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Science: We are turning the West into a desert

February 22, 2008

drybed-large.jpgA major new study in Science by a dozen water experts, concluded humans are the primary cause of changes in Western river flow, winter air temperature and snow pack in the past 50 years — and things will only get worse if we don’t act soon. The abstract of the study, “Human-Induced Changes in the Hydrology of the Western United States” (subs. req’d), led by the Scripps Institution of Oceanography, states:

Observations have shown that the hydrological cycle of the western United States changed significantly over the last half of the 20th century. We present a regional, multivariable climate change detection and attribution study, using a high-resolution hydrologic model forced by global climate models, focusing on the changes that have already affected this primarily arid region with a large and growing population. The results show that up to 60% of the climate-related trends of river flow, winter air temperature, and snow pack between 1950 and 1999 are human-induced. These results are robust to perturbation of study variates and methods. They portend, in conjunction with previous work, a coming crisis in water supply for the western United States.

The study’s conclusion is stark:

Our results are not good news for those living in the western United States. The scenario for how western hydrology will continue to change has already been published using one of the models used here [PCM (2)] as well as in other recent studies of western U.S. hydrology. It foretells water shortages, lack of storage capability to meet seasonally changing river flow, transfers of water from agriculture to urban uses, and other critical impacts. Because PCM performs so well in replicating the complex signals of the last half of the 20th century, we have every reason to believe its projections and to act on them in the immediate future.

The time to act is now!

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13 Responses to “Science: We are turning the West into a desert”

  1. Beefeater says:

    The part you left out:

    The west naturally undergoes multi-decadal fluctuations
    between wet and dry periods (12). If drying from natural
    climate variability is the cause of the current changes, a
    subsequent wet period will likely restore the hydrological
    cycle to its former state.
    But global and regional climate
    models forced by anthropogenic pollutants suggest human
    influences could have caused the shifts in hydrology (2, 13–
    15). If so, these changes are highly likely to accelerate,
    making modifications to the water infrastructure of the
    western U.S. a virtual necessity.

    As usual the have to point out that this has all happened before but that this time it’s a disaster.

    This winter has seen the return of record snow pack and rains in the Southwest that even the meteorologists with all their charts and graphs and computer models can’t explain.

  2. Dano says:

    As usual the have to point out that this has all happened before but that this time it’s a disaster.

    The denialist’s buddy, Pielke Sr, said pretty much the same thing.

    I guess the denialist here doesn’t know wtf he’s talking about. Shocking, surely.

    Best,

    D

  3. Beefeater says:

    It’s hard to refute such scientific statements as

    models forced by anthropogenic pollutants suggest human influences could have caused the shifts in hydrology (2, 13–
    15). If so, these changes are highly likely to accelerate,

    You have to be a “true believer” to accept this as scientific fact. I’m not surprised though, many seem to make that leap of faith.

  4. Beefeater says:

    Besides the title of the article is a bit disingenuous, the west already was a desert. Thousands of years ago the natives on the land constructed a large network of irrigation canals to move water around. They are still in evidence today. Fossil remains indicate that millions of years ago it was a swampy land with dinosaurs. And humans had nothing to do with the change. It is what it was.

  5. Dean says:

    You don’t have to believe anything about global warming to know that the West is in for serious water trouble sooner or later. Just look at the tree ring data. There are serious droughts lasting for over a hundred years in that record. Even if you deny that there’s any human forcing for the climate, you still have to predict that they are in for trouble in the future. Suburbs of Las Vegas and Phoenix like Henderson and Scottsdale are on track to follow the cliff houses of the Anasazi into oblivion.

  6. Beefeater says:

    Suburbs of Las Vegas and Phoenix like Henderson and Scottsdale are on track to follow the cliff houses of the Anasazi into oblivion.

    Now you get it! It’s called “climate change”. Evolution. The world was not created the day you were born with an unchanging “normal” climate. That’s the problem with the new “religion” of “Global Warming”, it has become an unwavering belief system as close minded as any other fundamentalist religion.

    2 miles from my subdivision here in Phoenix, ASU students from the Archeology Department dig fossils and identify ancient plant and animal remains every semester. Someday it will all change again with or without human intervention.

    And my house will turn back to dust.

  7. John L. McCormick says:

    Beefeater, your religion is as resolute as that of the AGW believers. Big difference is that the denier sees increasing warming of the earth surface and consequent drying in already dry areas as a part of the grand plan of nature.

    IPCC has relied upon real observations and not ancient history to project where AGW is going.

    You are satisfied to let this moment of climate change play itself out and all will go back to the way it was…’nothing we can do to alter that’.

    I and people willing to step back from their comfort zones see the warming increasing to a point where positive feedback from the melting permafrost and tundra flip conventional climate cycles into something akin to conditions liken to one of the post-extinction eras in earth history.

    Yes, Lost Wages was built on a desert as was most of the urban areas of the southwest. Water demand has increased along with the population and ag economy but the Colorado River flow has not. And, shorter winters, earlier spring runoff are major complicating factors.

    You may be able to relocate before Lake Mead intake pipes pop above the surface. Most will not have that chance and eventually the wheels of commerce will start to wobble and come loose.

    And, the heat goes on….regardless of your certainty about events of the past having happy endings. Would you feel the same about your house turning to dust because you and the global, collective WE made that happen?

