Operational Data Checking

An automatic data checking system has been implemented at ECMWF to trigger warnings in case of anomalies affecting the quality or the availability of the data assimilated by the model. Selected statistical parameters (number of observations, bias correction, and mean bias-corrected background, analysis departures and probability of gross error) are checked against an expected range. An appropriate alert message (including a time series plot) is generated if statistics are outside the specified ranges. A severity level (slight, considerable, severe) is assigned to each message depending on how far statistics are from the expected values. Two kinds of ranges are used by the automatic checking: Soft and Hard limits. Soft limits are updated automatically using statistics from the last twenty days (extremes are excluded during this process). Hard limits are adjusted manually when required.

Currently, the automatic checking is limited to data passing through the minimisation process (including VarBC passive data). It's being applied twice a day to the delayed cut-off 4D-VAR cycles (00 and 12) and four times a day to the early delivery assimilation system (00,06,12 and 18).

The alarm system results are based on feedback information from the ECMWF data assimilation and consequently reflect the ECMWF data usage. Although most warnings are related to data problems, they may on occasion also be related to model issues. Alerts are provided for information on an as-is basis and may be withdrawn or changed without notice. ECMWF accepts no responsibility for actions taken on the basis of these results.

Ensemble Data Assimilation at 2019-09-16 12:00

cris
NPP/CRIS RADIANCES (157 channels affected) : out of range
1 times in the last 10 days for at least one item
Severe: obs_number=22374.0000, expected range: 97667.2431 149984.3569
mhs
ALLSKY METOP-A/MHS RADIANCES (5 channels affected) : out of range
Considerable: obs_number=25639.0000, expected range: 27264.8825 30798.1175
atms
NPP/ATMS RADIANCES (7 channels affected) : out of range
Considerable: obs_number=3609.0000, expected range: 2885.2746 3425.1825
ssmis
DMSP-18/SSMIS RADIANCES CHANNEL 4 : out of range
15 times in the last 10 days for at least one item
Severely_persistent: stdev_norm_fgdepar=0.0094, expected range: 0.0112 0.0145
DMSP-18/SSMIS RADIANCES CHANNEL 5 : out of range
15 times in the last 10 days for at least one item
Severely_persistent: stdev_norm_fgdepar=0.0093, expected range: 0.0111 0.0146
gpsro
All TERRASAR-X SETTING ALL HEIGHTS Global : all data missing
Severe: obs_number=0, expected range: 0.00 1436.29
All TANDEM-X RISING ALL HEIGHTS Global : all data missing
Severe: obs_number=0, expected range: 13.73 1129.85
Atmospheric Motion Vector
GOES-16/AMV VIS1 WIND VECTOR DIFF (M/S) PRESSURE LAYER 600-900 (HPA) : out of range
Considerable: avg_fgdepar=2.0293, expected range: 1.6455 1.9524
Radiosondes
DROP SONDE Q (G/KG) PRESSURE LAYER 300-600 (HPA) : missing
Severe: obs_number=0.0000, expected range: 0.0000 846.9427
synop
BUFR LAND SYNOP RH2M (%) : out of range
7 times in the last 10 days for at least one item
Severely_persistent: obs_number=101.0000, expected range: 102.0000 102.0000
Severely_persistent: obs_number=48.0000, expected range: 54.7665 60.6452
buoy
DRIFTING BUOYS SURFACE PRESSURE (PA) : out of range
3 times in the last 10 days for at least one item
Severe: avg_biascorr=-2.2642, expected range: 0.0000 0.0000