One in four people on Earth face shortages of water for drinking, sanitation, agriculture and economic development. Water scarcity is expected to intensify in regions like the Middle East and North Africa region, which has 6% of the global population but only 1% of the world’s freshwater resources.

Conventional water sources – which rely on snowfall, rainfall and rivers – are not enough to meet growing freshwater demand in water-scarce areas.

Fortunately Earth has other sources of water: millions of cubic kilometres of water in aquifers, in fog and icebergs, in the ballast holds of thousands of ships, and elsewhere.