by Alok Jha
This crisis is being driven partly by climate change, as rising temperatures lead to drier soils and less rainfall in many parts of the world. But there is the added pressure of increasing populations too, wrote Nature. “As nations such as India and China grow more prosperous, for example, their citizens are switching to more protein-rich Western diets. It takes some 15,500 litres of water to produce a kilogram of industrial beef, ten times as much as is needed to produce 1 kilogram of wheat. These nations are likewise shifting their energy consumption towards intensities common in the developed world.”
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WATER DEPRIVATION
1 billion people have no safe drinking water
Over 2 billion are without sanitation
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The United States uses 500 billion liters of fresh water per day, around 40 percent of its freshwater use, for cooling electric power plants. The country uses the same again for irrigation. “The resulting pressures on water supplies are unrelenting. Global energy demand is projected to increase 57% by 2030, and water demand for food production might easily double,” says Nature. “By 2050, feeding the world’s growing population may require some 3,000 cubic miles of water—the volume of Lake Superior—every year. Yet many of the world’s rivers and lakes are already dramatically overused: China’s Yellow River doesn’t always reach the ocean, and Lake Mead in the American southwest could be dry by 2021 if water usage is not curtailed.”
In 2005, the United Nations reported that by 2050, more than 4 billion people would be living in nations defined as water-scarce or water-stressed, up from half a billion in 1995. A year later, the International Water Management Institute conducted a study showing that a third of the world’s population was already living in water-scarce areas. When the same team had carried out the same analysis six years earlier, they had predicted that such a situation would not occur until 2025.
The IPCC’s verdict on the effects of climate change on global water supply is also stark. “Globally, the negative impacts of future climate change on freshwater systems are expected to outweigh the benefits,” it said. “By the 2050s, the area of land subject to increasing water stress due to climate change is projected to be more than double that with decreasing water stress. Areas in which runoff is projected to decline face a clear reduction in the value of the services provided by water resources. Increased annual runoff in some areas is projected to lead to increased total water supply. However, in many regions, this benefit is likely to be counterbalanced by the negative effects of increased precipitation variability and seasonal runoff shifts in water supply, water quality and flood risks.”
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Extreme droughts will become ever more common, contributing to the disappearance of vast swathes of vegetation.
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Climate models for the rest of this century show that, because of global temperature increases due to greenhouse gas emissions, precipitation will increase in high latitudes and parts of the tropics, but will decrease in subtropical and lower mid-latitude regions, including the Mediterranean basin, the western USA, southern Africa and north-eastern Brazil. Extreme droughts will become ever more common, contributing to the disappearance of vast swathes of vegetation—in some scenarios, extreme drought will increase from one percent of present-day land area to 30 percent by 2100.
Which areas are under stress?
By 2025, nine countries in the eastern and southern parts of Africa will have only 1,000 cubic meters of water available per person per year. Twelve further countries on the continent will be limited to 1,000–1,700 cubic meters per year, and the population at risk of water stress could rise to 460 million, mainly in western Africa. “In addition, one estimate shows the proportion of the African population at risk of water stress and scarcity increasing from 47% in 2000 to 65% in 2025,” said the IPCC in its 2008 report on climate change and water. “This could generate conflicts over water, particularly in arid and semiarid regions.”
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Someday we might look back with a curious nostalgia at the days when profligate homeowners wastefully sprayed their lawns with liquid gold to make the grass grow, just so they could then burn black gold to cut it down on the weekends.
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Around the Mekong Delta in Vietnam, a doubling of CO2 in the atmosphere will cause enough climate change to trigger severe flooding in the wet season and the risk of extreme drought in the dry season.
Water availability in India is projected to decline from about 1,820 cubic meters per year per person in 2001 to 1,140 cubic meters per year in 2050, as a result of population growth alone. However, a more pessimistic scenario has India reaching a state of water stress before 2025, when the availability is projected to fall below 1,000 cubic meters per person, according to the IPCC, due to climatic and demographic factors.
In South America, the number of people living in water-stressed environments (in other words, with supplies of less than 1,000 cubic meters per person per year) in the absence of climate change was estimated at 22.2 million in 1995. This number is expected to increase to between 12 and 81 million in the 2020s and to between 79 and 178 million in the 2050s.
The decline is visible everywhere. In 1940, the Chacaltaya glacier in Bolivia measured 0.22 km2; by 2005, this had reduced to less than 0.01 km2. Over the period 1992 to 2005, the glacier suffered a loss of 90 percent of its surface area, and 97 percent of its volume of ice.
