4SEAS

If you look at the Earth from space, what you see is that the sea is in fact, the largest and most important feature of our planet. The sea covers almost 71% of the Earth’s surface, approximately 361 million square kilometres (139 million square miles). The Sea contains 97% of all the water on the planet and by volume it is the single largest habitat for life on Earth. Although most coastal seas are rather shallow (less than 200 m deep), because of the great size of the deep ocean basins, the average depth of the sea is around 3800 m. If we do the same calculation for the land, we find that the average height is only 840 m. The deepest place in the sea is the Mariana Trench which is 11033 m deep (6.8 miles), which is over two kilometeres deeper than Mount Everest is in height (8848 m).