Understanding Submarine Groundwater Discharge (SGD) and its Importance in the Nearshore Science is Essential? A Discussion

1. Existing studies suggested that there was some unexplained oceanographic process that happened in the nearshore regions.

2. Identification of some Submarine Ground Water Discharge (SGD) in and around study regions suggested that the above unexplained process may have a link with this process.

3. Suggested a combined oceanographic and hydrogeologic study essential to understand the nearshore marine environment process.

The ground water moves into the seawater and mixes with the nearshore marine water due to its hydrological gradient is designated as a Submarine Ground Water Discharge (SGD). Reports from Hawaii west coast and Yucatan Peninsula suggested that all the freshwater entering into the sea as SGD. These flows (SGD) occur as spring and diffuse flow, through the continental shelf regions. The quantum of this mechanism was not understood properly. Similarly, the Andaman Islands also exhibit SGD since predominant volcanic out crop does not provide ample scope for the copious tropical torrential rainfall (3394mm/y) to perculate down and most of it divulges into the nearshore as SGD either through diffuse flow in many places or through springs in few places. The paucity of study from the area under the present investigation concerning SGD, leads to an attempt to understand the dynamics and impacts on the nearshore oceanographic process due to SGD. The existing literature also supports this factor. A submarine spring was also identified nearby island makes this concept more valid. However, an authenticated study, exclusively need for combination of groundwater and nearshore parameters may really reveal the factors, what’s is exactly happening in the nearshore environment, which may reverse the paradigm of nearshore eco-biological inferences.

Keywords: Submarine groundwater discharge; SGD; Islands; Andaman; India