| Author | Babu, Annabathula Sai Durga Shyam |
| Call Number | AIT RSPR no.RS-22-02 |
| Subject(s) | Water temperature--Remote sensing
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| Note | A research submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Remote Sensing and Geographic Information Systems |
| Publisher | Asian Institute of Technology |
| Abstract | Water is an important natural resource. Emissivity is one of its parameters that affect its emitted energy and hence its superficial temperature. The average water emissivity across a very large broadband range (1-100 m) is 0.96 for water temperatures ranging from 0 to 30 degrees Celsius. This research aims at performing sensitivity analysis and assesses the change of water surface emissivity and its impact on satellite-derived water temperature. This study applies and compares the sensitivity results over two water body systems: freshwater lakes of Sardinia Island (Italy) and two interconnected lagoons in Thua Thien Hue province (Vietnam). For both study areas, a simplified plank’s law is used to retrieve the water surface temperature (WST) data by modifying the emissivity parameter for the thermal bands of Landsat ETM+ and OLI datasets. Regression analysis is performed between the satellite retrieved and observed field WST. This study compared different satellite-derived WST accuracy statistical indicators such as R-squared, RMSE, NSE, and Pbias to determine the optimal value of emissivity. From the emissivity sensitivity analysis, this study demonstrated that the variation of emissivity in the simplified plank’s law does not significantly change the final estimated values of surface temperature. This means the simplified plank's approach is not sensitive to the variation of emissivity, even if they are relatively large. Even though the low variability of estimated temperature, the comparison of different accuracy indicators allowed the selection of the optimal emissivity values of 0.94 to be applied to both study areas. |
| Year | 2022 |
| Type | Research Study Project Report (RSPR) |
| School | School of Engineering and Technology |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Remote Sensing and Geographic Information Systems (RS) |
| Chairperson(s) | Virdis, Salvatore G.P. |
| Examination Committee(s) | Tripathi, Nitin K.;Sarawut Ninsawat |
| Scholarship Donor(s) | AIT Fellowship |
| Degree | Research Studies Project Report (M.Eng.) - Asian Institute of Technology, 2022 |