Showing posts with label desert. Show all posts
Showing posts with label desert. Show all posts

Thursday, July 17, 2014

'Peak soil' threatens future global food security

Nigel Hunt and Sarah Mcfarlane in Reuters: The challenge of ensuring future food security as populations grow and diets change has its roots in soil, but the increasing degradation of the earth's thin skin is threatening to push up food prices and increase deforestation.

 While the worries about peaking oil production have been eased by fresh sources released by hydraulic fracturing, concern about the depletion of the vital resource of soil is moving center stage.  "We know far more about the amount of oil there is globally and how long those stocks will last than we know about how much soil there is," said John Crawford, Director of the Sustainable Systems Program in Rothamsted Research in England.  "Under business as usual, the current soils that are in agricultural production will yield about 30 percent less than they would do otherwise by around 2050."

Surging food consumption has led to more intensive production, overgrazing and deforestation, all of which can strip soil of vital nutrients and beneficial micro-organisms, reduce its ability to hold water and make it more vulnerable to erosion.

Such factors, exacerbated by climate change, can ultimately lead to desertification, which in parts of China is partly blamed for the yellow dust storms that can cause hazardous pollution in Asia, sometimes even severe enough to cross the Pacific Ocean and reduce visibility in the western United States....

An archive shot of the Dust Bowl in the Texas Panhandle, original date not given, processed by Capmo, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Tuesday, June 24, 2014

Kenya needs to mitigate against the causes of desertification

AllAfrica. com via the Star (Kenya): There are plans to expand land under rice irrigation in Kirinyaga County as consumption of the product continues to rise in Kenya with the current consumption rate at 300,000 tonnes annually.

Njenga Mwaura, National Irrigation Board in Mwea said the area earns Sh 3 billion per year from rice production, and small-scale farmers who largely depend on the crop stand to benefit. " There are plans to expand 800 acres of land in Kiangungu and Kiamanyeki areas and 25 hectares in Mutithi area," said Mwaura.

...National Environment Management Authority (Nema) director general, prof Geoffrey Wahungu said climate variability and extremes are a major threat to sustainable development of the county, with rising temperatures contributing to increase of malaria, erratic rainfall resulting to drying up of some rivers and also flooding especially on the lower parts of Mwea.

Wahungu added that the major contributors to the degradation of the environment in the county are deforestation, poor solid waste disposal, cultivation along river banks by the community, and pollution from industries and farmers....

Tracks in the Chalbi Desert in northern Kenya, shot by Filiberto Strazzari, Wikimedia Commons via Flickr,  under the Creative Commons Attribution 2.0 Generic license

Tuesday, June 17, 2014

UN officials call for restoration of ecosystems to reduce climate change disasters

UN News Centre: Marking the World Day to Combat Desertification, United Nations officials today emphasized the importance of restoring degrading lands to avoid or soften the potentially disastrous impacts of climate change.

“Land degradation, caused or exacerbated by climate change, is not only a danger to livelihoods, but also a threat to peace and stability,” Secretary-General Ban Ki-moon said in his message for the World Day, observed annually on 17 June.

He noted that recovering land that is degrading will have multiple benefits. “We can avert the worst effects of climate change, produce more food and ease competition over resources. We can preserve vital ecosystem services, such as water retention, which protects us from floods or droughts. And a comprehensive and large-scale approach to land recovery can create new jobs, business opportunities and livelihoods, allowing populations to not only survive, but thrive,” he stated.

The theme of this year’s World Day is “Land belongs to the future, let’s climate-proof it.” Studies show that 24 billion tons of fertile soil are being eroded each year, and 2 billion hectares of degraded land have potential for recovery and restoration.

As Member States continue efforts to elaborate a global development agenda beyond the Millennium Development Goals deadline of 2015, General Assembly President John Ashe encouraged them to work together to mitigate patterns of desertification in order to meet the daily needs of the world’s inhabitants, especially to produce food.

