Today, November 23rd, 2018, the Fourth National Climate Assessment Volume II was released. NCA4 Vol II, Impacts, Risks, and Adaptation in the United States, assesses a range of potential climate change-related impacts, with an aim to help decision makers better identify risks that could be avoided or reduced. The assessment follows Vol I, the Climate Science Special Report (CSSR), which was released in November 2017. Together, these reports meet the requirements of the Global Change Research Act, which mandates a quadrennial assessment of our understanding of global change and its impacts on the United States.
The last NCA3 was released in 2014. One of the main “Topics For Consideration In Future Assessments” was “National Security.” As such, there was a significant increase in the coverage of national security matters in this latest National Climate Assessment. This is consistent with assessments coming from both the Department of Defense and the National Intelligence Council during this Administration. Below is a list of only those mentions of climate change impacts on national security and the military in the report that are explicit. The full assessment also covers broader human, food, water, and energy security matters, which can certainly have national security implications, so we encourage readers interested in climate and security to explore the whole report.
National Security in the Fourth National Climate Assessment
The below are direct excerpts from the “Report-in-Brief” and the individual chapters highlighting explicit mentions of climate change impacts on “national security” and the “military.”
3 Interconnected Impacts: Climate change presents added risks to interconnected systems that are already exposed to a range of stressors such as aging and deteriorating infrastructure, land-use changes, and population growth. Extreme weather and climate-related impacts on one system can result in increased risks or failures in other critical systems, including water resources, food production and distribution, energy and transportation, public health, international trade, and national security. The full extent of climate change risks to interconnected systems, many of which span regional and national boundaries, is often greater than the sum of risks to individual sectors. Failure to anticipate interconnected impacts can lead to missed opportunities for effectively managing the risks of climate change and can also lead to management responses that increase risks to other sectors and regions. Joint planning with stakeholders across sectors, regions, and jurisdictions can help identify critical risks arising from interaction among systems ahead of time. (pg 13)”
10 Infrastructure: “Our Nation’s aging and deteriorating infrastructure is further stressed by increases in heavy precipitation events, coastal flooding, heat, wildfires, and other extreme events, as well as changes to average precipitation and temperature. Without adaptation, climate change will continue to degrade infrastructure performance over the rest of the century, with the potential for cascading impacts that threaten our economy, national security, essential services, and health and well-being. (pg 17)”
Human Health and Well-Being “Combined with other stressors, sea level rise, coastal storms, and the deterioration of coral reef and mangrove ecosystems put the longterm habitability of coral atolls in the Hawai‘i and U.S.-Affiliated Pacific Islands region at risk, introducing issues of sovereignty, human and national security, and equity (Ch. 27: Hawai‘i & Pacific Islands, KM 6).(pg 27).”
Box 1.4: How Climate Change Around the World Affects the United States “Natural variability and changes in climate increase risks to our national security by affecting factors that can exacerbate conflict and displacement outside of U.S. borders, such as food and water insecurity and commodity price shocks. More directly, our national security is impacted by damage to U.S. military assets such as roads, runways, and waterfront infrastructure from extreme weather and climate-related events (Figures 1.8 and 1.9). The U.S. military is working to both fully understand these threats and incorporate projected climate changes into long-term planning. For example, the Department of Defense has performed a comprehensive scenario-driven examination of climate risks from sea level rise to all of its coastal military sites, including atolls in the Pacific Ocean (Ch. 16: International, KM 3) (pg 28).”
Mitigation “Recent studies suggest that some of the indirect effects of mitigation actions could significantly reduce—or possibly even completely offset—the potential costs associated with cutting greenhouse gas emissions. Beyond reduction of climate pollutants, there are many benefits, often immediate, associated with greenhouse gas emissions reductions, such as improving air quality and public health, reducing crop damages from ozone, and increasing energy independence and security through increased reliance on domestic sources of energy (Ch. 13: Air Quality, KM 4; Ch. 29: Mitigation, KM 4). (pg31)”
Adaptation “Effective adaptation can also enhance social welfare in many ways that can be difficult to quantify, including improving economic opportunity, health, equity, national security, education, social connectivity, and sense of place, while safeguarding cultural resources and enhancing environmental quality. (pg 32-33).”
