The Fifth National Climate Assessment (NCA5) highlights the ways in which all regions in the United States are currently experiencing harmful impacts of climate change.
One of the most direct ways that Americans experience climate change is through increases in the frequency and intensity of extreme weather events. So far this year, the United States has already experienced 25 weather and climate disasters that each resulted in more than a billion dollars of damages, costing hundreds of lives and more than $73 billion total. For some extreme weather events like Hurricane Idalia and the fires in Hawai‘i, the full cost is not yet completely known. Actions taken by President Biden through the Bipartisan Infrastructure Law, Inflation Reduction Act and CHIPS for America Act are helping Americans prepare for, and respond to extreme weather events, as well as a spectrum of other climate-related challenges.
Climate disasters that occur in one region of the United States can have cascading or compounding effects in other regions. For example, wildfires in one region can worsen air quality and health in other regions. When hazards occur in different regions but at the same time, such as the simultaneous megafires that burned across multiple western states and record back-to-back Atlantic hurricanes in 2020, these compounding disasters can put unprecedented demand on federal emergency response resources. Climate change also interacts with other stressors, such as the COVID-19 pandemic and social inequities, which can multiply harm and further increase demand for resources that are needed when responding to disasters. This is particularly true for overburdened communities. These interactions can lead to cascading impacts that cross state and national borders. For example, both gradual changes in average climate conditions (e.g., shifts in temperature and precipitation) and extreme events (e.g., floods, droughts, and wildfire) can shock the global food supply chain and lead to food insecurity, geopolitical instability, and mass migration. These cascading and compounding impacts affect people’s well-being, our economy, and our national security.
In addition to federal action, state, local, Tribal, and territorial efforts to adapt to climate change and reduce greenhouse gas emissions have expanded in every U.S. region. Many of these actions advance climate mitigation and adaptation at the same time. Effective climate action has prioritized equitable and inclusive planning processes to help ensure that affected communities can participate in decision-making. Across the country, mitigation and adaptation efforts that build upon community strengths and center local and Indigenous Knowledge systems improve resilience.
The Fifth National Climate Assessment includes ten regional chapters that assess climate risks and describe challenges, opportunities, and success stories for managing those risks. In addition, the new NCA Atlas allows users to explore localized climate projections to inform climate resilience, adaptation, and mitigation efforts in their communities.
Climate Change Impacts in Regions Across America
Northeast — Connecticut, Delaware, District of Columbia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, West Virginia
This region is experiencing increases in the frequency of extreme weather events and other climate-driven changes, including intense rainstorms, warmer ocean temperatures, and rapid sea level rise. For example, the amount of rain that falls during the heaviest downpours has increased by approximately 60% in the Northeast since the 1950s—the largest increase in the United States. Many regional climate impacts, including extreme heat and flooding, disproportionately impact low-income communities and communities of color. The region is responding with mitigation and adaptation efforts, such as the Regional Greenhouse Gas Initiative—a market-based program aimed at reducing carbon dioxide emissions; eight state laws requiring emissions reductions of at least 80% by 2050; and new financing options, such as grants, loans, or tax assessments, that improve the capacity of households, communities, and businesses to build climate resilience. Cities, states, and Tribes are implementing climate action plans with innovative approaches that embrace inclusive and equitable processes. For example, Pittsburgh, Pennsylvania’s Climate Action Plan was developed with multi-year civic engagement opportunities, focuses on benefits of climate action that improve equity, and tracks progress through annual reports. The city’s 2022 stormwater code requires any new development that could affect stormwater runoff to plan for projected increases in heavy rainfall under climate change, rather than building to historical rainfall amounts. Read more in Chapter 21: Northeast.
