The rainfall in the American West is highly dependent on surface temperatures of the Pacific Ocean. There is more rainfall in the American west during El Niño years and less during La Niña years. The two ocean temperatures oscillate with El Niño dominating some decades and La Niña other decades.
Periodically...every ten-to-fifteen decades or so, La Niña dominates and we experience a mega-drought. We had a mega-drought in the 1930s, 1855-1865 and tree rings inform us that we had western "mega-droughts" 1265-1300, 1125-1160, 975-1010, 810-840.
What is notable about this medieval series of droughts is that they were all approximately three decades long and had approximately 100 good years between the end of one and the start of the next. The interval between the last two mega-droughts was only 65 years.
Approximately 7 million people lived in California in 1940. At that time, very little water was used by humans for amenities like lawns, golf courses, swimming pools, car washes...or flush toilets. Today there are approximately 40 million people living in California today and the per-capita water use is estimated at 100 gallons per day for non-industrial, non-ag uses.
Things might get sporty when the next La Niña dominance cycle starts.
It has been postulated by many bright minds that one of the resources the next world-war may be fought over, is potable water.
ReplyDeleteThe technology is there to make potable water out of seawater, I wonder if that costs less than putting on a war?
DeleteThe technology exists, but the purists on the CA Coastal Commission will deny any permits required because of potential harm to sea life. They denied permits for a plant for Santa Barbara decades ago and recently denied permits for a plant in Huntington Beach that would use the seawater piping previously installed for a power plant. The plant was a steam plant with seawater cooling and is now a gas turbine combined cycle plant with air cooling.
DeleteI thought the Huntington beach plant was in use. It supplies water to the Newport Elites.
DeleteThere wasn't a desalination plant there when we left in 2022, but Mesa Water runs a reverse osmosis facility to make groundwater with really high levels of organics (enough to be brown) usable as tap water. The concentrate from the RO facility goes to the local sanitation plant for dilution by the waste stream before getting discharged into the ocean.
Deletehttps://www.mesawater.org/about-us/operations/mesa-water-reliability-facility?highlight=WyJtd3JmIiwibXdyZidzIl0%3D
ERJ - It is a real consideration for which many states and municipalities are simply whistling past the graveyard, hoping it does not hit on their watch. The fact that historical this areas were low density populations that now have hundreds of thousands or millions of people should not go unnoticed.
ReplyDeleteI think I recall there being some speculation as to this contributing to the disappearance of the cliff-dwellers in the southwest.
ReplyDeleteDesalination is a big thing in a lot of areas such as UAE or the Canary Isles. Modern plants only need about 3 kWh of power to produce 1000 litres of drinkable water. In my experience it is a bit of an acquired taste, because it is never really salt-free. You really have to pay attention to the unnecessary use of the water if you have to go down this route.
ReplyDeleteThe RO concentrate goes into the waste line because the system uses the pressure difference to drive the process. The waste water is what it was now (RO drinking water + RO concentrate = input water), and the RO unit really only runs when you are pulling from that tap.
DeleteMy under-sink unit can’t make it that fast and fills a bladder tank which takes about an hour to make a gallon. The unit advertises 25 gallons per day. Our water in Las Vegas is very high in Calcium and Magnesium and other stuff. So after I fill a coffee pot of water it may take 20 minutes to refill.
DeleteI'm not surprised at that rate, 40-50 psi differential pressure isn't enough energy to produce water faster.
DeleteI remember reading in either"Oaks of California," BM Pavlik or a book on "Missions of California" where a Catholic missionary had written that he traveled the mission trail from Baja to San Francisco area " without ever leaving the shade of oaks".
ReplyDeleteThat certainly wouldn't be the norm today. Possibly draughts are historic and intensified by our removing of trees.
I heard recently of the idea of using difference in the weight of a water column between fresh water and ocean water being used to power reverse osmosis in a 4000 foot part of the ocean. The article didn't specify the method but I surmised it was the difference in head pressure would drive the reverse osmosis, leaving a pipe at the surface full of drinkable water that could be pumped to shore, while the currents at the depths carried away the saltier water. The energy for this apparently came from the weight of the salt falling downward.
ReplyDeleteNice in theory, but ocean water is incredibly corrosive and full of organics that would clog an RO membrane very quickly. Plus, the Three Laws of Thermodynamics want a word about the actual energy required.
DeleteI class this with the Facebook videos claiming to show a free-energy generator: Scams.
Yes they mentions the corrosion, the organic debris and the difficulty of accessing the RO modules at depth.
DeleteIt will, and they will turn back into the desert that used to be there...
ReplyDeleteOne of my kids recently emigrated from Phoenix to Lisbon and concern over future availability of water was one of their reasons.
ReplyDelete