How to solve greenhouse effect? Build greenhouses

EL EJIDO, Spain Thu Oct 9, 2008 12:39pm EDT

1 of 2. A worker puts a plastic sheet over the top of a greenhouse under-construction in El Ejido, southern Spain, in this March 7, 2007 file photo.

Credit: Reuters/Francisco Bonilla

EL EJIDO, Spain (Reuters Life!) - The greenhouse effect may be heating the planet but a new study says Europe's driest spot, Almeria, Spain, is actually cooling ... thanks to greenhouses.

A group of researchers at the University of Almeria found that the southern Spanish province had so many commercial greenhouses, seen from space as a white swathe across the arid province, that they reflected solar energy back into space.

Seventy percent of the province's coastal strip -- 30,000 hectares (74,130 acres) -- is covered in transparent plastic sheeting used to grow thousands of tonnes of fruit and vegetables for export.

While global temperatures have risen 0.7 degrees Celsius in the last 100 years, and 1.3 degrees in Spain, the western half of the province has cooled 0.3 degrees every decade for the last 25 years, reported the study, published in the Journal of Geophysical Research.

"This fall is equivalent, in almost three decades, to 0.9 degrees, practically equivalent to the rise in the rest of the world. We have bought ourselves almost a century of time," said Pablo Campra, who led the study.

The province on Spain's south-eastern corner bakes under 330 days of sunshine a year and is so desert-like film-makers in the 1960s used it to shoot "Spaghetti Westerns" like 'The Good, the Bad and the Ugly' starring Clint Eastwood.

Campra added that so much produce was grown there the greenhouses acted as a 'carbon sink', absorbing 10 tonnes of carbon dioxide for every hectare (2.5 acres) cultivated.

"If right now you eliminated all the greenhouses and our theory is 100 percent correct, it could be catastrophic since temperatures in the area would shoot up," he said.

(Writing by Ben Harding, editing by Paul Casciato)