Southeast — Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia
This region’s growing population faces rising sea levels and increasing frequency, intensity, and duration of heat waves that lead to greater risks of wildfires. Climate stressors, including drought and extreme heat, are expected to disproportionately affect communities of color and low-income communities who struggle to afford energy bills, especially for air conditioning. Due to increasing energy demands and extreme weather events, there is a growing number of power outages in the region that affect more than 1,000 residents for longer than an hour. This is especially true during the warmer months that place some communities at a higher risk of heat exposure and heat-related illness due to a lack of access to air conditioning. While adaptation efforts tend to be concentrated in wealthier coastal and metropolitan areas, there have been notable advancements in climate actions throughout the region. Following repeated flooding from multiple hurricanes, measures to reduce flood risk in Princeville, North Carolina, include buyouts, elevating homes, and building housing that meets local flood standards. In Orlando, Florida, the city government and businesses are adopting commercial building energy efficiency requirements and a community-wide commitment to 100% renewable energy to advance the decarbonization of local buildings. As the largest rental car market in the world, the metropolitan area has also adopted new electric vehicle readiness policies. Read more in Chapter 22: Southeast.
U.S. Caribbean — Puerto Rico, U.S. Virgin Islands
Warmer air and ocean temperatures are leading to intense hurricanes and increasingly powerful storms. The number of Category 4 and 5 hurricanes is projected to increase as the climate crisis worsens. In 2017, Hurricane Maria caused more than $2.3 billion in losses and damages to crops and infrastructure, which represented a reduction of about 80% of the main island’s total agricultural value. Paired with rising sea levels and other climate changes, these impacts are harming human health—particularly in underserved communities; degrading, disrupting, and undermining the functions of ecosystems, especially in coastal zones; and threatening the region’s water and food security. Critical infrastructure in Puerto Rico and the U.S. Virgin Islands is at risk of flooding due to sea level rise and heavy rainfall. Changes in precipitation and extreme events are expected to increase outbreaks of disease and can also disrupt vital local services, such as health care and water quality management. Across the region, many community-based organizations have taken actions to advance adaptation, social transformation, and sustainable development. Effective adaptation to support resilience in the region could be enhanced by decentralization of energy and water systems, improved governance and funding, and stronger partnerships across the Caribbean region and the U.S. mainland. For example, decentralized household solar systems and rainwater harvesting improve resilience by providing power and water during interruptions to the centralized utility grid or public water system. Read more in Chapter 23: U.S. Caribbean.
Midwest — Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, Wisconsin
The Midwest is facing rising temperatures, drought, extreme precipitation, and other climate changes. These changes affect Midwestern ecosystems, agriculture, infrastructure, and human health, as well as livelihoods and cultural practices that rely on natural resources, including ice fishing or the harvesting of local plant species. Since 1980, the Midwest has incurred more than $49 billion in economic damages due to flooding. Although average corn and soybean yields have increased in recent decades, both flooding and extreme droughts significantly decreased corn yields in some locations and in some years by up to 37%. Over the past decade, clean energy production in the region has grown by more than 275% and has reduced carbon emissions from the energy sector. Communities, local and state governments, and businesses are embracing adaptation approaches that include green infrastructure, climate-smart agriculture, and collaboration with Tribes on land management issues to improve climate outcomes for all residents. For example, climate-smart agricultural approaches have the potential to increase production, improve resilience to climate-related risks, and yield additional benefits for Midwestern ecosystems. An innovative finance and construction approach being used by the Milwaukee Metropolitan Sewer District has reduced the number of annual combined sewer overflow events over the last five years. Using a community-based public-private partnership, Milwaukee is now looking to add an additional 20 million gallons of green stormwater infrastructure capture capacity. Read more in Chapter 24: Midwest.
