Showing posts with label rainfall. Show all posts
Showing posts with label rainfall. Show all posts

Monday, May 26, 2014

Mega dry spell Spain's worst in 150 years

Parts of Spain are currently suffering through their most intense dry spell in a century and a half with Valencia and Alicante among the worst affected regions. Future predictions are not too rosy either, meteorologists warn.

The last eight months have been brutally dry for large swathes of southern and eastern Spain.

While huge storms buffeted Spain's Atlantic coasts and the Canary Islands during the winter and spring, Valencia and Alicante, as well as areas including Murcia, parts of Albacete province, and the Andalusian provinces of Jaén, Almería, Cadíz and Málaga have all been starved of rain.

In the last 150 years, there has never been "such a long and intense drought", according to the country's meteorological agency Aemet.

Indeed there are parts of the country where during "the second worst period of drought on record there was twice as much rain as now", meteorologist José Antonio Maldonado told Spanish free daily 20 minutos.

Rainfall levels in many areas have been less than half of those seen from 1971 to 2000, while some places have seen less than 25 percent of those levels.

Most dams are still at somewhere between 74 percent and 90 percent of capacity thanks to rains from earlier years, but some farmers are already struggling to water their crops, or have gone out of business.

Spain is also facing an uncertain water future: a 2013 study by the Spanish National Research Council (CSIC) looking at the period from 1945 to 2005 found the country's droughts were becoming more intense and more regular. More

     

     

    Wednesday, April 16, 2014

    The Future Is Evaporating: Climate Change Could Dry Out 30 Percent of the Earth

    Scientists expect the changing climate to bring on more drought; there's going to be less rainfall in the already arid regions.

    That alone would be bad news for denizens of the planet's dry zones—in some places in North Africa, the American Southwest, India, and the Middle East, water shortages could well become an existential threat to societies built there. But new research shows that in addition to less rain, the rate of evaporation is likely to rise, too. Combined, the two forces could dry out up to a third of the planet.

    The study, published in the journal Climate Dynamics last month, estimates that climate change will cause reduced rainfall alone to dry out 12 percent of the Earth's land by 2100. But if evaporation is factored in, the study's authors say that it will "increase the percentage of global land area projected to experience at least moderate drying by the end of the 21st century from 12 to 30 percent."

    “We know from basic physics that warmer temperatures will help to dry things out,” the study’s lead author, Benjamin Cook, a climate scientist with Columbia University and NASA's Goddard Institute for Space Studies, said in a statement. “Even if precipitation changes in the future are uncertain, there are good reasons to be concerned about water resources.”

    Writing in a 2011 literature review in the science journal Nature, the physicist Joe Romm elaborates on how increased heat and evaporation can lead to a vicious cycle: "Precipitation patterns are expected to shift, expanding the dry subtropics. What precipitation there is will probably come in extreme deluges, resulting in runoff rather than drought alleviation. Warming causes greater evaporation and, once the ground is dry, the Sun’s energy goes into baking the soil, leading to a further increase in air temperature."

    Disappearing soil moisture is likely to be a greater problem than previously thought, and the occasional downpour won't sate year-round crops. As Columbia University notes, "An increase in evaporative drying means that even regions expected to get more rain, including important wheat, corn, and rice belts in the western United States and southeastern China, will be at risk of drought."

    If it becomes too dry to cultivate crops on one-third of the planet's surface, there's little doubt that crisis will follow. For millions of people who depend on food grown in vulnerable regions, the future is literally evaporating. More