QINGHAI-XIZANG SURFACE LONG-WAVE RADIATION PARAMETERIZATION WITH ITS CLIMATIC CALCULATION^*     

Gao Ge  Zhang Lanying  Weng Duming 《Acta Meteorologica Sinica》1998,12(2):190-198

In the context of August 1982- July 1983 radiation balance data of the Qinghai-Xizang Plateau, detailed study is made of the relation between the active-surface temperature and surface temperature, proposing two parameterization schemes on surface long-wave radiation(SLWR)of the form U=kδσ(T₀+273)⁴ and U=δσ[(T₀+273)⁴+△T)]⁴, where k and △T are indicated by parameterization equations, separately, others being in conventional notation. Retrieved verification shows the two formulae to be of the same fitting accuracy with the mean relative error of 3.6% and suitable for computing instantaneous and mean flux density, alongside analyzed daily and annual variations of k and △T. Eventually. SLWR in the target area is investigated and its climatic characteristics examined.  相似文献   

The influences of boundary layer parameterization schemes on mesoscale heavy rain system   总被引：2，自引：0，他引：2  

Xu Liren  Zhao Ming 《大气科学进展》2000,17(3):458-472

1.Introducti0nThemesoscaleoperationalmodel-whichisoftenused,isMM4orMM5'butMM4isusedfrequentlyonlO3kmscale.Thephysicalprocessesinthismodeldevelopconstantly.FororiginalMM4,thecomputationofsurfacefluxesisnotaccurate,andKmodelfortheturbu-lencefluxesbetweenany2levelsneedstobeimprovedbynewtreatment.Inordertostudytheinfluencesofboundarylayerparameterizationschemesonmesoscaleheavyrainsystem,sur-facefluxesandKmodelinoriginalMM4areimprovedbytherecentresearchinthispaPer.Theflux-profilerelationsforv…  相似文献   

A Simulating Study on Resolvable-Scale Microphysical Parameterization in a Mesoscale Model   总被引：3，自引：1，他引：2  

Lin Wenshi  Fong Soikun  Wu Chisheng  Ku Chimeng  Wang Anyu  Yang Yan 《大气科学进展》2000,17(3):487-502

The Penn State/ NCAR Mesoscale Model (MM5) is used to simulate the precipitation event that oc-curred during 1-2 May 1994 to the south of the Yangtze River. In five experiments the Kain-Fritsch scheme is made use of for the subgrid-scale convective precipitation, but five different resolvable-scale microphysical parameterization schemes are employed. They are the simple super-saturation removal scheme, the warm rain scheme of Hsie et al. (1984), the simple ice scheme of Dudhia (1989), the complex mixed-phase scheme developed by Reisner et al. (1993). and the GSFC microphysical scheme with graupel. Our interest is how the various resolvable-scale schemes affect the domain-averaged precipitation, the pre-cipitation distribution, the sea level pressure, the cloud water and the cloud ice.Through a series of experiments about a warm sector rainfall case, results show that although the dif-ferent resolvable-scale scheme is used, the differences of the precipitation characteristics among all five runs are not very obvious. However, the precipitation is over-predicted and the strong mesoscale low is produced by the simple super-saturation removal scheme. The warm rain scheme with the inclusion of condensation and evaporation under-predicts the precipitation and allows the cloud water to reach the 300 hPa level The scheme of the addition of graupel increases the resolvable-scale precipitation by about 20%–30%. The inclusion of supercooled liquid water in the grid-scale scheme does not affect significantly the results.  相似文献   

水汽场初值调整及其对华南降水预报贡献的研究   总被引：6，自引：2，他引：4       下载免费PDF全文

常越  何金海 《应用气象学报》2000,11(1):35-46

该文利用GMS多通道气象卫星资料推导得到的降水资料估算出的加热率, 作为非绝热的非线性正规模初始化过程中的非绝热强迫项, 进行风压场的初值调整, 再采用一个与模式中的对流参数化方案相反的逆运算方案, 进行水汽场的初值调整.以保证初始时刻按模式的物理参数化方案计算得到的加热率与由卫星推导的加热率一致. 这一方法在非绝热的非线性正规模初值化的框架中, 使初始时刻的水汽场得到调整.既实现了传统的初始化目标, 又提高了模式对降水的短时预报效果.对华南的两个个例的试验结果表明该文的方法是有效的.  相似文献   

EFFECTS OF BOUNDARY LAYER PARAMETERIZATION ON THE MONTHLY MEAN SIMULATION   总被引：11，自引：0，他引：11  

张琼  钱永甫 《Acta Meteorologica Sinica》1999,(1)

