Testing a four-dimensional variational data assimilation method using an improved intermediate coupled model for ENSO analysis and prediction
- 291 Downloads
- 5 Citations
Abstract
A four-dimensional variational (4D-Var) data assimilation method is implemented in an improved intermediate coupled model (ICM) of the tropical Pacific. A twin experiment is designed to evaluate the impact of the 4D-Var data assimilation algorithm on ENSO analysis and prediction based on the ICM. The model error is assumed to arise only from the parameter uncertainty. The “observation” of the SST anomaly, which is sampled from a “truth” model simulation that takes default parameter values and has Gaussian noise added, is directly assimilated into the assimilation model with its parameters set erroneously. Results show that 4D-Var effectively reduces the error of ENSO analysis and therefore improves the prediction skill of ENSO events compared with the non-assimilation case. These results provide a promising way for the ICM to achieve better real-time ENSO prediction.
Key words
Four-dimensional variational data assimilation intermediate coupled model twin experiment ENSO predictionReferences
- Balmaseda, M. A., D. L. T. Anderson, and M. K. Davey, 1994: ENSO prediction using a dynamical ocean model coupled to statistical atmospheres. Tellus A, 46(4), 497–511.CrossRefGoogle Scholar
- Barnett, T. P., N. Graham, S. Pazan, W. White, M. Latif, and M. Flügel, 1993: ENSO and ENSO-related predictability. Part I: Prediction of equatorial Pacific sea surface temperature with a hybrid coupled ocean–atmosphere model. J. Climate, 6, 1545–1566.CrossRefGoogle Scholar
- Bjerknes, J., 1969: Atmospheric teleconnections from the equatorial Pacific. Mon. Wea. Rev., 97, 163–172.CrossRefGoogle Scholar
- Cane, M. A., S. E. Zebiak, and S. C. Dolan, 1986: Experimental forecasts of El Niño. Nature, 321(6073), 827–832.CrossRefGoogle Scholar
- Chen, D., S. E. Zebiak, A. J. Busalacchi, and Cane, M. A., 1995: An improved procedure for El Niñoforecasting: Implications for predictability. Science, 269, 1699–1702.CrossRefGoogle Scholar
- Derber, J., and A. Rosati, 1989: A global oceanic data assimilation system. J. Phys. Oceanogr., 19(9), 1333–1347.CrossRefGoogle Scholar
- Dommenget, D., and D. Stammer, 2004: Assessing ENSO simulations and predictions using adjoint ocean state estimation. J. Climate, 17(22), 4301–4315.CrossRefGoogle Scholar
- Evensen, G., 1994: Sequential data assimilation with a nonlinear quasi-geostrophic model using Monte Carlo methods toforecast error statistics. J. Geophys. Res., 99, 10143–10162.CrossRefGoogle Scholar
- Galanti, E., E. Tziperman, M. Harrison, A. Rosati, and Z. Sirkes, 2003: A study of ENSO prediction using a hybrid coupled model and the adjoint method for data assimilation. Mon. Wea. Rev., 131(11), 2748–2764.CrossRefGoogle Scholar
- Han, G. J., W. Li, Z. J. He, K. X. Liu, and J. R. Ma, 2006: Assimilated tidal results of tide gauge and TOPEX/POSEIDON data over the China seas using a variational adjoint approach with a nonlinear numerical model. Adv. Atmos. Sci., 23, 449–460, doi: 10.1007/s00376-006-0449-8.CrossRefGoogle Scholar
