I’m not sure if the forum is a good place to discuss it, but I recognized that a lot of Sentinel-2 products, which were classified with a cloudcoverpercentage of 0 contain clouds. Thus, my question is if it makes sense to report those products to the esa or somewhere else or just ignore it?
Okay, that sounds good. But actually I’m not sure if it is only a bug or if it is just too difficult at the moment to detect every cloud over the sea ice.
For computing the cloud percentage in the metadata, they are used the cloud masks that you can find in the L1C product (cirrus clouds + opaque clouds), so if the clouds are identified in the masks but not in the cloud percentage in the metadata, then it is the known bug. If the clouds are not identified in the masks, then it is the algorithm who cannot detect them.
On the other hand, I have just heard that in the new version (which will be in operation soon) the algorithm used for generating the cloud masks has been improved.