In a warming world, freshwater production is moving deep beneath the sea

Some four miles off the Southern California coast, a company is betting it can solve one of desalination’s biggest problems by moving the technology deep below the ocean’s surface. OceanWell’s planned Water Farm 1 would use natural ocean pressure to power reverse osmosis — a process that forces seawater through membranes to filter out salt and impurities — and produce up to 60 million gallons (nearly 225 million liters) of freshwater daily. Desalination is energy intensive, with plants worldwide producing between 500 and 850 million tons of carbon emissions annually — approaching the roughly 880 million tons emitted by the entire global aviation industry.