miércoles, 9 de septiembre de 2015

Sed


Uno se sorprende al leer la lista de países que figuran en el cuadro de arriba: no menos de 25 de los 33 países que se mencionan pertenecen al Medio Oriente ampliado y norte de Africa (o sea, a esa franja geoestratégica conocida por el acrónimo inglés de MENA: Middle East & North Africa). Sorprende no ver en el club de los sedientos a países del este y Cuerno de Africa como Sudán, Etiopía, Eritrea, Somalía. En síntesis: uno ya intuye cuáles van a ser las regiones de conflictos calientes, más avanzado el siglo que transitamos. Completan la lista Chile (único país de América), cuatro europeos (San Marino, Macedonia, Grecia y España) y Singapur en Asia. Lo que sigue fue escrito por Esha Dey para el sitio web Vice News (https://news.vice.com/article/the-world-is-running-out-of-water). Acá va:


Título: These Nations Are About to Start Running Out of Water

Texto: About one-fifth of all countries in the world will face acute water shortage by 2040 as climate change disrupts rainfall patterns and a growing population pushes up demand, according to an analysis by the non-profit research organization World Resources Institute (WRI).

The study ranked all countries according to the severity of the water crisis they are estimated to face, and the Middle East stood out as the most vulnerable region. Fourteen of the 33 countries most likely to suffer water shortfalls are in the region, including nine that are considered extremely susceptible: Bahrain, Kuwait, Palestine, Qatar, the United Arab Emirates, Israel, Saudi Arabia, Oman, and Lebanon.

"The region, already arguably the least water-secure in the world, draws heavily upon groundwater and desalinated seawater, and faces exceptional water-related challenges for the foreseeable future," says the report.

Other nations that are likely to experience shortages include the big economies of the United States, China, and India. These countries are already struggling with water scarcity and will continue face similar levels of water crisis through 2040. However, some regions, including the Southwestern United States and China's Ningxia Province, may see a 40 to 70 percent intensification of their water deficits.

Australia, Indonesia, the Philippines, Mongolia, Namibia, South Africa, Botswana, Peru, Chile, and several North African countries are also at high risk for severe water scarcity by 2040.

For the study, the researchers divided the world into several smaller regions and matched projected rainfall patterns for each region with the expected growth in water demand. A country whose need for water was estimated to be more than 80 percent of its available surface water, was classified to be at "extremely high" risk of water scarcity.

Charles Iceland, a director with WRI's Food, Forests, and Water Programs, said the rainfall projections used in the study were derived from climate models that predict how such patterns would change if global warming continues unabated. Nations closest to the equator, he said, are projected to be hit hardest.

"Climate models tend to agree that in a warmer climate the water that is evaporating off the Equator is going to go higher up in the atmosphere and will travel further north and further south," Iceland said. "So the places that get rains now, are going to be passed by as the water column is going to go further south and north."

In addition to those changing precipitation patterns, water demand projections were calculated based on population growth projections and the pace of economic development.

"With greater economic growth, countries are using more water per capita," Iceland said. He added that the world population is well on its way to reach the 9 billion mark by 2050.

While climate change and population growth are the dominant factors, the dynamics that put pressure on water resources differ from region to region. For example, WRI projects Chile to transition from a moderate level of water scarcity in 2010 to an extremely high level in 2040 due to the combination of rising temperatures and shifting rain patterns. Botswana and Namibia, however, are already facing water challenges, which will be seriously worsened due to climate change.

"The fundamental human right of access to clean water is a huge challenge, even now, in the current climate," Noah Diffenbaugh, a professor at Stanford University's School of Earth, Energy and Environmental Sciences, told VICE News. He too believes that the water crisis will unfold differently from country to country and will require unique, customized solutions.

As much as climate change is stressing water supplies, agriculture - which uses up 70 to 90 percent of a country's rainwater - is in need of a complete overhaul, experts said. More efficient technologies, drought resistant crops, among other techniques could alleviate the stress.

The outcome of heightened water scarcity could be chaos and conflict, particularly in already crisis-prone regions, like the Middle East and Africa, according to many recent studies, including one from the US Department of Defense.

The WRI report highlighted the complex fashion in which such threats are manifested.

"What stood out for me in this report was that a number of countries where we already see a high degree of geopolitical tension were the same countries that ranked very high in the future water stress ranking," Iceland said.


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Como lectura complementaria al artículo anterior, este mismo sitio ofrece la siguiente nota de Laura Dattaro:


Titulo: The World Is Running Out of Water

Texto: Humans are depleting underground aquifers around the world at alarming rates, threatening hundreds of millions of people who rely on them for survival, according to a comprehensive study conducted by researchers from NASA and the University of California, Irvine.

Twenty-one of the world's 37 largest aquifers are losing water at a greater rate than they're being refilled, falling victim to population growth and climate change. Thirteen of those diminishing water sources are experiencing "significant distress," including the Arabian Aquifer System, which supplies Saudi Arabia, Syria, Iraq, and Yemen, the Murzuk-Djado Basin in northern Africa, the Indus Basin of India and Pakistan, and the Central Valley Aquifer System in California.

"It's very serious," Jay Famiglietti of NASA's Jet Propulsion Laboratory and an author of the report told VICE News. "All over the world, we use more water than we have available to us on a renewable basis."

The scientists analyzed 10 years of data from NASA's GRACE satellites, which measure anomalies in the Earth's gravity brought about by changes in water supplies.

More than two billion people around the world rely on aquifers as their sole source of drinking water, according to UNESCO. Losing that water can disrupt economies and drive conflicts, particularly in areas of the world that are already unstable, said Charles Iceland of the World Resources Institute.

Syria, for example, experienced its worst drought on history in the years prior to the outbreak of civil war in 2011. Desperate farmers turned to groundwater supplies, which diminished, forcing some of them to flee their homes. An estimated one million rural Syrians relocated to the country's cities. A wide range of researchers and government officials say this massive social dislocation helped feed anti-government sentiment.

Yemen, where water supplies in some urban areas could run dry by the end of the decade, could soon see a similar situation, Iceland said.

"People see the decline in these groundwater levels and they're worried, if they run out of water, populations will have to migrate somewhere else," Iceland told VICE News. "As if there isn't enough problem with state dissolution there, Yemen could fall into even greater chaos."

A 2012 State Department report found that water shortages are likely to contribute to instability in areas crucial to US national security over the next 10 years. Water supply shortages, the department's National Intelligence Council warned, could lead to state collapse, inflame regional tensions, and distract US diplomatic partners from cooperation on shared policy goals.

But while it's clear groundwater is disappearing in many places, no one knows exactly how much water remains in the world's aquifers, making it impossible to know when they might run dry, Famiglietti said. Many are deep underground and in difficult to reach places. So unlike oil and natural gas reserves, accurate estimates of the world's water supply are elusive. For example, projections for when the Northwest Sahara Aquifer System might be entirely depleted range from 10 years to 21,000 years.

In the meantime, dipping ever further into our groundwater sources is wreaking havoc below ground — as well as above.


"There's serious ecological damage being done right now. The ground is sinking in California, streams are being depleted, the water table is falling, wells are running dry, the quality of water is degrading," Famiglietti told VICE News. "We really are past these sustainability tipping points, so it sure as heck would be good to know how much water is left. We're depleting it very quickly."


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