Sun, JQ; Guenther, B; Wang, MH (2019). Crosstalk Effect and Its Mitigation in Aqua MODIS Middle-Wave Infrared Bands. EARTH AND SPACE SCIENCE, 6(5), 698-715.
Abstract
The MODerate-resolution Imaging Spectroradiometer (MODIS) has 36 bands, among which 6, bands 20-25, are middle-wave infrared (MWIR) bands, covering a wavelength range from approximately 3.750 to 4.515 mu m. Significant crosstalk effect in Aqua MODIS MWIR bands was found prelaunch and confirmed on-orbit early in the mission. In this paper, the crosstalk effect in these bands is carefully investigated and quantitatively characterized using the instrument's scheduled lunar observations. The crosstalk correction algorithm that we have developed in our previous work is applied to all levels including black body calibration and L1B EV retrievals to mitigate the crosstalk effect in the bands. We show significant crosstalk contaminations among all MWIR bands and also show that these bands have significant crosstalk contaminations from the shortwave infrared bands. We demonstrate that the crosstalk effect has significant impact on onboard black body calibration as well as on EV retrievals. For L1B EV retrievals, these crosstalk effects induce significant radiometric bias as well as strong striping. The radiometric bias is larger than 1.8 K for all detectors of the 4.47-mu m band (band 24) for typical scene. Aqua MODIS band 24 detector 1 is most strongly impacted by crosstalk and has a bias that may be as large as 10 K. The crosstalk correction successfully mitigates the striping in the EV images and improves the accuracy of the EV retrievals in the MWIR bands.
DOI:
10.1029/2018EA000391
ISSN:
2333-5084