Who is doing what?

A firm in Abu Dhabi has floated plans to tow icebergs from Antarctica to the United Arab Emirates to solve the country’s fresh water shortage. An iceberg holding 20bn gallons of fresh water could meet the needs of a million people for five years, but first it would have to be hauled across 10,000km of open ocean to the coast of Fujairah, a feat that could take a year. In a promotional animation released by the firm, a giant, flat-topped iceberg is towed into the Persian Gulf bearing penguins and polar bears, which double as a tourist attraction. There are no polar bears in Antarctica.

How bad is the water shortage problem?

The pace of development in UAE is such that groundwater supplies are predicted to run dry in the next 15 years. A typical Emirati uses 500 litres of water per day, about 80% more than the global average. Dozens of desalination plants provide nearly all of the country’s drinking water, but the plants are expensive and require huge amounts of electricity to strip the salt from seawater. Globally, the UN warns that within two decades, 600 million children will live in regions enduring extreme water scarcity.

Have icebergs been towed from Antarctica before?

No one has towed icebergs from Antarctica to provide water to parched nations, but the idea is far from new. In the early 19th century, proposals to tow icebergs into the Southern Ocean to balance out the temperature of the Earth were already considered old hat. But enthusiasm for the challenge persisted. In 1863, one US entrepreneur proposed towing icebergs to India, where they would sell for six cents per pound. Another planned to do away with tugboats altogether, and effectively turn the icebergs into ships themselves.

Is it possible to tow an iceberg?

The Canadian oil and gas industry regularly tows icebergs away from offshore platforms when there is a risk of collision. But by Antarctic standards, these icebergs tend to be smaller ones, and they are not towed that far. On average, these icebergs are 60-80 metres wide at the waterline, weighing around 100,000 tonnes, said Tony King, director of ice engineering at C-Core, a Canadian engineering firm that makes equipment for the job. Larger icebergs weighing up to 1m tonnes have reportedly been towed with a rope slung between two vessels. Typically, icebergs are towed for a few dozen kilometres to get them out the way of oil and gas platforms sitting a few hundred kilometres offshore.

Could an iceberg be towed to UAE?

According to Grant Bigg, professor of Earth systems at Sheffield University and author of the 2015 book Icebergs, there is a long list of technical hurdles that must be overcome. Synthetic fibre ropes, which are stronger than steel, can be slung around icebergs at the waterline, but when tugging begins the rope can slip off or make the iceberg roll over. Another reason the towing must be done slowly and carefully is that dragging an iceberg through the ocean can make it break apart. The industry has come up with nets for capturing unstable icebergs, but they don’t work in every case. “There are two major problems,” said Bigg. “One is getting a vessel that’s strong enough to tow the size of iceberg you need. The second is breakup and melting. It would probably be feasible to get an iceberg a kilometre or two wide up to the Arabian sea, but you’d lose an awful lot of mass on the way. It’s quite likely it would fracture before you got there.”

And then there is the cost. A single iceberg-towing vessel can cost around $75,000 a day, and to tow a massive iceberg might need several ships for months at a time. “It comes down to the question of what is feasible and what is practical,” said King. “Is it more practical to take a tanker to Antarctica and capture some fresh water melting off a glacier?” In Canada, shops already sell bottled water made from chunks of frozen water that are chipped off icebergs. King has a chunk in his freezer. “It makes for nice ice,” he said. “It makes a nice crackly sound in a glass of water.”

In principle, were an iceberg to be anchored off the coast of UAE, the freshwater that melts off would float on top of the salty seawater, and could then be drawn off to use. But the release of so much cold, fresh water into the sea, along with damage caused to the seabed from grounding the iceberg, could be devastating to the local marine ecosystem.

What are the alternatives?

There is no magic-bullet solution. Farming is a major driver of water scarcity, with vast quantities used in hot countries to irrigate crops and to water cattle to cater for diets that are increasingly rich in meat. Beyond changing people’s diets and ensuring that agriculture and other sectors use water in more sustainable ways, there are large-scale technologies to reprocess wastewater, filter contaminated supplies and make desalination plants more efficient and less environmentally damaging.