Northern Great Plains — Montana, Nebraska, North Dakota, South Dakota, Wyoming
The Northern Great Plains are experiencing unprecedented extremes, including severe droughts, floods, and wildfires. Climate change can affect floods along the Missouri River, like the ones in 2011 and 2019 that caused evacuations, costly damages, and interstate closures. With additional global warming, the region would expect to see some of the highest increases in annual flooding damage costs in the United States. At the same time, drought is projected to increase, with moderate to extreme droughts occurring as much as 20% more frequently by the end of the century. These changes threaten economic sectors, such as agriculture and recreation, and affect the mental and physical health of residents. The region’s share of employees working in fossil fuel extraction is four times greater than in the nation as a whole. Shifts in energy demand, production, and policy will affect energy-related livelihoods for the region’s residents, especially rural, Indigenous, and low-income immigrant populations, as opportunities in the clean energy field expand. Renewable energy production is on the rise in the Northern Great Plains, with the region supplying 12% of the total U.S. electricity generation from wind, biomass, and solar sources. In addition, the region is home to a number of Tribes who are leading the nation’s clean energy transition by installing clean energy sources such as wind, solar, and hydropower. Read more in Chapter 25: Northern Great Plains.
Southern Great Plains — Kansas, Oklahoma, Texas
Increasing frequency and intensity of precipitation, warmer ocean temperatures, extreme heat, and rising sea levels are degrading the air, lands, and waters that people in the Southern Great Plains rely on for economic, recreational, and cultural activities. Annual precipitation has increased across most of the region, with Texas enduring its five wettest months on record between 2000 and 2021. By contrast, the region also experienced severe to exceptional drought for significant portions of the years between 2010 and 2022. Between 2018 and 2022, 52 individual billion-dollar climate-related disasters affected all or part of the region. By 2050, annual average temperatures are projected to exceed historical record levels in all three states. These impacts compound existing burdens on disadvantaged communities that have the fewest resources to prepare and adapt to climate change. Communities are adapting through nature-based solutions, reliance on Indigenous and local knowledge, and resilient infrastructure that enhances public health and the region’s economy. In 2020, Oklahoma City produced its first sustainability plan to address climate change. Austin, San Antonio, and Dallas, Texas, adopted plans that included both mitigation and adaptation actions and have started to address local equity issues. Throughout the Southern Great Plains, a major shift in energy generation from fossil fuels toward renewables is underway, with the region accounting for 42% of national wind-generated electricity in 2022. This shift in the demand for clean energy is reducing emissions and creating new jobs and cleaner air in the region. Read more in Chapter 26: Southern Great Plains.
Northwest — Idaho, Oregon, Washington
Higher temperatures are leading to declining snowpack, melting glaciers, and rising sea levels. These changes, combined with increasing risks of flooding, wildfires, and other climate hazards, threaten human health, ecosystems, infrastructure, and industries. For example, the record-breaking Pacific Northwest heatwave of June 2021 led to more than 1,400 heat-related deaths, a subsequent severe wildfire season, significant losses of economically important fishery species, and total damages exceeding $38.5 billion. Impacts on the Northwest’s economy will have cascading effects on livelihoods and well-being of residents. For instance, snow-based recreational industries, such as skiing, have already lost revenue due to a decrease in snow days per calendar year. In parts of the Cascade Range, the snow season is projected to decrease by nearly half by the end of the century. In response to these changes, local governments, Tribes, labor unions, and community groups across the region are adopting policies and programs that support a just transition to a low-carbon future. State and local climate policies in the Northwest are prioritizing climate response strategies that recognize the importance of climate justice, such as subsidizing adaptation, redistributing benefits, and reducing harm to frontline communities. The Quinault Indian Nation is adapting to accelerated loss of land caused by sea level rise, flooding, and erosion along the central coast of Washington State by reacquiring fractionated land and relocating housing and key facilities from their traditional village site to a newly developed site at higher elevation. Read more in Chapter 27: Northwest.
