Year-end Sale % OFF 
Abstract
This study presents preliminary results of the validation of the Moderate Resolution Imaging Spectroradiometer (MODIS) daily LST products (MOD/MYD11A1, Version 5) using longwave radiation ground measurements obtained at 12 stations in the North Arid and Semi-Arid Area Cooperative Experimental Observation Integrated Research program. In this evaluation process, the broadband emissivity at each station was obtained from the ASTER Spectral Library or estimated from the MODIS narrowband emissivity Collection 5. A comparison of the validation results based on those two methods shows that no significant differences occur in the short-term validation, and a sensitivity analysis of the broadband emissivity demonstrates that it has a limited effect on the evaluation results. In general, the results at the 12 stations indicate that the LST products have a lower accuracy in China’s arid and semi-arid areas than in other areas, with a mean absolute error of 2–3 K. Compared with the temporal mismatch, the spatial mismatch has a stronger effect on the validation results in this study, and the stations with homogeneous land cover have more comparable MODIS LST accuracies. Comparisons between the stations indicate that the spatial mismatch can increase the influence of the temporal mismatch.
Highlights
Land surface temperature (LST) is a key parameter in climatological and environmental studies [1,2].Obtaining LST data is important considering its common use in environmental studies and resource management
There are a few outliers positioned far from the y = x line that are mostly located below the y = x line; the Moderate Resolution Imaging Spectroradiometer (MODIS) LSTs that have large errors correspond to these underestimated data
One explanation for the outliers is that the cloud effect was not completely eliminated; as a result, the pixels in the MODIS land surface product images appear to represent a lower temperature than the ground-measured temperature
Summary
Land surface temperature (LST) is a key parameter in climatological and environmental studies [1,2]. Obtaining LST data is important considering its common use in environmental studies and resource management. Measuring LST from ground-based instruments at the regional and global scales is practically impossible; the use of satellites in the thermal infrared (TIR) region is a viable option [3]. Evaluating satellite LST retrievals is critical to their application, and the feedback from validation activities helps improve the generation of these products [4,5]. LSTs are very difficult to validate because of their large spatial and temporal variation, during the daytime. The careful selection of validation sites is essential [5,6,7]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