“Climate change can profoundly alter the relationship between water and the land. The amount and quality of the land we have today will be very different from what we will have in the future,” he said in his message....

Desertification in Namibia. Photo: UNEP/A.Gloor/Namibia

Tuesday, May 27, 2014

Recurrent floods hit desert cities

Berta Acero at the UN Office for Disaster Risk Reduction: Recurrent flooding is becoming more of a threat in the Arab region, a part of the world usually associated with drought and desertification.  At least seven people were killed, schools were forced to close and vehicles were swept away in the latest flash flooding the Saudi Arabian province of Hail.

The Head of the United Nations Office for Disaster Risk Reduction (UNISDR) in the Arab States Region, Mr. Amjad Abbashar, said urban flooding is a growing challenge in the region as well as globally.  “It is becoming more dangerous and costly because of the increasing population exposed within urban settlements. It is very important that governments manage flood risk today for a safer future through better urban management and resilient infrastructures,” Mr. Abbashar said.

“There is an urgent need to move from relief operations to preparedness and risk reduction and mitigation measures. Flood risk is a reality in the Arab region and it is very important that governments invest in flood prevention measures and an adequate land use planning.”

Flash flooding triggered by heavy downpours has claimed dozens of lives in recent years in the region with Saudi Arabia and Jordan as well as Egypt among the worst affected. The international disaster database EM-DAT recorded at least 300 flooding events between 1981 and 2011 in the region.

Major floods have been hitting Saudi Arabia recurrently since 2009, when almost twice the yearly average of rain (90mm) fell in four hours. More than 100 people were killed and economic losses were estimated at US$270 million in and around of Jeddah....

2011 flooding in Jeddah, Saudi Arabia, shot by Naif Abdullah, Wikimedia Commons via Flickr, under the Creative Commons 2.0 license 

Tuesday, April 8, 2014

Arid areas absorb unexpected amounts of carbon

Eric Sorensen in the WSU News: Researchers led by a Washington State University biologist have found that arid areas, among the biggest ecosystems on the planet, take up an unexpectedly large amount of carbon as levels of carbon dioxide increase in the atmosphere. The findings give scientists a better handle on the earth’s carbon budget – how much carbon remains in the atmosphere as CO2, contributing to global warming, and how much gets stored in the land or ocean in other carbon-containing forms.

“It has pointed out the importance of these arid ecosystems,” said R. Dave Evans, a WSU professor of biological sciences specializing in ecology and global change. “They are a major sink for atmospheric carbon dioxide, so as CO2 levels go up, they’ll increase their uptake of CO2 from the atmosphere. They’ll help take up some of that excess CO2 going into the atmosphere. They can’t take it all up, but they’ll help.”

The findings, published in the journal Nature Climate Change, come after a novel 10-year experiment in which researchers exposed plots in the Mojave Desert to elevated carbon-dioxide levels similar to those expected in 2050. The researchers then removed soil and plants down to a meter deep and measured how much carbon was absorbed. “We just dug up the whole site and measured everything,” said Evans.

...The work addresses one of the big unknowns of global warming: the degree to which land-based ecosystems absorb or release carbon dioxide as it increases in the atmosphere. ...Overall, said Evans, rising CO2 levels may increase the uptake by arid lands enough to account for 4 to 8 percent of current emissions....

The Cima Dome landscape in the Mojave National Preserve in California, shot by Stan Shebs, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 2.5 Generic license

Tuesday, January 28, 2014

A New Mexico expert seeks alternative irrigation sources to save potable landscaping water

Angela Simental at the New Mexico State University News Center: New Mexico State University Cooperative Extension Service Specialist Bernd Leinauer is a turfgrass expert, studying and researching ways to preserve green spaces in places like New Mexico, where water scarcity is a big problem. “Our research is all about water conservation. We are focusing on water preservation in the landscape,”

Leinauer said. “We need water to grow plants in the desert, but when water is used for aesthetics instead of food, for example, it becomes questionable. So, how much water can we afford to use?” Leinauer found that approximately 50 percent of potable water usage during the summer in Las Cruces goes to irrigating the landscape.

