An evaluation of the temporal stability of HJ-1 CCD data using a desert calibration site and Landsat 7 ETM+

Abstract

Remote-sensing data from the China Huan Jing 1 charge-coupled device (HJ-1 CCD) sensors have been extensively used to capture the dynamics of the Earth’s resources and environment, and to complement Landsat observations. It is critical to obtain radiometrically continuous and consistent measurements from multiple instruments spanning various periods. This study evaluated the radiometric stability of the HJ-1 CCD sensors since launch based on the stable Dunhuang calibration site and the Landsat Enhanced Thematic Mapper Plus (ETM+). The top-of-atmosphere (TOA) reflectance trends revealed from all rigorous selected cloud-free images showed that all bands of the CCD sensors degraded with time ranging from 1% to 7% per year, with the near-infrared (NIR) bands exhibiting the greatest drift. In addition, comparisons between the simultaneous HJ-1 CCD and Landsat ETM+ data revealed that the HJ-1 CCD agreed with the ETM+ within 3% for blue, green, and red bands after adjustment for spectral differences, whereas the NIR bands exhibited larger uncertainties at the level of 4%. The results provided comprehensive analysis of the long-term radiometric performance of the HJ-1 CCD sensors, which will serve as a reference for further applications using HJ-1 CCD data, as well as for successor missions of Chinese satellites, e.g. the Gaofen (GF) series of Earth observation satellites.

Acknowledgements

The authors thank the China Centre for Resources Satellite Data and Application (CRESDA) for providing the HJ-1 CCD data set. We thank Brent. N. Holben for his effort in establishing and maintaining the Dunhuang AERONET (Aerosol Robotic Network) site. Special thanks are due to Prof Chuanmin Hu (University of South Florida) for his insights and encouragement of this work.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (Nos. 41331174, 40906092, 41406205 and 41461079), the national 863 key Project (2012AA12A304), the National Basic Research Programme (973 Programme) (No. 2011CB707106), the Major Science and Technology Program for Water Pollution Control and Treatment (2013ZX07105-005); the Programme for Changjiang Scholars and Innovative Research Team in University (IRT1278), the Hong Kong Research Grants Council (RGC) General Research Fund (GrantNo.B-Q23G), Special Fund by Surveying & Mapping and Geoinformation Research in the Public Interest (201412010); Special Fund by Mapping Technology Plan in 2014 ‘Using UAV images to Identify and Extract Disaster information’; the Open Research Fund of State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research (IWHR-SKL-201514); the Open Research Fund of Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences (No. 2013LDE004), LIESMARS Special Research Funding, the ‘985 Project’ of Wuhan University; Special funds of State Key Laboratory for equipment.