Discovery of New River in Bay of Bengal: Overview and Scientific Basis

Discovery of New River in Bay of Bengal: Overview and Scientific Basis

Question: A river has been discovered by fishermen and oceanographers across the sea on the eastern coast of the Bay of Bengal. Provide an overview of the discovery and its scientific basis.

Overview

• Fishermen and oceanographers have discovered a river in the sea meandering along the eastern coast of Bay of Bengal

• The river was discovered after the summer monsoon and it is based on decade long coastal salinity observations conducted at 8 collection points with local fishers from Paradeep to Colachel

• The movement of the mass of freshwater moves towards the end of the summer monsoon and survives for around 2.5 months

• It travels a distance of 1000 km from northern Bay of Bengal to the southern most tip of the nation

• Presence of the river was confirmed through continuous monitoring of salinity levels conducted by National Institute of Oceanography and supported by Ministry of Earth Sciences, Sorbonne University, LOCEAN La Paris and Indo-French Cell for Water Sciences

Scientific Basis

• Southwest monsoon lasts from the months of June to September in India

• During this time, water vapour collected at the surface of the ocean by the powerful southwesterly winds is flushed over the Indian subcontinent, specially the Bay of Bengal

• Massive fraction of the monsoon shower then reaches the ocean in runoff and makes a contribution to freshwater flux into the Bay of Bengal in equal proportion to rainfall over the ocean

• The three large rivers (Ganga, Brahmaputra, Irrawaddy) and three small ones (Mahanadi, Krishna and Godavari) add 1100 km of continental freshwater into the Bay of Bengal between July and September

• Intense freshwater flux into small and semi enclosed basin causes intense dilution of salt in seawater

• The close to 100 km freshwater mass formed by river discharges and runoffs is transported down south by the coastal current from East India and the western boundary current of the Bay of Bengal

• Freshwater signal lessens and occurs while progressing along the southern tip of the nation

Facts and Stats

• Salinity distribution in the Bay of Bengal will impact cyclones and regional climate in the Bay of Bengal

• Paucity of salinity data prevented thorough description of the salinity evolution earlier

• This obstacle was addressed by including fishermen in sea water sample collection process

• The occurrence of the river along the Bay of Bengal is not a generic feature found in many locations of the world, according to scientists

• Specific geographical features of the northern Indian Ocean have resulted in massive inflow of freshwater into semi enclosed northern Bay of Bengal and coastal trapped strong currents across the eastern coast of the nation were responsible for the formation of the river