Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203 * 1) 1) 2) 2) 1) (, 100081 ) 2) (, 730000 ) ( 2012 1 12 ; 2012 3 14 ).,, (PBEP).,, ;,.,,,,. :,,, PACS: 92.60.Wc, 92.60.Bh 1,,, [1 3]. [4 6].,., [7] [8] [9],,, [10] [11,12] [13]., [14,15], [16]..,,,, ( 2 ), ( Rossby ),,, ( ).,,,,.,, [17,18].,,.,, * (: 41105070, 40930952, 41005041) (: 2009BAC51B04) ( : GYHY201106016). E-mail: zhengzh@cma.gov.cn c 2012 Chinese Physical Society http://wulixb.iphy.ac.cn 199203-1
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203.,,,,,,, ;,,,,,,..,,,. 2 ϕ T = M(ϕ 0 ), (1) M, ϕ 0, ϕ T T. ϕ 0, M,.,, T.,,,,,, ;,,,,, [19]., [15,16],, (EOF),,,,, ψ, ϑ, ϕ = ψ + ϑ.,,,.,, [17,18].,. : ψ T = M s (ψ 0 ), ψ 0 R n t 0, ψ T R n T, M s. M s ( H s ), ( E) M s H s, E(ψ 0 ) = H s (ψ 0 ) M s (ψ 0 ). (2) - [20 22], : ψ 0, ψ 0 = ψ i + ψ i, ψ i ψ 0. ψ i (2), E( ψ i ) = H s ( ψ i ) M s ( ψ i ), (3), H s ( ψ i ) i,,, M s ( ψ i ),,., E( ψ i ). ψ 0 ψ i, E( ψ i ) ψ 0 Taylor, ψ i E( ψ i ) = E(ψ 0 ψ i) E(ψ 0 ) ψ i E, (4) ψ ψ=ψ0 k, E( ψ i ) E(ψ 0 ),,,,. i ψ T i = M s (ψ 0 ) + E( ψ i ), (5) 199203-2
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203, M s (ψ 0 ) T, E( ψ i ),,.,. 6 h,, 6 h 6 h,, 6 h (,, 6 h 6 h,, 6 h, 5 ),,,.,.,,.,,,.,,. ϑ T i = ϑ T i, (6), ϑ T i i T.,, i ϕ T i = ψ T i + ϑ T i = M s (ψ 0 ) + E( ψ i ) + ϑ T i, (7), M s (ψ 0 ) T, E( ψ i ), ; ϑ T i i T,.,,, ;,,,, ;,,,. 3, 6 15, : 1) (EPS). 2) EPS,,,,.,, 4. 3) 40, 40,, 6 h,,. 4) 40. T63L16 (EPS),,,,.,., 2004 2008 1 16 12 5, 500 hpa,,. 199203-3
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203 (90 N 90 S, 0 E 360 E), (20 N 90 N, 0 E 360 E), (20 S 90 S, 0 E 360 E) (20 N 20 S, 0 E 360 E)4. 1 5 500 hpa (ACC),,, (PBEP) ACC EPS. T63 EPS,,, 6 ACC 0.4,, PBEP 6 ACC 0.6,,. EPS PBEP,., PBEP ACC. ACC, PBEP, 6 8, 13, 13 ; ;, ;, 6 8,,,,. 1 5 500 hpa ACC (a) ; (b) ; (c) ; (d) 2 5 500 hpa (RMSE),, PBEP RMSE EPS,. ACC, PBEP 3, 6 8 RMSE, 8 13, 13. EPS 6,, PBEP EPS., ACC RMSE, PBEP,., 3 4 500 hpa ACC RMSE,, PBEP EPS,, 2 3 ACC 0.15 0.13, RMSE 13.52 gpm 12.28 gpm; 6 15 ACC 0.12, RMSE 12.36 gpm., PBEP, 6 15 ACC, 0.28,, 0.17, 199203-4
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203 0.07; RMSE 18.50 gpm, 9.46 gpm. ACC RMSE, 2 3. 2 5 500 hpa RMSE (a) ; (b) ; (c) ; (d) 3 500 hpa ACC (a) ; (b) ; (c) ; (d),, 1 500 hpa ACC RMSE,,,PBEP EPS.PBEP EPS 0, 1 3 4 9 ACC 0.20, 0.09 0.12, RMSE 199203-5
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203 17.20 gpm, 3.88 gpm 2.08 gpm, 0,., 0 ACC, 0.62,, 0.28,, 0.04,, ACC ; 0 RMSE, 29.60 gpm,, 11.24 gpm, 5.42 gpm,, 0. 4 500hPa RMSE (a) ; (b) ; (c) ; (d) 1 500 hpa ACC RMSE ACC RMSE/gpm 0 1 3 4 9 0 1 3 4 9 NHE SHE TRO EPS 0.42 0.38 0.36 37.94 42.60 29.72 PBEP 0.62 0.47 0.47 20.74 38.72 27.60 EPS 0.25 0.49 0.52 59.04 56.02 35.42 PBEP 0.53 0.53 0.48 29.44 54.08 33.34 EPS 0.47 0.09 0.04 23.74 46.06 36.54 PBEP 0.51 0.28 0.23 18.32 38.26 33.72 EPS 0.15 0.09 0.16 15.48 10.84 5.50 PBEP 0.47 0.33 0.46 4.24 8.20 4.58 4,, 5 PBEP EPS MSSS, MSSS PBEP EPS, [, 1], MSSS, PBEP EPS, MSSS 0.,,,, 0.8., 60 N, 199203-6
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203, [23],.,., PBEP EPS. 5 PBEP EPS 500 hpa MSSS, PBEP 6 15, EPS.,, ACC, RMSE., 0., PBEP,,.,,,,. 