The Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP) spacecraft has been on orbit for more than five years. Pronounced striping in Earth view (EV) images and obvious discontinuity in the EV brightness temperature (BT) of the thermal emissive bands (TEB) during the blackbody (BB) warm-up cool-down (WUCD) calibration have been found since launch but the root-cause of the phenomena has not yet been identified. Meanwhile, recent studies of the MODerate-resolution Imaging Spectroradiometer (MODIS) long-wave infrared (LWIR) photovoltaic (PV) bands demonstrate that crosstalk effect induces the same erroneous features. In this paper, it is shown that there is, indeed, a remarkable crosstalk contamination in SNPP VIIRS TEB. The crosstalk effect is quantitatively characterized by deriving the crosstalk coefficients from the scheduled lunar observations and the established lunar imagery analysis. Among all SNPP VIIRS TEB, band M14 is shown to have the largest crosstalk contamination from Band M15, while bands M13, M15, M16, and I5 have pronounced crosstalk effect as well. The crosstalk effect is distinctively different for the odd and even detectors within each affected band during to the pattern of the placement of the odd and the even detectors of the band on the focal plane assembly (FPA). The crosstalk coefficients are applied to mitigate the crosstalk effect and the improvements to both the BB calibration and EV retrieval are presented and addressed.
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