Coupled assimilation for an intermediated coupled ENSO prediction model
Tóm tắt
The value of coupled assimilation is discussed using an intermediate coupled model in which the wind stress is the only atmospheric state which is slavery to model sea surface temperature (SST). In the coupled assimilation analysis, based on the coupled wind–ocean state covariance calculated from the coupled state ensemble, the ocean state is adjusted by assimilating wind data using the ensemble Kalman filter. As revealed by a series of assimilation experiments using simulated observations, the coupled assimilation of wind observations yields better results than the assimilation of SST observations. Specifically, the coupled assimilation of wind observations can help to improve the accuracy of the surface and subsurface currents because the correlation between the wind and ocean currents is stronger than that between SST and ocean currents in the equatorial Pacific. Thus, the coupled assimilation of wind data can decrease the initial condition errors in the surface/subsurface currents that can significantly contribute to SST forecast errors. The value of the coupled assimilation of wind observations is further demonstrated by comparing the prediction skills of three 12-year (1997–2008) hindcast experiments initialized by the ocean-only assimilation scheme that assimilates SST observations, the coupled assimilation scheme that assimilates wind observations, and a nudging scheme that nudges the observed wind stress data, respectively. The prediction skills of two assimilation schemes are significantly better than those of the nudging scheme. The prediction skills of assimilating wind observations are better than assimilating SST observations. Assimilating wind observations for the 2007/2008 La Niña event triggers better predictions, while assimilating SST observations fails to provide an early warning for that event.
Tài liệu tham khảo
citation_journal_title=Quart J Roy Meteor Soc; citation_title=Sensitivity of dynamical seasonal forecasts to ocean initial conditions; citation_author=O Alves, M Balmaseda, D Anderson, T Stockdale; citation_volume=130; citation_publication_date=2004; citation_pages=647-668; citation_doi=10.1256/qj.03.25; citation_id=CR1
citation_journal_title=J Clim; citation_title=Application of a reduced-order Kalman filter to initialize a coupled atmosphere–ocean model: impact on the prediction of El Niño; citation_author=J Ballabrera-Poy, AJ Busalacchi, R Murtugudde; citation_volume=14; citation_publication_date=2001; citation_pages=1720-1737; citation_doi=10.1175/1520-0442(2001)014<1720:AOAROK>2.0.CO;2; citation_id=CR2
citation_journal_title=J Phys Oceanogr; citation_title=Diagnostic model and analysis of the surface currents in the Tropical Pacific Ocean; citation_author=F Bonjean, GSE Lagerloef; citation_volume=32; citation_publication_date=2002; citation_pages=2938-2954; citation_doi=10.1175/1520-0485(2002)032<2938:DMAAOT>2.0.CO;2; citation_id=CR3
citation_journal_title=J Clim; citation_title=Impact of ECCO ocean-state estimates on the initialization of seasonal climate forecasts; citation_author=G Cazes-Boezio, D Menemenlis, CR Mechoso; citation_volume=21; citation_publication_date=2008; citation_pages=1929-1947; citation_doi=10.1175/2007JCLI1574.1; citation_id=CR4
citation_journal_title=J Clim; citation_title=A hybrid coupled model study of tropical Atlantic variability; citation_author=P Chang, L Ji, R Saravanan; citation_volume=14; citation_publication_date=2001; citation_pages=361-390; citation_doi=10.1175/1520-0442(2001)013<0361:AHCMSO>2.0.CO;2; citation_id=CR5
citation_journal_title=J Comput Phys; citation_title=El Niño prediction and predictability; citation_author=DC Chen, MA Cane; citation_volume=227; citation_publication_date=2008; citation_pages=3625-3640; citation_doi=10.1016/j.jcp.2007.05.014; citation_id=CR6
citation_journal_title=Mon Wea Rev; citation_title=Initialization and predictability of a coupled ENSO forecast model; citation_author=D Chen, SE Zebiak, MA Cane, AJ Busalacchi; citation_volume=125; citation_publication_date=1997; citation_pages=773-788; citation_doi=10.1175/1520-0493(1997)125<0773:IAPOAC>2.0.CO;2; citation_id=CR7
citation_journal_title=Nature; citation_title=Predictability of El Niño in the past 148 years; citation_author=D Chen, MA Cane, A Kaplan, SE Zebiak, D Huang; citation_volume=428; citation_publication_date=2004; citation_pages=733-736; citation_doi=10.1038/nature02439; citation_id=CR8
