LONDON (Reuters) - Fleets of supertankers could one day ply the world’s oceans laden not with oil but fresh water.
In Paris on Friday the world’s top climate scientists issued the strongest warning yet that human activity was heating the planet. They forecast temperatures would rise by between 1.1 and 6.4 degrees Celsius this century.
By 2100, water scarcity could impact between 1.1 and 3.2 billion people, says a leaked, related U.N. climate study due to be published in April.
China and Australia, as well as parts of Europe and the United States would face critical water shortages, it says.
Maritime experts say shipping water by tanker is one of the least eccentric ideas raised of late to counter acute shortages.
Dragging icebergs from the Arctic, ships hauling enormous bags of fresh water, and cloud seeding — in which clouds are sprayed with chemicals to induce rain — have all been aired by water authorities in the past.
“You can ship any liquid commodity if the money’s right,” said Bill Box, spokesman for Intertanko, the world’s largest association of tanker owners.
Tankers would need to be specially coated for the water trade or built as a dedicated fleet.
In 1996, the World Bank’s then water resources manager, John Hayward, said: “One way or another, water will be moved around the world as is oil now.”
Daniel Zimmer, executive director of the World Water Council in Marseille, said there was a real prospect that fleets of dedicated tankers could shuttle fresh water between countries.
But he saw it only being feasible for essential supplies of fresh drinking water and not for low grade agricultural water where the cost of freight would outweigh the benefits.
“We definitely see it increasing. We expect in the future and even in the short-term, before 2050, more frequent heatwaves and dry periods which could make shipping water economically justifiable,” he told Reuters.
He said exporting water by sea was already happening between France and Algeria and Turkey and Israel.
He said countries with abundant water supplies like Norway, Russia and New Zealand could also begin to ship water more regularly.
“You could imagine countries north of the Mediterranean sea shipping fresh water to the south, the dry areas,” Zimmer said.
Some water firms are already taking the prospect of shipping water seriously — last May, London’s Thames Water investigated bringing water supplies by tanker from Scotland and Norway to solve emergency shortages due to drought.
Thames Water’s Richard Aylard told the Times newspaper that alternatives had included towing icebergs from the Arctic and seeding rain clouds.
At the end of last year New Zealand firm Adsteam Agency proposed taking water by tanker to Australia when that country was suffering its worst recorded drought, shipping experts say.
In Australia, a firm called Solar Sailor is developing electric-hybrid supertankers powered by solar sails to carry water, according to its Web site.
The chairman of Solar Sailor, former Australian prime minister Bob Hawke, has said the concept could solve Sydney’s water crisis.
Some question whether shipping supplies from countries rich in fresh water would provide a long-term answer.
“Tankers have been used to transport water in the past between islands, in places like the West Indies, but the issue here for the future is one of scale,” said Peter Hinchliffe of the International Chamber of Shipping.
“A supertanker full of oil can supply a city far longer than one full of water,” he said.
For existing oil tanker owners the international shipping of water could hold an unexpected silver lining.
Responding to a series of high-profile oil tanker disasters the U.N. International Maritime Organization in 2003 accelerated a time-table to retire single-hulled oil tankers.
The final deadline for their elimination is 2015. But such pollution issues wouldn’t apply if they were carrying water.
“Maybe this is great news for the phase out of aging single-hulled tankers between 2010-2015,” said Intertanko’s Box.
“If anyone is serious about transporting water in tankers then they should be looking at single-hulled tankers because there will never be a cheaper source of ship,” Box said.