2018, telephone.

¹¹ Anthony Janetos (Director of the Frederick S. Pardee Center for the Study of the Longer-Range Future at Boston University and MEDEA Member), interview by Evan Barnard, 30 November 2018, telephone.

¹² Thomas B. Mccord, John Morris, David Persing, Edward Tagliaferri, Cliff Jacobs, Richard Spalding, Louann Grady and Ronald Schmidt, “Detection of a Meteoroid Entry into the Earth’s Atmosphere on 1 February 1994,” Journal of Geophysical Research 100, no. E2 (1995).

¹³ Thomas McCord (Director and Senior Scientist at the Bear Fight Institute, Former NASA Scientist, and MEDEA Member), interview by Evan Barnard, 30 November 2018, telephone.

¹⁴ William H. Schlesinger and Nicholas Gramenopoulos, “Archival Photographs Show No Climate-Induced Changes in Woody Vegetation in the Sudan, 1943-1994,” Global Change Biology 2, no. 2 (1996); F. Fetterer and Norbert Untersteiner, “Melt Pond Coverage Statistics from Classified Satellite Data,” (IEEE, 1998).

¹⁵ National Reconnaissance Office, “President orders declassification of historic satellite imagery citing value of photography to environmental science,” 24 February 1995.

¹⁶ National Research Council, Scientific Value of Arctic Sea Ice Imagery Derived Products (Washington, DC: 2009).

¹⁷ Paul Berkman, “Evolution of Science Diplomacy and Its Local-Global Applications,” European Foreign Affairs Review 24 (2019).

¹⁸ Scott Pace, Kevin M. O’Connell and Beth E. Lachman, Using Intelligence Data for Environmental Needs: Balancing National Interests (Washington, DC: Rand Corporation, 1997).

¹⁹ Robert Bindschadler and Patricia Vornberger, “Changes in the West Antarctic Ice Sheet Since 1963 from Declassified Satellite Photography,” Science 279, no. 5351 (1998).

²⁰ John T. Connor, Memorandum for the President: The Weather Services of the Environmental Science Services Administration, (Washington DC: 13 September 1965).

²¹ Michael Matson and Jeff Dozier, “Identification of Subresolution High Temperature Sources Using a Thermal IR Sensor,” Photogrammetric Engineering and Remote Sensing 47, no. 9 (1981).

²² Rick Spinrad (NOAA Administrator and MEDEA Member), interview by Evan Barnard, 29 October 2018, telephone.

²³ John Deutch, “The Environment on the Intelligence Agenda” (lecture, World Affairs Council, Los Angeles, CA, 25 July 1996).

²⁴ A. Park Williams, John T. Abatzoglou, Alexander Gershunov, Janin Guzman-Morales, Daniel A. Bishop, Jennifer K. Balch and Denis P. Lettenmaier, “Observed Impacts of Anthropogenic Climate Change on Wildfire in California,” Earth’s Future 7(2019).

²⁵ “The Complexities of Wildfires,” Nature Geosciences 12(2019).

²⁶ Matt McDonald, “After the Fires? Climate Change and Security in Australia,” Australian Journal of Political Science (2020).

²⁷ Josh Blumenfeld, “Wildfires Can’t Hide from Earth Observing Satellites,” EarthData, https://Earthdata.nasa.gov/learn/articles/feature-articles/wildfire-articles/wildfires-cant-hide-from-Earth-observing-satellites.

²⁸ Jeff Dozier (Distinguished Professor Emeritus at the University of California at Santa Barbara and MEDEA Member), interview by Evan Barnard, 8 January 2019, Skype.

²⁹ National Research Council, Monitoring Climate Change Impacts: Metrics at the Intersection of the Human and Earth Systems (Washington, DC: 2010).

³⁰ National Research Council, Verifying Greenhouse Gas Emissions: Methods to Support International Climate Agreements (Washington, DC: National Research Council, 2010).

³¹ JASON, Methods for Remote Determination of CO₂ Emissions (McLean, VA: MITRE Corporation, 2011).

³² Climate Security Advisory Group, A Climate Security Plan for America: A Presidential Plan for Combatting the Security Risks of Climate Change (Center for Climate and Security, September 2019).