“That is true for almost any city in the desert Southwest,” he said. “Which is considered non-essential, but I would argue that it is important because when we have green space, it contributes to our well-being and moderate climate, but at the end of the day, it is a large amount of water we use for the urban landscape.”

... Leinauer said cities are taking measures to keep landscaped spaces, especially in residential areas, but reducing the outdoor and landscaped area in new housing developments, which consequently reduces the area of irrigation. A second proposed conservation strategy is to have new developments receive two water lines: one for potable water and one for non-potable, treated water for outdoor irrigation, he added.

Leinauer’s research also explores alternative irrigation sources to using potable water while maintaining safety and aesthetics. “The treated effluent a city produces should be considered an alternative source of water. It’s not potable, and so far it is just put into the river and sent to El Paso and eventually on to Mexico,” he said. This water can potentially be used for irrigation in Las Cruces since other cities such as El Paso, Albuquerque and Santa Fe use it heavily for their parks and golf courses.

...Another part of the water conservation project is investigating new and more efficient irrigation systems. Leinauer has been looking at using subsurface water to decrease the waste of water. “This way you take irrigation out of sight and below ground, therefore, you are not throwing it in the air before it has to land on the ground,” he said. “One of the reasons we use so much water during the summer, especially in the residential sector, is that irrigation systems we have in place are extremely inefficient. You see water on the sidewalk or water running down the street. That is not efficient and beneficial use.” ...

A water meter on a church in Taos, New Mexico, shot by Brian Thomas, who is releasing this glamorous image into the public domain

Friday, November 29, 2013

China desert lake shrinks by one-third in 13 years

Space Daily via AFP: China's largest desert freshwater lake has shrunk by one-third in the last 13 years, state media said Thursday, as the country's breakneck modernisation continues to damage the environment.

Northern China's Hongjiannao Lake covers 32.16 square kilometres (12.86 sq miles), less than half its size in 1969 and two-thirds of its area in 2000, Xinhua news agency said.

"Experts said human activities including reservoir construction, mining and agricultural irrigation are the main causes for the sad phenomenon," Xinhua added.

The lake, in Shaanxi province on its border with Inner Mongolia, could vanish completely in a few decades, state media has previously claimed.

China's rapid industrialisation has caused massive environmental damage and is a major source of discontent...

Saturday, October 19, 2013

First evidence that dust and sand deposits in China are controlled by rivers

Space Daily via SPX: New research published in the journal Quaternary Science Reviews has found the first evidence that large rivers control desert sands and dust in Northern China.

Northern China holds some of the world's most significant wind-blown dust deposits, known as loess. The origin of this loess-forming dust and its relationship to sand has previously been the subject of considerable debate.

The team of researchers led by Royal Holloway University, analysed individual grains of fine wind-blown dust deposited in the Chinese Loess Plateau that has formed thick deposits over the past 2.5 million years.

As part of this, they also analysed the Mu Us desert in Inner Mongolia and the Yellow River, one of the world's longest rivers, to identify links between the dust deposits and nearby deserts and rivers.

The results showed that the Yellow River transports large quantities of sediment from northern Tibet to the Mu Us desert and further suggests that the river contributes a significant volume of material to the Loess Plateau....

The Gobi Desert, Inner Mongolia, shot by Svdmolen, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Tuesday, September 24, 2013

UN ready to assist Namibia mitigate drought

AllAfrica.com via the Namibian: The United Nations Secretary-General Ban Ki-moon announced yesterday that the UN is ready to support Namibia fight the effects of the drought that is currently ravaging Namibia. In a message to the 11th Conference of Parties to the parties of the United Nations Convention to Combat Desertification yesterday, Ki-moon said the conference was taking place at a time Namibia is facing a severe drought.

