The Integrated Marine Biosphere Research (IMBeR) is pleased to announce the launch of a new endorsed working group: the Submarine Groundwater Discharge Working Group (SGD-WG). Co-chaired by Dr. Bochao Xu (Ocean University of China) and Prof. Isaac Santos (University of Gothenburg), this international network of 33 scientists from 9 countries is dedicated to investigating one of the ocean’s most critical and overlooked processes—Submarine Groundwater Discharge (SGD)—and its cascading impacts on global biogeochemical cycles, ecosystem function, and climate resilience.
SGD refers to any flow of water on continental margins from the seabed to the coastal ocean—ranging from fresh to saline. While largely invisible to the eye and absent from traditional observing systems, these subsurface fluxes transport substantial quantities of nutrients, carbon, trace metals, and greenhouse gases from land to sea. In many coastal systems, SGD-derived nutrient inputs surpass those from rivers. Yet despite its magnitude, SGD remains largely excluded from global nutrient budgets, Earth system models, and ocean governance frameworks.
The SGD-WG aims to change this by establishing a global, interdisciplinary platform for detecting, quantifying, and interpreting SGD across varied geophysical and ecological settings. Drawing expertise from hydrology, oceanography, biogeochemistry, coastal ecology, and environmental policy, the group will address critical knowledge gaps through coordinated efforts in the following priority areas:
(1) A reflection of the benefits and challenges of the existing SGD definition and related language
(2) establish standardized protocols for SGD detection and quantification, set up long-term SGD monitoring stations/networks worldwide
(3) estimate SGD flux in global continental margins and elucidate its ecological response (e.g., eutrophication, carbon outwelling, and coastal habitat health) in diverse ecosystems
(4) incorporating SGD into international marine management frameworks and water quality regulations
The SGD-WG supports IMBeR’s broader mission of advancing interdisciplinary marine research to foster sustainable ocean–biosphere interactions and translate science into actionable policy. Submarine groundwater may move slowly and unseen, but its effects are anything but negligible. The mission of SGD-WG is to ensure that this hidden circulation becomes fully visible—scientifically mapped, operationally monitored, and institutionally recognized.
For more information:
Visit the SGD-WG homepage: https://imber.info/science/regional-programmes-working-groups/sgd-wg/