Showing posts with label Drought. Show all posts

Written by fatih al-farahat in Drought

IPCC was not wrong about the Amazon's high sensitivity to drought

The Grumble in the Jungle

by Rob Painting, Skeptical Science, October 29, 2010

An article in a British newspaper claimed that the Intergovernmental Panel on Climate Change (IPCC) published wrong information about the Amazon Rainforest in their 2007 report. The issue centred on the statement that about 40% of the Amazon was susceptible to the effects of drought, or more specifically "slight reductions in rainfall".

The Amazon is the world's largest tropical rainforest, and due to its immense size, has a global effect on the Earth's climate. Despite being well adapted and resilient to wet and dry periods which occur throughout the year, the rainforest is vulnerable to extended periods of drought. Any major decline in the health of the Amazon rainforest is likely to impact the world climate.

The skeptic claims relate to section 13.4.1 of the IPCC Fourth Assessment Report (2007) which made the statement: 'Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation; this means that the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state, not necessarily producing gradual changes between the current and the future situation' (Rowell and Moore, 2000)

The reference is to a non-peer reviewed report prepared by the World Wide Fund for Nature (WWF) which itself cites an original peer reviewed study (Nepstad 1999) as the basis for the claim. The citations in the WWF and IPCC reports are not complete, Nepstad 1994, Nepstad 1999 and Nepstad 2004support the claim that up to half the Amazon rainforest were severely affected by drought. Further studies, carried out since the 2007 IPCC report, reinforce the Amazon's susceptibilty to long term reductions in rainfall .

The IPCC could have avoided confusion by simply citing the peer reviewed studies themselves, rather than the WWF report and perhaps "slight reduction" should have been better defined or qualified. Despite the error in citation, the statement made by the IPCC is factually correct. Maybe the last word should go to the lead author of the papers upon which the statements were based, Daniel Nepstad, who made a public press release to clear up the mainstream media confusion over the subject. Nepstad concludes:

"In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement.

This post is the Basic Version (written by Rob Painting) of the skeptic argument "IPCC were wrong about Amazon rainforests".

Link: http://www.skepticalscience.com/The-grumble-in-the-jungle.html

Written by fatih al-farahat in Consequences of warming, Drought

Climate change to triple Australia fire danger

Climate change to triple Australia fire danger: report

January 28, 2010

SYDNEY (AFP) – Climate change could more than triple the risk of catastrophic wildfires in parts of Australia, a top environmental group warned Thursday, almost a year since savage firestorms that killed 173 people.

Greenpeace warned that, without a new climate treaty to replace the Kyoto Protocol, the frequency of severe fire danger in drought-parched southeastern Australia would grow three-fold by 2050.

"Catastrophic" conditions similar to those ahead of February 2009's so-called "Black Saturday" wildfires which killed 173 people in towns around Melbourne would occur once every three years, instead of once in every 33.

"The frequency of catastrophic fire danger could increase more than tenfold in Melbourne, and the number of total fire ban days could triple in Sydney, Adelaide and Canberra by 2050," according to a Greenpeace report entitled "Future Risk."

If targets for emission cuts proposed by world leaders at December's Copenhagen summit were adopted in a new global treaty, southeastern Australia would still face at least a doubling of severe fire risk, Greenpeace said.

"If we do nothing to address climate change we are knowingly placing more lives and property at risk," said Greenpeace CEO Linda Selvey.

According to the report temperatures in Australia had warmed an average 0.9 °C (1.6 °F) since 1950, with the greatest intensification of heat in the country's east, which was accompanied by markedly declining rainfall.

"Hotter, drier weather is a recipe for bushfire disaster in regions of Australia home to the majority of the population," it said, adding that the changing climate had "noticeably" prolonged the annual fire season.

The February 7, 2009, Black Saturday fires were the worst natural disaster in Australia's modern history, with one expert likening their intensity to the energy produced by 1,500 Hiroshima atomic bombs.

More than 2,000 homes were destroyed, killing 173 people and injuring more than 400.

Australia this week reiterated its Copenhagen goal for emissions cuts of between five and 25% of 2000 levels by 2020, depending on commitments by other nations, and said they would be formally submitted to the UN.

Link: http://news.yahoo.com/s/afp/20100128/sc_afp/australiaclimatewarmingweatherfire

Written by fatih al-farahat in Drought, resource scarcity, Water shortage

Wyoming water may become more scarce with climate change

Report: Wyoming water vulnerable to climate change

by MEAD GRUVER, trib.com, January 31, 2010

The mountain snows that replenish most surface water in Wyoming, the fifth-driest state, are vulnerable to climate change and likely to be affected by rising temperatures, a new report says.

