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1.
9000年前古气候的数值模拟研究   总被引:5,自引:1,他引:5  
王会军  曾庆存 《大气科学》1992,16(3):313-321
本文用大气物理所的全球大气环流模式模拟了9000年前一月份和七月份的古气候.得出:北半球夏季由于地球轨道参数的变化引起的比现在多7%的太阳辐射使得温度升高了,尤其是高纬地区,海陆对比的加强又增强了季风,季风区域降水增加了;而冬季因为太阳辐射在北半球减少了7%,温度变低了.这些结果与现有的古气候证据相一致,并与其他模拟结果进行了较详细的比较,还作了进一步的讨论.  相似文献   

2.
The Interannual Variability of Climate in a Coupled Ocean-Atmosphere Model   总被引:2,自引:0,他引:2  
In this paper, the interannual variability simulated by the coupled ocean-atmosphere general circulation model of the Institute of Atmospheric Physics (IAP CGCM) in 40 year integrations is analyzed, and compared with that by the corresponding IAP AGCM which uses the climatic sea surface temperature as the boundary condition in 25 year integrations.The mean climatic states of January and July simulated by IAP CGCM are in good agreement with that by IAP AGCM, i.e., no serious ‘climate drift’ occurs in the CGCM simulation. A comparison of the results from AGCM and CGCM indicates that the standard deviation of the monthly averaged sea level pressure simulated by IAP CGCM is much greater than that by IAP AGCM in tropical region. In addition, both Southern Oscillation (SO) and North Atlantic Oscillation (NAO) can be found in the CGCM simulation for January, but these two oscillations do not exist in the AGCM simulation.The interannual variability of climate may be classified into two types: one is the variation of the annual mean, another is the variation of the annual amplitude. The ocean-atmosphere interaction mainly increases the first type of variability. By means of the rotated EOF, the most important patterns corresponding to the two types of interannual variability are found to have different spatial and temporal characteristics.  相似文献   

3.
The seasonal cycle of the climate of 9000 years before present was simulated with the IAP two-level atmospheric general circulation model. The incoming solar radiation was specified from the orbital parameters for 9000 years Ago. The boundary conditions of that time were prescribed to the present value because of the small differences between the two. The change in radiation makes temperature to be higher in summer and lower in winter over large areas of the land; and the increased temperature contrast between the land and the ocean strengthens the summer monsoon circulation and increases the precipitation over there. The asymmetry of temperature change between the Northern Hemisphere and the Southern Hemisphere and between summer and winter still exists, which agrees with that get from the previous perpetual experiments.  相似文献   

4.
Based on time series and linear trend analysis, the authors evaluated the performance of the fourth generation atmospheric general circulation model developed at the Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP AGCM4.0), in simulating surface air temperature (SAT) during the twentieth century over China and the globe. The numerical experiment is conducted by driving the model with the observed sea surface temperature and sea ice. It is shown that IAP AGCM4.0 can simulate the warming trend of the global SAT, with the major warming regions in the high latitudes of the Northern Hemisphere and the mid-latitudes of the Southern Hemisphere. While the simulated trend over the whole globe is close to the observation, the model under-estimates the observed trend over the continents. More-over, the model simulates the spatial distribution of SAT in China, with a bias of approximately-2°C in eastern China, but with a more serious bias in western China. Compared with the global mean, however, the correlation coefficient between the simulation and observation in China is significantly lower, indicating that there is large uncertainty in simulating regional climate change.  相似文献   

5.
张弘  陈月娟  毕训强 《大气科学》1999,23(3):340-348
为了探讨南极臭氧洞对全球气候的影响状况,我们用IAP_9层全球大气环流模式进行了南极臭氧洞气候效应的数值试验。本文分析了本次试验中南极臭氧洞引起的大气辐射加热场的变化,结果表明,南半球高纬和极地平流层臭氧含量的严重减少,不仅影响该地的大气辐射加热场,同时也使北半球平流层大气的辐射加热场发生改变。虽然对流层中层所受影响较少,但对流层下层南北半球的大气总辐射加热率的变化却相当明显,这些影响将使全球大气温度场产生明显变化。  相似文献   