"You meet as Namibia faces severe drought. The United Nations system stands ready to continue to support your efforts to mitigate its effects and build resilience. Desertification and land degradation threaten the livelihoods, well-being and sustainable development of at least one billion people.

In the drylands of Africa, climate change is already having an impact. Temperatures have risen by about two degrees Celsius in some areas. Long periods of drought, famine and deepening poverty are impoverishing and depopulating vast areas," he said.

He said healthy land is a prerequisite for food and water security and necessary to avert political instability. "We need it for climate change resilience and preserving valuable biodiversity. World leaders at Rio+20 acknowledged the threat of desertification, land degradation and drought in all regions, and especially for developing countries. As we define the post-2015 development agenda, we need to be able to measure progress towards the commitment to halt and reverse land degradation," he said...

The Fish River Canyon in Namibia, shot by GIRAUD Patrick, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Wednesday, September 11, 2013

Massive water discovery in Kenya's desert

Paula Kahumba in the "Africa Wild" blog at the Guardian (UK): UNESCO and the Kenya Government today announce the discovery of one of the worlds largest underground water aquifers in the desert north of Turkana, an area best known for fossils, famine and poverty. The finding by Radar Technologies International (RTI) was made using space based exploration technology called WATEX system. The largest aquifer at 250 billion cubic meters of water which is equivalent in volume to Lake Turkana one of the largest lakes in the Great Rift Valley, and 25 times greater than Loch Ness. More importantly the annual recharge rate, the amount of water that can be sustainably exploited per year, is estimated to 3.4 billion cubic meters, nearly three times the water use in the New York City.

The man behind the RTI is the energetic white haired French Alain Gachet who says the worst thing he has ever seen in his life is people dying of thirst. "This discovery will transform Turkana. In 10 years time I see no more suffering, no more dying of hunger or thirst, people will have schools, roads, farms. Life will be much better for them and famine will be a thing go the past".

For Turkana where malnutrition rates can be as high as 37%, this discovery Is better than oil. It is an opportunity for local development. Ikal Angelei is the Director of Friends of Lake Turkana, an organzation that champions the rights of the Lake's communities and ensure their involvement in decision-making on issues relating to the Lake and its environment.

"This is an extremely exciting find for my community. While we celebrate however, we must be wise. The first thing we must do is confirm the recharge rate so that we do not kill the golden goose, and we must also protect against speculators and unscrupulous people who threaten to take it away from the local communities. The Kenyan leadership must plan carefully to ensure that in developing the resource we protect and respect the rights and the needs of local communities who must benefit."...

The town of Kalokol in the Turkana Desert, shot by Mr.matija.kovac, Wikimedia Commons,  under the Creative Commons Attribution-Share Alike 3.0 Unported license

Tuesday, August 27, 2013

Plantations in Africa's deserts could help capture carbon

Nehal Lasheen and Imogen Mathers in SciDev.net: Planting trees in coastal deserts could capture carbon dioxide, reduce harsh desert temperatures, boost rainfall, revitalise soils and produce cheap biofuels, say scientists.

Large-scale plantations of the hardy jatropha tree, Jatropha curcas, could help sequester carbon dioxide through a process known as 'carbon farming', according to a study based on data gathered in Mexico and Oman that was published in Earth System Dynamics last month (31 July).

Each hectare of the tree could soak up 17-25 tonnes of carbon dioxide a year, they say, at a cost of 42-63 euros (about US$56-84) per tonne of gas, the paper says. This makes the technique competitive with high-tech carbon capture and storage.

Klaus Becker, the study's lead author and director of carbon sequestration consultancy Atmosphere Protect, says that a jatropha plantation covering just three per cent of the Arabian Desert could absorb all the carbon dioxide produced by cars in Germany over two decades.

"Our models show that, because of plantations, average desert temperatures go down by 1.1 degree Celsius, which is a lot," Becker says. He adds that the plantations would also induce rainfall in desert areas...

Jatropha planted in Senegal, shot by Trees ForTheFuture, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license

Wednesday, August 7, 2013

Could planting trees in the desert mitigate climate change?

