PACS: Wc, Bh

Transcription

1 Acta Phys. Sin. Vol. 61, No. 19 (2012) * 1) 1) 2) 2) 1) (, ) 2) (, ) ( ; ).,, (PBEP).,, ;,.,,,,. :,,, PACS: Wc, Bh 1,,, [1 3]. [4 6].,., [7] [8] [9],,, [10] [11,12] [13]., [14,15], [16]..,,,, ( 2 ), ( Rossby ),,, ( ).,,,,.,, [17,18].,,.,, * (: , , ) (: 2009BAC51B04) ( : GYHY ). zhengzh@cma.gov.cn c 2012 Chinese Physical Society

2 Acta Phys. Sin. Vol. 61, No. 19 (2012) ,,,,,,, ;,,,,,,..,,,. 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)

3 Acta Phys. Sin. Vol. 61, No. 19 (2012) , 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),,,,.,., , 500 hpa,,

4 Acta Phys. Sin. Vol. 61, No. 19 (2012) (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) 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,,,, hpa ACC (a) ; (b) ; (c) ; (d) hpa (RMSE),, PBEP RMSE EPS,. ACC, PBEP 3, 6 8 RMSE, 8 13, 13. EPS 6,, PBEP EPS., ACC RMSE, PBEP,., hpa ACC RMSE,, PBEP EPS,, 2 3 ACC , RMSE gpm gpm; 6 15 ACC 0.12, RMSE gpm., PBEP, 6 15 ACC, 0.28,, 0.17,

5 Acta Phys. Sin. Vol. 61, No. 19 (2012) ; RMSE gpm, 9.46 gpm. ACC RMSE, hpa RMSE (a) ; (b) ; (c) ; (d) hpa ACC (a) ; (b) ; (c) ; (d),, hpa ACC RMSE,,,PBEP EPS.PBEP EPS 0, ACC 0.20, , RMSE

6 Acta Phys. Sin. Vol. 61, No. 19 (2012) gpm, 3.88 gpm 2.08 gpm, 0,., 0 ACC, 0.62,, 0.28,, 0.04,, ACC ; 0 RMSE, gpm,, gpm, 5.42 gpm,, hPa RMSE (a) ; (b) ; (c) ; (d) hpa ACC RMSE ACC RMSE/gpm NHE SHE TRO EPS PBEP EPS PBEP EPS PBEP EPS PBEP ,, 5 PBEP EPS MSSS, MSSS PBEP EPS, [, 1], MSSS, PBEP EPS, MSSS 0.,,,, 0.8., 60 N,

7 Acta Phys. Sin. Vol. 61, No. 19 (2012) , [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 [2] Chou J F 1989 Adv. Atmos. Sci [3] Chen B H, Li J P, Ding R Q 2006 Science in China (Series D) [4] Buizza R, Houtekamer, P L, Toth Z, Pellerin G, Wei M, Zhu Y 2005 Mon. Wea. Rev [5] Zhu Y 2005 Adv. Atmos. Sci [6] Feng G L, Dong W J 2003 Acta Phys. Sin (in Chinese) [, ] [7] Toth Z, Kalnay E 1997 Mon. Wea. Rev [8] Molteni F, Buizza R, Palmer T N, Petroliagis T 1996 Quart. J. Roy. Meteor. Soc [9] Houtekamer, P L, Lefaivre L, Derome J, Ritchie H, Mitchell H L 1996 Mon. Wea. Rev [10] Gong J D, Li W J, Chou J F 1999 Chinese Science Bulletin (in Chinese) [,, ] [11] Mu M, Jiang Z N 2007 Chinese Science Bulletin (in Chinese) [, ] [12] Duan W S, Mu M 2009 Science in China (Series D) [13] Wei M, Toth Z, Wobus R, Zhu Y, Bishop C H, Wang X 2006 Tellus [14] Buizza R, Miller M, Palmer T N 1999 Quart. J. Roy. Meteor. Soc [15] Mu M, Duan W S, Wang Q, Zhang R 2010 Nonlinear Processes in Geophysics [16] Krishnamurti T N, Kishtawal C M, Zhang Z, Larow T, Bachiochi D, Williford E, Gadgil S, Surendran S 2000 J. Climate

8 Acta Phys. Sin. Vol. 61, No. 19 (2012) [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 (in Chinese) [,, ] [19] Wang P, Dai X G 2005 Acta Phys. Sin (in Chinese) [, ] [20] Huang J P, Yi Y H, Wang S W, Chou J F 1993 Quart. J. Roy. Meteor. Soc [21] Gao L, Ren H L, Li J P, Chou J F 2006 Chin. Phys [22] Zheng Z H, Feng G L, Chou J F, Ren H L 2010 Journal of Applied Meteorological Science (in Chinese) [,,, ] [23] Shi N, Chen H, Chen Y, 2001 Journal of Tropical Meteorology (in Chinese) [,, ] 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 , China ) 2) ( College of Atmospheric Sciences, Lanzhou University, Lanzhou , 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: Wc, Bh * Project supported by the National Natural Science Foundation of China (Grant Nos , , ), the State Key Program of Science and Technology of China (Grant No. 2009BAC51B04), and the Meteorological Special Project of China (Grant No. GYHY ). zhengzh@cma.gov.cn