What Has Happened Since the Last National Climate Assessment? – New Aspects of This Report – New Chapters: “Public input also requested greater international context in the report, which has been addressed through two new additions. A new chapter focuses on topics including the effects of climate change on U.S. trade and businesses, national security, and U.S. humanitarian assistance and disaster relief (Chapter 16). A new international appendix (Appendix 4) presents a number of illustrative examples of how other countries have conducted national climate assessments, putting our own effort into a global context.”
Chapter 4: Energy Supply, Delivery, and Demand (Full Chapter)
Key Message 1 Nationwide Impacts on Energy: The Nation’s energy system is already affected by extreme weather events, and due to climate change, it is projected to be increasingly threatened by more frequent and longer-lasting power outages affecting critical energy infrastructure and creating fuel availability and demand imbalances. The reliability, security, and resilience of the energy system underpin virtually every sector of the U.S. economy. Cascading impacts on other critical sectors could affect economic and national security. (page 70 Executive Summary)”
State of the Sector: The Nation’s economic security is increasingly dependent on an affordable and reliable supply of energy. Every sector of the economy depends on energy, from manufacturing to agriculture, banking, healthcare, telecommunications, and transportation.2 Increasingly, climate change and extreme weather events are affecting the energy system (including all components related to the production, conversion, delivery, and use of energy), threatening more frequent and longer-lasting power outages and fuel shortages.3 Such events can have cascading impacts on other critical sectors43,44 and potentially affect the Nation’s economic and national security (see Ch. 17: Complex Systems).
Box 4.2: Changing Dimensions of Energy Security: There is a trend of decreasing net imports (imports minus exports) of petroleum. In 2016, U.S. net imports reached a new low equal to about 25% of U.S. petroleum consumption, down from 60% in 2005.59 ,61 This significant decline is the result of several factors, including the exploitation of vast domestic shale oil reserves and, to a lesser extent, reduced demand levels and expanded biofuel production. While this shift has potential national security benefits, there is an accompanying altered geographic distribution of our energy production assets and activities that could result in changes in exposure to the effects of extreme weather and climate change.”
Key Message 3 Improving Energy System Resilience: “The Nation’s economic security is increasingly dependent on an affordable and reliable supply of energy. Every sector of the economy depends on energy, from manufacturing to agriculture, banking, healthcare, telecommunications, and transportation. Increasingly, climate change and extreme weather events are affecting the energy system, threatening more frequent and longer-lasting power outages and fuel shortages. Such events can have cascading impacts on other critical sectors, potentially affecting the Nation’s economic and national security. At the same time, the energy sector is undergoing substantial policy, market, and technology-driven changes that are projected to affect these vulnerabilities. (page 71)”
Chapter 7 Ecosystems, Ecosystem Services, & Biodiversity (Full Chapter)
Ecosystem Services at Risk: “A reduced supply of critical provisioning services (food, fiber, and shelter) has clear consequences for the U.S. economy and national security and could create a number of challenges for natural resource managers.104
Chapter 8 Coastal Effects (Full Chapter)
Case Study: Messages in Action – Norfolk, Virginia: “Low-lying Norfolk—Virginia’s second-largest city—is enduring serious physical, financial, and social impacts as the frequency of high tide flooding accelerates due to rising local sea level.6 High tide flooding threatens access routes, historical neighborhoods, personal and commercial property integrity and value, and national security, given that Norfolk houses the world’s largest naval base. The city has begun to invest in mitigation and adaptation actions,117 but recent estimates indicate it will cost hundreds of millions of dollars to improve storm water pipes, flood walls, tide gates, and pumping stations.118 Natural and nature-based infrastructure projects such as the Colley Bay living shoreline have improved water quality, mitigated erosion, and restored habitats.119 Additional planned projects include constructing berms, reclaiming filled waterways and wetlands, and raising roads and structures. City officials have identified the neighborhoods of The Hague and Pretty Lake as top priorities for flood mitigation, but in other areas of the city where containment will be more difficult, residents face the possibility of abandoning their homes (Figure 8.7).118 ,120… Given that the city is home to Naval Station Norfolk and other national security facilities, the Department of Defense has also contributed to plans for the city’s future (Ch. 1: Overview, Figure 1.8). Naval Station Norfolk supports multiple aircraft carrier groups and is the duty station for thousands of employees.122 Most of the area around the base lies less than 10 feet above sea level,123 and local relative sea level is projected to rise between about 2.5 and 11.5 feet by the year 2100 under the Intermediate-Low global SLR scenario (considered likely under the lower [RCP4.5] and very low [RCP2.6] scenarios) and the Extreme SLR scenario (considered worst case under a higher scenario, RCP8.5 ), respectively.36 The Navy is studying how flooding in Norfolk and Virginia Beach affects military readiness when sailors and other employees who live off-base are unable to reach the naval station for work.124 Ultimately, the lessons learned in Norfolk—both the successes and challenges—are transferable to other coastal communities across the United States and its territories.”
