Update on S3 SYN-VGT algorithm status PROBA-V QWG 4 24/11/2016

Transcription

1 ACRI-ST S3MPC Update on S3 SYN-VGT algorithm status PROBA-V QWG 4 24/11/2016

2 Agenda Continuity with PROBA-V data - Evolution of S3 SYN / Creation of an alternative Proba-V like processing chain Status of the S3 SYN & VGT-P real data 2

3 Continuity with Proba-V In the frame of S3 MPC : Ensure continuity with historical measurements (SPOT VGT and Proba-V) Fully compare the S3 SYN and Proba-V processing Technical Note S3MPC.ACR.MEM.021. i1r1 Comparison with PROBA-V algorithm DPM v1.6 28/03/2013 Evolution of S3 SYN or Creation of an alternative branch PROBA-V like» Mix between PROBA-V and S3 SYN algorithms» Production of several PROBA-V like products Need to confirm some choices before consolidated specification and implementation 3

4 Current S3 SYN processing 4

5 PROBA-V like processing chain - Activated through a specific switch - On request / Not operational 5

6 PROBA-V architecture NEW Product Step by step = Current Product 1. Comparison with SYN algorithm 2. Compliancy with SYN processing chain Choice between accuracy and consistency 6

7 Conversion in VGT TOA reflectances. PROBA-V S3 SYN Unprojected L1c TOA radiances in BLUE, RED, NIR and SWIR spectral bands Unprojected L1c TOA radiances in OLCI and SLSTR spectral band Conversion in TOA reflectances with d² Radiance 1. Conversion in surface reflectance a) using AOT computed during SYN L2 b) using climatological AOT E cos( s ) 2. Hyperspectral interpolation R surf_hyp 3. Hyperspectral upscaling R TOA_hyp 4. Hyperspectral filtering R TOA_VGT Difficult to adapt Two suggestions : Keeping SYN L2 algorithm climatological or computed SYN AOT Adapting SYN L2 algorithm 7

8 Conversion in VGT TOA reflectances. PROBA-V S3 SYN Unprojected L1c TOA radiances in BLUE, RED, NIR and SWIR spectral bands Unprojected L1c TOA radiances in OLCI and SLSTR spectral band Conversion in TOA reflectances with 1. Conversion in TOA reflectances with PROBA- V equation d² Radiance E cos( ) s R TOA_SYN 2. Hyperspectral interpolation R surf_hyp 3. Hyperspectral upscaling R TOA_hyp 4. Hyperspectral filtering R TOA_VGT Difficult to adapt Two suggestions : Keeping SYN L2 algorithm climatological or computed SYN AOT Adapting SYN L2 algorithm To be checked with SYN ESL 8

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10 Atmospheric Correction. PROBA-V S3 SYN SMAC algorithm Close to SMAC, with : O3 = 11 years TOMS climatology. TCWV = Meteo Belgium data interpolated values from ECMWF P surf = interpolated from DEM Aerosol content = AOT optimisation O3, TCWV and P surf = extracted from ECMWF Aerosol content = double optmisation 10

11 Atmospheric Correction. PROBA-V S3 SYN SMAC algorithm Close to SMAC, with : O3 = 11 years TOMS climatology. TCWV = Meteo Belgium data interpolated values from ECMWF O3, TCWV and P surf = extracted from ECMWF Same Auxiliary Files than PROBA-V P surf = interpolated from DEM Aerosol content = AOT optimisation Aerosol content = double optmisation Using ECMWF or same files than PROBA-V? 11

12 Atmospheric Correction. PROBA-V S3 SYN SMAC algorithm Close to SMAC, with : O3 = 11 years TOMS climatology. TCWV = Meteo Belgium data interpolated values from ECMWF O3, TCWV and P surf = extracted from ECMWF Same Auxiliary Files than PROBA-V P surf = interpolated from DEM Aerosol content = AOT optimisation Aerosol content = double optmisation AOT optimisation Using ECMWF or same files than PROBA-V? Using AOT optimisation or S3 SYN optimisation? 12

13 PROBA-V architecture Remapping = same filter Directly linked to the acquisition grid Simple projection on the 1km Plate-Carrée grid using Main deviation from S3 SYN processing chain 13

14 PROBA-V architecture Not Applicable Currently same as VGT New Cloud detection planned Alignment to be re-discussed after consolidation of SYN cloud masking 14

15 PROBA-V architecture To be included in the S3 SYN VGT S processor Currently same compositing method applied (MVC) Updates: Specific selection rules (spectral bands, radiometric quality, clear pixel, SZA) Computation of status map S / / 21-end of month 15

16 Several possibilities triggered by switches Closest to PROBA-V algorithm 16

17 Several possibilities triggered by switches Closest to S3 SYN algorithm Alternative processing branch OR Evolution of S3 SYN 17

18 S3 VGT S software Only one product gathering : TOA reflectance TOC reflectance NIR from TOA and TOC Same content than the PROBA-V product L3 S1 TOC / L3 S10 TOC already produced (status map, selection of days, ) 18

19 Status of the S3 SYN & VGT-P real data 19

20 S3 SYN Status 1. Commissioning L1c not yet ended Planned early December Issue with geometric calibration: SLSTR Oblique view shifted from 2 pixels SLSTR co-registration between SWIR and VIS channels 3. Regular verification of SYN L1 processing 4. On-going verification of SYN L2 processing 20

21 Status of SYN L2 Processing chain Checking of SYN L2 products: Understanding of the obtained patterns with regards to the included algorithms Verification of the SYN L2 flags Checking of the SYN L2 algorithm Aerosol retrieval Cosmetic Filling 21

22 SYN L2 reflectance OLCI O17 band at 865 nm SLSTR S3 band at 865 nm 2) 1) 22

23 Zone 1 ACRI-ST S3MPC Proba-V QWG - ESRIN ACRI-ST 24-Nov-16 23

24 Zone 2 Square patterns 24

25 Aerosol Optical thickness 25

26 Same pattern for A550 Handling of partly_water boxes in the processing? Inter-camera visible? 26

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28 SYN L2 flags Specification evolutions: - Definition of the macro-pixels - 100% filled with land and cloud free pixels - Keeping only the SLSTR «land» Cloud flags? - Cosmetic filling = Weighted average of 240*240 valids neighbours 28