The report released this week by the Ruckelshaus Institute of Environment and Natural Resources at the University of Wyoming also says downstream water demand is expected to increase in the decades ahead because of regional population growth.

The Ruckelshaus Institute is a think tank for environmental issues. A variety of interests are represented on the institute's board of directors, including environmental groups, industry, academia and government.

Most of Wyoming's surface water originates as mountain snowpack. Climate change can cause snowpack to melt earlier during the springtime, making runoff more challenging to manage as a water source, the report says.

Reservoir managers have the task of striking a balance between flood control and water storage.

"Moreover, an early runoff leads to diminished late-season flows," the report says, "which are crucial to a wide variety of municipal, agricultural, industrial and environmental uses."

The report also points out that Wyoming is located at the headwaters of several river systems, making the state more vulnerable to drought because not much water flows into the state.

Yet higher temperatures intensify drought.

"The amount of temperature increase that we're expecting in and of itself would have some pretty dramatic effects in Wyoming and the West," said Steve Gray, state climatologist and director of the Water Resources Data System.

The report shows that Wyoming needs to take a "realistic view" of climate change in managing its water, Gray said. That means planning for extremes, not just the average amount of water available.

"We just plan around that number rather than asking tougher questions in some ways," he said. "What's our worst case?"

More than 70% of Wyoming receives less than 16 inches of precipitation a year. That's not dry enough to qualify as desert, the report said, but still plenty dry.

Compared to precipitation patterns over the past millennium, the 20th century was unusually wet. Long droughts -- some lasting 50 years or more -- have been fairly common in the region over the long run.

With or without climate change, Gray said, Wyoming should expect such patterns to continue.

One way to do that is to build reservoirs. Another, he said, is to conserve water.

Ruckelshaus board members were struck by a variety of studies about how climate change could affect Wyoming, said Indy Burke, a professor and director of the institute.

"They said, 'My god, the citizens need to know this. We need to get this out," she said.

She said more science is needed to find out what else in Wyoming is sensitive to climate change.

Link: http://www.trib.com/news/state-and-local/article_c80a020e-91b2-5ee5-8459-a83a73d3b5d6.html

Written by fatih al-farahat in Drought, East Antarctica, Water shortage

Western Australia drought is possibly the worst for the past 750 years

WA drought 'could be worst for 750 years'

by CHALPAT SONT, Western Australia Today, February 9, 2010

Scientists have made a surprising link between climate patterns in Australia and Antarctica.

If you thought the drought affecting south-west WA since the 1970s was extreme, you were right.
But just how extreme has been a matter of contention.

Now, scientists believe it could be the worst of its kind in 750 years, after making an unexpected discovery.
Researchers from the Australian Antarctic Division and Antarctic Climate and Ecosystems Co-operative Research Centre have identified a link between the drought, which began in the early 1970s, and snowfall at a site in East Antarctica over the same period.

In research published in Nature Geoscience, they say the relationship is inverse: high snowfalls at the Law Dome site correlate with low rain in the South-West.

This is a result of the atmospheric circulation pattern that brings dry, cool air to Australia, while sending warm, moist air to East Antarctica.

However, the high snowfall at Law Dome was unlike any other in the past 750 years, and led the researchers to believe the drought was similarly unusual.

Since the 1970s, there has been a decline of up to 20% in winter rainfall in the South-West and, though the cause of the drought remains unclear, others have pointed to land-use changes, ocean temperatures, air circulation changes and natural variability.

But its severity has been hard to calculate, with weather records going back only about 100 years, and the oldest tree-ring record, 350 years, from a site that has not been affected by the drought.

The researchers found that the snowfall was of a severity expected only once in every 38,000 years.

Adjusting their analysis of ice cores, it still should happen only about every 5400 years.

"It also suggests ... that if the mix of factors that influence [South-West] rainfall over the past century reflects that of the longer term, then the recent drought ... may be similarly unusual," the researchers say.

Lead researcher Tas van Ommen said the results of the study were unexpected.

"We were surprised at first, given the complexity of climate processes, to find such a direct connection between our ice core and the climate of Western Australia," he said.

"By identifying new processes that influence regional Australian climate, this work offers the possibility to improve understanding and reduce uncertainty in future projections of climate change.

"This work underscores the need for long-term records of past climate from sources like ice cores and it illustrates the important role that Antarctic climate processes play globally."