Chapter 14 Human Health (Full Chapter)
Box 14.2 Transboundary Transmission of Infectious Diseases “Outbreaks occurring in other countries can impact U.S. populations and military personnel living abroad and can sometimes affect the United States. For example, the 2015–16 El Niño, one of the strongest on record,44 may have contributed to the 2014–16 Zika epidemic in the Americas.31 ,45 ,46 ,47,48 Warmer conditions may have facilitated expansion of the geographic range of mosquito populations and increased their capacity to transmit Zika virus.40 Zika virus can cause a wide range of symptoms, including fever, rash, and headaches, as well as birth defects. The outbreak began in South America and spread to areas with mosquitoes capable of transmitting the virus, including Puerto Rico, the U.S. Virgin Islands, Florida, and Texas.”
Chapter 16: Climate Effects on U.S. International Interests (Full Chapter)
Introduction The global impacts of climate (climate change, variability, and extreme events) are already having important implications for societies and ecosystems around the world and are projected to continue to do so into the future.1 ,2 ,3 There are specific U.S. interests that can be affected by climate-related impacts outside of U.S. borders, such as climate variability (for example, El Niño/La Niña events), climate extremes (for example, floods resulting from extreme precipitation), and long-term changes (for example, sea level rise). These interests include economics and trade (Key Message 1), international development and humanitarian assistance (Key Message 2), national security (Key Message 3), and transboundary resources (Key Message 4). While these four topics are addressed separately, they can also affect each other. For example, climate-related disasters in developing countries not only have significant local and regional socioeconomic impacts, but they can also set back U.S. development investments, increase the need for U.S. humanitarian assistance, and affect U.S. trade and national security. U.S. citizens have long been concerned about the welfare of those living beyond U.S. borders and their vulnerability to the global impacts of climate.4 ,5
Economics and Trade “In addition to local impacts on U.S.-owned assets abroad, climate change is expected to lead to large-scale shifts in the availability and prices of a wide array of agricultural,12 ,13 energy,14 ,15 and other goods, with corresponding impacts on the U.S. economy. These impacts occur on a wide range of timescales, ranging from months to multiple decades. For example, the prices of agricultural and mining commodities and manufactured goods are affected by year-to-year and decadal climate variations in the availability of irrigation water for agriculture or hydroelectric power.16 ,17 ,18 ,19International price changes affect U.S. businesses abroad, as well as U.S. exports and imports. An example is the damaging effect that a series of short-term climate extremes in 2010 and 2011 had on global wheat production. These extremes included drought in Russia, Ukraine, and the United States and damaging precipitation in Australia. A corresponding reduction in wheat production, in combination with high demand, low stocks, trade policies, and other factors, contributed to a spike in global wheat prices.20 This benefited U.S. wheat exports while increasing the cost of flour and bread in the United States.21 This example highlights the complex interactions that often arise through major impacts of overseas climate change, variability, or extremes on U.S. interests (see Key Message 3 for a discussion of some of the security implications from the 2010–2011 drought).22Where these impacts increase global market prices, U.S. purchasers and consumers tend to be harmed, whereas U.S. producers tend to benefit. The opposite is generally true for impacts that drive prices down.”
International Development and Humanitarian Assistance: “Many developing countries depend heavily on agriculture as a major source of jobs and a large percentage of their gross domestic product (GDP). Drought can have impacts on food production and security at multiple scales. At the national level, the loss of food and income and the need to help farmers through bad years can set back development. At the household level, drought can wipe out crops and financial assets and leave families vulnerable to starvation.”