A press release from the European Geosciences Union: As the world starts feeling the effects of increasing atmospheric carbon dioxide and consequent global temperature rise, researchers are looking for a Plan B to mitigate climate change. A group of German scientists has now come up with an environmentally friendly method that they say could do just that. The technique, dubbed carbon farming, consists in planting trees in arid regions on a large scale to capture CO2. They publish their study today in Earth System Dynamics, a journal of the European Geosciences Union (EGU).

“Carbon farming addresses the root source of climate change: the emission of carbon dioxide by human activities,” says first-author Klaus Becker of the University of Hohenheim in Stuttgart. “Nature does it better,” adds Becker’s colleague Volker Wulfmeyer, “if we understand and can make use of it in a sustainable manner.”

When it comes to sequestering carbon from the atmosphere, the team shows that Jatropha curcas does it better. This small tree is very resistant to aridity so it can be planted in hot and dry land in soil unsuitable for food production. The plant does need water to grow though, so coastal areas where desalinated seawater can be made available are ideal.

“To our knowledge, this is the first time experts in irrigation, desalination, carbon sequestration, economics and atmospheric sciences have come together to analyse the feasibility of a large-scale plantation to capture carbon dioxide in a comprehensive manner. We did this by applying a series of computer models and using data from Jatropha curcas plantations in Egypt, India and Madagascar,” says Wulfmeyer.

...“From our point of view, afforestation as a geoengineering option for carbon sequestration is the most efficient and environmentally safe approach for climate change mitigation. Vegetation has played a key role in the global carbon cycle for millions of years, in contrast to many technical and very expensive geoengineering techniques,” explains Becker...

Processes involved in carbon farming (Credit: Becker et al. 2013)

Thursday, July 4, 2013

Africa’s tiny ‘sand dams’ can save millions from drought

Nilima Choudhury in Responding to Climate Change: Water-related diseases kill more than 3.5 million people every year – particularly in dryland regions of the world, making the ability to store and harness water crucial. Rising global temperatures are aggravating the effects of climate change creating more erratic weather leading to heavy rainfalls and drought.

The 2011 drought and the resulting famine in East Africa killed 100,000 people and sent food prices soaring. But reversing the devastating effects of climate change is possible. Sand dams can offer a cost-effective and sustainable solution to mitigating the impacts of climate change, the desertification of drylands and enabling green economic growth in dryland countries.

Drylands are home to more than one third of the global population, and make up 44% of all the world’s cultivated systems and account for 50% of its livestock. Local communities have teamed up with NGOs and the UN to build sand dams, concrete walls built across riverbeds, to combat environmental degradation and desertification that destroys wildlife and habitats.

In Kenya, the Africa Sand Dam Foundation and UK-based NGO Excellent Development work to empower marginalised rural communities to transform their environment for the sustainable and mutubenefit of the local ecosystem and people. They support communities to gain access to clean water for improved food security, health and income...

A sand dam, shot by angrahamneal, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Monday, June 17, 2013

Behind the rhetoric what is really being done to combat desertification?

Gavin Haines in the Independent (UK): Like most people living along the Sahel – the drylands between Africa’s tropical savannahs and the Sahara Desert – Mustafa Ba is all too familiar with the effects of desertification. Thanks to a combination of overgrazing and deforestation, he has watched the countryside around his Senegalese village, Mboula, turn into a dusty, unproductive wasteland.

“Trees provide us with many benefits,” explains Mustafa, as we sit on a mat in the centre of his village. “They are good for the soil and important for food security.” But in impoverished regions of rural Africa, selling firewood is a source of quick cash and many trees along the Sahel have been felled. Communities have paid a high price for such enterprise; with no trees to protect the land, vast swathes of the Sahel have succumbed to desertification.