It suggested human influence was likely to have played a role in the drought, Dr van Ommen said.

University of NSW professor Andy Pitman said the study was a "good and bad news story."

"It is good for those policy makers in WA who invested in alternative sources of water based on earlier research by CSIRO and Bureau of Meteorology," he said.

"This new science suggests they made a wise decision. It is, of course, less good news for the future of water dependent industries in WA and reinforces the urgent need for global cuts in greenhouse gas emissions."

Monash University professor Neville Nicholls said the researchers may even have underestimated the severity of the drought.

"Since about 1990, snowfall at their site in Antarctica appears to have decreased, but the South-West rainfall has not rebounded as we might have expected from this," he said.

"This indicates that some additional mechanism is affecting either snowfall or the drought. This is not surprising in a time of strong global warming. But we do need to work out these mechanisms."

Link: http://www.watoday.com.au/environment/climate-change/wa-drought-could-be-worst-for-750-years-20100205-niee.html

Written by fatih al-farahat in Andrew C. Revkin, australia, Drought, Joseph Romm

Joe Romm insists Andy Revkin stop misrepresenting climate scientists in his tweets

Australian Scientists: Contrary to media reports (and tweets), “our paper does not discount climate change as playing a role in this most recent drought, the ‘Big Dry.’ In fact, there are indications that climate change has worsened this recent drought.”

"The severity of the 'Big Dry' has been exacerbated by recent warmer air temperatures over the past few decades.... In a warmer world, the severity of droughts would likely become far worse." (Duh)

by Joseph Romm, Climate Progress, January 19, 2010

Australia is most definitely getting hotter, much as the entire planet has, much as climate scientists have been predicting would be the inevitable result of unrestricted emissions of heat-trapping greenhouse gases.

The figure is from the “Annual Australian Climate Statement 2009,” which notes:

2009 ends Australia’s warmest decade on record, with a decadal mean temperature anomaly of +0.48 °C (above the 1961-90 average). In Australia, each decade since the 1940s has been warmer than the preceding decade. In contrast, decadal temperature variations during the first few decades of Australia’s climate record do not display any specific trend. This suggests an apparent shift in Australia’s climate from one characterised by natural variability to one increasingly characterised by a trend to warmer temperatures.

At the same time, parts of Australia are getting drier, much as as climate scientists have been predicting would be the inevitable result of unrestricted emissions of GHGs. And Dr. Bertrand Timbal, of the Bureau of Meteorology’s Centre for Australian Weather and Climate Research (CAWCR), concludes in his paper, “The continuing decline in South-East Australian rainfall: update to May 2009”:

The recent 12 year, 8 month period is the driest in the 110 years long record, surpassing the previous driest period during WWII….

This change in the relative contributions by the autumn and spring seasons now more closely resembles the picture provided by climate model simulations of future changes due to enhanced greenhouse gases.

So it was odd that Andy Revkin tweeted to disagree with the following statement in a recent guest essay by Auden Schendler and Mark Trexler (“The coming climate panic? Will U.S. conservatives usher in the era of permanently big government?”):

Meanwhile, that very planet is visibly changing—epic droughts, fires and dust storms in Australia; floods in Asia, alarmingly fast melting of land ice in Greenland and Antarctica; the prospect of an ice-free summer on the Arctic Sea; raging, unprecedented fires throughout the world; and mosquito-borne illnesses like Dengue spreading to regions previously untouched. Measurements show that the oceans are rising and becoming more acidic, while the Earth’s average temperature was higher in the past decade than at any time in the past century.

At some point, even climate change becomes teenager obvious: “Well, duh, Dad! Look around you!”

The constraints of twittering turn that statement by Schendler and Trexler into this Revkin tweet (see “Why journalists should not twitter, Parts 87, 88, 89”)

Joe R still sees Aussie’s Big Dry as co2-driven event http://j.mp/co2panic Not what climate scientists see: http://j.mp/AusDry

Now aside from the misattribution from Schendler/Trexler to me, it turns out that the authors of the study Revkin cites were concerned enough about the misreading of their work in the media that they issued a “Clarification,” which begins:

The implications of our work (Ummenhofer et al., 2009) have been misunderstood in some media commentary, with some reporters asserting we have discovered that south-eastern Australia’s recent “Big Dry” is not related to climate change. This is not correct.

Their study focused on the connection between negative Indian Ocean Dipole (IOD) events and drought. Their clarification ends:

When taken in the context of other historic droughts over the past 120 years, the “Big Dry” is still exceptional in its severity. The last negative IOD event occurred in 1992. This is the longest period on record over the past 120 years without a single negative IOD event.