Key Message 3 Climate and National Security “Climate change, variability, and extreme events, in conjunction with other factors, can exacerbate conflict, which has implications for U.S. national security. Climate impacts already affect U.S. military infrastructure, and the U.S. military is incorporating climate risks in its planning. (pg 107)”
Climate change and extremes increase risks to national security through direct impacts on U.S. military infrastructure and by affecting factors, including food and water availability, that can exacerbate conflict outside U.S. borders.59 ,60 Droughts, floods, storm surges, wildfires, and other extreme events stress nations and people through loss of life, displacement of populations, and impacts on livelihoods.61 ,62 Increases in the frequency and severity of such events, as well as other aspects of climate change, may require a larger military mission focus on climate-sensitive areas such as coasts, drought-prone areas, and the Arctic.60
Climate change is already affecting U.S. Department of Defense (DoD) assets by, among other impacts, damaging roads, runways, and waterfront infrastructure.63 DoD is working to both fully understand these threats and incorporate projected climate changes into long-term planning to reduce risks and minimize impacts. There are many examples of DoD’s planning and action for risks to its assets from climate change. DoD has performed a comprehensive scenario-driven examination of climate risks from sea level rise to all of its coastal military sites,64 including atolls in the Pacific Ocean.65 In the Arctic, the U.S. Coast Guard and Navy are pursuing strategies to respond to the changing geopolitical significance resulting from the projected absence of summer sea ice in the next few decades (Ch. 2: Climate, KM 7).66 ,67 ,68 ,69
The risks climate change may hold for national security more broadly are connected to the relationships between climate-related stresses on societies and conflict. Direct linkages between climate-related stress and conflict are unclear,70 but climate variability has been shown to affect conflict through intermediate processes, including resource competition, commodity price shocks, and food insecurity.71 ,72 The potential for conflict increases where there is a history of civil violence, conflict elsewhere in the region, low GDP or economic growth, economic shocks, weak governance, and lack of access to basic needs.61 For example, droughts around the world in 2010 contributed to a doubling of global wheat prices in 2011 and a tripling of bread prices in Egypt.73 This and other factors, including national trade policy and poverty, contributed to the civil unrest that ultimately resulted in the 2011 Egyptian revolution.73 While the 2010 droughts were not the sole cause of the revolution, they contributed to destabilization of an already unstable region. Likewise, drought in Somalia has forced herders to sell livestock they could not provide for, reducing their incomes and leading some to join armed groups.74 Water scarcity and climate-related variations in water availability can increase tensions and conflict between countries.75 In these and other instances, conflict was related to stress from climate-related events, but non-climatic factors also had an important role.76 ,77 ,78 ,79 ,80 ,81 ,82 ,83 However, in some cases, water scarcity and variability can result in cooperation rather than conflict.61 ,84
Human migration is another potential national security issue. Extreme weather events can in some cases result in population displacement. For example, in 1999 the United States granted Temporary Protected Status to 57,000 Honduran and 2,550 Nicaraguan nationals in response to Hurricane Mitch.85 In 2013, more than 4 million people were internally displaced by Typhoon Haiyan in the Philippines,86 and the United States committed 13,400 military personnel to the relief effort (Figure 16.3).87 Six months after Typhoon Haiyan, more than 200,000 people remained without adequate shelter.88 While neither Hurricane Mitch nor Typhoon Haiyan was solely attributable to climate change,89 tropical cyclones are projected to increase in intensity, which would increase the risk of forced migration.2 ,49 Slower changes, including sea level rise and reduced agricultural productivity related to changes in temperature and precipitation patterns, could also affect migration patterns.61 However, whether migration in response to climate change will generally cause or exacerbate violent conflict is still uncertain (Ch. 27: Hawai‘i & Pacific Islands, KM 6).90 ,91
Key Message 4 Transboundary Resources: “U.S. international interests, such as economics and trade, international development and humanitarian assistance, national security, and transboundary resources, are affected by impacts from climate change, variability, and extreme events. Long-term changes in climate could lead to large-scale shifts in the global availability and prices of a wide array of agricultural, energy, and other goods, with corresponding impacts on the U.S. economy. Some U.S.-led businesses are already working to reduce their exposure to risks posed by a changing climate…
Climate change, variability, and extreme events increase risks to national security through direct impacts on U.S. military infrastructure and, more broadly, through the relationship between climate-related stress on societies and conflict. Direct linkages between climate and conflict are unclear, but climate variability has been shown to affect conflict through intermediate processes, including resource competition, commodity price shocks, and food insecurity. The U.S. military is working to fully understand these threats and to incorporate projected climate changes into long-term planning. (page 108).”