4,,.,., ;,,,,., 6 15,,,,., ;,,.,,,. [1] Lorenz E N 1963 J. Atmos. Sci. 20 130 [2] Chou J F 1989 Adv. Atmos. Sci. 6 335 [3] Chen B H, Li J P, Ding R Q 2006 Science in China (Series D) 49 1111 [4] Buizza R, Houtekamer, P L, Toth Z, Pellerin G, Wei M, Zhu Y 2005 Mon. Wea. Rev. 133 1076 [5] Zhu Y 2005 Adv. Atmos. Sci. 22 781 [6] Feng G L, Dong W J 2003 Acta Phys. Sin. 52 2347 (in Chinese) [, 2003 52 2347] [7] Toth Z, Kalnay E 1997 Mon. Wea. Rev. 125 3297 [8] Molteni F, Buizza R, Palmer T N, Petroliagis T 1996 Quart. J. Roy. Meteor. Soc 122 73 [9] Houtekamer, P L, Lefaivre L, Derome J, Ritchie H, Mitchell H L 1996 Mon. Wea. Rev. 124 1225 [10] Gong J D, Li W J, Chou J F 1999 Chinese Science Bulletin 44 1113 (in Chinese) [,, 1999 44 1113] [11] Mu M, Jiang Z N 2007 Chinese Science Bulletin 52 1457 (in Chinese) [, 2007 52 1457] [12] Duan W S, Mu M 2009 Science in China (Series D) 52 884 [13] Wei M, Toth Z, Wobus R, Zhu Y, Bishop C H, Wang X 2006 Tellus 58 28 [14] Buizza R, Miller M, Palmer T N 1999 Quart. J. Roy. Meteor. Soc. 125 2887 [15] Mu M, Duan W S, Wang Q, Zhang R 2010 Nonlinear Processes in Geophysics 17 211 [16] Krishnamurti T N, Kishtawal C M, Zhang Z, Larow T, Bachiochi D, Williford E, Gadgil S, Surendran S 2000 J. Climate 13 4196 199203-7
Acta Phys. Sin. Vol. 61, No. 19 (2012) 199203 [17] Zheng Z H 2010 Ph. D. Dissertation (Lanzhou: Lanzhou University) (in Chinese) [ 2010 ( : )] [18] Chou J F, Zheng Z H, Sun S P 2010 Scientia Meteorologica Sinica 30 569(in Chinese) [,, 2010 30 569] [19] Wang P, Dai X G 2005 Acta Phys. Sin. 54 4961 (in Chinese) [, 2005 54 4961] [20] Huang J P, Yi Y H, Wang S W, Chou J F 1993 Quart. J. Roy. Meteor. Soc. 119 547 [21] Gao L, Ren H L, Li J P, Chou J F 2006 Chin. Phys. 15 882 [22] Zheng Z H, Feng G L, Chou J F, Ren H L 2010 Journal of Applied Meteorological Science 21 139 (in Chinese) [,,, 2010 21 139] [23] Shi N, Chen H, Chen Y, 2001 Journal of Tropical Meteorology 17 215 (in Chinese) [,, 2001 17 215] Predictability-based extended-range ensemble prediction method and numerical experiments Zheng Zhi-Hai 1) Feng Guo-Lin 1) Huang Jian-Ping 2) Chou Ji-Fan 2) 1) ( National Climate Center, China Meterological Administration, Beijing 100081, China ) 2) ( College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China ) ( Received 12 January 2012; revised manuscript received 14 March 2012 ) Abstract Ensemble prediction is an effective approach to accounting for uncertainties of initial conditions and model error. By combining the predictability of extended-range, both predictable components and unpredictable random components with different characteristics are treated with different ensemble prediction schemes and strategies. A new predictability-based extended-range ensemble prediction method (PBEP) is proposed. In this method, for predictable component, the uncertainty of model is taken into account through the use of multiple error correction scheme; while the random component probability distribution is obtained from the climate probability distribution of historical data, for the sake of avoiding the influence of model error. Prediction results show that the ensemble prediction method can improve the forecast skill in all regions of the world, and the extents of improvement are different for waves with different spatial scales compared with the operational dynamical extended-range ensemble prediction system of NCC/CMA, exhibiting its potential application perspective to operational extended-range prediction. Keywords: extended-range forecast, predictability, ensemble prediction, predictable components PACS: 92.60.Wc, 92.60.Bh * Project supported by the National Natural Science Foundation of China (Grant Nos. 41105070, 40930952, 41005041), the State Key Program of Science and Technology of China (Grant No. 2009BAC51B04), and the Meteorological Special Project of China (Grant No. GYHY201106016). E-mail: zhengzh@cma.gov.cn 199203-8