Southwest — Arizona, California, Colorado, Nevada, New Mexico, Utah
Climate change is threatening water resources, increasing challenges to food and fiber production, and compromising human health in the Southwest through drought, wildfire, intense precipitation, sea level rise, and marine heatwaves. Since 2018, 31 climate- and weather-related disasters that have each resulted in more than a billion dollars in damages have affected the Southwest, resulting in more than 700 deaths and estimated damages totaling $67.3 billion. Climate-driven changes to infrastructure, agriculture, fisheries, and other economic sectors are impacting some communities disproportionately. These communities include farmers and ranchers, especially Hispanic, women, and migrant farmworkers; food-insecure households; Indigenous Peoples facing water access challenges; and coastal communities that are reliant on a declining population of traditional fish species. In response, state and local municipalities across the Southwest have implemented adaptive water governance and management approaches. After more than 22 years of historic drought, the U.S. Bureau of Reclamation declared the first-ever water shortage on the Colorado River in August 2021. The federal governments of the United States and Mexico, the seven U.S. Colorado River basin states, and Indigenous Peoples are developing a range of adaptation pathways and solutions to enhance long-standing collaboration on the Colorado River, including modeling the impact of more extreme climate change scenarios on water resources in the basin. Efforts to mitigate greenhouse gas emissions are also being implemented throughout the region. For example, the Phoenix, Arizona Climate Action Plan states that the city is on track to meet its goal of 50% reduction in greenhouse gas emissions by 2030. Read more in Chapter 28: Southwest.
Alaska is warming two to three times faster than the global average, with increases in annual average temperatures since 1971 as high as 6.2°F in northern Alaska. A 2019 summer heatwave brought record-high temperatures to southern and Interior Alaska, with daily high temperatures exceeding normal by more than 20°F. The Alaska snowfall season is projected to shorten and snowpack is projected to decrease significantly in the southern and western parts of the state. Warming temperatures, thawing permafrost, and other climate-related changes are damaging ecosystems, disrupting cultural practices, harming fisheries and other livelihoods, exacerbating health disparities, and placing critical infrastructure at risk. Many Alaskans, particularly Alaska Native Peoples, depend on natural resources and have a distinct connection to and understanding of the natural environment. While these communities foster self-reliance and resilience in light of a changing climate, geographical isolation and distance from health care and other services leave many people vulnerable to the health impacts of climate change. In recent years, Alaska has emerged as a leader of climate adaptation initiatives in the Arctic, many of which have been implemented by regional entities and municipal, community, and Tribal governments. For example, to address climate threats to traditional foods, the Chugach Regional Resources Commission, an inter-Tribal fish and wildlife commission in Alaska, is integrating Indigenous Knowledge and Western scientific methods in its adaptation efforts, including weekly water sampling for harmful algal blooms, kelp farming, and restoring clam populations. Community renewable energy initiatives like Thermalize Juneau and the Solarize initiatives in Anchorage, Fairbanks, Kenai, Mat-Su, and Palmer help residential and commercial property owners install solar capacity. Read more in Chapter 29: Alaska.
Hawai’i and U.S.-Affiliated Pacific Islands (Commonwealth of the Northern Mariana Islands; American Sāmoa, Guam, the Pacific Remote Islands, the Federated States of Micronesia, the Republic of the Marshall Islands, and the Republic of Palau) Warmer sea surface temperatures, sea level rise, and ocean acidification are degrading coral reefs, resulting in coastal damages that cost approximately $1.2 billion each year for the economies of Hawaiʻi and the U.S. Pacific territories. By 2050, fisheries catch are projected to decline by 40% compared to the early 2000s. These climate changes impair access to clean water and healthy food, undermine human health, threaten cultural resources and the built environment, exacerbate inequities, disrupt economic activity, and damage diverse ecosystems across the region. Strategies are being developed and implemented across the region to revitalize healthier traditional food systems, resulting in more just access to food. Subsistence-based food system practices have sustained Pacific Island peoples for millennia and have aided in recoveries from natural disasters such as typhoons and tsunamis. Other promising fisheries adaptations include establishing networks of marine protected areas to preserve coastal resources, safeguarding fish habitats from pollution runoff, and restoring traditional fishpond mariculture. To help mitigate climate change, the Kauaʻi Island Utility Cooperative achieved a nearly 70% renewable portfolio standard in 2021, and the island is sometimes 100% renewably powered during midday hours. Meanwhile, U.S. Affiliated Pacific Islands plan to use blue carbon ecosystems, including mangroves and seagrasses, to offset emissions while also protecting coastal infrastructure. Read more in Chapter 30: Hawai’i and US Affiliated Pacific Islands.