Sea water salinity estimation over Dubai using satellite imagery & WASI empirical model approach. application to SpaceD DEWASAT-2 nanosatellite

The scarcity of water is increasingly posing a significant peril to numerous countries. Nations that previously did not face acute water shortages are now grappling with the challenge of securing sufficient freshwater sources. Industrial desalination facilities emerge as one of the most effective technological remedies for extracting fresh water from seawater. Areas such as the Gulf countries have addressed water scarcity issues by implementing thermal desalination plants powered by fossil fuels. Regarding the United Arab Emirates (UAE), there are two primary sources of freshwater production: underground water and desalinated seawater. In the case of underground water, the levels are not enough and only serve a little more than 1% of the nation’s needs. For the second source, nearly 99% of freshwater consumed in Dubai now is produced from its desalting units, which use thermal distillation as the dominant technology. The main seawater intake for the desalinization plants requires continuous monitoring and measuring of the seawater salinity at certain underwater depths and specific distances from the coast strip line. Moreover, continuous water salinity mapping and monitoring are critical to environmental sustainability. Poor seawater quality has an impact not just on aquatic life but also on the ecosystem. This paper proposes an optical satellite imagery analytical solution incorporating a Water Color Simulator (WASI) approach to estimate and map Dubai’s seawater salinity using a DEWA nanosatellite. In the first phase, the estimation and analytics have been developed using the Landsat imagery series, I.T. infrastructure, and imagery analytics platform as part of the SpaceD DEWA project. The findings indicate a robust and positive relationship between the reflectance values detected by the satellite and the on-site measurements obtained from three coastal stations near the primary desalination facility owned by DEWA, R2 equal to 0.704. In a second phase, this system will be used with the imagery of DEWASAT-2, a new nanosatellite launched by DEWA in April 2023. The main characteristics of the nanosatellite and the imager payload are introduced in this paper.