³³ National Research Council, Climate and Social Stress: Implications for Security Analysis (Washington, DC: National Academies, 2013).

³⁴ Jerome C. Glenn, Theodore J. Gordon and Renat Perelet, Defining Environmental Security: Implications for the U.S. Army (Army Environmental Policy Institute, 1998).

³⁵ Thomas F. Homer-Dixon, “On the Threshold: Environmental Changes as Causes of Acute Conflict,” International Security 16, no. 2 (1991); Thomas F. Homer-Dixon, “Environmental Scarcities and Violent Conflict: Evidence from Cases,” International Security 19, no. 1 (1994).

³⁶ National Research Council, Climate and Social Stress.

³⁷ Ibid.

³⁸ Aaron T. Wolf, “Conflict and Cooperation along International Waterways,” Water Policy 1(1998); Hussam Hussein, “Politics of the Dead Sea Canal: a Historical Review of the Evolving Discourses, Interests, and Plans,” Water International 42, no. 5 (2017).

³⁹ Megan M. Coffer, Blake A. Schaeffer, John A. Darling, Erin A. Urquhart and Wilson B. A. Saals, “Quantifying National and Regional Cyanobacterial Occurrence in US Lakes Using Satellite Remote Sensing,” Ecological Indicators 111(2020); Birgit Heim, Hedi Oberhaensli, Susanne Fietz and Hermann Kaufmann, “Variation in Lake Bikal’s Phytoplankton Distribution and Fluvial Input Assessed by Sea WiFS Satellite Data,” Global and Planetary Change 46(2005).

⁴⁰ National Research Council, Climate and Social Stress.

⁴¹ Office of Political Research, Potential Implications of Trends in World Population, Food Production, and Climate (Directorate of Intelligence, Central Intelligence Agency, 1974).

⁴² Directorate of Intelligence, Soviet Climate Change: Implications for Grain Production (Central Intelligence Agency, 1985).

⁴³ Ibid.

⁴⁴ Mak Sithirith, “Water Governance in Cambodia: From Centralized Water Governance to Farmer Water User Community,” Resources 6, no. 44 (2017).

⁴⁵ National Foreign Assessment Center, Bleak Prospects for Meeting Kampuchean Food Needs (Central Intelligence Agency, 1980); Randle C. DeFalco, “Justice and Starvation in Cambodia: The Khmer Rouge Famine,” Cambodia Law & Policy Journal 45, no. 2 (2014).

⁴⁶ Corrine Coakley, Mandy Munro-Stasiuk, Sokvisal Kimsroy, Chhunly Chhay and Stian Rice, “Extracting Khmer Rouge Irrigation Networks from pre-Landsat 4 Satellite Imagery Using Vegetation Indices,” Royal Geographic Society 52, no. 2 (2019); Stian Rice, James Tyner, Mandy Munro‐Stasiuk, Sokvisal Kimsroy and Corrine Coakley, “The hydro‐logic of genocide: Remaking land, water, and bodies in democratic Kampuchea, 1975–1979,” Area 52, no. 2 (2020).

⁴⁷ Nyda Chhinh, Hoeurn Cheb and Naret Heng, “Drought Risk in Cambodia: Assessing Costs and a Potential Solution,” Asian Journal of Agriculture and Development 11, no. 2 (2014); Subir Bairagi, Ashok K. Mishra and Alvaro Durand-Morat, “Climate risk management strategies and food security: Evidence from Cambodian rice farmers,” Food Policy 95(2020).

⁴⁸ Center for Strategic and International Studies, Climate Change and Food Security: A Test of U.S. Leadership in a Fragile World (Washington, DC: Center for Strategic and International Studies, 2019).

⁴⁹ National Intelligence Council, China: Impact of Climate Change to 2030: A Commissioned Report (2009).

⁵⁰ Ibid.

⁵¹ Richard P. Thomas, Stephen H. Conrad, David M. Jeppesen and Dennis Engi, Understanding the Dynamics of Water Availability and Use in China (Sandia National Laboratories, 1997); Stephen H. Conrad, Thomas E. Drennen, Dennis Engi, David L Harris, David M. Jeppesen and Richard P. Thomas, Modeling the Infrastructure Dynamics of China: Water, Agriculture, Energy, and Greenhouse Gases (Sandia National Laboratories, 1998).