Box 16.2 Benefits of International Scientific Cooperation on Climate Research “knowledge of climate impacts in regions and sectors of interest to the United States, which can be used to inform decisions about humanitarian and development assistance, national security, and transboundary resource management;51 ,137”
Box 16.3 How Well Are Climate Risks to U.S. International Interests Understood and Addressed? “There is high confidence that climate change, variability, and extreme events can result in profound consequences for U.S. international interests relating to economy and trade (Key Message 1), development and humanitarian assistance (Key Message 2), national security (Key Message 3), and managing shared resources across our borders (Key Message 4). Projections of climate change indicate that these impacts will continue throughout the century and will likely accelerate in the future.3
Despite this level of confidence, the mechanisms by which climate impacts beyond American borders can affect U.S. interests are not uniformly well understood. Some of this uncertainty arises because these impacts are part of complex systems, and understanding how climate change, variability, and extremes affect such systems can be challenging (Ch. 17: Complex Systems). For example, as noted in Key Message 3, the connections between climate and national security are complex because national security can be affected through intermediate processes such as resource competition. Such processes are challenging to model and forecast because they can be affected by such difficult-to-predict factors as policy decisions, human behavior, and climate surprises.147”
Chapter 17: Sectorial Interactions, Multiple Stressors, and Complex Systems (Full Chapter)
Key Message 3 Management of Interacting Systems “Despite the challenge of managing system interactions, there are opportunities to learn from experience to guide future risk management decisions (Ch. 28: Adaptation, KM 3). The financial sector has invested significantly in understanding and managing systemic risks—including those associated with climate change and climate policy.68 Mechanisms include risk assessment, financial disclosures, contingency planning, and the development of regulations and industry standards that recognize system interdependencies. Another example is that of the Department of Defense (DoD), which integrates consideration for the implications of climate change and variability for food, water, energy, human migration, supply chains, conflict, and disasters into decision-making and operations around the world.69 In so doing, the DoD focuses on enhancing preparedness, building partnerships with other public and private organizations, and including climate change in existing planning processes.69 ,70 These strategies are relevant to any organization attempting to enhance its resilience to climate change.”
Chapter 18 Northeast (Full Chapter)
Background “Service infrastructure in the Northeast is at increasing risk of disruption, resulting in lower quality of life, economic declines, and enhanced social inequality.17 Interdependencies across critical infrastructure sectors such as water, energy, transportation, and telecommunication (and related climate security issues) can lead to cascading failures during extreme weather and climate-related disruptions (Ch. 17: Complex Systems).17 ,59 ,60”
Chapter 19 Southeast (Full Chapter)
Case Study: Prescribed Fire “With wildfire projected to increase in the Southeast,6 ,191 prescribed fire (the purposeful ignition of low-intensity fires in a controlled setting), remains the most effective tool for reducing wildfire risk.4 ,195 Department of Defense (DoD) lands represent the largest reservoirs of biodiversity and native ecosystems in the region.117 Military activities are a frequent source of wildfires, but increases in prescribed fire acres (Figure 19.19) show a corresponding decrease in wildfire ignitions for DoD.4 Climate resilience by DoD is further achieved through restoration of native longleaf pine forests that occupy a wide range of site types, including wetland and well-drained soils—the latter leading many to characterize this forest as being drought resistant.196 ,197 ,198 ,199 In addition to proactive adaptation through prescribed fire, DoD has been a leader in climate strategies that include regional conservation planning, ecosystem management, endangered species recovery, and research funding.”