6.
在Version 2的基础上,对短波辐射方案进行进一步的改进:引入了新增非灰体气体吸收效应、冰晶粒子形状效应和尺度效应以及云的不均匀性效应(称为Version 3)。数值模拟试验结果表明:Version 3能更好地模拟出全球冬、夏季的降水场、海平面气压场及地表气温场的主要分布特征,并且能相当准确地反映出这几个场的季节性变化特征。Version 3对这3个场的模拟能力明显优于原版本(Version 1)。此外,它对东亚地区的季风降雨具有很好的模拟能力,能较好地反映东亚区域降水的季节性变化。可见,Version 3为进一步研究云-辐射相互作用提供了很好的模式基础。本工作还清楚地表明,模式的进一步发展必须进行对相关物理过程中各个因子的更精确刻画,只有这样,模式才能得到更好的模拟能力。  相似文献   

7.
基于中国科学院大气物理研究所新一代大气环流模式IAP AGCM 4.1共30 a(1981—2010年)的集合回报试验结果,评估了模式对淮河流域夏季降水的预报技巧。分析结果表明,模式总体上可以较好地再现出淮河流域夏季平均降水南多北少的空间分布特征,其中模式模拟的6月降水量与观测值的空间相关可达0.93。但降水强度与观测相比具有系统性的偏差,且模式模拟的降水年际变率显著偏弱。基于降水距平相关系数的确定性预报技巧分析表明,模式对流域西南部夏季降水的预测技巧较高,达到0.2以上,且模式对6月降水异常的预测能力相对最好,7月次之。针对淮河不同子流域的预报技巧分析表明,IAP AGCM 4. 1对蚌埠、鲁台子、王家坝水文控制站以上集水面积的夏季面雨量异常具有一定的预报技巧,30 a集合回报的时间相关系数分别为0. 11、0. 13、0. 16。基于降水等级的概率预报技巧评估表明,模式对7月淮河流域南部少雨事件具有很好的预报能力,同时对6月流域中部多雨事件的预报技巧也较高。  相似文献   

8.
孙岚  吴国雄  孙菽芬 《气象学报》2000,58(2):179-193
利用陆面过程模式 SSi B与 IAP/LASG发展的 L9R1 5AGCM的耦合 1 0 a积分试验 ,研究了全球尺度大气与地表的水分和能量交换以及陆地与大气环流和气候的相互作用。模拟表明 :SSi B模式可模拟出陆地上较为真实的表面通量及其日变化 ,较好地定量描述土壤 -植被 -大气连续体系 ( SPAC)中能量和水分的传输过程。因此 ,将其引入气候模式中能够模拟出比 CTL- AGCM更合理的气候平均状态、水汽分布以及水汽输送的气候特征 ,特别是亚洲夏季风水汽输送独特的地域性 ,再现了大气环流 ,尤其是陆面气候的基本特征。并指出 ,陆面过程参数化的引进及其陆面状况的变化显著地改善了全球陆地上的水分平衡状况。利用改进的再循环降水模式 ,进一步研究了陆面过程参数化明显改进降水模拟的物理机制。指出全球陆地 ,特别是盛夏北半球干旱、半干旱地区的再循环降水率明显减小 ,与陆面上表面潜热通量的显著减小区一致 ,从而克服了许多未耦合陆面过程的 AGCMs因对地表水过程非常简单地参数化导致的普遍存在着整个陆地降水偏高 ,改善了全球陆地上的水分平衡状况。因此 ,在充分耦合的陆气环流模式中模拟的降水分布与实况接近。  相似文献   

9.
TheEfectofHeatingAnomalyontheAsianCirculation-AGCMExperiment①WangHuijun(王会军)LASG,InstituteofAtmosphericPhysics,ChineseAcademy...  相似文献   

10.
A numerical experiment was done by using the IAP 9-Level AGCM to study the effects of radiation anomaly over East Asia on the Asian general circulation. The results show that the changes of Asian summer general circula-tion are remarkable in the Indian and China southwest monsoon, precipitation in India and the Yellow River and Huaihe River valley in China and area around the north Japan, the easterly anomaly of low-level zonal wind in the tropical Pacific and so on.  相似文献   

