南海夏季风爆发的数值模拟
Simulation of the South China Sea Summer Monsoon Onset
-
摘要: 利用高分辨率的区域气候模式 (RegCM_NCC) 对南海夏季风爆发进行模拟研究。研究表明:该模式对积云对流参数化方案的选择十分敏感, 其中以Kuo积云参数化方案为最好, 可以比较成功地模拟出南海夏季风的爆发时间、爆发前后高、低层风场的剧烈变化以及季风与季风雨带的向北推进。然而该方案对于雨量和副热带高压位置的模拟, 与观测相比尚存在一定的偏差, 主要表现为副热带高压位置模拟偏北、偏东; 南海地区的降水量模拟偏少、降水范围偏小。此外, 采用4种参数化方案 (Kuo, Grell, MFS, Betts-Miller) 集成的结果在某种程度上要优于单个方案的结果, 这种改善主要体现在对南海地区季风爆发后降水的模拟上。Abstract: Generally speaking, the South China Sea summer monsoon (SCSSM) onset marks the arrival of the East and Southeast Asian summer monsoon and the beginning of the major rainy season in these regions. Therefore, the correct simulation of SCSSM has a significant implication. General Circulation Models (GCMs) have limitations in reproducing regional details because of the relatively low spatial resolution and simple representation of physical processes. Hence many studies tends to use air-sea coupled model and regional climate model to simulate the seasonal variations and anomalies of the East Asian monsoon.As an important energy source for atmospheric motion, cumulus convection plays a key role in determining the structure of temperature and moisture in the atmosphere. With the development of numerical model, different cumulus parameterization schemes have been designed and applied in the numerical weather forecasting models and the simulations of atmospheric general circulation. Many studies show that the choices of different cumulus parameterization schemes may have significant influences on the simulations of synoptic and climate systems, therefore the choice of the cumulus parameterization scheme has been one of the important problems in the modeling research. With the high-resolution regional climate model of China National Climate Center (RegCM_NCC), four cumulus parameterization schemes (Kuo, Grell, MFS, Betts-Miller) are adopted to carry out a series of sensitivity experiments on the SCSSM onset in 1998. The results indicate that the model is very sensitive to the choice of convective parameterization schemes. It seems that the Kuo cumulus scheme simulates the process of the SCSSM onset reasonably well, which can reproduce the onset timing and dramatic changes before and after the SCSSM onset, especially the upper and lower level flow patterns. For the amount of precipitation and location of the subtropical high, there are still some biases between the simulations and the observations, including the location of the subtropical high simulated further north and east, the precipitation amount over the South China Sea too little as well as the range of precipitation too narrow. The ensemble results are obviously superior to any single cumulus parameterization scheme and the obvious improvement is mainly on the simulation of precipitation over the South China Sea.
-
Key words:
- South China Sea summer monsoon;
- onset;
- numerical simulation
-
表 1 1998年5月南海地区观测与模拟的降水比较
表 2 1998年6月南海地区观测与模拟的降水比较
-
[1] 王启祎, 丁一汇, 江滢.亚洲季风活动及其与中国大陆降水关系.应用气象学报, 1998, 9(增刊):84-89. http://www.cnki.com.cn/Article/CJFDTOTAL-YYQX8S1.010.htm [2] Goswami B N.Interannual variations of Indian summer monsoon in a GCM:External conditions versus internal feedbacks. J Climate, 1998, 11:501-522. doi: 10.1175/1520-0442(1998)011<0501:IVOISM>2.0.CO;2 [3] Webster P J, Magana V O, Palmer T N, et al. Monsoons:process, predictability, and the prospects for forecast. J Geophys Res, 1998, 103:14451-14510. doi: 10.1029/97JC02719 [4] Kang I S Jin K, Lau K M, et al.Intercomparison of atmospheric GCM simulated anomalies associated with the 1997/98 El Niño. J Climate, 2002, 15:2791-2805. doi: 10.1175/1520-0442(2002)015<2791:IOAGSA>2.0.CO;2 [5] Kang I S, Jin K, Wang B.Intercomparison of the climatological variations of Asian summer monsoon precipitation simulated by 10 GCMs.Climate Dyn, 2002, 19:383-395. doi: 10.1007/s00382-002-0245-9 [6] Waliser D E, Stony Brook S, Jin K, et al.AGCM simulations of intraseasonal variability associated with the Asian summer monsoon. Climate Dyn, 2003, 21:423-446. doi: 10.1007/s00382-003-0337-1 [7] Sperber K R, Palmer T N. Interannual tropical rainfall variability in general circulation model simulations associated with the Atmospheric Model Inter-comparison Project.J Climate, 1996, 9:2727-2750. doi: 10.1175/1520-0442(1996)009<2727:ITRVIG>2.0.CO;2 [8] Gadgil S, Sajani S.Monsoon precipitation in the AMIP runs. Climate Dyn, 1998, 14:659-689. doi: 10.1007/s003820050248 [9] 罗勇, 赵宗慈.NCAR RegCM2对东亚区域气候的模拟试验.