According to the United Nations, Mustafa is one of 850 million people – nearly one eighth of the global population – to be directly affected by this process of land degradation. But it’s not just a local problem; desertification has an impact on food production, which pushes up grocery bills around the world (the UN estimates Guatemala alone loses 24 per cent of its agricultural GDP due to desertification). 

To raise awareness of the issue, the UN reserved June 17 as World Day to Combat Desertification, but behind the rhetoric it has also been supporting projects to tackle the phenomenon head on. One of those is Great Green Wall of Africa, a 4,800-mile “wall” of trees that is being planted across the continent between Senegal and Djibouti....

A desert encampment at Lompoul, Senegal, shot by G.No, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license 

Wednesday, April 17, 2013

Desertification crisis affecting 168 countries worldwide, study shows


Ed King in the Guardian Environment Network via Responding to Climate Change: Severe land degradation is now affecting 168 countries across the world, according to new research released by the UN Desertification Convention (UNCCD).

The figure, based on submissions from countries to the UN, is a marked increase on the last analysis in the mid-1990s, which estimated 110 states were at risk.

In an economic analysis published last week the Convention also warns land degradation is now costing US$490 billion per year and wiping out an area three times the size of Switzerland on an annual basis.

"Land degradation and drought are impeding the development of all nations in the world," UNCCD Executive Secretary Luc Gnacadja told RTCC.

"This is a challenge that is causing governments to take this issue seriously, but how do you get them to take it seriously? By showing them the rate of return on restoring degraded land is one of the smartest investments of our time.

He added: "Desertification, land degradation and drought is an issue of market failure. The lack of economic market valuation has led to land being perceived as a cheap resource." ...

Photo by Ubub92, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Saturday, April 13, 2013

Data dearth impeding fight against desertification

Jan Piotrowski in SciDev.net: The lack of location-specific scientific data on the degradation of land, and the dearth of networks through which to share such data where it does exist, are hampering the fight against desertification, a conference has heard.

The absence of such data means that the global models that map land degradation and are used in policy and funding decisions misrepresent the situation in many regions, particularly in developing countries, heard the UN Convention to Combat Desertification's (UNCCD) 2nd Scientific Conference in Bonn this week (9-12 April).

Klaus Kellner, South Africa's science and technology correspondent to the UNCCD, tells SciDev.Net that the World Atlas of Desertification, as well as similar maps for climate change and biodiversity, understate the severity of the situation as a result.

For example, a model presented to the conference indicated only minimal land degradation in the Sahel — a claim contradicted by scientists from the African region who attended the event, he says. "These global maps often overlook areas that have a lack of data, which are often the poorest and most in need," he adds.

The effect of land degradation, especially in the developing world, is significant, according to a UNCCD report, presented at the conference. Africa's agricultural GDP is reduced by four to 12 per cent because of environmental damage, the vast majority of which is due to land degradation, the study estimates. In Guatemala, this figure rises to 24 per cent, it adds.

Yet despite these impacts, inaccurate mapping can lead policymakers to underestimate some areas' vulnerability to land degradation, says Kellner...

Australia's Great Sandy Desert, from NASA. This is a false-color composite image made using shortwave-infrared, infrared, and red wavelengths.

Tuesday, April 2, 2013

Holy land underwater -- a Carbon Based original

    For Easter, the TV schedule teemed with biblical epics (although no Life of Brian -- how odd). The procession included one of the most intelligent and thoughtful examples of the genre -- The Greatest Story Ever Told, directed by George Stevens, with Max von Sydow as Jesus, his hair dyed black. I'd seen it before, and been impressed with its virtues and willing to forgive its flaws. 

    Sure, the Hollywood piety and celestial choruses are grating. Too many of these middle eastern Jews are blond and speak with plummy British accents.  The pace stretches out much too long, especially for us nonbelievers.  Von Sydow struggles bravely to breathe some life into his Gospel-only solemnities. Everybody laughs at John Wayne's line reading as the centurion at the foot of the cross. 

