Oceans

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.

Oceans

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...

Oceans

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...

Science # Weather & Climate

Nyda’s giant ice balls

Giant ice balls covered the coast along the Gulf of Ob, an arm of the Kara Sea in north-western Siberia  a little over a week ago. The phenomenon was noticed in the small village of Nyda, which lies on the Yamal Peninsula just above the Arctic Circle. The icy spheres ranged from the size of a tennis ball to almost 3 feet across, covering 18 km of the coast. Locals in Nyda say they have never seen anything comparable in the past. However, this is not the first time this winter phenomenon...

Earth Science

Record warmest year third time in a row

NASA has declared this year to be the hottest year yet recorded. September turned out to be the warmest in modern temperature monitoring of 137 years. The recent findings follow record-breaking monthly anomalies throughout this year, leading the agency to believe that because of the highs reported so far. The first nine months of 2016, as reported by NASA, were characterized by much-warmer-than-average conditions across most of the globe's surface, resulting in the warmest January–September...

Oceans

Why are our oceans salty?

What is salinity? 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...

Oceans # Wildlife

The Olive Ridleys of Gahirmatha

Before you start presuming that we are referring to Mr. Riddle of Batman fame, let us quickly clarify that Olive Ridleys are poor green turtles, high on the endangered list, while Gahirmatha is this muddy beach beside a luxuriant patch of mangrove forest, along the coast of Odisha. Have you ever wondered about the many beautiful creatures that are lost forever in the onslaught of our ever-growing concrete jungles? Encased prettily in jars filled with liquid, creatures large and small will meaninglessly...

Weather & Climate

Measure Rainfall at Home

Monsoons are associated with mushy and wet days, loads of hot pakoras, jalebis, samosas, rainy day holidays and much more. But, apart from fun days, take advantage of-the season to do some serious research. Your results could perhaps rival that of the meteorological department! Want to take up the challenge? Read on to know what you can do. At first, you will need to measure a whole month's rainfall amount. How do you do that? Well, your school textbooks might have already listed the items, but then,...

Oceans

Seafloor Spreading

The floors of sea are not one contiguous basin. It just like the world that you see, with valleys, plateaus and mountains, except that it is all covered with water. Moreover, there are areas in the sea floor that are more 'active' than the rest. These areas are prone to faulting, fracturing, volcanic activity and spreading. Sea floor spreading is a basic premise that helps postulate the theory of plate-tectonics. The first stage in plate separation is the initiation of a new pattern of convection...