11.
高辉  薛峰 《应用气象学报》2006,17(3):266-272
基于1979—2000年的NCEP/NCAR海平面气压和位势高度场资料分析了南半球大气环流的准半年振荡 (半年波) 现象。结果表明:这一现象主要出现在南半球对流层低层的中高纬度和中高层的热带地区。对南半球热带外大气而言, 40°S和65°S是低层大气环流准半年振荡最为显著的两个纬度带, 半年波的贡献都超过了70%, 低层南半球中高纬度海平面气压场季节变化的反位相也主要体现为各自半年波分量变化的反位相。在此基础上, 检验了IAP 9L AGCM (大气物理研究所9层大气环流模式) 对这一现象模拟的能力, 模拟结果显示, 模式成功模拟了65°S处海平面气压场的准半年振荡现象, 其振幅略低于观测结果, 但模式对40°S处气压场准半年振荡的模拟效果较差。  相似文献   

12.
Using reanalysis data as a benchmark,the authors evaluate the performance of an Atmospheric General Circulation Model(AGCM) named GAMIL(Grid-point Atmospheric Model of LASG/IAP).GAMIL is used to simulate the tropospheric temperature anomalies associated with the El Nio-Southern Oscillation(ENSO) in boreal winters for the period 1980-99.The results show that the symmetrical components of temperature anomalies simulated by GAMIL closely resemble those in the reanalysis data in spatial patterns,especially in the Northern Hemisphere.The limitation of the model is that the simulated cold anomaly over South Asia is located to the east of the reanalysis.The observed temperature anomalies in the South Pacific and the high latitudes of the Southern Hemisphere are not evident in the simulation.The maximum value is 0.8 K smaller and the minimum value is-0.4 K smaller than the reanalysis.The difference between the simulation and the reanalysis is more evident in the regional features of the asymmetrical components of the temperature anomalies.Our results demonstrate that the previously discovered weak response of the GAMIL model to specified sea surface temperature forcing is dominated by the symmetric(asymmetric) component in the tropics(extra-tropics).  相似文献   

13.
游性恬  谷湘潜 《大气科学》1997,21(5):545-551
利用IAP二层全球大气环流模式,进行改变地球自转速度下冬季大气环流及气候异常的数值模拟。其中试验1: 设25 h/d (350 d/a);试验2:设23 h/d (381 d/a);控制运行:24 h/d (365 d/a)。联系从古至今地球自转逐渐减慢的情况,主要讨论地转减慢对冬季大气环流和气候的影响。结果表明,地球自转速度减慢以后,能使西风急流加强,南极附近增温。  相似文献   

14.
p—σ混合坐标原始方程模式对地气交换的敏感性试验   总被引:1,自引:1,他引:0  
赵鸣  高磊 《高原气象》1998,17(2):150-157
在五层及九层p-σ混合坐标有限区域原始方程模式中,选择几种方案对影响地气系统之间动量、热量交换的拖曳系数进行了敏感性试验,并以一次寒潮为试验个例。试验结果表明:模式结果对拖曳系数的选取是敏感的;原模式对该系统在青藏高原地区的取值偏小,增大高牟地区的CD取值能取得更好的预报效果。  相似文献   