Furthermore, the severity of the “Big Dry” has been exacerbated by recent warmer air temperatures over the past few decades (Figure 1). Warmer air temperatures lead to increased evaporation, which further reduces soil moisture and worsens the drought. While this work does not explicitly focus on the link between changing IOD frequency and recent regional and global warming, it does send a stark message: in a warmer world, the severity of droughts would likely become far worse.

In short, our paper does not discount climate change as playing a role in this most recent drought, the “Big Dry.” In fact, there are indications that climate change has worsened this recent drought. Refer to Abram et al. (2008), Cai et al. (2009), and Nicholls (2004) who investigate changes in IOD frequency and south-eastern Australian drought due to climate change.

Here is part of Figure 1, “Historical record of … mean climatic conditions over southeast Australia.”
AustraliaSE

Time series of anomalous … (c) 5-yr running mean of temperature (°C), with a 15-year running mean superimposed in green, and (d) 5-yr running mean of Palmer Drought Severity Index (PDSI) over southeastern Australia during June-October. The grey shaded bars highlight periods of below-average precipitation when the 5-year running mean falls below one standard deviation. The duration of three major droughts has been indicated in (d) with horizontal black bars.

So the work of these Aussie scientists cannot be used to argue that the “Big Dry” is not “a co2-driven event” (which in any case isn’t quite what had been asserted originally). Indeed, the scientists find that climate change has probably worsened this recent drought, which again is not new climate science (see “Must-have PPT: The ‘global-change-type drought’ and the future of extreme weather”). Warm-weather droughts are generally worse than cooler-weather droughts — and this has been a hot-weather drought, which is perhaps the worst of all. Future droughts will increasingly be very hot weather droughts.

So I repeat again:

Journalists simply shouldn’t be twittering on science or other subjects that require more than 140 characters to discuss intelligently, which is pretty much every topic.

Link: http://climateprogress.org/2010/01/19/australian-scientists-media-tweets-climate-change-play-role-in-drought-the-big-dry/

Written by fatih al-farahat in Drought, Water shortage

Las Vegas running out of water means dimming Los Angeles lights

by John Lippert and Jim Efstathiou, Jr.

February 26, 2009 (Bloomberg) -- On a cloudless December day in the Nevada desert, workers in white hard hats descend into a 30-foot-wide shaft next to Lake Mead.

As they’ve been doing since June, they’ll blast and dig straight down into the limestone surrounding the reservoir that supplies 90% of Las Vegas’s water. In September, when they hit 600 feet, they’ll turn and burrow for 3 miles, laying a new pipe as they go.

The crew is in a hurry. They’re battling the worst 10-year drought in recorded history along the Colorado River, which feeds the 110-mile-long reservoir. Since 1999, Lake Mead has dropped about 1% a year. By 2012, the lake’s surface could fall below the existing pipe that delivers 40% of the city’s water.

As Las Vegas’s economy worsens, the workers are also racing against a recession that threatens the ability to sell $500 million in bonds so they can complete the job.

Patricia Mulroy, manager of the Southern Nevada Water Authority, is the general in this region’s war to stem a water emergency that’s playing out worldwide. It’s the biggest battle of her 31-year career.

‘We’ve Tried Everything’

“We’ve tried everything,” says Mulroy, 56, who made no secret of her desire to become secretary of the U.S. Interior Department before President Barack Obama picked U.S. Senator Ken Salazar of Colorado in December.

“The way you look at water has to fundamentally change,” adds Mulroy, who, after 20 years of running the authority, said in January she’s ready to start thinking about looking for a new job, declining to say where.

Across the planet, people like Mulroy are struggling to solve the next global crisis.

From 2500 B.C., when King Urlama of Lagash diverted water in the Tigris and Euphrates Valley in a border dispute with nearby Umma, to 1924, when Owens Valley , California, farmers blew up part of the aqueduct that served a parched Los Angeles, societies have bargained, fought and rearranged geographies to get the water they need.

Mulroy started her push with conservation. She’s paying homeowners $1.50 a square foot (0.09 square meter) to replace lawns with gravel and asking golf courses to dig up turf. That helped cut Las Vegas’s water use by 19.4% in the 7 years ended in 2008, even as the metropolitan area added 482,000 people, bringing the total to 2 million. It wasn’t enough.