Chapter 23: Southern Great Plains (Full Chapter)
Coastal Areas, Bays, and Estuaries “The Texas coast, with 6.5 million people contributing over $37 billion to the region’s economy, relies on its natural features, bays, and estuaries that serve as storm barriers to protect coastal infrastructure, and on its climate amenities to spur ecosystem services, such as fishing, ecotourism, and the ocean economy. These coastal ecosystems provide protection not only for people but also for 25% of the Nation’s refining capacity, four crucial ports, much of the strategic petroleum reserves, and strategic military deployment and distribution installations. This protection was clearly on display with the recent impacts of Hurricane Harvey, where it has been estimated that natural coastal habitats protected about $2.4 billion worth of property in Texas and thousands of lives, with the suggestion that these habitats are potentially our first lines of defense.130”
Chapter 26 Alaska (Full Chapter)
Key Message 5 Economic Costs Marine Vessel Traffic “Northward progression of the late-summer sea ice edge creates opportunities for increased vessel traffic of various types (including cargo and tanker ships, tour boats, and government vessels, including military)226 to pass through the Bering Strait to or from the Northern Sea Route, the Northwest Passage,228 and, by mid-century, directly across the Arctic Ocean.229 ,230 As the Arctic Ocean opens, the Bering Strait will have increased strategic importance.231 Lack of deep-water ports, vessel services, search and rescue operations, environmental response capabilities, and icebreaking capacity will impede expansion of vessel traffic.225 ,226 ,230 ,232 ,233 Significant effects are likely several decades away, and new transarctic shipping will likely have little economic effects within Alaska in the near term but would bring environmental risks to fisheries and subsistence resources.234 New oil and gas exploration and development in new areas within the U.S. economic zone are unlikely, as the Arctic Ocean waters that are not already accessible are generally off the U.S. continental shelf.
Key Message 6 Adaptation “At the federal level, there are several key motivations for Arctic Strategies created by various U.S. Government agencies, including 1) recognizing the need to adapt to a changing climate, 2) identifying critical research gaps, 3) creating a vision for regional resilience, and 4) acknowledging the need to safeguard national security under changing environmental conditions.264 ,265 ,266”
Chapter 27 Hawai‘i. and U.S.-Affiliated Pacific Islands (Full Chapter)
Background “For example, Hawai‘i has the highest average electricity rate in the United States (more than twice the national average),28 and more than 85% of food is imported on most islands (see Ch. 17: Complex Systems and Ch. 20: U.S. Caribbean, Background and KM 5 for more information on the importance of regional supply chains).29 ,30 ,31 Though the islands are small, they are seats for key military commands, with forces stationed and deployed throughout the region providing strategic defense capabilities to the United States.
Despite the costs and risks, Pacific Islanders have deep ties to the land, ocean, and natural resources, and they place a high value on the environmental, social, and physical benefits associated with living there. Residents engage in diverse livelihoods within the regional economy, such as tourism, fishing, agriculture, military jobs, and industry, and they also enjoy the pleasant climate and recreational opportunities. Important challenges for the region include improving food and water security, managing drought impacts, protecting coastal environments and relocating coastal infrastructure, assessing climate-induced human migration, and increasing coral reef resilience to warming and acidifying oceans.”
Figure 27.9: Potential Economic Loss from Sea Level Rise, O‘ahu, Hawai‘i Figure 27.9: This map highlights potential economic losses (in 2015 dollars) in the exposure area associated with 3.2 feet of sea level rise on the island of O‘ahu, Hawai‘i. Potential economic losses are estimated from impacts to land and residential and commercial infrastructure. Highly impacted areas at risk of large economic losses include the U.S. Pacific Command and military infrastructure concentrated in Pearl Harbor (black circle) and the vulnerable tourist areas surrounding Waikīkī (dashed black circle). Source: adapted by Tetra Tech Inc. from the Hawai‘i Climate Change Mitigation and Adaptation Commission 2017.42
Key Message 6 Cumulative Impacts and Adaptation “Sea level rise, the deterioration of coral reef and mangrove ecosystems (see Key Message 4), and the increased concentration of economic activity will make coastal areas more vulnerable to storms (see Key Message 3).196 Pacific Islands already face underlying economic vulnerabilities and stresses caused by unsustainable development, such as the use of beaches for building materials that results in coastal erosion or the waste disposal on mangroves and reefs that undermines critical ecological functions. The compounding impacts of climate change put the long-term habitability of coral atolls at risk, introducing issues of sovereignty, human and national security,197 and equity,198 ,199 ,200 a subject of discussion at the international level.”