- Han, G. J., X. R. Wu, S. Q. Zhang, Z. Y. Liu, I. M. Navon, and W. Li, 2015: A study of coupling parameter estimation implemented by 4D-Var and EnKF with a simple coupled system. Advances in Meteorology, 2015, doi: 10.1155/2015/530764.Google Scholar
- Houtekamer, P. L., and H. L. Mitchell, 1998: Data assimilation using an ensemble Kalman filter technique. Mon. Wea. Rev., 126(3), 796–811.CrossRefGoogle Scholar
- Kalnay, E., 2003: Atmospheric Modeling, Data Assimilation and Predictability. Cambridge University Press, 342pp.Google Scholar
- Keenlyside, N., and R. Kleeman, 2002: Annual cycle of equatorial zonal currents in the Pacific. J. Geophys. Res., 107(C8), 8–1.CrossRefGoogle Scholar
- Keenlyside, N., M. Latif, M. Botzet, J. Jungclaus, and U. Schulzweida, 2005: A coupled method for initializing El Niño Southern Oscillation forecasts using sea surface temperature. Tellus A, 57(3), 340–356.CrossRefGoogle Scholar
- Kirtman, B. P., and S. E. Zebiak, 1997: ENSO simulation and prediction with a hybrid coupled model. Mon. Wea. Rev., 125(10), 2620–2641.CrossRefGoogle Scholar
- Kleeman, R., A. M. Moore, and N. R. Smith, 1995: Assimilation of subsurface thermal data into a simple ocean model for the initialization of an intermediate tropical coupled ocean–atmosphere forecast model. Mon.Wea. Rev., 123, 3103–3114.CrossRefGoogle Scholar
- Klinker, E., F. Rabier, G. Kelly, and J. F. Mahfouf, 2000: The ECMWF operational implementation of four-dimensional variational assimilation. III: experimental results and diagnostics with operational configuration. Quart. J. Roy. Meteor. Soc., 126, 1191–1215.CrossRefGoogle Scholar
- Kumar, A., H. Wang, Y. Xue, and W. Q. Wang, 2014: How much of monthly subsurface temperature variability in the equatorial Pacific can be recovered by the specification of sea surface temperatures?. J. Climate, 27, 1559–1577.CrossRefGoogle Scholar
- Liu, D. C., and J. Nocedal, 1989: On the limited memory BFGS method for large scale optimization. Mathematical Programming, 45, 503–528.CrossRefGoogle Scholar
- McCreary, J. P., 1981: A linear stratified ocean model of the equatorial undercurrent. Philos. Trans. Roy. Soc. London, 298, 603–635.CrossRefGoogle Scholar
- McCreary, J. P., Jr., 1983: A model of tropical ocean-atmosphere interaction. Mon. Wea. Rev., 111(2), 370–387.CrossRefGoogle Scholar
- Mu, M., W.-S. Duan, D. Chen, and W. D. Yu. 2015: Target observations for improving initialization of high-impact oceanatmospheric environmental events forecasting. National Science Review, 2, 226–236.CrossRefGoogle Scholar
- Navon, I. M., X. Zou, J. Derber, and J. Sela, 1992: Variational data assimilation with an adiabatic version of the NMC spectral model. Mon. Wea. Rev., 120, 1433–1446.CrossRefGoogle Scholar
- Neelin, J. D., 1990: A hybrid coupled general circulation model for El Niño studies. J. Atmos. Sci., 47(5), 674–693.CrossRefGoogle Scholar
- Peng, S. Q., and L. Xie, 2006: Effect of determining initial conditions by four-dimensional variational data assimilation on storm surge forecasting. Ocean Modelling, 14(1), 1–18.CrossRefGoogle Scholar
- Philander, S. G. H., R. C. Pacanowski, N. C. Lau, and M. J. Nath, 1992: Simulation of ENSO with a global atmospheric GCM coupled to a high-resolution tropical Pacific Ocean GCM. J. Climate, 5(4), 308–329.CrossRefGoogle Scholar
