sss maps derived from l1 v500 and l1 reprocessing commissionning and l2 v500
DESCRIPTION
SSS maps derived from L1 v500 and L1 reprocessing commissionning and L2 v500. J. Boutin, N. Martin, X. Yin. Data Processing. July 2010 L1 v500 Sun Off & L1 Commissionning Reprocessing November 2010 L1 Commissionning Reprocessing L2 v500 reprocessed at LOCEAN Tested L2 flags - PowerPoint PPT PresentationTRANSCRIPT
SSS maps derived from L1 v500 and L1 reprocessing
commissionning and L2 v500
J. Boutin, N. Martin, X. Yin
July 2010 L1 v500 Sun Off & L1 Commissionning ReprocessingNovember 2010 L1 Commissionning Reprocessing
L2 v500 reprocessed at LOCEANTested L2 flagsCTRL_SEL_GP;CTRL_VALID;CTRL_ECMWF = 1 CTRL_NUM_MEAS_MIN;CTRL_MANY_OUTLIERS;CTRL_SUNGLINT;CTRL_MOONGLINT;CTRL_GAL_NOISE;CTRL_REACH_MAXITER;CTRL_MARQ;CTRL_CHI2_P;CTRL_CHI2;CTRL_SUSPECT_RFI = 0
Data Processing
SSS maps computation
• 1°x1° SSS maps computed from averages of SMOS SSS weighted by their spatial resolution R2 and variance of the error 2 (derived by the retrieval):
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L1 v500 sun off
L1 Commissionning Reprocessing
L2 v500 Ascending swaths SSS Center swath July
L2 v500 Descending swaths SSS Center swath July
L1 v500 sun off
L1 Commissionning Reprocessing
L1 v500 sun off
L1 v500 Sun on or Sun off - L2 v500 Ascending swaths SSS Center swath July
L1 v500 sun on
L2 v500 Descending swaths SSS Center swath July
L1 v500 sun off
L1 v500 sun on
More stripes on L1 sun on than on L1 sun off on descending orbits! (look at the southern ocean)
L1 v500 sun off – L2 v500 Asc SSS
Error on WS 2m/sWhole swath
Center swath +/-300km
RFI better sorted out at the center of the swath
L1 v500 sun off – L2 v500 Asc N
Error on WS 2m/sWhole swath
Central swath +/-300km
L1 v500 sun off – L2 v500 Desc SSS
Error on WS 2m/sWhole swath
Central swath +/-300km
RFI better sorted out at the center of the swath
L1 v500 sun off – L2 v500 Desc N
Error on WS 2m/sWhole swath
Central swath +/-300km
Comparison with ARGOL2 V317-August 2010
SMOS -CLIMATO ARGO -CLIMATO
SMOS-ARGOSSS anomalies seen by ARGO in tropical Pacific seen by SMOS butPbs close to land, icePbs at high wind speed (see next slide), anomaly in Pacific ITCZ more negative on SMOS
Boutin et al., subm, 2011
South Pacific: SSS=0.09+/-0.56N=160
ITCZ trop Pac N:SSS=-0.18+/-0.44N=236
SMOS L2v317 - ARGO SSS (3-31 August 2010; asc orbits) versus wind speed (center of orbit)
South Indian:SSS=0.11+/-0.46N=50
Subtropical Atl N:SSS=0.1+/-0.35N=59
Colocation radii: +/-5days; +/-50km
Statistics computed after averaging over +/-5days; +/-50km over 3-12m s-1
Comparison with ARGOL1 ~v500 – L2 V500 - July 2010
SMOS -CLIMATO ARGO -CLIMATO
SMOS-ARGO
SSS too high close to ice, too low close to land
South Pacific: SSS=0.16+/-0.63N=186
ITCZ trop Pac N:SSS=-0.05+/-0.40N=248
SMOS L1v500 sun off- L2v500 - ARGO SSS (July 2010; asc orbits) versus wind speed (center of orbit)
South Indian:SSS=0.06+/-0.56N=52
Subtropical Atl N:SSS=0.02+/-0.22N=69
Colocation radii: +/-5days; +/-50kmStatistics computed after averaging over +/-5days; +/-50km over 3-12m s-1
Reduced biases wrt to commissionning reprocessing but very large std in South Pacific (cold region); in southern hemisphere bias between asc and desc
South Pacific: SSS=0.27+/-0.70N=170
ITCZ trop Pac N:SSS=0.01+/-0.43N=230
SMOS L1v500 sun on L2v500 - ARGO SSS (1-27July 2010; asc orbits) versus wind speed (center of orbit)
South Indian:SSS=0.21+/-0.55N=48
Subtropical Atl N:SSS=0.19+/-0.22N=65
Colocation radii: +/-5days; +/-50kmStatistics computed after averaging over +/-5days; +/-50km over 3-12m s-1
Very large std in South Pacific; no noticeable improvement wrt v500 sun off (even worse);in southern hemisphere bias between asc and desc
South Pacific: SSS=-0.27+/-0.85N=188
ITCZ trop Pac N:SSS=-0. 06+/-0.45N=248
South Indian:SSS=-0.14+/-0.38N=52
Subtropical Atl N:SSS=0.06+/-0.32N=67
Statistics computed after averaging over +/-5days; +/-50km over 3-12m s-1
SMOS L1v500 sun off- L2v500 - ARGO SSS (July 2010; desc orbits)
versus wind speed (center of orbit)
Very large std in South Pacific; in southern hemisphere bias between asc and desc
South Pacific: SSS=-0.15+/-0.78N=156
ITCZ trop Pac N:SSS=0. 02+/-0.51N=233
South Indian:SSS=-0.03+/-0.35N=49
Subtropical Atl N:SSS=0.23+/-0.33N=67
Statistics computed after averaging over +/-5days; +/-50km over 3-12m s-1
SMOS L1v500 sun on- L2v500 - ARGO SSS (July 2010; desc orbits)
versus wind speed (center of orbit)
Very large std in South Pacific; no noticeable improvement wrt v500 sun off;in southern hemisphere bias between asc and desc
Conclusions
• L1 v500 sun off much better than L1 commissionning reprocessing
• L1 v500 sun on does not perform better than L1 v500 sun off (even worse) ! Preliminary results; need to be consolidated on November v500!
• RFI flag works better at the center of the swath (+/-300km) than at the edge of the swath
Flags and SMOS_MODE
• Oceanographers implicated in SMOS_MODE have asked for recommendations about flags to be used Do we agree on recommending to apply:
• CTRL_SEL_GP;CTRL_VALID;CTRL_ECMWF = 1 • CTRL_NUM_MEAS_MIN;CTRL_MANY_OUTLIERS;CTRL_SUNGLINT;CTRL_MOO
NGLINT;CTRL_GAL_NOISE;CTRL_REACH_MAXITER;CTRL_MARQ;CTRL_CHI2_P;CTRL_CHI2;CTRL_SUSPECT_RFI = 0
• Add recommendation beginning of ATBD? (looking in ATBD, I haven’t find description of ctrl_poor_geophys and ctrl_poor_retrieval)
L1 Commissionning reprocessing – L2 v500 Asc July
Whole swath
Center swath
L1 Commissionning reprocessing – L2 v500 Desc July
Whole swath
Center swath
L1 commissionning reprocessing-L2 v500November (center swath -Asc)
OTT Nov
OTT July
L1 commissionning reprocessing-L2 v500November (center swath - Desc)
OTT Nov
OTT July