Mapping of Chlorophyll-A in the Dubai Creek Area Using WorldView-2 Imagery and Field Data
Occurrences of harmful algal blooms (HAB) in coastal regions have been increasing both in frequency and magnitude in the last few decades. The coasts of United Arab Emirates UAE have been affected by massive HABs in 2008 and 2009 that lasted for months and encouraged frequent monitoring of algae and nutrient concentrations in the area. Other small scale algal blooms were also observed in recent years as well. The increasing anthropogenic activities in the Dubai area have led to increased growth of algae in the Dubai Creek. This paper presents the results of a study aimed at mapping of chlorophyll-a, which is a direct indicator of algal growth in the creek. A spectral model of chlorophyll-a was developed from WorldView-2 data of the creek that was acquired in July, 2012. Field data of chlorophyll-a collected at the time when the WorldView-2 image was acquired, have been used for calibration and verification of the spectral model, which showed an 82.7% correlation with field data. Development of such a model is useful for spatiotemporal mapping of algae in the area. Such information is essential for monitoring of the levels of pollution in the Emirate of Dubai coastal area and for planning and decision making activities related to the sustainability of the creek.