February 23, 2011
American Pacific Northwest Headed For Drier Climate?
The 20th century was an outlier in terms of precipitation.
PITTSBURGH—University of Pittsburgh-led researchers extracted a 6,000-year climate record from a Washington lake that shows that the famously rain-soaked American Pacific Northwest could not only be in for longer dry seasons, but also is unlikely to see a period as wet as the 20th century any time soon. In a recent report in the Proceedings of the National Academy of Sciences, the team linked the longer dry spells to the intensifying El Niño/La Niña climate pattern and concluded that Western states will likely suffer severe water shortages as El Niño/La Niña wields greater influence on the region.
The researchers analyzed a sediment core from Castor Lake in north central Washington to plot the region’s drought history since around 4,000 BCE and found that wet and dry cycles during the past millennium have grown longer. The team attributed this recent deviation to the irregular pressure and temperature changes brought on by El Niño/La Niña. At the same time, they reported, the wet cycle stretching from the 1940s to approximately 2000 was the dampest in 350 years.
Some climate scientists believe the whole American West was populated during an especially wet period and now we face a period of declining water availability running up against growing populations. Whoops. As goes Lake Mead, so goes the West.
The main reason why Lake Mead, currently only 40% full, has been getting emptier is a decade-long drought. Whether this is a cyclical and normal event, or an early sign of climate change, is unclear.
Las Vegas is extremely vulnerable to the drought which is draining Lake Mead.
Ninety percent of southern Nevada’s water comes from Lake Mead, with releases regulated by the Southern Nevada Water Authority.
The climate changes even without human intervention. Our ability to adapt to droughts depends very heavily on the cost of energy. Given really cheap energy massive desalinization plants could produce massive quantities of water which could be pumped inland. If the energy does not become cheap then desal is a much more expensive proposition.
There are some indications that desal will become less energy hungry due to improved materials as we become more adept at precision manufacturing at ever smaller scales.
Heck, desal could become a slight net energy producer, in some places, given really efficient membranes that don't need cleaning. All you need to do is drop a rigid pipe with a desal membrane across the end into the sea, filled with fresh water. Because fresh water is less dense than salt, the deeper it goes, the more of a pressure difference you get across the membrane. There are plenty of places where the sea is deep enough to produce enough pressure to drive reverse osmosis.
And, no, it's not a perpetual motion machine, the energy comes from dropping salt to the bottom of the ocean.
"The climate changes even without human intervention."
The climate ALWAYS changes.
"Whether this is a cyclical and normal event, or an early sign of climate change, is unclear."
Right, because let's focus on that which we really can't control - the desire of humans everywhere (developing countries especially) to use more energy - rather than on that which we can change - the immigration across our borders. The Salt Lake Valley was barely half-developed 20 years ago. Today it's almost completely built up, thanks to massive immigration, both direct (legals, illegals and refugees) and indirect (whites fleeing the mess in California caused by too much immigration). Droughts were commonplace here 20 years ago, when I was a kid. How are we supposed to deal with them with 2-3 times the population?
We've created an insanely unstable situation in the US. For two decades we've had heavy growth in the most arid regions of the country. 45% of our newborns are to races with less than 50% high school graduation rates. Our budget deficit is $1.5 trillion a year, and home prices still haven't bottomed out. My only wish is that the West was in the middle of a drought cycle, as it was 5 years ago. We've had a very wet winter. If on top of all the other chaos we were also in a drought we might be a bit more clear-eyed about the harm done by mass immigration. Even with 9% unemployment, my Republican dominated state legislature still can't get a serious immigration enforcement bill passed, and is actually considering its own "guestworker" program.
There's an enormous difference between the water needs of individuals for drinking and bathing, versus industria/ and agricultural uses. Individuals don't use that much, and either recycling or desalination would work just fine.
On the other hand, I/Ag needs need more thought. Should we be farming in deserts?? Should we inmclude the cost of water use in our comparisons of thermal electrical generation with non-thermal generation like wind and PV?
Some say we just need to change the way we are using water (and in particular, reform the whole agricultural system).
This includes reduction in low-priority uses. For example, sewage effluent requires 1500 kWh/AF (an AF is roughly 326,000 gallons) and seawater requires 5400 kWh/AF. It is the largest single component in the cost of the water--especially in a high electricity rate state like California. Roughly 50% of the water we consume in Southern California goes to landscaping. The average household in Huntington Beach uses 2.5 AF per year.
Nobody is going to turn to desalinization when dams are cheaper. When push comes to shove, the eco-extremists will be pushed aside and reality instituted. Water storage reservoirs will be constructed to add whatever "drinking water" requirements are needed - perhaps after all agricultural water rights have been purchased/expropriated. That is the reality of water in dry areas.
As to any purported forecasts about climate .... when the weathermen can get an accurate forecast a few days in advance, I will worry a bit more about projected climate changes years in advance. Right now, any prediction about earth being destroyed by an asteroid is more likely. Likelihood of climate prediction being correct = approximately Zero
Asteroids with diameters of 5 to 10 m (16 to 33 ft) enter the Earth's atmosphere approximately once per year
Asteroids with a 1 km (0.62 mi) diameter strike the Earth every 500,000 years on average
Large collisions – with 5 km (3 mi) objects – happen approximately once every ten million years.
“History doesn't repeat itself - at best it sometimes rhymes” Mark Twain
Nobody is going to turn to desalinization when dams are cheaper.
The Colorado river is dry by the time it gets to Mexico. The same is true for other major rivers, in places like China.
What regions are you thinking about?
Are you saying it costs 5400 kWh/AF to do desalinization? If so, that's about $600 per AF and at 2.5AF per household we are talking $1500 per household if water was produced from the sea. That's expensive. Cut out lawn watering and use far more water-efficient appliances and do more recycling and then what? $500? $250? Of course, California electric power costs more than in the rest of the United States.
An empty Lake Mead won't be cheap.
forget existing lakes except where u can raise the existing level w minimal cost -- - think NEW DAMS
there are hundreds of alpine valleys we can (and will) flood --- rofl
just find a valley with a canyon and you got x marks the spot - there are literally thousands in western US
Nick - we are not talking about hydro - altho that is possible on some - we are talking about headwaters rubble fill dam drinking water impoundments close by cities and towns. Minimal distance and minimal pipline *if any* cost. Our town uses the stream bed to run the water into town where it is treated and fed into the water supply. More smaller dams are better than one huge one anyway, for water year averaging, etc.
Cheap, effective, reliable, as long as your engineers are not corrupt or incompetent. Lord help you otherwise lol
I seem to recall a lot of history books hee-heeing at those stupid pioneers who called it "The Great Western Desert". Oh, wait.