Skip to main content
U.S. flag

An official website of the United States government

Fifth National Climate Assessment - Read the Report

Department of Defense

Department of Defense logo

The Department of Defense (DoD) recognizes that global changes in the environment impact DoD operations and installations. In alignment with the National Defense Strategy (NDS), the DoD Directive 4715.21 Climate Change Adaptation and Resilience, and the Department’s 2019 Arctic Strategy, DoD seeks to understand, prepare, and respond to the impact of global environmental changes. DoD’s Research, Development, Test, and Evaluation (RDT&E) activities, as well as interagency and international collaboration through USGCRP, play a critical role in DoD’s efforts to address global environmental change. DoD manages and executes RDT&E activities across the Military Services that respond to specific national security requirements and may also be leveraged to address the strategic goals of the USGCRP. DoD’s environmental RDT&E efforts focus on building awareness of the changing operational physical environment through observations and predictive models and enhancing operations in those changing environments via mitigation, adaptation, and resilience. In meeting the requirements within Executive Order (EO) 14008, Tackling the Climate Crisis at Home and Abroad, DoD released agency-wide documents, including the Defense Climate Risk Analysis report (2021), to incorporate climate change security implications across relevant DoD strategy, planning, and programming documents and processes. The DoD Climate Adaptation Plan (2021), and its subsequent Progress Report (2022), was also released to articulate a bold vision for climate adaptation and align adaptation and resilience efforts with the Department’s warfighting mission. Some DoD initiatives related to environmental change and resilience include the following:

  • The Army continues to develop mobility and infrastructure advancements that reduce energy demand and increase resilience and capabilities in the Arctic and other environments in line with their 2022 Climate Strategy and Implementation Plan.

  • The Navy is developing global weather, ocean, and sea ice prediction models at the seasonal (months) timescale as well as exploring new platforms for sustained observational capability in the Arctic. The Department of the Navy also released its Climate Action 2030 report in 2022.

  • The Department of the Air Force published its Climate Action Plan (DAF CAP) in October 2022 and in July 2023 finalized its Climate Campaign Plan, which is the implementation plan for the DAF CAP. 

  • The Navy and the Air Force are collaborating with U.S. interagency partners on Earth system modeling, developing the next generation of predictive models.

  • Since FY2019, the Office of the Deputy Assistant Secretary of Defense, Environment and Energy Resilience continues to evolve the DoD Climate Assessment Tool (DCAT). This tool is a Department-wide screening-level climate change hazard exposure assessment tool based on an existing geospatial tool developed by the U.S. Army Corps of Engineers (USACE) for the Department of Army (Office of the Assistant Secretary for the Army for Installations, Energy, and Environment). The DoD Regional Sea Level (DRSL) database tool provides projections of sea-level change and extreme water levels globally for DCAT and is also publicly accessible. DoD is enhancing DCAT and expanding the installations included in the tool to assess exposure as well as vulnerability (including adaptive capacity and sensitivity) to climate change and weather impacts.

  • Two years ago, at the Climate Leaders’ Summit led by President Joseph R. Biden Jr., Honorable Secretary of Defense Lloyd J. Austin III committed to produce tailored versions of DCAT for six allies: Australia, Germany, Italy, Japan, Republic of Korea, and the United Kingdom. On April 20, 2023, the Pentagon hosted a Climate Assessment Tool Ceremonial event with embassy staff from the allies to mark the successful development of these tools. DoD continues to develop additional tailored versions of DCAT for other partner nations and allies. 

  • The Strategic Environmental Research and Development Program (SERDP) and the Environmental Security Technology Certification Program (ESTCP) are DoD’s environmental, resilience, and installation energy and water research programs, investing in and harnessing the latest science and technology to improve DoD’s overall resilience to environmental threats, extreme weather and climate change impacts. Since 2009, SERDP-ESTCP has sponsored nearly 50 projects in the climate projection temporal space including these recent applicable studies: Linked Rainfall and Runoff Intensity-Duration-Frequency in the Face of Climate Change and Uncertainty; Changes in Climate and its Effect on Timing of Snowmelt and Intensity-Duration-Frequency Curves; Exploring the Basis for Skillful Projections of Decision-Relevant Climate Normals; Developing an Experimental Predictive Framework for Climate Regime Shifts and Their Impacts Within a 2-20 Year Outlook Window; Fit for Purpose? An Integrative Assessment of State-of-the-Science Downscaling Methods for DoD Infrastructure Planning; Development of a Decision Support Aid System Connecting Climate Model Downscaling and DoD Infrastructure; Updated International Climate Change Data for DOD Climate Assessment Tool (DCAT). 

Finally, the Department more broadly sponsors basic research in a number of potentially relevant areas, such as marine meteorology, physical oceanography, polar science and engineering, biogeochemical sciences, and terrestrial science and phenomenology.