|
Jelly Fish
Increase of polution and global warming changes the living of jelly fish and other species in it´s ecosystem. Changes to pH level, temperature will affect animal populations and growth of food. Jelly fish will then have to adapt to the new changes, most will not survive in time as their are less food and hospitable homes for it to reside.
The explosion of jellyfish populations, scientists say, reflects a combination of severe overfishing of natural predators, like tuna, sharks and swordfish; rising sea temperatures caused in part by global warming; and pollution that has depleted oxygen levels in coastal shallows.
These problems are pronounced in the Mediterranean, a sea bounded by more than a dozen countries that rely on it for business and pleasure. Left unchecked in the Mediterranean and elsewhere, these problems could make the swarms of jellyfish menacing coastlines a grim vision of seas to come.
http://blogfishx.blogspot.com/2008/08/jellyfish-and-ocean-decline.html
The Bosphorus is by no means an easy passageway
It is the only outlet of the Black Sea, an inland sea of relatively low salt content near the surface because of the inflow of three large rivers-the Danube, the Dnieper, and the Don. Without evaporation or outflow through the Bosphorus, fresh water from these rivers would raise the level of the Black Sea about thirty centimeters a year. The salt content at the surface, and thus the content of the Bosphorus, is 1.8%. The lighter fresh water floats on the surface of the heavier salt water at the depths. As the fresh water flows out through the Bosphorus, it carries salt water with it. This decreases the amount of the heavier salt water at lower depths and causes salt water to be drawn from the Aegean Sea via the Marmara to restore the balance. Thus between 45 meters and 15 meters below the southward current of warmer and fresher water in the Bosphorus is a northward current of colder and saltier water from the Mediterranean.
The volume of water in the southward current is about two and a half times greater than that of the northward current. This intermingling of currents explains the extraordinary turbulence of the Bosphorus. It is a notoriously dangerous body of water, despite its, calm appearance. The surface current is between one and five knots (two to ten km/hour), depending on the wind , width, and depth of the channel, and obstructing promontories, but it has been clocked at seven knots at Kandilli Point, earning it the appellation “Devil’s Current.”
Orhan Pamuk’s memoir of Istanbul devotes several pages to the menace of those passing ships, and it’s something you find yourself thinking about now and then. The rocky shores of the straits are, now, mercifully still, but the Bosphorus is by no means an easy passageway. While a two foot drop in levels between the Black Sea and the Sea of Marmara creates a surface current running from north to south, another, deeper current moving upwards from the Mediterranean scours the bottom of the strait. The indented shoreline makes for vicious counter-currents on the surface, too. Seventy years ago, in 1936, when the Straits were thrown open to all shipping, Istanbul had a population of half a million, and 17 ships passed every day. Now it has twelve million, and almost 5000 ships slide through it every month, Ukrainian ferries, Russian and Bulgarian container ships, Italian cruise liners, and an uncomfortable number of oil and gas tankers from the Black Sea.
|
i had a feling it didnt make sense!9this would be soo embarasing if it turned out to be true!!)