citation_journal_title=Ocean Dyn; citation_title=Sampling strategies and square root analysis schemes for the EnKF; citation_author=G Evensen; citation_volume=54; citation_publication_date=2004; citation_pages=539-560; citation_doi=10.1007/s10236-004-0099-2; citation_id=CR9
citation_title=Data assimilation: the ensemble Kalman Filter; citation_publication_date=2009; citation_id=CR10; citation_author=G Evensen; citation_publisher=Springer
citation_journal_title=Quart J Roy Meteor Soc; citation_title=Atmospheric and surface variations during westerly wind bursts in the tropical western Pacific; citation_author=J Fasullo, P Webster; citation_volume=126; citation_publication_date=2000; citation_pages=899-924; citation_doi=10.1256/smsqj.56406; citation_id=CR11
citation_journal_title=J Clim; citation_title=Coupled climate simulation by constraining ocean fields in a coupled model with ocean data; citation_author=Y Fujii, T Nakaegawa, S Matsumoto, T Yasuda, G Yamanakai, M Kamachi; citation_volume=22; citation_publication_date=2009; citation_pages=5541-5557; citation_doi=10.1175/2009JCLI2814.1; citation_id=CR12
citation_title=Ensemble-based atmospheric data assimilation; citation_inbook_title=Predictability of weather and climate. chap. 6; citation_publication_date=2006; citation_pages=124-156; citation_id=CR13; citation_author=TM Hamill; citation_publisher=Cambridge Univ. Press
citation_journal_title=Mon Wea Rev; citation_title=Impact of data assimilation on ocean initialization and El Niño prediction; citation_author=M Ji, A Leetma; citation_volume=125; citation_publication_date=1997; citation_pages=742-753; citation_doi=10.1175/1520-0493(1997)125<0742:IODAOO>2.0.CO;2; citation_id=CR14
citation_journal_title=Clim Dyn; citation_title=Current status of ENSO prediction skill in coupled ocean–atmosphere models; citation_author=EK Jin, LK James, B Wang, CK Park, IS Kang, BP Kirtman, JS Kug, A Kumar, JJ Luo, J Schemm, J Shukla, T Yamagata; citation_volume=31; citation_publication_date=2008; citation_pages=647-664; citation_doi=10.1007/s00382-008-0397-3; citation_id=CR15
citation_journal_title=Geophys Res Lett; citation_title=An El Niño prediction system using an intermediate ocean and a statistical atmosphere; citation_author=IS Kang, JS Kug; citation_volume=27; citation_publication_date=2000; citation_pages=1167-1170; citation_doi=10.1029/1999GL011023; citation_id=CR16
citation_journal_title=Mon Wea Rev; citation_title=Error covariance modeling in the GMAO ocean ensemble Kalman filter; citation_author=CL Keppenne, MM Rienecker, JP Jacob, R Kovach; citation_volume=136; citation_publication_date=2008; citation_pages=2964-2982; citation_doi=10.1175/2007MWR2243.1; citation_id=CR17
Keenlyside NS, Kleeman R (2002) Annual cycle of equatorial zonal currents in the Pacific. J Geophys Res 107. doi:
10.1029/2000JC0007111
citation_journal_title=Mon Wea Rev; citation_title=The COLA anomaly coupled model: ensemble ENSO prediction; citation_author=BP Kirtman; citation_volume=131; citation_publication_date=2003; citation_pages=2324-2341; citation_doi=10.1175/1520-0493(2003)131<2324:TCACME>2.0.CO;2; citation_id=CR19
citation_journal_title=Geophys Res Lett; citation_title=Impact of the model assimilated wind stress data in the initialization of an intermediate ocean model and the ENSO predictability; citation_author=JS Kug, IS Kang, SE Zebiak; citation_volume=28; citation_publication_date=2001; citation_pages=3713-3717; citation_doi=10.1029/2000GL012793; citation_id=CR20
citation_journal_title=Geophys Res Lett; citation_title=State-dependent atmospheric noise associated with ENSO; citation_author=JS Kug, FF Jin, KP Sooraj, IS Kang; citation_volume=35; citation_publication_date=2008; citation_pages=L05701; citation_doi=10.1029/2007GL032017; citation_id=CR21
citation_journal_title=Clim Dyn; citation_title=Triggering of El Niño by westerly wind events in a coupled general circulation model; citation_author=M Lengaigne, E Guilyardi, JP Boulanger, C Menkes, P Inness; citation_volume=23; citation_publication_date=2004; citation_pages=601-620; citation_doi=10.1007/s00382-004-0457-2; citation_id=CR22
Levitus S (1982) Climatological atlas of the world ocean. NOAA Prof. Paper 13, 173 pp and 17 microfiche