    John L. McCormick

  8. zota says:

    my subdivision here in Phoenix

    Good thing humans have absolutely no role in anything that happens. Otherwise the people living in desert suburbs would have to feel some sense of responsibility for their choices.

    Fortunately, the combined industrial power of the human race is impotent and ineffectual, and all of Beefeater’s actions are totally free of consequence…

    What a relief!

  9. John L. McCormick says:

    The Oil Drum has a most appropriate and timely thread any visitor to this discussion should tune into.

    It is at:

    http://www.theoildrum.com/node/3652

    titled:

    Fire and Rain: The Consequences of Changing Climate on Rainfall, Wildfire and Agriculture

    It begins with the following statement and is worth your time:

    [The consequences of climate change are often presented in the media as coastal flooding after the melt of Greenland or Antarctic ice. That is the headline most often seen, however the real problems will be much more extensive. I'd like to look at some of those problems, in particular those of wildfire and agriculture, and provide a little background to better illustrate their severity.]

    It is not all about growing cotton and almonds in the Central Valley. Forests are on the firing line. They go and we go with them.

    John McCormick

  10. Beefeater says:

    John, I’m not denieing “Climate Change”! I accept it probably more than AlGore! But explain this for me.

    Imagine you are a SCUBA diver exploring the bottom of southern Lake Huron. In the gloomy light near the bottom, you see what appears to be a log, some branches, and other wood debris. You take little notice of these until you see a stump, with some obvious roots penetrating into the bottom. This seems impossible since it suggests this tree once grew here, a few miles offshore in 40 ft of water. Although the logs and branches could have floated out from shore and sunk once they became waterlogged, the stump could have grown in this position only if this area was once dry land.
    Scenes like this are found in several areas of the Great Lakes. They represent undeniable evidence that water levels in the Great Lakes were once radically lower than they are today, making some of our concerns about recent low water levels pale in comparison. Imagine 300 feet lower!
    At various periods during the past 11,000 years (the Holocene Epoch) the levels of Lakes Michigan and Huron were higher as well as lower than at present. During the last period of low water, forests spread over much of the area that was formerly under water. Later, as the lakes refilled from glacial melt-water and experienced redirected drainage, the trees were killed as they became flooded, leaving behind evidence of their existence in the form of logs and stumps comprising a “drowned forest”.
    Divers examine a stump rooted on the bottom of Lake Huron
    Before the Holocene Epoch, there were multiple periods of glaciation over the 2 million years known as the Pleistocene Epoch or“ice age”. During the Pleistocene, geologists have documented that glaciers repeatedly advanced and retreated, often covering major parts of North America, including the Great Lakes, with a kilometer or more of ice. The last of these, known as the Wisconsin glaciation,has left behind a number of clues attesting to its existence and extent.

    http://www2.oakland.edu/ biology/ files/ drownedforest.pdf

    Read this bit of history, the science channel did a program on the subject also, and then explain to me what part of climate change you don’t understand.

    It changes all the time whether human animals are around or not! How arrogant do you have to be to think that we can control the climate?

  11. Joe says:

    Not arrogant. No one believes we can “control” the climate, just destroy it or save it. That’s what the science says. Since you aren’t open to the facts, I can’t really urge anyone to argue with you.

  12. Beefeater says:

    Joe
    “Since you aren’t open to the facts”.

    I present facts that are provable, not based on predictions, computer models, chicken entrails or some political agenda. I’m not a “denier” nor do I believe that the world was created 6000 years ago. If anyone finds the facts inconvenient it would be those who seem to have something to gain by being an alarmist.

    You say you don’t believe we can control the climate, but the ultimate control would be the ability to “destroy or save” it.

    I realize you can’t urge anyone to argue with me, it would disrupt your little scam here. You have to much invested in being an alarmist.

    Not that there is anything wrong with that, everyone has to eat.

  13. Jay Alt says:

    Beefeater-
    I am here to talk solutions, not to argue. You bring up some changes through the centuries and link a finding on the ancient level of the Great Lakes.

    Old tree stumps show that an ancient forest is now underwater. That is no surprise to those who study lakes. The land around the Great Lakes still rebounds from the weight of glaciers. This occurs at different rates – the north shores of the lakes rise faster than the south. This has caused the outlet of the Great Lakes to shift from emptying into James Bay to draining down the St. Lawrence. The difference in rebound rates has a tilting effect on the landscape. The northern shores of Superior, Michigan and Huron are raised up compared to the southerns ends of the lakes. Look at the article you link. The sunken forest at Sanilac is a red dot at the S. end of Huron.

    The submergence of that forest ~7,000 yrs ago occurred by a process that is now understood – landscape changes due to glacial isostatic rebound.

    Observation of glacial isostatic adjustment in ‘‘stable’’ North America with GPS (see abstract)
    http://geodesy.noaa.gov/ CORS/ Articles/ 2006GL027081.pdf

    Post-glacial rebound
    http://en.wikipedia.org/wiki/Post-glacial_rebound

    Box 1 – (Comments about Duluth apply to the Sanilac site on L. Huron)
    http://pubs.usgs.gov/ circ/ 2007/ 1311/ pdf/ circ1311_web.pdf

    The difference in lake levels has little to do with global warming. But scientific theories do provide valid explanations of both phenomena.