As well as the problems described above, lack of fresh water is also a risk factor for bad health. “Childhood mortality and morbidity due to diarrhoea in low-income countries, especially in sub-Saharan Africa, remains high despite improvements in care and the use of oral rehydration therapy,” says the IPCC. “Climate change is expected to increase water scarcity, but it is difficult to assess what this means at the household level for the availability of water, and therefore for health and hygiene.”
What can we do?
Quite a lot, as it happens—the potential for savings, without hurting human health or economic productivity, is vast. “Improvements in water-use efficiency are possible in every sector. More food can be grown with less water (and less water contamination) by shifting from conventional flood irrigation to drip and precision sprinklers, along with more accurately monitoring and managing soil moisture,” says Peter H. Gleick, president of the Pacific Institute, writing in Scientific American. “Conventional power plants can change from water cooling to dry cooling, and more energy can be generated by sources that use extremely little water, such as photovoltaics and wind. Domestically, millions of people can replace water-inefficient appliances with efficient ones, notably washing machines, toilets and showerheads.”
According to Nature, the key to tackling the crisis in the most food-insecure parts of the world is to manage so-called “green water,” the abundant moisture that infiltrates the soil from rainfall, and that can be taken up by the roots of plants. “Experts estimate that in regions such as sub-Saharan Africa, where more than 95% of crops are rain-fed, only 10–30% of the available rainfall is being used in a productive way. The fixes they suggest are decidedly low-tech: harvesting rainwater, planting roots deeper, better terracing, and switching from ploughing to tilling. Yet the potential gains could be enormous. In heavily irrigated regions such as south Asia, meanwhile, equally simple improvements in water usage could take the pressure off precious blue-water supplies, and hence drinking water.”
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In regions such as sub-Saharan Africa, where more than 95% of crops are rain-fed, only 10–30% of the available rainfall is being used in a productive way.
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The biggest change, though, must be in the way we view water. No longer should it be seen as a free, limitless resource that falls from the skies and fills seas and rivers ready for our exploitation. Perhaps then we might use it more thoughtfully, so that in future there will be more to go around.
Resource Depletion
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The raw ma
terials that keep 21st century life moving and communicating are largely invisible. Forget the stone, iron and fire of previous generations, today we depend on a set of materials from the most unfamiliar reaches of the periodic table of elements. Without them, we would not have electronics or drugs or plastics. And they are running out.
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You know that your computer is made of plastic and aluminum or steel, but deep inside, there are minute traces of more curious elements. These elements make magnets stronger, so that your hard disk can be smaller; they make lasers more powerful and reliable so that they can be used everywhere with ease; and they speed up industrial chemical reactions so that the products we need are cheaper and easily available. Without these elements, modern society would not exist.
How bad is the problem?
Ever since the Industrial Revolution, the demand for raw materials has been shooting up. John E. Tilton, a mineral economist at the Colorado School of Mines, reckons that humans have used up more aluminum, copper, iron, steel, phosphate rock, sulfur, coal, oil, natural gas, and even sand and gravel over the past century than during all earlier centuries put together. Without this stuff, he says, modern life would be hard to imagine. And the pace of consumption is only getting faster.
Jared Diamond, a professor of geography at the University of California, Los Angeles, and author of Collapse and Guns, Germs, and Steel, estimates that the average rate at which people consume resources such as oil and metals, and produce waste including plastics and greenhouse gases, is about 32 times higher in North America, western Europe, Japan and Australia than it is in the developing world.
The world’s fastest-growing economy, China, which has a population of 1.3 billion people, has started to consume at Western levels; if this continues, the world will run out sooner rather than later. “Per capita consumption rates in China are still about 11 times below ours, but let’s suppose they rise to [US] levels,” wrote Diamond in The New York Times. “Let’s also make things easy by imagining that nothing else happens to increase world consumption—that is, no other country increases its consumption, all national populations (including China’s) remain unchanged and immigration ceases. China’s catching up alone would roughly double world consumption rates. Oil consumption would increase by 106 per cent, for instance, and world metal consumption by 94 per cent.”
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This stuff, most of it from the lower, unfamiliar reaches of the periodic table of elements, is what makes modern society tick. And it is running out.
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If the calculations included India as well as China, global consumption rates would triple. “If the whole developing world were suddenly to catch up, world rates would increase elevenfold,” says Diamond. “It would be as if the world population ballooned to 72 billion people.”
The question of resource depletion is not concerned with the things you might normally hear about—oil, for example—but rather with the stuff that underpins our hi-tech world. The idea of “materials security” has become a prominent issue in the first decade of the 21st century.
Take helium, the second most abundant element in the universe. Its two stable isotopes, helium-3 and helium-4, are essential components in cryogenic technology. If you need a superconducting magnet, its temperature will have to be dropped to within a few degrees of absolute zero (-273.15°C), and for this you require supercooled helium. But even as use of this element is on the rise, the price has been kept artificially low by the US government, which controls the US National Helium Reserve near Amarillo, Texas. According to Nobel laureate Robert Richardson, who discovered some of liquid helium’s more unusual properties, “the world would run out in 25 years, plus or minus five years.”
