Deep Sea Research and Management Needs

The deep sea plays a crucial role in the global health of the Ocean and the planet as a whole. We all benefit from the deep ocean. It encompasses 90% of total Ocean volume, provides essential ecosystem services and functions, and hosts diverse ecosystems with potentially millions of (mostly unknown) species. Yet, essential ecosystem services including nutrient cycling, carbon sequestration and support for marine biodiversity are under threat. The Ocean absorbs 90% of excess global heat and a quarter of excess carbon dioxide, serving as a buffer against climate change, but by doing this it is also putting deep-sea ecosystems under pressure due to warming, acidification, and deoxygenation. On top, activities in the deep sea such as oil and gas extraction, fishing, and potential new activities like mining and marine carbon dioxide removal may lead to habitat destruction, biodiversity loss, and disruption of critical ecosystem functions and services. Despite the importance of this biome, deep-sea research is hindered by logistical and financial constraints, creating significant knowledge gaps. Understanding baseline conditions and the impacts of human activities in the deep sea is essential for sustainable management and informed decision-making. The UN Ocean Decade underscores the urgency of these efforts.

In 2023, the European Marine Board established a working group to produce a comprehensive report on the current state of the deep sea, identifying knowledge gaps and providing recommendations for policymakers, funders, researchers, and global capacity-building initiatives to support sustainable management. Here an overview will be given of the key challenges the deep sea currently faces and strategies to address them, as detailed in the EMB Future Science Brief 12 published early 2025.