15.
IAP AGCM4.0模式对热带大气季节内振荡的模拟评估   总被引:1,自引:1,他引:0  
基于中国科学院大气物理所大气环流模式IAP AGCM4.0总共30年(1979~2008年)的模拟结果,评估了IAP AGCM4.0模式对热带大气季节内振荡的模拟能力。分析结果表明IAP AGCM4.0模式可以在一定程度上模拟出热带大气季节内振荡的主要时空谱结构特征,在周期30~80天处存在明显的谱能量中心;模式模拟的季节内振荡东传的主要特征与观测基本一致,东移波的能量远大于西移波。基于RMM指数(All-season Real-time Multivariate MJO Index)的分析表明,模式模拟的850 h Pa和200 h Pa季节内尺度风场和对流活动在赤道地区的空间分布与观测基本一致。但与观测相比,模式模拟的热带大气季节内振荡的周期较短,东传速度快于观测,虚假的西传特征过强,对流活跃区域范围较小、强度较弱。就非绝热加热而言,模式模拟结果与再分析资料比较接近,但最大加热在印度洋和西太平洋地区出现的位相较晚。进一步分析表明,模式中影响对流触发的相对湿度阈值(RHc)的不同取值(RHc分别取为85%、90%、95%和100%),可以显著影响热带大气非绝热加热垂直廓线,从而影响模式对热带大气季节内振荡的模拟;当对流触发相对湿度阈值取为90%时,IAP AGCM4.0模式对热带大气季节内振荡模拟的能力相对最好,非绝热加热垂直廓线在不同位相的分布特征也与再分析资料最为接近。这说明模式对流参数化方案中不同参数的合适选取,可以改进模式对热带大气季节内振荡的模拟能力。  相似文献   

16.
南半球臭氧变化气候效应的数值模拟   总被引:3,自引:0,他引:3  
采用一个陆气耦合的9层谱模式模拟了南半球臭氧减少所产生的气候效应。数值试验结果表明,南半球臭氧的减少不仅对南半球温度场的 大气环流有影响,而且对北半球的温度场结构和大气环汉也有一定的影响。其气候效应具有全球性。南半球臭氧减少总体上可以使平流层中层以上大气降温、平流层低层增温、对流层顶附近降温。此外,在北半球冬半年期间,南半球臭氧的减少可使南北半球的副热带西风急流都减弱,极锋急流都增强;在北半球夏半  相似文献   

17.
To get more insight into the impacts of land surface processes on climate, a simplified biosphere model (SSiB) developed by Sellers and Xue et al. is implemented into the LASG / IAP spectral climate AGCM (R15L9). The new model has been integrated for more than twenty years. The diagnoses of the integration show that the implementing of the land surface processes has greatly improved the simulation of July climate. It is also shown that the seasonal variations of land surface characteristics have great impacts on the onset of summer monsoon, especially the seasonal march of wind at 850 hPa and precipitation over the regions of summer monsoon.  相似文献   

18.
The "climate draft" often occurs in the coupling process of the atmospheric general circulation model (AGCM) and oceanic general circulation model (OGCM).One of the main methods to overcome the "climate draft" is to simulate the flow and temperature fields in the low-layer correctly.Therefore we designed a three-level AGCM including a planetary boundary layer (PBL) and have run it seven model years to do climate simulation.The results show that the simulated lower level air flow,surface air temperature and sea-level pressure in January and July,approximate to the climate average fields,especially in Asian monsoon area.The simulated upper level flow and geopotential height are also in better agreement with the observed fields.Moreover,the two westerly jets over the northern and southern sides of the Qinghai-Xizang Plateau in winter,the disappearance of its southern subtropical jet during the seasonal transition from spring to summer,the establishment of the two easterly jets near the equator and over the subtropical region during the seasonal transition,are also simulated well.In the mainland of China,the seasonal abrupt shift of the rainfall belt,such as the Meiyu belt in South China during April to May,which jumps to the Changjiang River region in June,again jumps back to the north China in July,and rapidly withdraws to the south in August,are simulated very well.Now we are coupling this model to a global six-level OGCM and nesting a fine mesh (1°×1.25°)regional climate model over China area with it.  相似文献   

19.
ModellingtheInterannualVariationofRegionalPrecipitation over ChinaWangHuijum(王会军)(LASG,InstituteofAtmosphericPhysics,ChineseA...  相似文献   

20.
陈丽娟  吕世华 《高原气象》1996,15(1):112-121
在美国NMC AGCM模式的基础上,参照COLA低分辨率AGCM模式,移植和改进了一个包括植被层陆面过程的陆-气耦合全球大气环流谱模式。其水平分辨率为菱形截断15波,垂直方向分为9层,陆面过程采用简化的简单生物圈模式。  相似文献   

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