Strange low NDVI values with sen2cor 2.10.01

Good morning, since the end of January, when I calculate the NDVI from Sentinel 2 images, I get a value which is systematically about 0.1 points lower than the NDVI calculated from Landsat images and also than that calculated with the specific SNAP function.
I get this lower value both if I calculate the NDVI directly from Level 2 images and if I start from Level 1 images and apply sen2cor vers 2.10.01 to them.
Does the same happen to others of you? Can it be related to the new version of sen2cor?
Matteo De Sancts


Nobody is having the same problem?

Hello, i think this problem is related to the 1k offset added since 25th January to all S2 data.
I guess this offset is not added to Sen2Core, there should be a specific option to enable.
Check this Sentinel-2 MSI Level-1c Band 10 values


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Thank you Alessandro, it could be the reason of NDVI strange values…

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It is the reason! Thank you again Alessandro!

Dear user,

As indicated in point 4) of Sen2Cor FAQ, a radiometric offset has been introduced since PB04.00 that needs to be taken into account when converting L2A image Digital Numbers into L2A Surface reflectance.



Dear all,

I add the same problem of low NDVI values and I corrected the values (with a substraction of 1000) of the L2A bands red and nir output of sen2cor to get the good values of the indice.
However I am a bit disapointed with the SCL bands : since 25-01-2022, I only have 8 and 9 for this band (clouds with high or medium probability).
Are you aware of that ?
The shift of 1000 must be apply on the L1C bands before running sen2cor on it ?
Thanks for your answer.
Aline Déprez

Dear @deprezal,

Thank you for your message.

We provided an answer to the issue your are facing in post shift-of-1000-in-s2-reflectance-since-25-01-22

We hope you find the answer useful.