Drilling for Water Greens the Saudi Deserts
NASA’s Earth Observatory maps the changes and activities observed from up high including the changes to the desert landscape of Saudi Arabia.
Even before the British Geological Survey and University College London (UCL) declared its findings of large grounwater reserves under the soil of Africa, Saudi Arabia has been driling for water through layers of rock sediment for over 30 years! Some of the drills go down as much as a kilometer (65 miles)!
NASA and the U.S. Geological Survey has been mapping the green outcrops to the yellow landscape since 1987, 1991, 2000, and 2012 through Landsat satellites like the Wadi As-Sirhan Basin. One kilomter across, these agricultural initiatives have been using a regionally climatic appropriate irrigation technique – central pivot irrigation. The literal meaning of central pivot irrigation is applied to ensure distribution of water using segmented pipes tjat provide overhead sprinkling that move in a circular pattern. This method is most appropriate on flat land, and reduces water loss through evaporation.The water comes from underground aquifiers channeling water that dates back to the last Ice Age!
This is where some of the revenue from Saudi oil has gone to, and the last 26 years have born witness to wheat, fruits and vegetables, tripling desert agriculture from approximately 6.8 cubic kilometers in 1980 to about 21 cubic kilometers in 2006.
The only problem is with the low rainfall in the region, the groundwater present is a non-renewable natural resource, which might compromise the integrity of the desert in the long run, yet the polar shift might have other ideas!
“Crop Circles in the Desert: Image of the Day”. http://earthobservatory.nasa.gov/IOTD/view.php?id=77900&src=eoa-iotd