SARGASSO Sea in Trouble:Why US should worry
THE SARGASSO Sea is warmer, saltier, bluer, and clearer than most other parts of the North Atlantic.It plays important role in trans-atlantic trade between North America and Europe.But geographically its open waters were mostly desert-like, unproductive regions populated by a few smaller plant species.
It has vast
blooms of microscopic plants called Sargasso formed in the middle of otherwise barren mid-ocean regions.
It has been observed by Woods Hole Oceanographic Institution (WHOI) that its episodic, swirling current systems known as
eddies act to pump nutrients up from the
deep ocean to fuel such phytoplankton blooms. Its biological activity was surprisingly high when the ocean was stirred by certain types of eddies.
Reserches indicates that its oxygen and other biologically important elements being consumed at a
higher rate than the theories and models could account for. There had to be some natural nutrient source.Its eddy-driven nutrient transport actually primes the ocean's "biological pump," fertilizing the waters with nutrients from the deep.
Due to this unusual upwelling, the phytoplankton population explodes and, in turn, attracts more zooplankton and other animals higher up the food chain. The fate of all of that biomass is also important, as plankton blooms can remove substantial amounts of carbon dioxide from surface waters and sink it to the deep ocean.The eddies are formed by differences in ocean temperature and salinity that give water different densities.The density inside an
eddy can be higher or lower than the surrounding water, like high and low-pressure systems in the atmosphere. The balance between density and pressure differences, along with earth's rotation and due to corriolis force gives eddy currents their distinctive clockwise or counterclockwise spin. The direction of the spin depends on whether the eddy contains cooler "mode water" or a warmer core.
swirling currents of water can perturb the layers of the ocean and cause an upwelling of nutrient-rich water into the sunlit "euphotic" zone— the top 330 feet (100 metres) that light penetrates.
NASA satellites are measuring sea surface height to locate eddies in the Sargasso Sea, south and east of the Gulf Stream in the North
Atlantic to achnoledge the danders in navigation and also to understand its impact on marine life.
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