In this monthly feature, we span the globe to examine Our Changing Landscape with time series of medium resolution RapidEye satellite imagery. The RapidEye archive dates back to late 2008 and already contains more than 5 billion square kilometers of data. This month, we revisit a previous edition of Our Changing Landscape with a look at recent changes in the water level of the Dead Sea.
The RapidEye Constellation
RapidEye is a constellation of five 5-meter medium resolution satellites each offering five spectral bands of information. The RapidEye constellation offers daily revisits to every location on the planet with a huge footprint that is 77-km wide. The data is priced competitively with a starting cost of $1.28 per square kilometer for all five spectral bands – academics do receive discounts. RapidEye adds a fifth band, the red edge, to the ‘traditional’ multispectral set of blue, green, red and near-infrared (NIR). The additional spectral data in the red edge band allows users to extract more useful land ‘information’ than can be from traditional 4-band imagery sources. When RapidEye imagery is ordered as a Level 3A Orthorectified product, images from multiple dates are extremely well registered, making it the ideal data source for Our Changing Landscape.
An Update on the Dead Sea
In the June 2012 edition of Our Changing Landscape, we introduced the pending environmental disaster of the Dead Sea and its surrounding lands; and in this April 2015 edition, we continue the story with a look at changes in this body of water over the past three years. Unfortunately, the story has changed very little since our 2012 article as the water level in the Dead Sea continues to drop. 2015 estimates put the decline in water level at about 1.1 meters per year with the current level at about 425 meters, which is more than 40-meters lower than it was measured in the 1950s.
During December 2013, heavy rains fell on Israel but the water levels in the Dead Sea continued to decline despite increases in surrounding water bodies and aquifers. The drop in December 2013 was about 3-centimeters (cm) which is far less than in December 2012 (i.e. it was 11-cm). That said, it is a disturbing trend to see water levels continuing to drop despite heavy rains. This suggests much of the rain was absorbed by the parched surrounding lands, and that inflows from the Jordan River, the main source of water for the Dead Sea, continue to decline.
One possible ray of sunshine for the Dead Sea is the historic agreement recently reached between Israel and Jordan. In part, the agreement calls for the construction of a desalination plant by the Red Sea to provide clean drinking water to both Israel and Jordan. Further, Israel will sell more water to Jordan from the Sea of Galilee. Finally, the 100 million cubic meters of briny leftovers from the desalination plant will be piped some 180 kilometers to the Dead Sea. While this agreement is a start in slowing the declining Dead Sea water levels, it is not close to the estimated 800 million cubic meters of water that would be required to halt it all together.
If you would like to find out more about using RapidEye for your academic studies, engineering projects or any landscape analysis, let us know at [email protected] or (303) 993-3863.