Chapter 28: Reducing Risks Through Adaptation Actions (Full Chapter)
Introduction Individuals, business entities, governments, and civil society as a whole can take adaptation actions at many different scales. Some of these are changes to business operations, adjustments to natural and cultural resource management strategies, targeted capital investments across diverse sectors, and changes to land use and other policies. Adaptation actions can yield beneficial short-term and/or longer-term outcomes in excess of their costs, based on economic returns, ecological benefits, and broader concepts of social welfare and security.
Key Message 3 Adaptation Entails Iterative Risk Management Iterative risk management is consistent with most of the elements in the many climate adaptation efforts and approaches currently in use,42 ,43including climate vulnerability assessment, iterative risk assessment, and adaptive management as often practiced by federal and other land and resource management agencies,44 as well as disaster risk management.45 Using a comprehensive framework helps highlight commonalities and differences across the approaches used by different jurisdictions and sectors, facilitating comparison and learning among their users. It also situates climate adaptation squarely within the broad range of other risk management activities, such as in the financial, engineering, environmental, health, and national security sectors.2
Key Message 4 – Benefits of Proactive Adaptation Exceed Costs “Proactive adaptation initiatives—including changes to policies, business operations, capital investments, and other steps—yield benefits in excess of their costs in the near term, as well as over the long term. Evaluating adaptation strategies involves consideration of equity, justice, cultural heritage, the environment, health, and national security. (pg 165)”
Broader Measures of Well-Being Benefit–cost analysis provides one important, but not the sole, means to evaluate alternative adaptation actions. Effective adaptation can provide a broad range of benefits that can be difficult to quantify, including improvements in economic opportunity, human health, equity, national security, education, social connectivity, and sense of place, while safeguarding cultural resources and practices and enhancing general environmental quality.
“In general, adaptation can generate significant benefits in excess of its costs. Benefit–cost analysis can help guide organizations toward actions that most efficiently reduce risks, in particular those that, if not addressed, could prove extremely costly in the future. Beyond those attributes explicitly measured by benefit–cost analysis, effective adaptation can also enhance social welfare in many ways that can be difficult to quantify and that people will value differently, including improving economic opportunity, health, equity, security, education, social connectivity, and sense of place, as well as safeguarding cultural resources and practices and environmental quality.
A significant portion of climate risk can be addressed by mainstreaming; that is, integrating climate adaptation into existing organizational and sectoral investments, policies, and practices, such as planning, budgeting, policy development, and operations and maintenance. Mainstreaming of climate adaptation into existing decision processes has already begun in many areas, such as financial risk reporting, capital investment planning, engineering standards, military planning, and disaster risk management. Further reduction of the risks from climate change, in particular those that arise from futures with high levels of greenhouse gas emissions, calls for new approaches that create conditions for altering regulatory and policy environments, cultural and community resources, economic and financial systems, technology applications, and ecosystems. (pg 166)”
Key Message 5 New Approaches Can Further Reduce Risk
Existing Mainstreaming “Mainstreaming climate adaptation into existing decision processes has begun in many areas, in particular those with well-developed risk management processes such as financial risk reporting, capital investment planning, engineering standards, military planning, and disaster risk management… Other sectors of government and industry are also starting to consider climate risk a major systemic risk. In its 2018 Global Risks Report, the World Economic Forum listed the top five environmental risks—including extreme weather events and temperatures and failures of climate change mitigation and adaptation—in terms of both likelihood and the impact on the global economy.116 The U.S. military now routinely integrates climate risks into its analysis, plans, and programs,117 with particular attention paid to climate effects on force readiness, military bases, and training ranges (Ch. 16: International, KM 3).118 ,119 Naval Station Norfolk, for example, has replaced existing piers with double-decker piers that are elevated by several more feet and thus more resilient to rising sea levels and extreme weather events (Ch. 1: Overview, Figure 1.8).”