Paul Bunyan

So she’s planning a $3.5 billion, 327-mile (525-km) underground pipeline to tap aquifers beneath cattle-raising valleys northeast of the city. She’s even suggested refashioning the plumbing of the entire continent, Paul Bunyan style, by diverting floodwaters from the Mississippi River west toward the Rocky Mountains.

If Mulroy’s ideas are extreme, one reason is that the planet’s most essential resource doesn’t work like other commodities.

There’s no global marketplace for water. Deals for property, wells and water rights, such as the ones Mulroy must negotiate to build the pipeline, are done piecemeal. As the world grows needier, neither governments nor companies nor investors have figured out an effective and sustainable response.

“We have 19th-century ways of utilizing water and 21st-century needs,” says Brad Udall, director of Western Water Assessment at the University of Colorado at Boulder.

Unyielding Pressure

Water upheavals are intensifying because the population is growing fastest in places where fresh water is either scarce or polluted. Dry areas are becoming drier and wet areas wetter as the oceans and atmosphere warm. Economic roadblocks, such as the global credit crunch and its effects on Mulroy’s attempts to sell bonds, multiply during a recession.

Yet local governments that control water face unyielding pressure from constituents to keep the price low, regardless of cost. Agricultural interests, commercial developers and the housing industry clash over dwindling supplies. Companies, burdened by slowing profits, will be forced to move from dry areas such as the American Southwest, Udall says.

“Water is going to be more important than oil in the next 20 years,” says Dipak Jain , dean of the Kellogg School of Management at Northwestern University in Evanston, Illinois, who studies why corporations locate where they do.

No Cheap Water

Even before the now decade-long drought began punishing Las Vegas, people used more than 75% of the water in northern Africa and western Asia that they could get their hands on in 2000, according to the United Nations.

This is a long and very interesting article -- more at this link: http://mobile.bloomberg.com/apps/news?pid=2065100&sid=a_b86mnWn9.w

Written by fatih al-farahat in Drought, Water shortage

CERES Report: Looming water crisis could unravel world economy without radical action, investors told – 'more important than oil'

Water 'more important than oil' businesses told

Looming water crisis could unravel world economy without radical action, investors told

by Juliette Jowit, The Guardian, 26 February 2009

Water shortage will cause greater ruin than peak oil. Photograph: Pedro Armestre/AFP/Getty Images

Dwindling water supplies are a greater risk to businesses than oil running out, a report for investors has warned.

Among the industries most at risk are high-tech companies, especially those using huge quantities of water to manufacture silicon chips; electricity suppliers who use vast amounts of water for cooling; and agriculture, which uses 70% of global freshwater, says the study, commissioned by the powerful CERES group, whose members have $7 trillion under management. Other high-risk sectors are beverages, clothing, biotechnology and pharmaceuticals, forest products, and metals and mining, it says.

"Water is one of our most critical resources – even more important than oil," says the report, published today . "The impact of water scarcity and declining water on businesses will be far-reaching. We've already seen decreases in companies' water allotments, more stringent regulations [and] higher costs for water."

Droughts "attributable in significant part to climate change" are already causing "acute water shortages" around the world, and pressure on supplies will increase with further global warming and a growing world population, says the report written by the US-based Pacific Institute.

"It is increasingly clear that the era of cheap and easy access to water is ending, posing a potentially greater threat to businesses than the loss of any other natural resource, including fossil fuel resources," it adds. "This is because there are various alternatives for oil, but for many industrial processes, and for human survival itself, there is no substitute for water."

In a joint statement, CERES' president Mindy Lubber and Peter Gleick, president of the Pacific Institute, urged more companies and investors to work out their dependence on water and future supplies, and make plans to cope with increased shortages and prices.

"Few companies and investors are thinking strategically about the profound business risks that will exist in a world where climate change is likely to exacerbate already diminishing water supplies," they say.

"Companies that treat pressing water risks as a strategic challenge will be far better positioned in future," they add.

The CERES report adds to growing concern about a looming water crisis. In the Economist's report, The World in 2009 , Peter Brabeck-Letmathe, chairman of food giant Nestlé, wrote: "under present conditions… we will run out of water long before we run out of fuel." And at its annual meeting this year the World Economic Forum issued what it itself called a "stark warning" that "the world simply cannot manage water in the future in the same way as in the past or the economic web will collapse."

CERES, which has members in the US and Europe, made recommendations, including that companies should measure their water footprints from suppliers through to product use, and integrate water into strategic planning, and that investors should independently assess companies' water risk and "demand" better disclosure from boards.

Link to article: http://www.guardian.co.uk/environment/2009/feb/26/water-drought

Global Warming