- Reynolds, R. W., N. A. Rayner, T. M. Smith, D. C. Stokes, and W. Wang, 2002: An improved in situ and satellite SST analysis for climate. J. Climate, 15(13), 1609–1625.CrossRefGoogle Scholar
- Rosati, A., K. Miyakoda, and R. Gudgel, 1997: The impact of ocean initial conditions on ENSO forecasting with a coupled model, Mon. Wea. Rev., 125(5), 754–772.CrossRefGoogle Scholar
- Sugiura, N., T. Awaji, S. Masuda, T. Mochizuki, T. Toyoda, T. Miyama, H. Igarashi, and Y. Ishikawa, 2008: Development of a four-dimensional variational coupled data assimilation system for enhanced analysis and prediction of seasonal to interannual climate variations. J. Geophys. Res., 113(C10), C10017.CrossRefGoogle Scholar
- Tang, Y. M., and W. W. Hsieh, 2001: Coupling neural networks to incomplete dynamical systems via variational data assimilation. Mon. Wea. Rev., 129(4), 818–834.CrossRefGoogle Scholar
- Tang, Y. M., J. Ambandan, and D. K. Chen, 2014: Nonlinear measurement function in the ensemble Kalman filter. Adv Atmos. Sci., 31(3), 551–558, doi: 10.1007/s00376-013-3117-9.CrossRefGoogle Scholar
- Wang, B., X. L. Zou, and J. Zhu, 2000: Data assimilation and its applications. Proceedings of the National Academy of Sciences of the United States of America, 97(21), 11143–11144.CrossRefGoogle Scholar
- Weaver, A. T., J. Vialard, and D. L. T. Anderson, 2003: Three and four dimensional variational assimilation with a general circulation model of the tropical Pacific Ocean: Part I: formulation, internal diagnostics, and consistency checks. Mon. Wea. Rev., 131, 1360–1378.CrossRefGoogle Scholar
- Wu, X. R., S. Q. Zhang, Z. Y. Liu, A. Rosati, T. L. Delworth, and Y. Liu, 2012: Impact of geographic-dependent parameter optimization on climate estimation and prediction: Simulation with an intermediate coupled model. Mon. Wea. Rev., 140(12), 3956–3971.CrossRefGoogle Scholar
- Wu, X. R., W. Li, G. J. Han, S. Q. Zhang, and X. D. Wang, 2014: A compensatory approach of the fixed localization in EnKF. Mon. Wea. Rev., 142, 3713–3733.CrossRefGoogle Scholar
- Wu, X. R., G. J. Han, S. Q. Zhang, and Z. Y. Liu, 2016: A study of the impact of parameter optimization on ENSO predictability with an intermediate coupled model. Climate Dyn., 46, 711–727, doi: 10.1007/s00382-015-2608-z.CrossRefGoogle Scholar
- Wyrtki, K., 1975: El Niño-the dynamic response of the equatorial Pacific Ocean to atmospheric forcing. J. Phys. Oceanogr., 5(4), 572–584.CrossRefGoogle Scholar
- Zebiak, S. E., and M. A. Cane, 1987: A model El Niño-Southern oscillation. Mon. Wea. Rev., 115, 2262–2278.CrossRefGoogle Scholar
- Zhang, R. H., and C. Gao, 2015: Role of subsurface entrainment temperature (Te) in the onset of El Niño events, as represented in an intermediate coupled model. Climate Dyn., 1–19, doi: 10.1007/s00382-015-2655-5.Google Scholar
- Zhang, R. H., S. E. Zebiak, R. Kleeman, and N. Keenlyside, 2003: A new intermediate coupled model for El Niño simulation and prediction. Geophys. Res. Lett., 30(19), doi:10.1029/2003GL018010,19.Google Scholar
- Zhang, R. H., R. Kleeman, S. E. Zebiak, N. Keenlyside, and S. Raynaud, 2005a: An empirical parameterization of subsurface entrainment temperature for improved SST anomaly simulations in an intermediate ocean model. J. Climate, 18, 350–371.CrossRefGoogle Scholar