citation_journal_title=J Math Phys Sci; citation_title=A linear stratified ocean model of the equatorial undercurrent. Philosophical transactions of the Royal Society of London; citation_author=JP McCreary; citation_volume=298; citation_publication_date=1981; citation_pages=603-635; citation_id=CR24
citation_journal_title=Science; citation_title=Genesis and evolution of the 1997–1998 El Niño; citation_author=MJ McPhaden; citation_volume=283; citation_publication_date=1999; citation_pages=950-954; citation_doi=10.1126/science.283.5404.950; citation_id=CR25
citation_journal_title=Bull Am Meteorol Soc; citation_title=Evolution of the 2002/03 El Niño; citation_author=MJ McPhaden; citation_volume=85; citation_publication_date=2004; citation_pages=677-695; citation_doi=10.1175/BAMS-85-5-677; citation_id=CR26
Monterey GI, Levitus S (1997) Climatological cycle of mixed layer depth in the world ocean. US Gov. Printing Office, NOAA NESDIS, 5 pp
citation_journal_title=J Clim; citation_title=The non-normal nature of El Niño and intraseasonal variability; citation_author=A Moore, R Kleeman; citation_volume=12; citation_publication_date=1999; citation_pages=2965-2982; citation_doi=10.1175/1520-0442(1999)012<2965:TNNOEN>2.0.CO;2; citation_id=CR28
citation_journal_title=J Clim; citation_title=The role of atmospheric dynamics and non-normality in controlling optimal perturbation growth in coupled models of ENSO; citation_author=AM Moore, J Vialard, A Weaver, DLT Anderson, R Kleeman, JR Johnson; citation_volume=16; citation_publication_date=2003; citation_pages=951-968; citation_doi=10.1175/1520-0442(2003)016<0951:TROASI>2.0.CO;2; citation_id=CR29
citation_journal_title=Tellus; citation_title=On extending the limits of variational assimilation in nonlinear chaotic systems; citation_author=C Pires, R Vautard, O Talagrand; citation_volume=48; citation_publication_date=1996; citation_pages=96-121; citation_doi=10.1034/j.1600-0870.1996.00006.x; citation_id=CR30
citation_title=The atmospheric general circulation model ECHAM-4: model description and simulation of present-day climate; citation_publication_date=1996; citation_id=CR31; citation_author=E Roeckner; citation_author=K Arpe; citation_author=L Bengtsson; citation_author=M Christoph; citation_author=M Claussen; citation_author=L Dümenil; citation_author=M Esch; citation_author=M Giorgetta; citation_author=U Schlese; citation_author=U Schulzweida; citation_publisher=Max-Planck Institute for Meteorology
citation_journal_title=Mon Wea Rev; citation_title=The impact of ocean initial conditions on ENSO forecasting with a coupled model; citation_author=A Rosati, K Miyakoda, R Gudgel; citation_volume=125; citation_publication_date=1997; citation_pages=754-772; citation_doi=10.1175/1520-0493(1997)125<0754:TIOOIC>2.0.CO;2; citation_id=CR32
citation_journal_title=Mon Wea Rev; citation_title=Implications of the form of the ensemble transformations in the ensemble square root filters; citation_author=P Sakov, PR Oke; citation_volume=136; citation_publication_date=2008; citation_pages=1042-1053; citation_doi=10.1175/2007MWR2021.1; citation_id=CR33
citation_journal_title=J Atmos Sci; citation_title=Instability of the chaotic ENSO: the growth-phase predictability barrier; citation_author=RM Samelson, E Tziperman; citation_volume=58; citation_publication_date=2001; citation_pages=3613-3625; citation_doi=10.1175/1520-0469(2001)058<3613:IOTCET>2.0.CO;2; citation_id=CR34
citation_journal_title=Mon Wea Rev; citation_title=Ocean data assimilation, initialization and prediction of ENSO with a coupled GCM; citation_author=EK Schneider, B Huang, Z Zhu, DG DeWitt, JL Kinter, BP Kirtman, J Shukla; citation_volume=127; citation_publication_date=1999; citation_pages=1187-1207; citation_doi=10.1175/1520-0493(1999)127<1187:ODAIAP>2.0.CO;2; citation_id=CR35
citation_journal_title=J Clim; citation_title=Improvements to NOAA’s historical merged land–ocean surface temperature analysis (1880–2006); citation_author=TM Smith, RW Reynolds, TC Peterson, J Lawrimore; citation_volume=21; citation_publication_date=2008; citation_pages=2283-2296; citation_doi=10.1175/2007JCLI2100.1; citation_id=CR36
citation_journal_title=J Geophys Res; citation_title=Development of a four-dimensional variational coupled data assimilation system for enhanced analysis and prediction of seasonal to interannual climate variations; citation_author=N Sugiura, T Awaji, S Masuda, T Mochizuki, T Toyoda, T Miyama, H Igarashi, Y Ishikawa; citation_volume=113; citation_publication_date=2008; citation_pages=C10017; citation_doi=10.1029/2008JC004741; citation_id=CR37