An analysis by the Öko-Institut, funded by the United Nations and the European Union, highlighted several metals that will be needed for sustainable technologies of the future. These include tantalum, indium, ruthenium, gallium, germanium, cobalt, lithium, platinum and palladium for “green” electronics, solar cells and batteries.
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The question of resource depletion is not concerned with the things you might normally hear about—oil, for example—but rather with the stuff that underpins our hi-tech world.
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Exact information about how much of these critical elements there is in the world is often difficult to establish, subject to the secrecy of mining companies and metal traders. But it is clear that they are not infinite, and it is clear too that they will run out as the world’s population develops.
And then there’s the rare earth elements ...
“Throughout history, political fights and international wars have often been waged over securing valuable resources such as oil, water and food,” declared a December 2010 editorial in the journal Nature Photonics. “Now, a group of 17 elements in the periodic table known collectively as the ‘rare earths’ (named so because they were first found within rare minerals buried deep underground) are at the centre of a political storm that threatens the photonics industry.”
The importance of these elements might not be immediately obvious, but our lives would not be the same without them, continued the editors of the journal. “Elements such as erbium, ytterbium, yttrium, neodymium, thulium and europium are vital optically active ingredients at the heart of many lasers, optical amplifiers and phosphors. Put simply, rare earths transform otherwise benign crystals, glass fibers and thin films into materials that are capable of emitting and amplifying light.”
In other words, rare earth elements are essential components of the lasers that we now see everywhere, from supermarket checkouts to spacecraft. Beyond that, they are also used in magnets, batteries and lightweight metal alloys. Their specific chemical and physical properties make them useful in improving the performance of computer hard drives, catalytic converters, mobile phones, hi-tech televisions and sunglasses.
As technology advances, so the demand for the metals rises; in the past decade, their use has doubled. There are several kilograms of such elements in typical hybrid petrol-electric cars made by Toyota and Honda, a market that will expand in coming years.
Despite their name, rare earth elements are not actually all that rare. In a report published in 2010, the British Geological Survey put their natural abundance on the same level as copper or lead. The problem is access and supply: China has a nearmonopoly on mining these elements. It owns 37 percent of the world’s estimated reserves, about 36 million tons, but controls more than 97 percent of production. The former Soviet bloc has around 19 million tons and the US 13 million, with other large deposits held by Australia, India, Brazil and Malaysia.
The US House of Representatives is so worried about security of supply that it is considering legislation to try to end America’s dependence on Chinese imports. The Mountain Pass mine in California, shut down in 2002 because of environmental and cost issues, is now to be reopened, along with potential mines at Bear Lodge in Wyoming and Bokan Mountain in Alaska.
Other sources, untapped as yet, include Greenland, which estimates suggest could meet 25 percent of global demand for rare earth elements. South Africa also has potential for rich deposits, as do Malawi, Madagascar and Kenya.
What could happen?
Jared Diamond warns that the imbalance in general consumption between the developed and developing worlds will lead to trouble. “People in the third world are aware of this difference in per capita consumption, although most of them couldn’t specify that it’s by a factor of 32,” he wrote in The New York Times. “When they believe their chances of catching up to be hopeless, they sometimes get frustrated and angry, and some become terrorists, or tolerate or support terrorists. Since September 11, 2001, it has become clear that the oceans that once protected the United States no longer do so. There will be more terrorist attacks against us and Europe, and perhaps against Japan and Australia, as long as that factorial difference of 32 in consumption rates persists.
“People who consume little
want to enjoy the high-consumption lifestyle. Governments of developing countries make an increase in living standards a primary goal of national policy. And tens of millions of people in the developing world seek the first-world lifestyle on their own, by emigrating, especially to the United States and Western Europe, Japan and Australia. Each such transfer of a person to a high-consumption country raises world consumption rates, even though most immigrants don’t succeed immediately in multiplying their consumption by 32.”
What can we do?
No atoms are destroyed when they are incorporated into appliances or used in industry (though helium is leached from the atmosphere into space). In theory, even the rarest elements can be recycled, but sometimes they can become so dispersed as to render them almost unobtainable.
Worldwide, more than 400 million tons of metal is recycled each year. Japan’s National Institute for Materials Science believes its scientists can go further in extracting value from the country’s discarded hi-tech gadgets: it has estimated that there is around 6,800 tons of gold (16 percent of the world’s reserves), 60,000 tons of silver (22 percent) and 1,700 tons of indium (15.5 percent) in Japanese “urban mines.”
