Oceans # Science

Exclusive Economic Zone as opposed to Fishery Zone

According to the United Nations Convention on the Law of the Sea (UNCLOS), an international agreement in force since 1994 regarding international activity in the world’s oceans, Article 55 of the document defines the legal regime of the Exclusive Economic Zone. The article defines an area of ocean marked as an Exclusive Economic Zone (or EEZ) as – “The exclusive economic zone is an area beyond and adjacent to the territorial sea, subject to the specific legal regime established in this Part,...

Oceans # Science

Exploring Regulations to Check Saline Water Ingression in India

For people living in coastal areas rivers and lakes are not ubiquitously available. They thus depend on groundwater for their needs, which leads to probabilities of saline water ingression. Groundwater close to the coast can be easily laden with salt, especially when the equilibrium between coastal aquifers and sea water is disturbed. https://www.geographyandyou.com/climate-change/water/groundwater-sustainable-irrigation/ N.C. Mondal, V.P. Singh, V.S. Singh and V.K. Saxena in their paper titled...

Oceans # Science

Lagoons – Losing India’s rich biodiversity zones

Lagoons are generally divided into coastal lagoons and atoll lagoons. However, there is ambiguity over the distinction between an estuary and a lagoon. For this purpose the definitions given by Cameron and Pritchard (1963) are the most commonly accepted definitions. While an estuary is an inland river valley or coastal plain inundated by sea water during the Holocene sea-level rise, with tidal waves as a feature, coastal lagoons are different. Coastal lagoons have as their distinctive feature separation...

Oceans # Science

The Sargasso Sea – a unique ecosystem protected by seaweed

Located in the area marked under the fabled ‘Bermuda Triangle’, the Sargasso Sea located within the North Atlantic Ocean is the only sea in the world that does not have a land boundary. Unlike other seas, its location is defined using ocean currents. It lies within a large system of rotating ocean currents called the Northern Atlantic Subtropical Gyre. By compass directions, the Sargasso Sea’s western limit is marked by the Gulf Stream, the eastern by the Canary Current, the northern by the North...

Oceans # Science

Beneath the Ocean Floor: Discovery of Ocean Ridge

Exciting discoveries have come from an international drilling project, the Deep Sea Drilling Project. Since 1968, a drill ship, the Glomar Challenger, has drilled nearly a thousand holes into the deep ocean basins, taking samples of deep-sea sediment and crust. One early discovery suggests that the Mediterranean dried up completely between 5 and 12 million years ago, leaving thick beds of sun-baked salts as evidence buried in today’s ocean floor.


Seabed Mining

The limited opportunities to mine for minerals on land is making the world consider deep seabed mining as an alternative. But this can pose major destruction to marine biodiversity, given our limited knowledge of the effects of disturbing the high seas, especially in oxygen-minimum zones.


Climate Change Effects: An Ocean at Risk

Climate change and anthropogenic factors, are causing many marine species to die out, resulting in a devastating impact on coastal populace. Replenishing mangrove ecosystems can provide a viable solution to tackle this problem.

Environment # Oceans

Analyzing past monsoons with foraminifera

Stable oxygen isotopic composition (δ18O) of foraminifera from the sediments of the Northern Indian Ocean has been used to decipher past changes in the intensity of the South Asian Monsoon. The interpretation of planktonic foraminifera δ18O is mostly based on a combination of sea surface temperature, monsoon runoff and the global ice-volume effect. During summer, the eastward flowing summer monsoon current carries the high salinity water from the Arabian Sea to the Bay of Bengal, whereas the Bay of Bengal...


Coral Reefs in India: Status Report

The study of coral reefs have had a late beginning.  Earlier studies had accounted for only 218 species. Successive surveys made between 2008 and 2013 have reported the occurrence of 519 hard corals in India. Among the four major reefs in India, Andaman and Nicobar Islands are rich in coral as compared to the relatively poorer Gulf of Kachchh.  The isles of Lakshadweep, similarly,  have more species than the Gulf of Mannar.  Among the deepwater (ahermatypic) corals, 227 species have been reported...


Why are our oceans salty?

Why are our oceans salty? Ocean salinity, defined as the salt concentration in the seawater, is measured in unit of PSU (practical salinity unit), which is a unit based on the properties of seawater conductivity. It is equivalent to per thousand or (o/00) or to g/kg. The commonest way to record salinity is to measure the amount of salt in 1000g of water, so it is referred to as ‘parts per thousand’ or ppt. Most of the ocean has a salinity of between 34ppt and 36ppt. (www.goo.gl/4AvV6G) Global...