Minimize SYN Level 2 Product

The Level-2 SYN product, SY_2_SYN, is outputted by the SYNERGY Level-2 processor and contains:

  1. Level-2 surface reflectance (including error estimates) for the sun-reflective SLSTR channels (S1 to S6 for both nadir and oblique view) and for all OLCI channels, except for the oxygen absorption bands Oa14 and Oa15, and the water vapour band Oa20 (see the table below).
  2. Level-2 aerosol optical thickness at 550 nm (including error estimates).
  3. Level-2 Angstrom coefficient.
  4. Level-2 aerosol model index number (considered to be an annotation data file).

 

SYN CHANNEL SYN L1 CHANNEL INSTRUMENT CHANNEL CENTRAL WAVELENGTH (nm) WIDTH (nm)
1 B1 Oa1 400 15
2 B2 Oa2 412.5 10
3 B3 Oa3 442.5 10
4 B4 Oa4 490 10
5 B5 Oa5 510 10
6 B6 Oa6 560 10
7 B7 Oa7 620 10
8 B8 Oa8 665 10
9 B9 Oa9 673.75 7.5
10 B10 Oa10 681.25 7.5
11 B11 Oa11 708.75 10
12 B12 Oa12 753.75 7.5
13 B13 Oa13 761.25 2.5
14 B16 Oa16 778.75 15
15 B17 Oa17 865 20
16 B18 Oa18 885 10
17 B19 Oa19 900 10
18 B21 Oa21 1 020 40
19 B22 S1 (nadir view) 550 20
20 B23 S2 (nadir view) 665 20
21 B24 S3 (nadir view) 865 20
22 B25 S4 (nadir view) 1 375 15
23 B26 S5 (nadir view) 1 610 60
24 B27 S6 (nadir view) 2 250 50
25 B33 S1 (oblique view) 550 20
26 B34 S2 (oblique view) 665 20
27 B35 S3 (oblique view) 865 20
28 B36 S4 (oblique view) 1 375 15
29 B37 S5 (oblique view) 1 610 60
30 B38 S6 (oblique view) 2 250 50
List of SYN channels

All measurement datasets are provided on the OLCI Level-1B image grid consisting of the same number of columns and rows as the associated OLCI Level-1B product.

The SYN Level-2 SAFE product includes status flags, which are listed in the table below. In addition, the following datasets are propagated from Level-1B products:

  • flags
    • OLCI quality and classification flags
    • SLSTR exception summary and confidence flags
  • geolocation
    • DEM-corrected latitude
    • DEM-corrected longitude
    • DEM-corrected altitude
  • OLCI time stamps
  • OLCI sub-sampled annotation datasets
    • solar illumination zenith angle
    • solar illumination azimuth angle
    • viewing zenith angle
    • viewing azimuth angle
  • geophysical atmospheric datasets (ECMWF)
    • mean sea level pressure (hPa)
    • total column ozone (kg m-2)
    • total column water vapour (g cm-2)
  • The same measurement and annotation data are provided for pixels considered as removed in the OLCI Level-1B product

 

FLAG MASK FLAG MEANING DESCRIPTION
20 cloud Identifies clouds.
21 snow_risk Foreseen for indicating areas with or without snow/ice that are not clouds, but present features similar to clouds.
22 shadow_risk Foreseen for indicating cloud shadows.
23 cloud_filled Foreseen for indicating where cloud borders and holes were filled.
25 land Identifies land.
28 partly_cloudy Averaging region contains cloudy pixels.
29 partly_water Averaging region contains water pixels.
210 border Averaging region contains fewer pixels, because pixel is at the boundary of the camera image.
211 aerosol_filled Aerosol optical thickness was filled.
212 success Aerosol retrieval was successful.
213 negative_curvature Aerosol retrieval failed because of negative error metric curvature.
214 low Aerosol retrieval failed because retrieved value too low.
215 high_error Aerosol retrieval failed because relative error was too high.
SYN Level-2 classification and aerosol flags