⁵² Xing Wei, Zhao Zhang, Peijun Shi, Pin Wang, Yi Chen, Xiao Song and Fulu Tao, “Is Yield Increase Sufficient to Achieve Food Security in China?” PLoS ONE 14, no. 8 (2015).

⁵³ Boqiang Qin, Hans W. Paerl, Justin D. Brookes, Jianguo Liu, Erik Jeppesen, Guangwei Zhu, Yunlin Zhang, Hai Xu, Kun Shi and Jianming Deng, “Why Lake Taihu Continues to Be Plagued with Cyanobacterial Blooms Through 10 Years (2007–2017) Efforts,” Science Bulletin 64, no. 6 (2019).

⁵⁴ Carly A. Phillips, Astrid Caldas, Rachel Cleetus, Kristina A. Dahl, Juan Declet-Barreto, Rachel Licker, L. Delta Merner, J. Pablo Ortiz-Partida, Alexandra L. Phelan, Erika Spanger-Siegfried, Shuchi Talati, Christopher H. Trisos and Colin J. Carlson, “Compound Climate Risks in the COVID-19 Pandemic,” Nature Climate Change 10(2020).

⁵⁵ Michael McElroy and D. James Baker, Climate Extremes: Recent Trends with Implications for National Security (2012).

⁵⁶ Elisavet Parselia, Charalampos Kontoes, Alexia Tsouni, Christos Hadjichristodoulou, Ioannis Kioutsioukis, Gkikas Magiorkinis and Nikolaos I. Stilianakis, “Satellite Earth Observation Data in Epidemiological Modeling of Malaria, Dengue and West Nile Virus: A Scoping Review,” Remote Sensing 11, no. 16 (2019).

⁵⁷ Institute of Medicine, Global Climate Change and Extreme Weather Events: Understanding the Contributions to Infectious Disease Emergence (Washington, DC: National Academy Press, 2008).

⁵⁸ Joshua J. Steffan, Jade A. Derby and Eric C. Brevik, “Soil Pathogens that May Potentially Cause Pandemics, Including SARS Coronaviruses,” Current Opinion in Environmental Science & Health (2020).

⁵⁹ Office of the Director of Central Intelligence, National Intelligence Estimate: The Global Infectious Disease Threat and Its Implications for the United States (2000); Office of the Director of National Intelligence, Annual Threat Assessment of the US Intelligence Community (2021).

⁶⁰ Paul R. Epstein, “Cholera and the Environment: An Introduction to Climate Change,” The PSR Quarterly 2, no. 3 (1992); Sara L. M. Trærup, Ramon A. Ortiz and Anil Markandya, “The Costs of Climate Change: A Study of Cholera in Tanzania,” International Journal of Environmental Research and Public Health 8, no. 12 (2011).

⁶¹ James M. Shultz, James P. Kossin, Attila Hertelendy, Fredrick Burkle, Craig Fugate, Ronald Sherman, Johnna Bakalar, Kim Berg, Alessandra Maggioni, Zelde Espinel, Duane E. Sands, Regina C. Larocque, Renee N. Salas and Sandro Galea, “Mitigating the Twin Threats of Climate-Driven Atlantic Hurricanes and COVID-19 Transmission,” Disaster Medicine and Public Health Preparedness 14, no. 4 (2020).

⁶² National Research Council, Himalayan Glaciers: Climate Change, Water Resources, and Water Security (Washington, DC: National Research Council, 2012).

⁶³ Ibid.

⁶⁴ Bruce Molnia (Senior Science Advisor for National Civil Applications at USGS and MEDEA Member), interview by Evan Barnard, 19 November 2018, telephone.

⁶⁵ Shakib Atef, Fahima Sadeqinazhad, Faisal Farjaad and M. Amatya, “Water conflict management and cooperation between Afghanistan and Pakistan,” Journal of Hydrology 570(2019).

⁶⁶ Dechen Palmo, “Tibet”s Rivers Will Determine Asia’s Future,” The Diplomat, 1 November 2019, https://thediplomat.com/2019/11/tibets-rivers-will-determine-asias-future/.

⁶⁷ Richard Matthew, “Climate Change and Water Security in the Himalayan Region,” Asia Policy 16(2013).

