Welcome To The 'Megadrought'

Pinon Pines Near Los Alamos, New Mexico in 2002 (Left) and 2004 (Right) Courtesy Oregon State University via Flickr

The 2000-2004 North American Drought Was The Worst In 800 Years -- Popular Science

Welcome to the 'megadrought'.

An analysis of past climate data published yesterday in the journal Nature Geoscience paints a less-than-rosy picture for the U.S., Mexico, and Canada in the 21st century. The 2000-2004 dry spell was the worst drought in the region in 800 years, the researchers claim, and before the century is over we’ll look back on those days as the wetter end of a much larger hydroclimate shift. Dry conditions will become the “new normal.” They invoked the word “megadrought.”

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My Comment: Dry conditions becoming the “new normal” .... not a comforting thought if you live on the plains.

Amazon Drought 'Severe' In 2010

Amazon Drought 'Severe' In 2010, Raising Warming Fears -- BBC

Last year's drought in the Amazon raises concerns about the region's capacity to continue absorbing carbon dioxide, scientists say.

Researchers report in the journal Science that the 2010 drought was more widespead than in 2005 - the last big one - with more trees probably lost.

The 2005 drought had been termed a "one in a century" event.

In drought years, the Amazon region changes from being a net absorber of carbon dioxide into a net emitter.

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My Comment: This is not the first time that a drought has occurred in the Amazon .... but if it continues .... it will be a good reason to be concerned.

Africa-wide "Great Green Wall" To Halt Sahara's Spread?

Acacia trees line an African landscape in an undated picture. Picture by Tim Laman, NGS

From National Geographic:

China built its famous Great Wall to keep out marauders. Now, millennia later, a "Great Green Wall" may rise in Africa to deter another, equally relentless invader: sand.

The proposed wall of trees would stretch from Senegal to Djibouti as part of a plan to thwart the southward spread of the Sahara, Senegalese officials said earlier this month at the UN's Copenhagen climate conference.

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California Droughts When Planet Warms?

From Future Pundit:

Why worry about earthquakes when we can worry about massive droughts instead?

California experienced centuries-long droughts in the past 20,000 years that coincided with the thawing of ice caps in the Arctic, according to a new study by UC Davis doctoral student Jessica Oster and geology professor Isabel Montañez.

The finding, which comes from analyzing stalagmites from Moaning Cavern in the central Sierra Nevada, was published online Nov. 5 in the journal Earth and Planetary Science Letters.

Global warming gets a lot of attention due to the prospects of huge low lying areas getting submerged. But big changes in regional climate - whether human caused or not - seem much more interesting to me. Such changes could occur at any time.

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Scientists Reveals Secrets Of Drought Resistance

Soybean sprouts struggling in dry conditions. Biologists have now solved the structure of a critical molecule that helps plants survive during droughts. (Credit: iStockphoto/Matt Niebuhr)

From Science Daily:

Science Daily (Oct. 23, 2009) — A team of biologists in California led by researchers at The Scripps Research Institute and the University of California (UC), San Diego has solved the structure of a critical molecule that helps plants survive during droughts. Understanding the inner workings of this molecule may help scientists design new ways to protect crops against prolonged dry periods, potentially improving crop yields worldwide, aiding biofuels production on marginal lands and mitigating drought's human and economic costs.

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Satellites Unlock Secret To Northern India's Vanishing Water

The map shows groundwater changes in India during 2002-08, with losses in red and gains in blue, based on GRACE satellite observations. The estimated rate of depletion of groundwater in northwestern India is 4.0 centimeters of water per year, equivalent to a water table decline of 33 centimeters per year. Increases in groundwater in southern India are due to recent above-average rainfall, whereas rain in northwestern India was close to normal during the study period. (Credit: I. Velicogna/UC Irvine)

From Science Daily:

ScienceDaily (Aug. 19, 2009) — Using satellite data, UC Irvine and NASA hydrologists have found that groundwater beneath northern India has been receding by as much as 1 foot per year over the past decade – and they believe human consumption is almost entirely to blame.

More than 109 cubic kilometers (26 cubic miles) of groundwater disappeared from the region's aquifers between 2002 and 2008 – double the capacity of India's largest surface-water reservoir, the Upper Wainganga, and triple that of Lake Mead, the largest manmade reservoir in the U.S.

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West Africa Faces 'megadroughts'

From The BBC:

Severe droughts lasting centuries have happened often in West Africa's recent history, and another one is almost inevitable, researchers say.

Analysis of sediments in a Ghanaian lake shows the last of these "megadroughts" ended 250 years ago.

Writing in the journal Science, the researchers suggest man-made climate change may make the situation worse.

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