Status on cycle 127 Saral

Cycle lasts from 2019-02-04 16:43:53 to 2019-03-11 16:51:30.

Processing on SSALTO on 8th April (with L1 library=V4.7, L2 library=V5.5p2, Processing Pilot=V5-2p2).

Quality assement report is available here.

Particular events on cycle

During this cycle HD mode was activated (during 1s) at the following:

    - 12/02/2019 at 22:16:47

    - 13/02/2019 at 10:40:08

    - 28/02/2019 at 22:17:26

    - 01/03/2019 at 10:40:46.

Acquisition/tracking modes

During cycle 127 only one acquisition/tracking mode was used:

          - Passes 1 to 1002 : DIODE acquisition / median tracking

Missing ocean data

Some passes have a large number of missing measurements. Are presented here the passes with more than 10% of missing data :

  

Pass number 1 2 3 4 5 6-23 24 34 35 36-46 66 67 68 69
% missing measurements 12,13  71,18  19,75  89,15  28,08  100  31,44  22,49  45,19  100  14,47  20,94  58,57  98,80 

 

Pass number 70 7194 95111 113114 115116 117152 239
% missing measurements 100  58,73 12,93  10,94 10,00  17,92 48,26  31,48 38,19  47,38 10,37  100 

 

Pass number259 260 261 262 263 264 265 266-270 271 296 382 407
% missing measurements 12,76  12,48  24,53  31,53  44,10  53,80  68,00  100  48,55  13,13  14,14  12,92 

 

Pass number 409 410 451 453 479
% missing measurements 13,58  15,09  14,56  12,45  10,13 

 

The overall percentage of ocean missing measurements (latitude < 50 deg, bathy < -1000m) on this cycle: 5.62% (usually between 0.06% and 0.08%).

Calval output

During this cycle mispointing has reached levels that has not been observed since the pre-SHM period (September 2014).

These levels of mispointing are due to attitude deviation, and explains the higher percentage of missing measurements.

Data quality is severely impacted by these events, so that more than 40% of the data is invalid  because of mispointing. (see attached figures).

Users are advised to use data with off_nadir_angle < 0.09deg².

Performances

Xover rms =  5.29 cm (latitude < 50 deg, bathy < -1000m , low variability areas , excluding edited data)

SLA rms = 10.05 cm  

Conclusion

Cycle certified for distribution from CALVAL point of view, with a restriction : use data with off_nadir_angle < 0.09deg²