    But many of the performances are superb.  Donald Pleasance portrays Satan as an ineffectual geezer who doesn't have much heart for tempting Jesus, but turns powerful and malevolent when inciting a crowd or steering Jesus to his fate.  Claude Rains does a memorably creepy rendition of Herod doddering on his throne as he orders the death of children.  Charlton Heston devours his role as John the Baptist, and was rightly proud of it.

    But what interests me most are the locations, beautifully shot by Loyal Griggs and William C. Mellor, in Southern Utah near the Glen Canyon Dam in Page, Arizona.  The message board on the film at the Internet Movie Data Base contains several sniffs that the Utah desert is much dryer than the ancient Palestine, which is certainly true, but irrelevant. These desert vistas are otherworldly, some of them of a scale and significance that you might wonder why you haven't seen them before. 

    The reason is, many of them no longer exist. The locations vanished not because of climate change, but as a result of human decisions. Weeks before the filming of the Greatest Story in March of 1963, the gates of the Glen Canyon dam closed, trapping the river.   Many of the locations would soon vanish under Lake Powell.

    A major environmental controversy swirled around that dam. David Brower, head of the Sierra Club, battled the Bureau of Reclamation's plans to contain the Colorado River. The Club argued that the dam would destroy a unique wilderness, and set ominous precedent for plundering America's protected lands.

    In the mid-1950s, the Bureau of Reclamation agreed to forego two other dams, but only if they could proceed unopposed with dams at Flaming Gorge and Glen Canyon. The Sierra Club agreed. Congress authorized the Colorado River Storage Project in April 1956, and groundbreaking for the Glen Canyon followed quickly. 

    At first, many celebrated this outcome a major victory for the American environmentalists -- after all, they'd stopped two dams. But in a few months Brower regretted the Sierra Club's compromise.  With the dam under construction, he traveled down the Colorado River and was shocked by the beauty and grandeur of the landscape he had consigned to submersion.  Brower later wrote, "Glen Canyon died, and I was partly responsible for its needless death. ... Neither you nor I, nor anyone else, knew it well enough to insist that at all costs it should endure. When we began to find out it was too late."

    In the Sierra Club's magazine in 2000, he reflected, "But as surely as we made a mistake years ago, we can reverse it now. We can drain Lake Powell and let the Colorado River run through the dam that created it, bringing Glen Canyon and the wonder of its side canyons back to life. We can let the river do what it needs to do downstream in the Grand Canyon itself."

    In addition to the loss of a landscape and an ecosystem, the environmentalist objections stressed the inefficient water use the dam made of the Colorado River.  The larger the size of Lake Powell, the greater the volume of water lost to evaporation.  "Draining Lake Powell means more water for the Colorado River states and Mexico, especially Colorado and Utah. The hundreds of millions of dollars now being lost, growing to billions in the future, should be enough to give even Bill Gates pause," Brower said. " ... The sooner we begin, the sooner lost paradises will begin to recover."

    The Glen Canyon Dam still stands, but Brower's counterintuitive strictures against dams are especially relevant for the parched Southwest, where larger reservoirs result in more water loss.  The Southwest needs the water more than ever. 

    But even if we make only correct decisions, the long-range outcome will probably be the same.  We'll need to move people out of the desert.

    I suspect that a number of decisions we make about climate change are going to follow this pattern -- environmentalists will support or oppose a project, based on their knowledge at the time, only to discover something later that makes them change their mind.  Long-range impacts are impossible to gauge, even for high-status glamour projects, such as building dams.  And once we reach that point where we know the consequences, it will probably be too late.  To add to the sting, there won't be a biblical movie being filmed to inadvertently document what we're going to lose.

    In the moment we make our decisions, we never know the ultimate outcome. At the George Stevens version of the last supper, getting exasperated with the gnomic utterances, one of the disciples says, "Speak plainly and speak no proverbs."  Good luck to anyone trying to wangle a straight answer out of Jesus, or out of the future -- we won't know the meaning until much later, when the waters are rising.

