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 Alerts are provided for information on an as-is basis and may be withdrawn or changed without notice.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 2019-09-15 12:00

cris
NPP/CRIS RADIANCES (157 channels affected) : out of range
Severe: obs_number=22388.0000, expected range: 97667.2431 149984.3569
NPP/CRIS RADIANCES CHANNEL 653 : out of range
1 times in the last 10 days for at least one item
Slight: avg_fgdepar=0.1731, expected range: -0.1613 0.1371
NPP/CRIS RADIANCES CHANNEL 657 : out of range
1 times in the last 10 days for at least one item
Slight: avg_fgdepar=0.1704, expected range: -0.1549 0.1318
mhs
ALLSKY METOP-A/MHS RADIANCES CHANNEL 3 : out of range
Severe: obs_number=11989.0000, expected range: 14327.6563 17234.7761
ALLSKY METOP-A/MHS RADIANCES CHANNEL 4 : out of range
Severe: obs_number=11816.0000, expected range: 14166.3100 17008.8251
ALLSKY METOP-A/MHS RADIANCES CHANNEL 2 : out of range
Slight: obs_number=19026.0000, expected range: 19968.5854 24174.8201
Radiosondes
All LAND TEMP WIND VECTOR DIFF (M/S) ALL LAYERS WMO BLOCK 16 : all data missing
Severe: obs_number=0, expected range: 36.28 117.94
HIGH RESO LAND TEMP TEMPERATURE (K) (4 pressure layers affected) : out of range
Severe: obs_number=95.0000, expected range: 187.2059 197.2385
HIGH RESO LAND TEMP Q (G/KG) (4 pressure layers affected) : out of range
Severe: obs_number=66.0000, expected range: 113.1689 149.8311
HIGH RESO LAND TEMP TEMPERATURE (K) PRESSURE LAYER 900-1200 (HPA) : out of range
Considerable: rms_fgdepar=2.7327, expected range: 0.0000 1.6799
buoy
DRIFTING BUOYS SURFACE PRESSURE (PA) : out of range
Severe: avg_biascorr=-11.2000, expected range: 0.0000 0.0000