A study published by the NATO Defense College, March 2025
The publication explores how climate change is altering the strategic landscape of submarine and anti-submarine operations. Traditionally, security scholars have focused on climate change’s role in civil conflicts, migration, and instability. However, NATO has recently begun to recognize it as a significant threat multiplier that affects global security, particularly in underwater warfare.
The authors argue that climate change directly impacts sonar detection, which is the primary tool for anti-submarine warfare. Sound propagation in water is influenced by temperature, salinity, and depth. Rising sea temperatures and Arctic ice melt are altering these factors, consequently affecting sonar performance. Through oceanic acoustic simulations comparing historical (1970–1999) and projected future conditions (2070–2099), the study finds that detection ranges for submarines will shrink in most areas, particularly in the North Atlantic. This reduced visibility could be exploited by adversaries like Russia and China, allowing them to operate more effectively in regions where NATO’s capabilities are compromised.
The findings carry significant strategic implications. If submarine detection becomes increasingly difficult in the North Atlantic, adversaries may use this to divert NATO’s resources from other key areas such as the Indo-Pacific. Russia has already increased its submarine activity in the Atlantic, while China has made efforts to access the region via the Arctic. The study suggests NATO should reconsider its strategic focus and reinforce its presence in the North Atlantic.
Additionally, the research challenges claims that submarines are becoming obsolete due to advancements in sensing technology. While some argue that new surveillance methods will neutralize submarines’ stealth advantage, the study suggests the opposite—climate change may enhance submarines’ ability to evade detection. This underscores the continued strategic importance of submarines, both for deterrence and for offensive operations, including land strikes.
Beyond strategy, the study highlights the urgent need for military adaptation. Climate change is reshaping battlefield conditions, necessitating adjustments in technology, tactics, and operational planning. Future naval forces must integrate new technologies like unmanned underwater vehicles (UUVs) to counteract evolving threats.
The paper concludes that climate change is not merely an environmental issue but a core defense challenge. It calls for further interdisciplinary research and war games that incorporate climate impacts into military strategy, ensuring that NATO and other actors remain prepared for the shifting dynamics of underwater warfare.
This article is based on the extracts from the research study written by Andrea Gilli and Mauro Gilli, March 2025. To read the full paper use the link here.
See below for our coverage on similar topics:
- Irish Defence Forces Review 2024: Climate Change, Security and Defence
- Earth System Tipping Points Are a Threat to Europe – How to Get Prepared?
- Shaping the Future: Energy Transition in the Defence Sector