Collection 6.1

After the successful implementation of MODIS Collection 6, work began to find improvements for the next iteration of calibrated data products. Collection 6.1 marks an incremental improvement over Collection 6.
For Terra MODIS data products, in response to science user feedback and in coordination with the MODIS science team, MCST developed and implemented a correction to cross-talk effects observed in the PVLWIR bands (27-30). The correction is based on lunar observations and reduces the impact of cross-talk on L1B data as well as higher level data products.
Terra Collection 6.1 also includes reprocessed results for band 10. Midway through production of Collection 6, MCST implemented a change to improve the gain calculation for band 10 by incorporating Earth-view data, similar to the method used in bands 1-4, 8, and 9. This change was announced in 2014 and implemented over the course of several months of that year. The Collection 6.1 data products incorporate this change for all of band 10 data, including early mission data to allow for a complete data record. Band 1 and 2 data was also reprocessed from the start of 2012 to reduce the impact of forward predictions to the calculated gain. Forward processed results start on 2017/057 for these bands.

Aqua Collection 6.1 is primarily a continuation of the algorithm used in Collection 6, with only the addition of Earth-view data incorporated in the gain calculation of bands 1-4 and 10. The same approach was introduced in Terra Collection 6 and is similarly applied in Collection 6.1 for Aqua data. Data for these bands was reprocessed, using this updated algorithm to mission-start to produce a complete data set.

Collection 6.1 does not include a full-mission reprocess of all MODIS data products, only the bands addressed with changes differ from currently produced Collection 6 results. Higher-order data products that use tests based on a combination of bands (such as the cloud mask) may see an impact.

Caption: Band 27 image comparison of Hurricane Fabio of the coast of Baja, California on July 3, 2018 for Collection 6 (left) and Collection 6.1 (right).  In Collection 6, crosstalk contamination introduces striping, false land/water boundary features near the top of the image, and a temperature inversion of the clouds relative to the water.  In Collection 6.1, the striping is greatly reduced, the land/water boundary features are removed, and the temperature inversion is corrected.

References:
Wilson, T., A. Wu, A. Shrestha, X. Geng, Z. Wang, C. Moeller, R. Frey, and X. Xiong, "Devlopment and Implementation of an Electronic Crosstalk Correction for Bands 27–30 in Terra MODIS Collection 6", Remote Sensing, vol. 9(6), issue 569, 2017.