March 1, 1996. Copyright, 1996, Graphic News. All rights reserved

ALL STEAM AHEAD IN THE RACE TO THE OCEAN FLOOR
By Nicholas Booth, Science Editor

LONDON, March 1, Graphic News Ð Until recently, it was the claim of the ocean scientist that we knew the surface of the Moon better than we knew the oceans of the Earth. But now, thanks to a new generation of ships, sensors and satellites, many of the mysteries of the deep are being addressed and solved. In Brighton this week (March 5-8), around 6,000 of the worldÕs leading oceanographers meet to discuss their latest findings. Their conference comes as ocean explorers Ð both human and robotic Ð prepare to explore the deepest regions of the sea bed.

Nearly three-quarters of the worldÕs surface is covered by oceans, the vast bulk of which Ð an estimated 80 per cent Ð are more than a mile deep (1.5km), whilst the deepest trench reaches a depth of over 11,000 metres. The oceans play a fundamental role in driving our climate. They act as a giant heat pump Ð containing nearly 1,400 million cubic kilometres of water Ð powered by a billion megawatts of energy from the action of sunlight. The oceans also fix carbon dioxide levels by removing CO2 from the atmosphere before it builds up to accelerate global warming.

But scientific interest is now focused on the seabed. The ocean floors contain the seams of the plate tectonics upon which the EarthÕs geology is effectively driven. The discovery of river channels in the sea floor plus sub-oceanic landslides and volcanoes hold clues to the way in which those seams sometimes fall apart. A worldwide programme known as the Ocean Drilling Program is investigating these missing links in our understanding by drilling deep below the ocean bed. Geologists hope to learn just how large are important mineral reserves found there, such as nickel, iron, manganese and copper. 

Physically reaching the ocean floor is problematic. Most ocean exploration takes place in shallower waters above 600 metres but now a new generation of submersible vehicles is under construction. The technical difficulties are fearsome, for the pressure is crushing and temperatures reach very close to freezing point. There are two approaches to the problem: automated underwater vehicles carrying video images along fibre-optic cables, as pioneered by the Japanese ÔKaikoÕ vehicle which last year explored the Mariana Trench, while later this month Graham Hawkes, a British-born explorer, will attempt to reach Challenger Deep, the deepest part of the trench, in Deep Flight 1, seen as a prototype for routine deep ocean exploration by humans.

Of all the curious vistas to be found on the seabed, the most unusual are lifeforms which have adapted in remarkable ways to the absence of sunlight needed to generate photosynthesis. Most species found here are sluggish, do not have skeletal frames and have developed along totally different evolutionary lines to fauna on land. Most remarkable of all are tube-like worms, roughly 20 centimetres in length, found living around thermal vents in the ocean floor. These worms feed on bacteria that gain their energy from hydrogen sulphide, normally poisonous to most lifeforms. Biologists are excited by the other species that lie, unsuspected along the ocean floor, awaiting discovery.

Sources: National Environment Research Council, Spearhead Exhibitions Limited, Southampton Oceanography Centre.

EDITORÕS NOTE: Oceanology International 1996 is being held at the Metropole Hotel, Brighton. For further information, contact the press office (01273) 325281 where Judith Patten will be delighted to help with your enquiries.