Water as a topic within the framework of Global Warming is a good topic. Desalination can of course provide fresh water, but you can't build enough to offset the decline IMO so I would still be concerned, but it can be kicked down the road to be someone else's problem. There’s no magic fix. Desalination is a poor solution—it’s expensive and energy-intensive and produces more chemical-laced brine than potable water. Much of that brine, which is extra-salty and contains potentially harmful substances necessary for the desalination process, including copper and chlorine, is pumped back into the ocean. There, its density causes it to sink to the ocean floor, where it depletes oxygen and destroys marine life. According to a 2019 UN report, global desalination plants already produce 51.8 billion cubic meters of brine annually, enough to cover the entire state of Florida a foot deep. Last year a study of almost 180,000 people in Israel linked desalinated water to a 6% to 10% increase in heart disease.
I was involved in putting a cost benefit exercise together for a ME Country, which involved analyzing bringing icebergs towed to the country to meet fresh water needs versus desal plants. My first thought was these people are crazy, but when the analysis was complete it was definitely feasible and an option, the fact it had never been done before and cost meant it never happened, perhaps one that will be used in the future by some countries.
https://www.youtube.com/watch?v=xCnZ1F9RAJo
Water is as important to the world’s economy as oil or data. Though most of the planet is covered in water, more than 97 percent of it is salt water. Fresh water accounts for the rest, although most of it is frozen in glaciers,
leaving less than 1 percent of the world’s water available to support human and ecological processes. Every year, we withdraw 4.3 trillion cubic meters of fresh water from the planet’s water basins. We use it in agriculture (which accounts for 70 percent of the withdrawals), industry (19 percent), and households (11 percent). These percentages vary widely across the globe. In the United States, industrial usage (37 percent) is almost as high as agricultural (40 percent); in India, on the other hand, agriculture claims 90 percent of water withdrawals, while only 2 percent is put to work for industry. China’s withdrawals are 65 percent agriculture, 22 percent industrial, and 13 percent for household use. Considering that some of the agricultural usage is directed toward industry—for example, half of the production of maize, which is one of the top five global crops by total acreage and water consumption, is used for producing ethanol—the figures may understate how critical water is to business.
The availability of fresh water also varies greatly by location. The majority of the world’s fresh water is divided among 410 named basins, which are areas of land where all water that falls or flows through that region ultimately ends at a single source. These include the Huang He, Nile, Colorado River, Indus, and many others. Of these 410 named basins, almost a quarter (90) are considered “high stressed” (meaning that their ratio of total annual withdrawals to total available annual supply exceeds 40 percent). These 90 highly stressed basins account for just 13 percent of the total area of named water basins but account for 51 percent of withdrawals (Exhibit 1). About half are located in three countries with enormous water needs and high economic activity: China, India, and the United States.
Water risk is not a worry to be addressed in some nebulous future. The supply of fresh water has been steadily decreasing while demand has been steadily rising. In the 20th century, the world’s population quadrupled—but water use increased sixfold.