MODIS NRT Land processing transitions from C6 to C61 - Update

Updated: 2021-02-23 -- Please note that the planned transition of the NASA LANCE Near Real-Time (NRT) MODIS Land processing to the new Collection 61 (C61), from nrt3, has been now pushed back to April 1, 2021. Till this time the current Collection 6 (C6) will continue to be made available from nrt3. During this transition period, users are encouraged to start evaluating the C61 land products that is being made available from nrt4, to aid in the transition of their applications to this new collection data. After the transition on April 1, 2021, the C6 will be fully discontinued from both nrt3/4 and C61 will become available from nrt3/4. (Read details below).

Updated: 2021-02-09 -- The MODIS NRT Land processing transition to the new Collection version C61 from the current collection version 6 (C6) has been delayed till February 22, 2021.

The NASA LANCE Near Real-Time Processing System plans to transition the MODIS Land processing to the new Collection version C61 starting February 22, 2021 from the current collection version 6 (C6). To help users transition their applications to the new collection data, the MODIS NRT processing system will run the two collection versions (C6 and C61) at NRT starting Jan 20, 2021. During this transition period (1/20/2021 - 2/22/2021) nrt4 will be configured to process and distribute C61 land data while nrt3 will continue to process and deliver C6 land products.

NOTE: The MAIAC (MCD19*) suite of products will continue from C6 for now, as we are still waiting for the final C61 specific changes for this process.

C61 mainly addresses some known issues and inconsistencies in the C6 L1B products, revealed by the MODIS Calibration Science Team (MCST), after the completion of the C6 reprocessing and hence most C61 land NRT products are largely identical to C6 equivalents, barring small changes introduced by the changes in L1B. The only other notable change in C61 has been a correction to flagging of some high-aerosol areas, in the L2 Land Surface-Reflectance (LSR) that is mostly seen over brighter desert areas. For further details on the C61 L1B changes and minor updates to other land products, users are requested to refer to this C61 Land change document. Additional details regarding the revision to the C61 L2 LSR high-aerosol flagging can be found here.

Users are requested to make a note of this proposed change in LANCE NRT MODIS products. For performance comparison of the C61 NRT and STD products, users can still refer to the C6 performance metrics that can be found here.

If you have any further concern or question about this transition please email the LANCE MODIS user support and for questions or information related to change in product quality contact land QA team.