citation_journal_title=J Clim; citation_title=Seasonal and interannual variability in a hybrid coupled GCM; citation_author=HH Syu, JD Neelin, D Gutzler; citation_volume=8; citation_publication_date=1995; citation_pages=2121-2143; citation_doi=10.1175/1520-0442(1995)008<2121:SAIVIA>2.0.CO;2; citation_id=CR38
citation_journal_title=J Clim; citation_title=Quantifying the dependence of westerly wind bursts on the large-scale tropical Pacific SST; citation_author=E Tziperman, L Yu; citation_volume=20; citation_publication_date=2007; citation_pages=2760-2768; citation_doi=10.1175/JCLI4138a.1; citation_id=CR39
citation_journal_title=Mon Wea Rev; citation_title=The BMRC coupled general circulation model ENSO forecast system; citation_author=G Wang, R Kleeman, N Smith, F Tseitkin; citation_volume=130; citation_publication_date=2002; citation_pages=975-991; citation_doi=10.1175/1520-0493(2002)130<0975:TBCGCM>2.0.CO;2; citation_id=CR40
citation_journal_title=J Geophys Res; citation_title=Water displacements in the Pacific and the genesis of El-Niño cycles; citation_author=K Wyrtki; citation_volume=90; citation_publication_date=1985; citation_pages=7129-7132; citation_doi=10.1029/JC090iC04p07129; citation_id=CR41
citation_journal_title=Mon Wea Rev; citation_title=A model El Niño Southern Oscillation; citation_author=SE Zebiak, MA Cane; citation_volume=115; citation_publication_date=1987; citation_pages=2262-2278; citation_doi=10.1175/1520-0493(1987)115<2262:AMENO>2.0.CO;2; citation_id=CR42
citation_journal_title=J Clim; citation_title=SST anomalies of ENSO and the Madden–Julian Oscillation in the equatorial Pacific; citation_author=Q Zhang, J Gottschalk; citation_volume=15; citation_publication_date=2002; citation_pages=2429-2445; citation_doi=10.1175/1520-0442(2002)015<2429:SAOEAT>2.0.CO;2; citation_id=CR43
citation_journal_title=Geophys Res Lett; citation_title=A new intermediate coupled model for El Niño simulation and prediction; citation_author=RH Zhang, SE Zebiak, R Kleeman, N Keenlyside; citation_volume=30; citation_publication_date=2003; citation_pages=2012; citation_doi=10.1029/2003GL018010; citation_id=CR44
citation_journal_title=Mon Wea Rev; citation_title=Retrospective El Niño forecast using an improved intermediate coupled model; citation_author=RH Zhang, SE Zebiak, R Kleeman, N Keenlyside; citation_volume=133; citation_publication_date=2005; citation_pages=2777-2802; citation_doi=10.1175/MWR3000.1; citation_id=CR45
citation_journal_title=Mon Wea Rev; citation_title=System design and evaluation of coupled ensemble data assimilation for global oceanic climate studies; citation_author=S Zhang, MJ Harrison, A Rosati, A Wittenberg; citation_volume=135; citation_publication_date=2007; citation_pages=3541-3564; citation_doi=10.1175/MWR3466.1; citation_id=CR46
citation_journal_title=J Geophys Res; citation_title=Balanced multivariate model errors of an intermediate coupled model for ensemble Kalman filter data assimilation; citation_author=F Zheng, J Zhu; citation_volume=113; citation_publication_date=2008; citation_pages=C07002; citation_doi=10.1029/2007JC004621; citation_id=CR47
citation_journal_title=Geophys Res Lett; citation_title=Ensemble hindcasts of SST anomalies in the tropical Pacific using an intermediate coupled model; citation_author=F Zheng, J Zhu, RH Zhang, GQ Zhou; citation_volume=33; citation_publication_date=2006; citation_pages=L19604; citation_doi=10.1029/2006GL026994; citation_id=CR48
citation_journal_title=Geophys Res Lett; citation_title=Impact of altimetry data on ENSO ensemble initializations and predictions; citation_author=F Zheng, J Zhu, RH Zhang; citation_volume=34; citation_publication_date=2007; citation_pages=L13611; citation_doi=10.1029/2007GL030451; citation_id=CR49
citation_journal_title=Adv Atmos Sci; citation_title=Ensemble hindcasts of ENSO events over past 120 years using large number of ensembles; citation_author=F Zheng, J Zhu, H Wang, RH Zhang; citation_volume=26; citation_publication_date=2009; citation_pages=100-113; citation_id=CR50
citation_journal_title=Clim Dyn; citation_title=The impact of nonlinear atmosphere on the fastest error growth of ENSO prediction; citation_author=X Zhou, Y Tang, Z Deng; citation_volume=30; citation_publication_date=2008; citation_pages=519-531; citation_doi=10.1007/s00382-007-0302-5; citation_id=CR51