Evaluating Certain Approaches for Computing Land Surface Temperature Over Alluvial Plains of Northern India

Dual thermal bands capability of Landsat 8 allows for retrieving of land surface temperature (LST) which is essential in agricultural and environmental studies. Accuracy in LST retrieval depends upon capturing land surface emissivity (ε) with precision. Scientific community have different approaches to determine LST using ε as one of the essential inputs. This research evaluates Twumasi, SEBAL, and Stathopoulou approaches to determine LST over alluvial plain of Northern India. LST determined with the help of these approaches using Landsat 8 OLI/ TIR data from 8-12-2021 to 12-11-2023, were validated with the ground observations of air temperature recorded using Eddy covariance measurements, a highly sophisticated and precise techniques of turbulent flux measurements. It also presents an attempt to modify the Stathopoulou approach to estimate LST using single thermal band 10 instead of bands 10 and 11. Results revealed that Twumasi, and SEBAL approaches yielded better estimates of LST than Stathopoulou approach. Improved value of error statistics like mean error, mean bias error, mean absolute error, mean relative error, and root mean square error, and good values of Willmott index of agreement, Nash-Sutcliffe efficiency, and Pearson correlation coefficient were observed between observed air temperature and LST obtained using modified Stathopoulou approach. Hence, the use of modified Stathopoulou approach to compute LST is recommended to enhance the quality and capability of decision-making process.