Thermal anomaly across the Israel-Egypt political border was observed in satellite images. This anomaly was explained by the different properties of the sand dunes of both sides of the border. While the Israeli side is covered by biogenic soil crust, the Egyptian side is characterized by bare sands.
The biogenic soil crust consists mainly of cyanobacteria and particles of silt and clay and therefore is much darker than the dune sands. Consequently, the crust’s temperature was found to be considerably higher (up to 4°C) than the substrate bare sands.
Algorithms for retrieving land surface temperature from different satellites were developed, and the crusts’ thermal property was linked to the surface energy balance.
Qin, Z., Pedro Berliner, P., and Karnieli, A. 2005. Ground temperature measurement and emissivity determination to understand the thermal anomaly and its significance on the development of an arid environmental ecosystem in the sand dunes across the Israel-Egypt border. Journal of Arid Environments, 60, 27-52.