Paria, Utah, where other moviews were filmed, but not The Greatest Story Ever Told. Shot by John Fowler, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license

Tuesday, February 12, 2013

Fog-catching fabric could improve water collection in deserts

Joel Winston in SciDev.net:  A novel and affordable fabric may improve the efficiency of water collection from fog, helping to provide freshwater in desert areas. Researchers from the Eindhoven University of Technology (EUT), in the Netherlands, and Hong Kong Polytechnic University, China, turned a  cotton fabric into a water-collecting material by coating it with a polymer called PNIPAAm.

The fabric switches between absorbing moisture directly from the air when it is foggy and cold, and releasing it as water at warmer temperatures, according to a paper to be published on 21 February in Advanced Materials.

Every kilogramme of the sponge-like fabric can absorb around 3.4 litres of water from the air.  When the ambient temperature rises, the material's microstructure changes and the water is released. These processes are repeatable, raising hopes the fabric could act as an autonomous water-collecting device.

The team hopes the material could be used to harvest water in dry coastal areas, such as the Namib Desert, in Namibia, where rainfall is scarce but ocean air currents frequently bring vapour-carrying fogs.

The temperature range within which the fabric collects, and then releases, water is similar to the typical daytime highs and night-time lows seen in deserts....

A dune in the Namib Desert, shot by Teo Gómez, who has released it into the public domain

Tuesday, November 6, 2012

Lake Aibi shrinks as desertification rises

Terra Daily via UPI: China faces a losing battle to restore Lake Aibi's ecosystem due to worsening desertification in the region of the salt lake, officials say. The large lake in northwestern China's Gobi region sits in an internally draining, salt-rich basin near the border of Xinjiang-Uighur province and Kazakhstan. It has been shrinking at more than 15 square miles a year because of encroaching desert.

Officials said about 580 square miles of the lake have dried up and its size has been reduced to less than 193 square miles, the Xinhua News Agency reported Saturday. Excessive land reclamation and flood irrigation are only adding to the problem. The dry earth left on the lake bed is frequently whipped up into sandstorms that plague China's northern regions every year, Xinhua reported.

The problem has not been solved despite efforts to restore the area's ecosystem in the past decade, said Gao Xiang, head of the Lake Aibi wetland reserve administration. The national wetland nature reserve covers an area of 1,030 square miles. Gao said the dried-up lake bed will become part of Mutetar Desert in four years without effective measures....

NASA image of Lake Aibi

Tuesday, September 18, 2012

Putting up a green shield against the Mongolian desert

Manipadma Jena in IPS: ...Lianjun’s half hectare of farmland sports neat spaced-out rows of maize crops, as in that of Hua Limei, his neighbouring farm owner, and most others on that stretch. “We earn around 400 yuans (63 dollars) from each harvested mu (15mu equals one hectare),” Limei tells IPS.

...It’s hard to believe that these farmlands and Taipingdi township were harsh sandy deserts just 60 years back. At that time, less than 66 hectares of forest were edged in by 4,500 sand dunes. Lianjun’s grandfather barely eked out a fourth of what he harvests today. Today deep forest belts shelter 10,000 hectares of Taipingdi farmland.

...As the sand progressively degrades the farmland, growing poverty creates a vicious cycle. “The poorer the farmer, the more he’s desperate to get from the land. Consequently over-farming leads to worse degradation and he loses more than he gains,” 34-year old BaoYongxin, an activist farmer from Aohan county tells IPS in Chifeng city.

...At the forest department training centre they were told about various conversion methods: covering the shifting sands with a plastic net; chemical treatment to bind the surface sand; and containing sand mobility by regular interval fencing with shrubs, stone and straw.

The Aohan community chose a combination of mechanical and biological measures to re-vegetate and reforest its land. The checker board method, after the dunes had been somewhat leveled by machine, was to draw three-feet squares that were then closely barricaded by 25 cm lengths of straw with half of their length secured into the sand....

A potato harvest in Mongolia, USAID photo