- Zhang, R. H., S. E. Zebiak, R. Kleeman, and N. Keenlyside, 2005b: Retrospective El Niñoforecasts using an improved intermediate coupled model. Mon. Wea. Rev., 133, 2777–2802.CrossRefGoogle Scholar
- Zhang, R. H., A. J. Busalacchi, and D. G. DeWitt, 2008: The roles of atmospheric stochastic forcing (SF) and oceanic entrainment temperature (Te) in decadal modulation of ENSO. J. Climate, 21, 674–704.CrossRefGoogle Scholar
- Zhang, R. H., F. Zheng, J. Zhu, and Z. G. Wang, 2013: A successful real-time forecast of the 2010–11 La Niña event. Sci. Rep., 3, 1108, doi: 10.1038/srep01108.Google Scholar
- Zhang, R. H., C. Gao, X. B. Kang, H. Zhi, Z. G. Wang, and L. C. Feng, 2015: ENSO modulations due to interannual variability of freshwater forcing and ocean biology-induced heating in the tropical Pacific. Sci. Rep., 5, 18506, doi: 10.1038/srep18506.CrossRefGoogle Scholar
- Zhang, S., X. Zou, and J. E. Ahlquist, 2001: Examination of numerical results from tangent linear and adjoint of discontinuous nonlinear models. Mon. Wea. Rev., 129(11), 2791–2804.CrossRefGoogle Scholar
- Zhang, S., M. J. Harrison, A. T. Wittenberg, A. Rosati, J. L. Anderson, and V. Balaji, 2005c: Initialization of an ENSO forecast system using a parallelized ensemble filter. Mon. Wea. Rev., 133(11), 3176–3201.CrossRefGoogle Scholar
- Zhang, S., M. J. Harrison, A. Rosati, and A. Wittenberg, 2007: System design and evaluation of coupled ensemble data assimilation for global oceanic climate studies. Mon. Wea. Rev., 135(10), 3541–3564.CrossRefGoogle Scholar
- Zhang, S., Y. S. Chang, X. Yang, and A. Rosati, 2014: Balanced and coherent climate estimation by combining data with a biased coupled model. J. Climate, 27(3), 1302–1314.CrossRefGoogle Scholar
- Zhang, X. F., S. Q. Zhang, Z. Y. Liu, X. R. Wu, and G. J. Han, 2015a: Parameter optimization in an intermediate coupled climate model with biased physics. J. Climate, 28(3), 1227–1247.CrossRefGoogle Scholar
- Zhang, X. F., G. J. Han, D. Li, X. R. Wu, W. Li, and P. C. Chu, 2015b: Variational estimation of wave-affected parameters in a two-equation turbulence model. J. Atmos. Oceanic Technol., 32(3), 528–546.CrossRefGoogle Scholar
- Zheng, F., J. Zhu, R. H. Zhang, and G. Q. Zhou, 2006: Ensemble hindcasts of SST anomalies in the tropical Pacific using an intermediate coupled model. Geophys. Res. Lett., 33(19), L19604.CrossRefGoogle Scholar
- Zheng, F., J. Zhu, H. Wang, and R. H. Zhang, 2009: Ensemble hindcasts of ENSO events over the past 120 years using a large number of ensembles. Adv. Atmos. Sci., 26, 359–372, doi: 10.1007/s00376-009-0359-7.CrossRefGoogle Scholar
- Zhu, J., G. Q. Zhou, C. X. Yan, W. W. Fu, and X. B. You, 2006: A three-dimensional variational ocean data assimilation system: scheme and preliminary results. Science in China Series D: Earth Sciences, 49(11), 1212–1222.CrossRefGoogle Scholar
- Zhu, J. S., A. Kumar, H. Wang, and B. H. Huang, 2015: Sea surface temperature predictions in NCEP CFSv2 using a simple ocean initialization scheme. Mon. Wea. Rev., 143, 3176–3191.CrossRefGoogle Scholar
- Zou, X., I. M. Navon, M. Berger, K. H. Phua, T. Schlick, and F. X. Le Dimet, 1993: Numerical experience with limited-memory quasi-Newton and truncated Newton methods. SIAM Journal on Optimization, 3(3), 582–608.CrossRefGoogle Scholar