Rivers such as the Nile, the Jordan, the Yangtze and the Ganges are not only overtaxed, they also now regularly peter out for long periods during the year. Providing adequate water is especially challenging in drier, underdeveloped and developing nations with large populations, because demand in those areas is high and supply is low. Whether people get enough depends greatly on where they live, because the distribution of global water resources varies widely. Malin Falkenmark of the Stockholm International Water Institute and other experts estimate that, on average, each person on the earth needs a minimum of 1,000 cubic meters (m 3) of water per year-equivalent to two fifths of the volume of an Olympic-size swimming pool-for drinking, hygiene and growing food for sustenance. Solving the world’s water problems requires, as a start, an understanding of how much freshwater each person requires, along with knowledge of the factors that impede supply and increase demand in different parts of the world. Governments and authorities at every level have to formulate and execute concrete plans for implementing the political, economic and technological measures that can ensure water security now and in the coming decades. Because lack of access to water can lead to starvation, disease, political instability and even armed conflict, failure to take action can have broad and grave consequences.įortunately, to a great extent, the technologies and policy tools required to conserve existing freshwater and to secure more of it are known I will discuss several that seem particularly effective. ![]() What is more, many water sources are threatened by faulty waste disposal, releases of industrial pollutants, fertilizer runoff and coastal influxes of saltwater into aquifers as groundwater is depleted. Scientists expect water scarcity to become more common in large part because the world’s population is rising and many people are getting richer (thus expanding demand) and because global climate change is exacerbating aridity and reducing supply in many regions. By midcentury as much as three quarters of the earth’s population could face scarcities of freshwater. By 2025, according to data released by the United Nations, the freshwater resources of more than half the countries across the globe will undergo either stress-for example, when people increasingly demand more water than is available or safe for use-or outright shortages. That the problem is well-known makes it no less disturbing: today one out of six people, more than a billion, suffer inadequate access to safe freshwater. Wise use of such power will become increasingly important as the years go by because the world’s demand for freshwater is currently overtaking its ready supply in many places, and this situation shows no sign of abating. Politicians there have allowed irrigation water to be shifted away from farming operations to cities and suburbs, while permitting recycled wastewater to be employed for landscaping and other nonpotable applications.Īs in New Delhi and Phoenix, policymakers worldwide wield great power over how water resources are managed. Although Phoenix sits amid the Sonoran Desert, he enjoys a virtually unlimited water supply. My son, who lives in arid Phoenix, arises to the low, schussing sounds of sprinklers watering verdant suburban lawns and golf courses. New Delhi’s endemic shortfalls occur largely because water managers decided some years back to divert large amounts from upstream rivers and reservoirs to irrigate crops. ![]() ![]() He rushes to fill the bathtub and other receptacles to last the day. Although the area gets a fair amount of rain every year, he wakes in the morning to the blare of a megaphone announcing that freshwater will be available only for the next hour. A friend of mine lives in a middle-class neighborhood of New Delhi, one of the richest cities in India.
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