“The eternal silence of the infinite space frightens me.” This statement by 17th century mathematician Blaise Pascal sums up nicely the immense possibilities that the vast expanse of oceans offer.
The oceans cover around two-third of the earth’s crust and help sustain life on the earth.
It is home to more than 80 per cent of the animals on the earth. It has 26 of the 28 animal phyla, 30,000 algae and millions of micro-organisms.
With more than 50 per cent of the people across the globe living within 100 km from the coasts, oceans and seas are also sources of food.
A tiny change in a remote corner of the Pacific Ocean can send its ripples to as far as the Indian Ocean. It’s a binding force across the globe.
Oceans are from where the copious monsoon winds begin to blow. The sun's heat evaporates water on the surface and as the warm winds blow on one side, there is a cooling of the waters on the other side.
The winds blow from the high pressure areas to the low pressure ones and condensation there causes rain.
The threshold degree level is 27.5 degrees Celsius where through the feedback mechanism the atmosphere begins to cool after getting heated. In the Indian Ocean the threshold level is 23.5 degrees, say scientists. And there is a level of unpredictability in the ways of the waters.
Even while staying firm on the land and talking about global warming, it has to be realised that the umpteen planktons and weeds and plants in the ocean take in large amounts of the carbon dioxide that are added to the waters by the insensitiveness of mankind through dumping of toxic waste into the waters or littering plastics.
The 70-80 per cent of the plants in the waters help to check to a small extent this by reducing carbon levels, says P.M. Muraleedharan, scientist at the national Institute of Oceanography.
Advancements in science and technology, including scuba diving, help in uncovering the treasures the down deep below.
But all’s not calm on these waters. Unless people realise that life on this earth is sustained by the oceans that are sources for food and medicines and the rains and are not to be turned into dumpyards, the clouds on the horizon portend disaster, say scientists.
Blue expanse turns into deadly cocktail
The blue beauty is dying a slow death. The truth that lies in the abyss of our oceans belies the magnificence of her romantic embrace that satellite cameras transmit.
Churning beneath the blue surface is the dark reality of a highly contaminated ocean system. Ocean water, today, is a deadly cocktail of plastic and toxic waste, marine debris and chemical residue.
“Plastic is the biggest threat. Deep sea trawlers find their nets full of plastic waste. Sorting their catch from this waste is itself becoming a huge task for them,” points out Dr N.G.K. Pillai, Emirates Scientist, Central Marine Fisheries Research Institute.
Plastic waste deposits are found at varying depths; from continental slope to shelf.
“About 50 percent of the beaches are destroyed due to sea erosion, dumping of wastes including plastics and other industrial wastes. Human interference is making marine ecosystems such as corals, mangroves and sea grass ecosystem highly vulnerable,” he says.
According to experts, acidity in oceanic ambience is also on the rise. Greenhouse emissions impact oceans too.
Huge quantity of carbon dioxide is getting mixed with oceanic waters. They eventually lose their alkaline character. This is not good for sealife, Pillai points out.
“Sea surface temperature is also increasing. This results in coral bleaching and destruction to other oceanic flora,” he says.
Migration of alien species to our waters also poses a major threat. This affects an endemic ecosystem. Many invasive species are introduced through ballast water and ships' passage.
“Tankers pump in huge tonnage of water to maintain ballast after unloading cargo. It is pumped out at the next port before loading freight. As a result all pollutants, including biological species, find their way to alien waters,” Pillai says.
0 comments:
Post a Comment