Overview of Climate Change Threats - Updated

Overview of Climate Change Threats to U.S. Navy and Marine Corps Operations

Dan Linehan, Kellen Jones, Kristen Fletcher, and Tom Murphree  |  September 6, 2024

Overview of Climate Change Threats to U.S. Navy and Marine Corps Operations

Shown steaming to Puerto Rico to help the survivors after Hurricane Maria devastated the island, the hospital ship USNS Comfort (in background) assisted with the Navy’s humanitarian efforts. For decades, sea surface temperatures have been steadily increasing. Higher than normal sea surface temperatures increase the energy that feeds hurricanes, making them stronger and more deadly. (U.S. Navy photo by Petty Officer 3rd Class Dana Legg)

Secretary of the Navy Carlos Del Toro addressed the clear and present dangers from the intensifying climate crisis in his October 2021 One Navy-Marine Corps Team: Strategic Guidance from the Secretary of the Navy.

In his guidance, he stated: "It is a national security and warfighting imperative for the Department of the Navy to address the impact of climate change on our readiness, operations, and ability to fight and win. Climate change seriously increases the potential for greater conflicts on a global scale. We must be prepared to understand increased threats to other nations and the impact they may have on our own national security interests.

"Climate change increases risk and exposes vulnerabilities to our people, installations, platforms, and operations, and it impacts and expands the mission set our naval forces must support. Our Department will stand as a global leader in taking action on and adapting to climate change. We will develop a climate-cognizant force that considers climate elements through all aspects of training and equipping the force and planning and executing the mission."

Surface Ships Aircraft Submarines Marines UAS Installations Electromagnetic Systems Storms Wind and Waves'

Climate change threatens many areas of Navy and Marine Corps operations. Shown here are details of threats to nine areas, including operations conducted by surface ships, aircraft and submarines. Click on the right and left navigation arrows to scroll through the images. For a full-size and printable version of this graphic, click here. (Graphic by Andre Adams, Dan Linehan and Flo Zeuthen)

The following nine areas of Navy and Marine Corps operations are significantly threatened by climate change, and the resulting impacts jeopardize operational capabilities and readiness at home and abroad.

1. Surface Ships: Climate change is causing shifts in weather patterns that will alter the geographic distribution and increase the frequency of severe storms at sea, the intensity of winds and waves, the variability of currents, and the occurrence of extreme temperatures. Rising sea levels and increased frequency of extreme weather, including hurricanes and typhoons, pose heightened risks to ship safety and mission success. Naval forces must adapt to these challenges through enhanced ship design, strategic planning, and operational flexibility to maintain effectiveness in an increasingly unpredictable maritime environment. Additionally, newly opened polar sea routes from warming will present challenges for ship operations. For example, projected summer transpolar sea routes and changing Arctic weather patterns will introduce new safety and operational challenges as naval operations adapt to the evolving Arctic.

The coastal mountains and glaciers along the Gulf of Alaska dwarf the aircraft carrier USS Theodore Roosevelt. Since 2002, from Greenland and Antarctica alone, 420 billion metric tons of glacial ice per year has melted into the oceans, continuing to cause sea level rise and threaten coastal communities and infrastructure across the globe. For comparison, this carrier weighs 97,933 metric tons fully loaded. (U.S. Navy photo by Petty Officer 3rd Class Erick Parsons)

2. Aircraft: Climate change significantly impacts military aviation operations by increasing the frequency of extreme weather events, which disrupt missions, damage infrastructure, and pose increased safety risks. Extreme heat can impair aircraft performance, reduce payload capacity, and threaten crew health. Changes in atmospheric conditions, such as more frequent icing and altered wind patterns, complicate mission planning and increase fuel consumption. Climate change drives greater demand for humanitarian missions and contributes to regional instability, requiring military forces to adapt through enhanced resilience, strategic planning, and technological innovation.

An MH-60S Sea Hawk assists California Department of Forestry and Fire Protection fighting a wildfire at Marine Corps Base Camp Pendleton (left). An aircrew from Helicopter Sea Combat Squadron 3 fills a firefighting bucket as they fight wildfires near Naval Base Ventura County Point Mugu's base housing (right). Higher than normal temperatures and prolonged droughts lead to more frequent and more intense burning wildfires. (U.S. Navy Photos by Mass Communication Specialist 1st Class Joan E. Jennings (left) and Petty Officer 1st Class Chris Fahey (right))

3. Submarines: Climate change impacts submarine operations by altering ocean conditions, affecting navigation, stealth, and mission planning. Rising sea temperatures and changing salinity levels can disrupt sonar performance, making it harder to detect or avoid other vessels. Melting polar ice opens new areas for submarine operations but also introduces hazards such as unpredictable ice movements and shifting currents. More frequent extreme weather can complicate surface operations, including deployment, recovery, and rescue missions. Submarines must adapt through advanced technology and revised operational strategies to maintain effectiveness in evolving underwater environments.

