Publications

Chang, TJ; Xiong, XX; Keller, GR; Wu, XQ (2018). GEO-LEO reflective band intercomparison with bidirectional reflectance distribution function and atmospheric scattering corrections. JOURNAL OF APPLIED REMOTE SENSING, 12, 14002.

Abstract
The intercomparison of the reflective solar bands (RSB) between the instruments onboard a geostationary orbit satellite and a low Earth orbit satellite is very helpful in assessing their calibration consistency. Himawari-8 was launched on October 7, 2014, and Geostationary Operational Environmental Satellite (GOES)-R was launched on November 19, 2016. Unlike previous GOES instruments, the Advanced Himawari Imager (AHI) on Himawari-8 and the Advanced Baseline Imager (ABI) on GOES-R have onboard calibrators for the RSB. Independent assessment of calibration is nonetheless important to enhance their product quality. MODIS and visible infrared imager radiometer suite (VIIRS) can provide good references for sensor calibration. The intercomparison between AHI and VIIRS is performed over a pseudoinvariant target. The use of stable and uniform calibration sites provides comparison with accurate adjustment for band spectral difference, reduction of impact from pixel mismatching, and consistency of BRDF and atmospheric correction. The site used is the Strzelecki Desert in Australia. Due to the difference in solar and view angles, two corrections must be applied to compare the measurements. The first is the atmospheric scattering correction applied to the top of atmosphere reflectance measurements. The second correction is applied to correct the BRDF effect. The atmospheric correction is performed using a vector version of the Second Simulation of a Satellite Signal in the Solar Spectrum (6SV) model and the BRDF correction is performed using a semiempirical model. Our results show that AHI band 1 (0.47 mu m) has a good agreement with VIIRS band M3 within 0.15%. AHI band 5 (1.61 mu m) shows the largest difference (5.09%) with VIIRS band M10, whereas AHI band 5 shows the least difference (1.87%) in comparison with VIIRS band I3. The methods developed in this work can also be directly applied to assess GOES-16/ABI calibration consistency, a topic we will address in the future. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)

DOI:
10.1117/1.JRS.12.014002

ISSN:
1931-3195