Last updated Feb 2013
|Data assimilation method|
|AMV types assimilated|
|Blacklisting in space|
No QI thresholds applied to the polar data.
extratropics: polewards of 20S/N
hl: 10-400 hPa
ml: 400-700 hPa
ll: 700-1000 hPa
QI1 - EUMETSAT QI with first guess check
QI2 - EUMETSAT QI without first guess check
RFF - Recursive Filter Function (CIMSS/NESDIS)
For information on how the quality indicators are formulated see Holmlund (1998, Weather Forecasting 13 1093-1104) and Hayden and Purser (1995, Journal of Applied Meteorology 34 3-15).
Observation errors calculated individually for each wind using estimates of the error in vector, error in height and variation in the background wind column. For more information see AMV errors: a new approach in NWP (9IWW paper).
The mean profile and zonal plots in the table below give an indication of the typical observation errors used. Statistics calculated for June 2012 with QI2 > 80.
|History of Changes|
|The list includes the main AMV or model changes implemented operationally
in the Met Office global model.|