⁶⁸ J. M. Maurer, J. M.Schaefer, S. Rupper and A. Corley, “Acceleration of Ice Loss Across the Himalayas over the Past 40 Years,” Science Advances 5, no. 6 (2019).

⁶⁹ National Research Council, Himalayan Glaciers.

⁷⁰ Spinrad, interview.

⁷¹ MEDEA, Scientific Utility of Naval Environmental Data: A MEDEA Special Task Force Report (MEDEA, 1995).

⁷² Baker and Zall, “The Medea Program.”

⁷³ National Research Council, Sea Ice Imagery.

⁷⁴ Navy Task Force Climate Change, The United States Navy Arctic Roadmap for 2014 to 2030 (United States Navy Chief of Naval Operations, 2014).

⁷⁵ National Research Council, National Security Implications of Climate Change for U.S. Naval Forces (Washington, DC: 2011).

⁷⁶ Navy Task Force Climate Change, Navy Arctic Roadmap.

⁷⁷ USCG Office of Waterways and Ocean Policy, Major Icebreakers of the World, (United States Coast Guard, 2017).

⁷⁸ Paul Berkman, “Science Diplomacy and Its Engine of Informed Decisionmaking: Operating through Our Global Pandemic with Humanity,” The Hague Journal of Diplomacy 15, no. 3 (2020).

⁷⁹ Jeffrey T. Richelson, “Scientists in Black,” Scientific American 278, no. 2 (1998).

⁸⁰ Michael Carlowicz, “New Data from Cold War Treasure Trove,” Eos 78, no. 9 (1997); Paul Gaffney (Vice Admiral (ret), President Emeritus of Monmouth University, and MEDEA Member), interview by Evan Barnard, 11 December 2018, telephone.

⁸¹ Robert Corell (Former Assistant Director of the National Science Foundation for Geoscience and MEDEA Member), interview by Evan Barnard, 11 December 2018, telephone.

⁸² GlobalSecurity.org, “Chelyabinsk-65,” https://www.globalsecurity.org/wmd/world/chelya/chelyabinsk-65_nuc.htm.

⁸³ Deutch, “Intelligence Agenda.”

⁸⁴ David Hay-Edie, The Military’s Impact on the Environment: A Neglected Aspect of the Sustainable Development Debate (Geneva: International Peace Bureau, 2002).

⁸⁵ Orcutt, interview.

⁸⁶ Tobias Knobloch, Jacek Beldowski, Claus Böttcher, Martin Söderström, Niels-Peter Rühl and Jens Sternheim, Chemical Munitions Dumped in the Baltic Sea: Report of the ad hoc Expert Group to Update the Existing Information on Dumped Chemical Munitions in the Baltic Sea (HELCOM, 2013).

⁸⁷ MEDEA, Ocean Dumping of Chemical Munitions: Environmental Effects in Arctic Seas (MEDEA, 1997).

⁸⁸ Jacob Darwin Hamblin, “Environmental Diplomacy in the Cold War: The Disposal of Radioactive Waste at Sea during the 1960s,” The International History Review 24, no. 2 (2002).

⁸⁹ Ibid.

⁹⁰ Department of Defense, 2014 Climate Change Adaptation Roadmap (2014).

⁹¹ National Research Council, Climate and Social Stress.

⁹² Zall, interview.

⁹³ National Research Council, Climate and Social Stress.

⁹⁴ CNA Military Advisory Board, National Security and the Threat of Climate Change (Alexandria, VA: CNA Corporation, 2007).

⁹⁵ CNA Military Advisory Board, National Security and the Accelerating Risks of Climate Change (Alexandria, VA: CNA Corporation, 2014).

⁹⁶ Zall, interview.

⁹⁷ Collin P. Kelley, Shahrzad Mohtadi, Mark A. Cane, Richard Seager and Yochanan Kushnir, “Climate Change in the Fertile Crescent and Implications of the Recent Syrian Drought,” PNAS 112, no. 11 (2015).

⁹⁸ U.S. Congress, “Climate Security Advisory Council,” Sessional Papers, War and National Defense, 19 December 2019, ch. 44.I, sec. 3060.

⁹⁹ Office of the Director of National Intelligence, Climate Change and International Response.