Higher Resolution Better Simulation Low Resolution High Resolution

Higher Resolution – Better Simulation Low Resolution High Resolution

FLOPS: Floating point operations per second WMO: 2002

Clouds in GCMs - What are the problems ? Many of the observed clouds and especially the processes within them are of subgrid-scale size (both horizontally and vertically) GCM Grid cell 40 -400 km

云-降水过程是多种复杂的动 力和热力过程相互作用的结果 radiation convection microphysics turbulence dynamics

云参数化方案 • 给定气候云(Manabe et al, 1965, Washington and Kasahara, 1970) • 根据相对湿度、垂直速度和稳定度诊 断云(Slingo, 1987) • 显式预报云中液态水和云量(Sundqvist, 1978; Rockner et al, 1987; Le Treut and Li, 1989；Tiedtke ，1993)

Key (sub)-tropical Cloud-types

云辐射强迫 LWCRF = Fclr - F SWCRF = S( clr - ) Net CRF = LWCRF + SWCRF

部分参考文献: Comparing Cloud Radiative properties between the Eastern China and the Indian Monsoon Region. Rucong Yu, Yongqiang Yu and Minghua Zhang, 2001, Advances in Atmospheric Sciences, Vol. 18, No. 6， 1090 -1102 Climate effects of the deep continental stratus clouds generated by the Tibetan Plateau，Rucong Yu, B. Wang, and Zhou Tianjun，2004, J. Climate. Vol. 17, No. 13, pp. 2702 -2713. The Impacts of Low-level Cloud Over the Eastern Subtropical Pacific On the “Double ITCZ” in LASG FGCM-0, Fushan Dai, Rucong Yu, Xuehong Zhang, Yongqiang Yu and Jianglong Li, 2003, Advances in Atmospheric Sciences， Vol. 20, No. 3, 461 -474 On the observed near cancellation between longwave and shortwave cloud forcing in tropical regions. J. T. Kiehl, 1994, J. Climate, 7, 559 -565. The seasonal cycle of low stratiform clouds. S. A. Klein and D. L. Hartmann, 1993, J. Climate, 6, 1587 -1606. Warm pool heat budget and shortwave cloud forcing: A missing physics? Ramanathan, V. , B. Subasilar, G. J. Zhang, W. Conant, R. D. Cess, J. T. Hiehl, H. Grassl, and L. Shi, 1995, Science, 267, 499 -503. Impact of the convection-wind-evaporation feedback on surface climate simulation in general circulation models, M. H. Zhang, 1996, Climate Dynamics, Vol. 12, 299 -312 The Role of Large-Scale Atmospheric Circulation in the Relationship between Tropical Convection and Sea Surface Temperature, K. -M. LAU, 1997, Journal of Climate, Vol. 10, 381 -392