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Fifth National Climate Assessment - Read the Report

Terrestrial Carbon Storage

Carbon is stored in living and dead organic matter above and below the ground. Changes in terrestrial (or land-based) ecosystems—for instance, as a result of climate or land use changes—can contribute to changes in carbon storage, which in turn can affect the climate system through the release of greenhouse gases such as carbon dioxide.

Forests (not including urban forests) accounted for 95% of the terrestrial carbon stored in 2019. In recent years, croplands and grasslands have become net carbon dioxide sources. With the exception of one year since 2009, more carbon dioxide has been released annually than stored in croplands and grasslands.

Forests (not including urban forests) accounted for 95% of the terrestrial carbon stored in 2019. In recent years, croplands and grasslands have become net carbon dioxide sources. With the exception of one year since 2009, more carbon dioxide has been released annually than stored in croplands and grasslands.

Date Range: 1990 - 2019

Storage of Carbon Across U.S. Land-Based Ecosystems Is Changing

Terrestrial ecosystems store large amounts of carbon dioxide each year: for example, net annual carbon dioxide storage by forests, urban forests, croplands, and grasslands totaled 785.5 million metric tons in 2019.

Forests (not including urban forests) annually store the majority of terrestrial carbon dioxide in the United States. Croplands and grasslands are generally net carbon dioxide sources, releasing more carbon dioxide than they are storing.

Why It's Important

  • Changes affecting these ecosystems—such as alterations in climate or land use— can contribute to changes in carbon storage, which in turn can affect the climate system through the release of greenhouse gases.

  • This indicator can help decision makers understand how climate change, land management, natural disturbances, and ecosystem dynamics affect annual terrestrial carbon storage in the United States.

About Terrestrial Carbon Storage

The data shown in the graph were drawn from the U.S. Environmental Protection Agency (EPA) Inventory of Greenhouse Gas Emissions and Sinks, in which annual carbon dioxide storage is estimated using three complementary datasets: the U.S. Department of Agriculture (USDA) National Resources Inventory, the USDA Forest Service Forest Inventory and Analysis, and the Multi-Resolution Land Characteristics Consortium National Land Cover Dataset. These datasets represent a combination of statistical survey approaches and satellite data. Changes to terrestrial carbon storage reflect the impacts of many factors.