Most military bases occupy large areas of undeveloped or sparsely developed land relative to surroundings. These lands and their ecosystems provide a wide range of valuable services to society including flood protection, habitat for plant and wildlife species, recreational opportunities, and carbon sequestration. The DoD manages natural ecosystems, including deserts, coastal areas, and Arctic systems, on nearly 28 million acres of land to provide realistic training environments. SERDP and ESTCP projects enable the DoD to comply with federal environmental legislation and regulations, including the Endangered Species Act of 1973 (as amended), and ensure DoD lands and ecosystems are resilient to changing climate conditions.