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An Regional Enemble Kalman Filter Data Assimilation System Employing GSI Observation Processing and Initial Tests for Rapid Refresh Forecast Configurations. Kefeng Zhu, Yujie Pan, Xue Ming and Xuguang Wang CAPS. Code development status.
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An Regional EnembleKalman Filter Data Assimilation System Employing GSI Observation Processing and InitialTests for Rapid Refresh Forecast Configurations Kefeng Zhu, Yujie Pan, Xue Ming and Xuguang Wang CAPS
Code development status • EnKFv1----we modified the global EnSRF code from Dr. Jeff Whitaker of ESRL and linked this EnSRF package with the regional GSI for RR application. • EnKFv2---- we merged regional EnKF with the latest global EnKF, by moving codes specific to regional EnKF into a unified version. And a new flag ‘iflagreg’ was added to control the regional analysis option. In this unified version, the variables updated during the regional EnKF assimilation were x-component wind (U), y-component wind (V), potential temperature (T), perturbation geopotential(PH, not used in the previous EnKFv1), water vapor mixing ratio (Q) and perturbation dry air mass in column (Mu). • EnKFv3----instead of interpolating the U and V to the A grid during the EnKF analysis process, we keep the U and V in the original C grids
~13km Rapid Refresh(RR) Diabatic integration Full physics integration
Domains EnKF Test Domain 207x207 grid points ~40 km, 51 levels The 13 km RR-like forecast Domain 532x532 grid points ~13 km, 51 levels Current RUC Domain as indicated EnSRF EnSRF—RR RUC
284/184 287/187 281/181 ADPSFC ADPSFC ADPSFC Observation type used for verification Surface: Land--- 287,281,284 (U,V) 187,181,184 (RH,T,PRMSL) Sea---280,282 (U,V) 180 (RH,T,PRMSL) Up air: 220,221,223 (U,V) 120 (RH,T,PRMSL) Quality mark: 2 282 280/180 SFCSHP SFCSHP 221 223 220/120 PROFLR ADPUPA ADPUPA
Inflation factors and horizontal cutoff radius configuration test Note: Here the EnKF comes from the 40 members 3-h forecast ensemble mean; GSI is a single deterministic forecast. The verification period are from 00 UTC May 8 ~ 06 UTC May 16, 2010. There are 66 samples collected for the observation type ADPSFC, SFCSHP, PROFLR, but 16 samples for the ADPUPA
Inflation algorithms • Simple covariance • State-dependent covariance inflation • Double inflation taper(r)
RH---ADPUPA U---PROFLR U---ADPUPA T---ADPUPA V---ADPUPA V---PROFLR
Vertical and horizontal cutoff radius setting test Note: Here the EnKF comes from the 40 members 3-h forecast ensemble mean; GSI is a single deterministic forecast. The verification period are from 00 UTC May 8 ~ 06 UTC May 16, 2010. There are 66 samples collected for the observation type ADPSFC, SFCSHP, PROFLR, but 16 samples for the ADPUPA
RH---ADPUPA U---PROFLR U---ADPUPA T---ADPUPA V---ADPUPA V---PROFLR
EnKFdfi20m40s3600s/GSI/GFS EnKFdfi40m60s3600s EnKFdfi40m40s2800s
RH---ADPUPA U---PROFLR U---ADPUPA T---ADPUPA V---ADPUPA V---PROFLR
Longer hour single forecast from ensemble mean analyses sea land Surface verification: The plots above are the average forecasts innovation of single forecast from ensemble mean analyses for the time period from 00UTC May 8 to 03 UTC May 16, 2010. The cycle interval is 3 hours. Totally, there are 66 samples for this statistic. Up air verification: since the observation of ADPUPA are only available at 00, 12 Z. Therefore, for the vertical profile followed, we average the 12 hour forecasts innovation from 00, 12Z. There are totally 17 samples.
Temperature at 2m-Land Temperature at 2m-Sea RH at 2m-Land RH at 2m-Sea
U at 10m-Land U at 10m-Sea V at 10m-Land V at 10m-Sea
3h 6h 9h RH 18h 12h 15h
3h 6h 9h Tmperature 18h 12h 15h
3h 6h 9h UGRD---ADPUPA 18h 12h 15h
3h 6h 9h VGRD---ADPUPA 18h 12h 15h
3h 6h 9h UGRD---PROFLR 18h 12h 15h
3h 6h 9h VGRD---PROFLR 18h 12h 15h
13 km Verification followed Against Stage IV---GSS(ETS)
Stage IV GSI based forecast EnKF based forecast 00~12 UTC May 10,2010 00~12 UTC May 11,2010 00~12 UTC May 13,2010