Water scarcity affects every continent and more than 40% of the global population. There is sufficient fresh water but due to bad economics and poor infrastructure, millions die each year from diseases associated with inadequate water supply, sanitation and hygiene. Many river basins experience water scarcity and are over-drained, hampering critical ecosystem functions. Some 2.7 billion people suffer water shortage for at least one month a year. There's a lot of water on the planet we inhabit - an estimated 326 million trillion gallons or 1,260,000,000,000,000,000,000 liters.
That makes it hard to believe that there are somewhere between 780 million to one billion people without basic and reliable water supplies and that more than two billion people lack the requirements for basic sanitation. Harder still to believe are reports water is going to get much dearer in our near term future - yet Peter Voser the chief executive of the world's second-largest energy company, Royal Dutch Shell, warned in June 2011, that global demand for fresh water may outstrip supply by as much as 40 per cent in 20 years if current fresh-water consumption trends continue.
Our planet is 70 percent covered in ocean, ninety-eight percent of the world's water is in the oceans - which makes it unfit for drinking or irrigation because of salt. Just two percent of the world's water is fresh, but the vast majority of our fresh water, 1.6 percent, is in its frozen state and locked up in the polar ice caps and glaciers. Our available freshwater (.396 percent of total supply) is found underground in aquifers and wells (0.36 percent) and the rest of our readily available fresh water, 0.036 percent, is found in lakes and rivers.
Freshwater aquifers are one of the most important natural resources in the world today, but in recent decades the rate at which we're pumping them dry has more than doubled. The amount of water pumped has gone from 126 to 283 cubic kilometers per year - if water was pumped as rapidly from the Great Lakes they would be dry in roughly 80 years. Another effect of over pumping is saltwater intrusion. If too much groundwater is pumped out from coastal aquifers saltwater may flow into them causing contamination of the aquifer. A growing number of rivers do not make it to the sea. Streams, rivers and lakes are almost always closely connected with an aquifer. The depletion of aquifers doesn't allow these surface waters to be recharged - lowering water levels in aquifers is being reflected in reduced amounts of water flowing at the surface. This is happening along the Atlantic Coastal Plain, groundwater depletion is also responsible for the Yellow River in China not reaching the ocean for months at a time, the failure of the Colorado River in the U.S. and the Indus River in Pakistan failing to reach the ocean every day. Over the past twenty years, a catastrophic 55 % drop in flow of water was recorded in the drought-plagued valley of Africa’s 3rd largest river, the Niger, which is expected to shrink considerably by the year 2040. As the closest major source of potable water to the Sahara Desert, the Niger water is a key source of survival for ecosystems, life and the socio-economic development of an area severely stricken by drought and famine. There is widespread surface and groundwater contamination that makes valuable water supplies unfit for other uses.
California and Texas account for much of America's food production. California's Central Valley is sometimes called the nation's "fruit and vegetable basket." The High Plains, which run from northwest Texas to southern Wyoming and South Dakota, are sometimes called the country's "grain basket." They also account for half of all groundwater depletion in the U.S., mainly as a result of irrigating crops. During the recent drought in California's Central Valley, from 2006 to 2009, farmers in the south depleted enough groundwater to fill the nation's largest man-made reservoir, Lake Mead near Las Vegas—a level of groundwater depletion that is unsustainable at current recharge rates. And researchers project that if current trends continue some parts of the southern High Plains that currently support irrigated agriculture, mostly in the Texas Panhandle and western Kansas, will be unable to do so within a few decades.
The Food and Agriculture Organisation says one in seven people suffer from malnourishment. About one-third of the world food production for human consumption - some 1.3 billion tonnes - are lost and wasted each year. We have to rethink how we grow, share and consume our food. Arable land covers just three percent of the world's surface. Based on historical data arable land decreases by 25 million acres annually - it is estimated that one hectare (one hectare equals 2.47 acres) of productive land is lost every 7.67 seconds. The greatest causes of lost productive land are desertification and urbanization. Desertification - new deserts are growing at a rate of 51,800 square kilometers per year. There is an urgent need for decision makers both local and international, to take action and reduce the spread of soil erosion and the intense desertification in the Sahel region. As an example Nigeria (Africa's most populous country) is losing almost 900,000 acres of cropland per year to desertification because of increased livestock foraging and human needs. The past few decades have been warmer than any other comparable period for the last 400 years. Limiting the global average warming to 2°C above pre-industrial levels will require hefty emission cuts of over 80%. If that does not happen, most parts of the world will see a temperature hike of above 2°C annually by 2040. Urbanization - The change of diet among newly prosperous, urban populations in developing countries is the most important factor stoking the rise in global food demand. The world’s cities occupy just 2% of the planet, but account for 60% to 80% of energy consumption. cities the world over are plagued by numerous problems such as congestion, inadequate housing, declining infrastructure, pollution, poverty and water shortages.
The world's options for increasing food production are limited by the supply of land and water. We must a) place more of the world's land under cultivation or b) increase yields on existing usable land or c) both of the above.
We are going to have to grow more food. To do that we need to increase yields on our arable land and find more fresh water for irrigation. The question we should be asking is whether capitalism can achieve and sustain the enormous harvest we need from this planet to feed ourselves.
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