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 Alerts are provided for information on an as-is basis and may be withdrawn or changed without notice.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 2019-09-21 00:00

amsua
NOAA-19/AMSUA RADIANCES (10 channels affected) : out of range
Considerable: obs_number=3954.0000, expected range: 4323.6945 5666.4166
iasi
All METOP-A/IASI RADIANCES ALL CHANNELS Global : all data missing
Severely_persistent: obs_number=0, expected range: 0.00 26366.64
METOP-C/IASI RADIANCES (210 channels affected) : out of range
Severe: obs_number=82233.0000, expected range: 107914.9105 134615.7922
gpsro
All TERRASAR-X SETTING ALL HEIGHTS Global : all data missing
Severely_persistent: obs_number=0, expected range: 0.00 1487.82
All TANDEM-X RISING ALL HEIGHTS Global : all data missing
Severely_persistent: obs_number=0, expected range: 0.00 1107.20
Atmospheric Motion Vector
METOP-A/AMV IR WIND VECTOR DIFF (M/S) PRESSURE LAYER 300-600 (HPA) : out of range
Considerable: stdev_press=92.9076, expected range: 52.5279 82.4986
METOP-B/AMV IR WIND VECTOR DIFF (M/S) PRESSURE LAYER 300-600 (HPA) : out of range
Considerable: stdev_press=96.0601, expected range: 53.5958 84.8012
Radiosondes
HIGH RESO LAND TEMP Q (G/KG) (3 pressure layers affected) : out of range
Considerable: obs_number=2483.0000, expected range: 1821.6813 2216.0965
HIGH RESO SEA TEMP Q (G/KG) PRESSURE LAYER 0-300 (HPA) : out of range
Considerable: rms_fgdepar=0.0345, expected range: 0.0000 0.0218
amdar
WIGOS AMDAR TEMPERATURE (K) PRESSURE LAYER 600-900 (HPA) : out of range
Considerable: rms_fgdepar=1.9020, expected range: 0.3976 1.3332
pilot
BUFR LAND PILOT WIND VECTOR DIFF (M/S) PRESSURE LAYER 0-300 (HPA) : out of range
2 times in the last 10 days for at least one item
Considerable: rms_fgdepar=7.3706, expected range: 1.8541 5.1188
Slight: avg_fgdepar=5.5269, expected range: 1.5686 4.4225
synop
BUFR LAND SYNOP SURFACE PRESSURE (PA) : out of range
3 times in the last 10 days for at least one item
Considerable: avg_biascorr=1.4545, expected range: 5.8330 11.6885
buoy
MOORED BUOYS WIND VECTOR DIFF (M/S) : out of range
4 times in the last 10 days for at least one item
Severe: obs_number=222.0000, expected range: 189.4245 197.1160