应用气象学报, 1997, 8(增刊):124-133. http://www.cnki.com.cn/Article/CJFDTOTAL-YYQX7S1.016.htm [10] 赵宗慈, 丁一汇, 李晓东, 等.海气耦合模式在东亚地区的可靠性评估.应用气象学报, 1995, 6(增刊):9-18. http://www.cnki.com.cn/Article/CJFDTOTAL-YYQX5S1.001.htm [11] 柳艳菊, 丁一汇, Keenan T, 等. POAMA海气耦合模式对2003和2004年南海夏季风报能力的评估.热带海洋学报, 2005, 24(5):19-30. http://www.cnki.com.cn/Article/CJFDTOTAL-RDHY200505002.htm [12] Liu Yiming, Ding Yihui.Simulation of activity of the Asian summer monsoon and heavy rainfalls in China in 1998 with region climate model.Acta Meteor Sinica, 2003, 17(Suppl):273-288. http://en.cnki.com.cn/Article_en/CJFDTOTAL-QXXW2003S1024.htm [13] 吴池盛, 冯瑞权, 古志明, 等.南海夏季风爆发的数值预报模拟实验.气候与环境研究, 2000, 5(4):486-494. http://www.cnki.com.cn/Article/CJFDTOTAL-QHYH200004013.htm [14] 钟中, 汤剑平. 1998年南海夏季风爆发过程数值模拟.解放军理工大学学报, 2002, 3(6):80-84. http://www.cnki.com.cn/Article/CJFDTOTAL-JFJL200206016.htm [15] Ren Xuejuan, Qian Yongfu.Development of a coupled regional air-sea model and its numerical simulation for summer monsoon in 1998. Acta Meteor Sinica, 2001, 15(4):385-396. http://mall.cnki.net/magazine/Article/QXXW200104000.htm [16] Chan J C L, Liu Yiming, Chow K C, et al. Design of a regional climate model for the simulation of South China summer monsoon rainfall. J Meteor Soc Japan, 2004, 82(6):1645-1665. doi: 10.2151/jmsj.82.1645 [17] Liu Yiming, Chan J C L, Chow K C, et al.Ten-year climatology of summer monsoon over south China and its surroundings simulated from a regional climate model. Int J Climatol, 2006, 26:141-157. doi: 10.1002/(ISSN)1097-0088 [18] Ding Yihui, Shi Xueli, Liu Yiming, et al. Multi-year simulations and experimental seasonal predictions for rainy seasons in China by using a nested regional climate model (RegCM_NCC).Part Ⅰ:sensitivity study.Adv Atmos Sci, 2006, 23(3):323-341. doi: 10.1007/s00376-006-0323-8 [19] Ding Yihui, Liu Yiming, Shi Xueli, et al.Multi-year simulations and experimental seasonal predictions for rainy seasons in China by using a nested regional climate model (RegCM_NCC). Part Ⅱ:the experimental seasonal prediction.Adv Atmos Sci, 2006, 23(4):487-503. doi: 10.1007/s00376-006-0487-2 [20] Giorgi F, Marinucci M R, Bates G T. Development of a second-generation regional climate model (RegCM2). Part Ⅰ:boundary-layer and radiative transfer processes.Mon Wea Rev, 1993, 121:2794-2813. doi: 10.1175/1520-0493(1993)121<2794:DOASGR>2.0.CO;2 [21] Giorgi F, Shields C. Tests of precipitation parameterizations available in the latest version of the NCAR regional climate model (RegCM2) over the continental United States.J Geophys Res, 1999, 104:6353-6375. doi: 10.1029/98JD01164 [22] 魏和林, 符淙斌, 王维强.区域气候模式侧边界的处理对东亚夏季风降水模拟的影响.大气科学, 1998, 22(5):779-790. http://www.cnki.com.cn/Article/CJFDTOTAL-DQXK805.012.htm [23] 潘劲松, 翟国庆, 高坤.区域气候模拟中多种对流参数化方案的比较研究.大气科学, 2002, 26(2):206-220. http://www.cnki.com.cn/Article/CJFDTOTAL-DQXK200202005.htm [24] Giorgi F, Marinucci M R, Bates G T, et al.Development of a second-generation regional climate model (RegCM2). Part Ⅱ:convective processes and assimilation of lateral boundary conditions.Mon Wea Rev, 1993, 121:2814-2832. doi: 10.1175/1520-0493(1993)121<2814:DOASGR>2.0.CO;2 [25] 成安宁, 陈文, 黄荣辉.积云对流参数化方案对气候数值模拟的影响.大气科学, 1998, 22(6):814-824. http://www.cnki.com.cn/Article/CJFDTOTAL-DQXK806.001.htm [26] Huang Ronghui, Wu Bingyi, Sung H G, et al. Sensitivity of numerical simulations of the East Asian summer monsoon rainfall and circulation to different cumulus parameterization schemes. Adv Atmos Sci, 2001, 18(1):23-41. doi: 10.1007/s00376-001-0002-8 [27] Ding Y H, Liu Y J. Onset and the evolution of the summer monsoon over the South China Sea during the SCS MEX field experiment in 1998. J Meteor Soc Japan, 2001, 79(1B):255-276. doi: 10.2151/jmsj.79.255 [28] Hewitson B C, Reason C, Jennant W, et al. Dynamic modeling of the present and future climate system. Technical Report to the Water Research Commission. Pretoria, South Africa, 2004.