Treatments of the boundary layer in a five-layer primitive equation model with mixed P—σcoordinates are improved by incorporating similarity theory,which is widely used at present.Twokinds of parameterization schemes of the boundary layer are designed,and static test and numericalsimulation are performed.It is found that the iterative scheme can fairly improve the simulation ofthe mean climate field in July.The abnormally strong heat low over the Tibetan Plateau isweakened to some extent.  相似文献   

Betts对流调整方案在移动套网格台风数值模式中的初步试验   总被引：1，自引：1，他引：0       下载免费PDF全文

刘宇迪  翟子航 《气象科学》1999,19(4):335-342

Betts对流调整方案采用的是垂直温湿场向观测的准平衡热力结构松驰的方法。本文在一个考虑了台风初值化的移动套网格台风数值模式中,对Betts方案进行了初步试验。结果表明：Betts方案能较好的预报出台风移动的路径和降水过程,并在台风路径、降水落区预报以及对流增温的垂直分布等方面都略优于Kuo方案的预报结果。  相似文献   

Some remarks on cumulus parameterization     

R. S. Lindzen 《Pure and Applied Geophysics》1988,126(1):123-135

A simple parameterization of cumulonimbus convective heating is presented. The model is primarily based on preserving a moisture budget and on detraining cloud air at levels corresponding to the neutral buoyancy of the air converged at low levels. Results are compared with data from the western Pacific and GATE. Agreement is good. Suggestions are offered for improving the model and extending it to other regions.  相似文献   

中尺度数值模式中湿过程参数化的敏感性试验          下载免费PDF全文

俞小鼎  E. Richar  R. Rosset 《大气科学》1995,19(6):645-653

本文利用一个三维中尺度模式，分别采用两种不同的湿过程处理方案ＦＰＡ和ＮＣＡ模拟同一个洋面冷锋个例，以考察模拟结果对湿过程参数化方案的敏感性。两种方案的区别在于前一种使用了次网格湿对流参数化而后者没有。通过比较分别使用ＦＰＡ和ＮＣＡ方案所进行的模拟ＦＰＳ和ＮＣＳ，发现冷锋结构在两者间出现较大差异。从８５０ hPa等压面|Δθe|等值线图所显示的结构看，ＮＣＳ中冷锋呈现为一长一短两条锋带，而ＦＰＳ中冷锋仅呈现为一条锋带。在相应的冷锋横向垂直剖面中，ＮＣＳ中存在两个相邻的锋面垂直环流，而ＦＰＳ中只有一个。另外，ＮＣＳ中对流不稳定的冷锋区出现垂直运动过分发展的现象，而ＦＰＳ中不存在这个问题。通过与卫星云图比较，我们注意到，ＮＣＳ中尽管出现了垂直运动过分发展的现象，但相对于ＦＰＳ而言，其模拟的冷锋结构与实际较为接近，成功地模拟出云图上显示的双冷锋结构。ＮＣＳ中垂直运动过分发展的一个重要原因是模式中采用的静力平衡近似。ＦＰＳ中次网格对流参数化方案的使用，通过减少甚至消除对流不稳定度，一方面使垂直运动的过分发展倾向受到约束，另一方面也可能使在对流不稳定层结下的锋区环境中本应出现的中尺度结构失去了形成的机会。  相似文献   

国外中期数值预报业务模式的性能及发展趋势   总被引：1，自引：0，他引：1       下载免费PDF全文

杨学胜 《气象》1997,23(1):3-10

作者简单介绍了国内预报员较为熟悉的欧洲中期天气预报中心，美国国家气象中心和日本气象厅三个中期预报模式的性能及预报效果，包括近几年颇为流行的半拉格朗日时间积分方案，物理过程参数化方案的完善和改进，中期数值预报业务模式的发展趋势等。  相似文献   

SOME NEW UNDERSTANDINGS OF LAND-SURFACE PROCESSES IN ARID AREA FROM THE HEIFE     

胡隐樵  高由禧 《Acta Meteorologica Sinica》1996,(2)

The survey for the HEIFE(Atmosphere-Land Surface Processes Experiment at Heihe RiverBasin,Western China)is given in the paper.The following basic subjects for land-surface process-es in arid areas are studied:(1)the general characteristics of the energy budget on ground surfacein arid areas;(2)the parameterization of the land surface processes;(3)the interaction betweenoasis and its desert circumstances,a special phenomenon in arid areas.The analysis shows that thesensible heat flux in the surface energy budget is in the majority,and the latent heat flux may beneglected.The influence of atmospheric stratification stability on the turbulent transfer of energyand substance must be considered in parameterization of land surface processes in arid areas.The“cold island effect”phenomenon in oasis and the“humidity inversion”phenomenon in desert nearoasis are the result of the interaction between them.The results would improve the understandingof land surface processes in arid areas.  相似文献