Greenland’s icebergs can’t quench the planet’s thirst

By David Fickling

Is there no end to the madcap schemes that can attach themselves to Greenland?

Thanks to President Donald Trump’s persistent interest in acquiring the Arctic island for the US, people have spent the past few weeks talking up all manner of dubious reasons why its icy wastes may conceal a veritable gold mine of resources — from rare earths, to oil, to a literal gold mine.

The latest proposal is even better. The Polar Research and Policy Initiative, a London-based think tank, told the New York Times last week that the country might have a future as an exporter of fresh water, thanks to an ice sheet that contains about 8 per cent of the total global reserves. India, Africa, and even California might become customers, Dwayne Menezes, the think tank’s director, told the paper.

The idea of towing icebergs from the poles to supply fresh water to arid countries has a long history, dating back at least to the 1950s when oceanographer John Isaacs proposed using Antarctic ice to provide California with drinking water. Despite a significant amount of diligent research over the decades, the concept has always been (if you’ll pardon the technical geo-economic jargon) bonkers.

Let’s look at the challenges involved. For one thing, you need a reliable source of unusually large bergs. Melting in the long journey toward arid latitudes is the biggest problem for any such towing operation. With blocks below about one cubic kilometer in volume it can be so rapid that less than half of the berg makes it to its destination, according to one exhaustive 1973 analysis.

Such massive chunks are relatively rare, particularly in the Arctic. The vast Antarctic ice sheet regularly break off huge and flat “tabular” bergs surrounded by high cliffs, which were reckoned to be most suitable for towing. Arctic icebergs like those in Greenland tend to be smaller and irregular, making them more vulnerable both to melting, fracturing, and to flipping over with the force of a nuclear bomb — something anyone planning to crew or insure a towing fleet might want to consider before setting out.

Some studies suggested encasing entire bergs in insulation to reduce the rate of ice loss, but no one came up with a serious proposal for how you would go about creating this Christo and Jeanne-Claude-style piece of industrial land art on anything like a sufficient scale.

Surprisingly, the actual towing effort may be the easiest part. Tugboats are astonishingly powerful and can move vessels many times their own size with ease. Ocean currents can assist, too. The 1973 study concluded that plenty of ships even then had sufficient power to get a berg from the Antarctic to northern Chile or southern Australia.

The final problem comes when you get to port. Or not port, exactly: Most viable bergs would extend far too deep below the water line to get anywhere close to shore. You’re then in a race against time to extract the water before it melts altogether. Various proposals involve strip-mining the berg, or surrounding it with a floating boom and hoping the less-dense fresh water will float on top of seawater long enough to be pumped ashore.

Either way, your once-pristine polar water will now be heavily polluted from engine fumes, and require processing. And still the problem remains of where to store a cubic kilometer or so of water until it’s ready to be used, especially in an arid region with intense evaporation.

If we had no alternative to provide the parched corners of the earth with sufficient water, it might still be necessary to carry out these heroic feats of engineering — but that’s not the case. Already in the 1970s, during the heyday of iceberg-towing proposals, the likes of Kuwait were pioneering desalination technology for drinking water, while Hong Kong was separating the fresh and salt-pipe systems so that people could flush their toilets with seawater.

The former innovation turned out to be the world-changer: There are now 21,000 water desalination plants worldwide, providing about 99 billion liters a day — sufficient to supply fresh water to between one and two billion people at levels the United Nations considers a minimum.

Usage of the technology is heavily skewed toward rich, arid countries in the Middle East, to be sure, but the price of desalination has fallen rapidly in recent years, especially as solar power has pushed down the cost of energy, the biggest input. Most places can produce drinking water now for a 10th of a cent or less per liter, putting it well within the reach of even the poorest countries.

India’s perpetually water-stressed city of Chennai has four desalination plants operating and under construction. Egypt, barely more wealthy than many nations in sub-Saharan Africa, has 90 such facilities up and running.

Greenland’s military significance is hard to gainsay, but whatever commodity you think of, you can’t argue it’s a resource hub. If it’s not going to be a worthwhile supplier of oil or rare earths, it’s certainly not going to provide the world with icebergs full of fresh water.