4. Expeditionary Forces: Climate change alters, limits, and constrains the environment expeditionary forces encounter during operations in more extreme ways than previously encountered. Sea level rise laterally expands the extent of shallow water. This shifts the position of the coastline and can lead to different physical coastal conditions, forcing Marines and equipment used for amphibious operations to adjust resources and tactics. High winds and seas reduce the performance and operational availability of landing craft and support platforms. Extreme weather conditions make distributed maritime operations more difficult to coordinate and support, expeditionary advanced bases more difficult to establish, and littoral operations in contested environments more vulnerable. Personnel exposed to more frequent extreme heat face greater likelihood of heat-related injuries to include heat stroke, which can be fatal.

Marines use a tactical water distribution system to pump purified water, which can support expeditionary forces in austere environments (left). Preparing to attach to a Marine Corps unit, a medic hydrates during a training exercise (right). The rising global temperature causes the increasing frequency of extreme temperatures and life-threatening heatwaves. (U.S. Marine Corps photos by Cpl. Joey Holeman (left) and Lance Cpl. Jaiden O. Sangster (right))

5. Uncrewed Autonomous Systems: Climate change affects military uncrewed autonomous systems by introducing challenges related to extreme weather, environmental variability, and operational durability. Increased frequency of extreme weather, high winds, and extreme temperatures can disrupt uncrewed system operations, reducing their reliability and effectiveness. In coastal and polar regions, rising sea levels and melting ice create new operational environments that may require enhanced navigational systems and environmental sensors. Changing climate conditions can complicate the logistics of deploying, maintaining, and powering these systems, necessitating advancements in design and technology to ensure resilience and mission success.

6. Installations: Climate change poses significant risks to military installations by increasing the frequency of extreme weather events, such as hurricanes, floods, and wildfires, which can damage infrastructure and disrupt operations. Rising sea levels threaten coastal bases with flooding and erosion, potentially requiring costly relocations or fortifications. Extreme heat and changing climate patterns can strain energy and water resources, impacting the sustainability of installations. These environmental changes can affect the readiness and safety of personnel, requiring military installations to enhance their resilience through improved infrastructure, disaster preparedness, and sustainable resource management.

A wildfire burned approximately 4,000 acres and threatened Marine Corps Base Camp Pendleton, causing nearly 2,000 military personnel and their families to evacuate (left). Flooding at Naval Support Activity Mid-South occurred after 14 inches of rain fell in two days, costing the Navy approximately $154 million to repair the base (right). Higher air temperature dries out vegetation faster. Under drought conditions, dryer vegetation increases the risk of intense wildfires. But also, as the oceans and atmosphere become warmer, more water vapor enters the atmosphere. If more water vapor is in the atmosphere, then more water is available to become intense rainfall and produce flooding. (U.S. Navy Photos courtesy of U.S. Navy (left) and Naval Information Warfare Systems Command (right))

7. Electromagnetic and Electro-optical Systems: Climate change impacts electromagnetic and electro-optical sensors and weapons, such as RADAR and high energy lasers, by altering environmental conditions that affect performance and accuracy. Increased atmospheric temperatures and humidity can influence the propagation of electromagnetic waves, potentially degrading sensor sensitivity and range. Changes in weather patterns, such as more frequent extreme weather events and precipitation, can interfere with sensor operation and signal clarity. Extreme weather conditions and temperature fluctuations can affect the reliability and calibration of electromagnetic and electro-optical sensors and weapons, potentially impacting their effectiveness and precision. Adaptations in technology and operational strategies are necessary to maintain optimal performance in a changing climate.

8. Storms: Climate change intensifies storm activity by increasing the frequency, severity, and duration of extreme weather events. Rising global temperatures lead to warmer ocean waters, which fuel more powerful and frequent tropical storms and hurricanes, resulting in stronger winds, heavier rainfall, and higher storm surges. Shifts in atmospheric patterns can cause storms to form in regions previously less affected, and changes in weather systems can lead to more unpredictable storm paths. These enhanced storm conditions contribute to greater risks of flooding, property damage, and disruption to communities and infrastructure, which impact mission and force. Climate change also alters the occurrence of El Niño and La Niña events, which in turn affects global weather systems.

A Navy equipment operator directs disaster relief activities after Hurricane Ida hit Grand Isle, Louisiana. Working alongside civilian authorities and the Louisiana National Guard, the Navy provided critical humanitarian assistance during the disaster recovery operations. As sea level rises and hurricanes become stronger and more frequent, higher winds and more powerful storm surges create more extensive damage to coastal communities and infrastructure. (U.S. Navy Photo by Petty Officer 2nd Class Jahmai Stokes)

9. Winds and Waves: Climate change impacts winds and waves by altering their intensity and patterns. Warmer global temperatures can lead to stronger and more persistent winds due to increased atmospheric instability and shifts in pressure systems. This can result in more vigorous wave action, particularly in mid-latitudes and polar regions. Changing wind patterns can affect wave heights and frequencies, with some areas experiencing more intense and frequent storms, leading to larger and more destructive waves. These changes can influence coastal erosion, maritime navigation, the stability of offshore structures, and the effectiveness of surface ship, aviation, undersea, and amphibious operations, potentially reducing the fleet's ability to complete its missions effectively. Even reduced wind can affect how an adversary may use less interference to its advantage, such as with drone swarms.

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Point of Contact: USN Lcdr. Kellen Jones, Meteorology (ktjones1@nps.edu)