Forests are areas of land covered with trees or other woody vegetation.
Forests occur within urban areas, at the interface between urban and rural areas, and in rural areas. Urban forests and open spaces contribute to clean air, cooling buildings, aesthetics, and recreation in parks. Development in the wildland-urban interface is increasing because of the appeal of owning homes near or in the woods. In rural areas, market factors drive land uses among commercial forestry and land uses such as agriculture. Across this spectrum, forests provide recreational opportunities, cultural resources, and social values such as aesthetics.
In the United States, EPA reports that forests occupy approximately 751 million acres – about one third of the country’s total land area. These forests provide many benefits and services, including recreation, clean air and water, wildlife habitat, carbon storage, and a variety of forest products. Climate influences the structure and function of forest ecosystems and plays an essential role in forest health. Climate changes may exacerbate existing stressors to forests, such as pest outbreaks, fires, drought, and human development.
Climate change is impacting and could continue to affect forest lands in a variety of ways. Forest systems are sensitive to changes in temperature, precipitation, and snow-melt, as well as expanded ranges of fire, insects and disease outbreaks. Climate changes directly and indirectly affect the growth and productivity of forests—directly due to changes in atmospheric carbon dioxide and climate, and indirectly through complex interactions in forest ecosystems. Climate also affects the frequency and severity of many forest disturbances. Learn more about impacts on forest health due to disturbance.
The impacts of climate change are likely to worsen many problems that forested areas already face. Changing temperatures and water regimes, earlier snow-melt, and increased resource demands due to human development can impose negative pressures on these systems. In conjunction with the projected impacts of climate change, forests face ongoing impacts from land development, suppression of natural periodic forest fires, and air pollution. Although it is difficult to separate the effects of these different factors, the combined impact is already leading to changes in our forests. As these changes are likely to continue in the decades ahead, some of the valuable goods and services provided by forests may be compromised. To learn more about examples of projected regional changes in forests, see the EPA’s Northeast, Southeast, Southwest, and Alaska regional impacts pages. Impacts to forest growth and productivity are also likely due to increases in carbon dioxide and changes in temperature and precipitation. Learn more about impacts on forest growth and productivity.
While climate change poses many management challenges for forested landscapes, it also presents management opportunities. Diverse stakeholder groups including agencies, conservation organizations such as land trusts, and the private sector are working together across the country to identify enhanced management approaches that can protect the multiple benefits forest lands provide. For example, in California, the Pacific Forest Trust (PFT) worked with other partners and the state legislature to include forest carbon mitigation projects in the state’s carbon reduction bill AB 32. Since 2002, PFT has supported the launch of nearly a dozen carbon offset projects throughout the U.S., and continues to conduct advocacy and education to encourage expanded conservation and carbon mitigation opportunities. In Maine, the Downeast Lakes Land Trust (DLLT) similarly launched a qualifying AB 32 carbon offset project on their working forest lands. Funds from the purchase of the carbon credits from DLLT’s project are being used to support the acquisition of additional priority lands. Similarly, in the Lower Mississippi Basin, The Conservation Fund has been restoring marginal agricultural lands to bottomland hardwood forests, enhancing water quality and retiring carbon offset credits in the process. Read more forest land case studies.
As the 2014 National Climate Assessment reports, forests provide opportunities to reduce future climate change by capturing and storing carbon, as well as by providing resources for bioenergy production (the use of forest-derived plant-based materials for energy production). The total amount of carbon stored in U.S. forest ecosystems and wood products (such as lumber and pulpwood) equals roughly 25 years of U.S. heat-trapping gas emissions at current rates of emission, providing an important national “sink” that could grow or shrink depending on the extent of climate change, forest management practices, policy decisions, and other factors., For example, in 2011, U.S. forest ecosystems and the associated wood products industry captured and stored roughly 16% of all carbon dioxide emitted by fossil fuel burning in the United States.
Management challenges and opportunities for public, private, and tribal forests involve similar issues. For example, increases in wildfire, disease, drought, and extreme events are projected for some regions. Learn more about regional impacts and resources here. At the same time, there is growing awareness that forests may play an expanded role in carbon management. Urban expansion fragments forests and may limit forest management options. Addressing climate change effects on forestlands requires considering the interactions among land-use practices, energy options, and climate change. Additionally, managers of forest lands are implementing adaptation measures to help build resilience to changing climate conditions. Learn more about forest adaptation measures.
While there is no one-size-fits-all approach to address climate impacts, more and more, conservation organizations are working with their communities to identify opportunities to reduce vulnerabilities and build resilience to prepare for changing temperatures. Agencies are making similar strides to implement projects that reduce risks and plan for resilience by incorporating adaptation, mitigation, and engagement into their strategic goals and objectives.
– Climate Impacts on Forests, EPA
– Climate Change Resource Center, USDA / Forest Service
– Forests and Global Climate Change: Potential Impacts on U.S. Forest Resources, Pew Center on Global Climate Change
– Effects of Climatic Variability and Change on Forest Ecosystems: A Comprehensive Science Synthesis for the U.S. Forest Sector, USDA / Forest Service
– National Climate Change Assessment Report: Forests, US Global Change Research Program