Sentinel 2A: Geometric accuracy off by nearly 50 m

Hi there,

I downloaded the following scene from scihub
S2A_OPER_PRD_MSIL1C_PDMC_20160817T180350_R008_V20160816T104022_20160816T104025

I used sen2cor for correcting the atmospheric effects for one granule (T34WBD), located in northern Fennoscandia. I then created a raster stack in R using the raster package, and exported the multiband raster to GIS software. At this point I noticed that the product has a shift of almost 50 m southward, when compared to lake-polygons, which should be geometrically accurate. The shift seems to be systematic throughout the scene. To ensure that the lake poloygons were in place, and that I haven’t messed up with coordinate systems and transformations, I compared the polygons to Landsat 8 imagery, and the lakes did align perfectly there. Here is an image about the shift:

Am I doing something wrong here, as the accuracy is much worse than I expected *.

@reimari

Hello,

The product you have flagged (from S2A Absolute orbit 6011 of the 16th of August, 2016) is identified as having a Geolocation Error in ‘Table 3-2: Anomalies not related to processing’ in the Data Quality Report.

The issue arose as a consequence of a unnanounced Collision Avoidance Manœuvre. Geolocation in affected products (Orbits 6003 - 6011)is in the region of 45 - 120 metres.

Cheers

Jan

S2 MPC Operations Manager.

Hi Jan,

Thank for the quick reply, and for pointing that out. I didn’t notice that, but it now makes sense!

-R

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