A critical factor in Locust control is areas which have recently transitioned from desert to vegetation. Greenness is the number of dekads (approximately ten days) passed since vegetation onset. Thus greenness is a measure which highlights this critical transition.
The warmer colours (dekads 1-3) indicate annual vegetation that has just recently become green, and this is preferred by Desert Locust. Darker colours (dekads 7 and beyond) are most likely areas of perennial vegetation (oasis, forests, etc.) that are not particularly favourable for Desert Locust.
The methodology allows a robust and reliable discrimination between vegetation and no vegetation. It identiļ¬es efficiently the vegetation close to the onset and avoids the classic commission errors (i.e., detecting vegetation when there is no vegetation on the ground), encountered with the NDVI-based approach in these arid and semi-arid areas.
Pekel, JF., Ceccato, P., Vancutsem, C., Cressman, K., Vanbogaert, E., Defourny, P. (2011). Development and Application of Multi-Temporal Colorimetric Transformation to Monitor Vegetation in the Desert Locust Habitat. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 4:(2), 318-326
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