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PEODAS. Oscar Alves, Yonghong Yin, Robin Wedd, Maggie Zhao and Harry Hendon CAWCR. The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology. Plan. Introduction to PEODAS Impact on Forecast Skill (vs Old System)
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PEODAS Oscar Alves, Yonghong Yin, Robin Wedd, Maggie Zhao and Harry Hendon CAWCR The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Plan Introduction to PEODAS Impact on Forecast Skill (vs Old System) Comparison with other Centres The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
PEODAS (Yin et al 2010) Pseudo Ensemble Kalman Filter – (Based on extension of BLUElink system; Oke et al) 11 member ensemble but used lagged set for covariances (100 member) Compression to central rather than assimilation into each Constant background/obs error ratio (not using ensemble) Background covariance only used from ensemble The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Comparison with POAMA-1 POAMA-1 PEODAS System Optimum Interpolation Pseudo EnKF Covariances 2D Univariate Static 3D Multi-variate Time-evolving Observations Temperature profiles from BoM Temperature and salinity profiles from EU ENACT Forcing NCEP Re-analysis ERA-40 Re-analysis Bias Correction 3D relaxation to Levitus None Re-analysis 1960-present 1980-present The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Example of Ensemble Spread (Estimate of analysis error) Temperature Salinity From Yin et al 2010 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Correlation between re-analysis and UKMO EN3 dataset Heat Content Salt Content Produced by Maggie Zhao The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Impact on Forecasts (& Comparison with other models) Mostly Based on hind-casts from ~1982-2006 The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
NINO 3 and IOD Skill POAMA-2 Produced by Li Shi The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Impact of Assimilation on Heat Content Skill Correlation in Tropics POAMA-2 (3 models) No Assim POAMA-1.5 Produced by Maggie Zhao The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Impact of Assimilation on Salt Content Skill Correlation in Tropics No Assim POAMA-2 (3 models) POAMA-1.5 Produced by Maggie Zhao The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Salinity Correlation Old Forecasts PEODAS Forecasts PEODAS OBS OLD OI OBS EN3 OBS The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Temperature Correlation Old Forecasts PEODAS Forecasts PEODAS OBS OLD OI OBS EN3 OBS The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Comparison of re-analyses with other centres The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Comparison with Other Centres Correlation with “Observations” Heat Content Surface Current PEODAS ECMWF Produced by Maggie Zhao The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
ENSO Composite Heat Content Produced by Li Shi The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
ENSO Composite Heat Content Surface Salinity PEODAS ECMWF NCEP Produced by Li Shi The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
IOD Composite Heat Content Surface Salinity PEODAS ECMWF GODAS (NCEP) EN3 Produced by Li Shi The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology
Summary • PEODAS assimilation shows good agreement with obs and competitive with other systems • Skill improvement for NINO3 (IOD ?) • Sub-surface skill better compared to NINO3 • But sub-surface skill, especially salinity, depends on observed dataset • (Similar problem looking Great Barrier Reef SST Skill) • What is reality? The Centre for Australian Weather and Climate Research A partnership between CSIRO and the Bureau of Meteorology