Oceans
23. 6. 2007
Most people of the Earth depend on the oceans.
We need them for food transport, gas and oil, or just a summer holiday.
Every year about 15,000 icebergs split from the Greenland coast. They are usually very high. The highest knot iceberg was 170 meters high which is about half the height of the Empire State Building. Most icebergs melt but sometimes they don´t so they make the sea very dangerous for ships.
It was only in 1999 that the first ship was able to follow the famous North west passage. For more than 500 years many semen like Vasco de Gama or Francis drake tried to find the way to the East around the northern coast of North America. They were not successful because the sea was always frozen. Now, thanks to global warming, the ice has got thinner, so a ship can now make the journey. During the last 30 years the temperature of the Arctic sea waters has risen by 3°C and about 40 per cent of the ice has disappeared. Scientists say that at the end of the 21 st century the Artic ice cap will not exit.