Exploring the Potential of Thermal Remote Sensing for Marine Freshwater Springs Identification in the Arabian Gulf

The initial objective of this research is to understand if thermal remote sensing is a viable source to detect or identify submarine freshwater in the United Arab Emirates (UAE). It was established that the discharged freshwater was at least 0.5?C cooler than the surrounding seawater but the influence of the surrounding temperatures depends upon the time of year of observations. These findings are dependent upon the discharge volume of freshwater. Analysis of imagery acquired over the UAE began with two study areas: the first from Dubai to the Musandam peninsula, and the second from Abu Dhabi city north to Sir Abu Nu?Ayr. These two areas have been investigated using a time series of Landsat 8 thermal satellites to identify consistently appearing thermal anomalies on the sea surface. A trial area was chosen for ground truthing to validate the results using drop-down video and probe measurements. Several points were selected around each anomaly due to the large 100-meter pixel size of the thermal band. It is recommended to conduct the ground truthing focusing on anomalies in winter, which is a period of higher water table than in May. However, while submarine freshwater springs were not identified, there does appear to be some correlation with observations made from the remote sensing and features identified in the field. Therefore, the anomalies detected from the Landsat 8 imagery should not be discounted since it is highly probable that at least one of them may be identified because of groundwater discharge.