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Submarine groundwater discharge schematic

Detailed Description

Submarine groundwater discharge (SGD) is an ubiquitous coastal process that is driven by a composite of climatologic, hydrogeologic, and oceanographic processes. For example, terrestrial hydraulic gradients that reflect both short- and long-term climatic conditions almost always transport both surface and ground water toward the coast. In coastal waters, physical oceanographic processes such as wave set-up, tidal pumping, and density-driven circulation impact these hydraulic gradients and thus affect rates of submarine groundwater discharge. Although only fresh groundwater discharge has traditionally been accounted for in numerical simulations of coastal water budgets, the discharge of recirculated saline groundwater may be equally or even more important in terms of material transport (for example, nutrients, metals, organics) across land/sea margins. We therefore define SGD to consist either of fresh groundwater, re-circulated seawater, or a composite therefore, and evaluate and present SGD in terms of a vector for nutrient delivery to coastal waters.