陆面过程模式CoLM和NCAR_CLM3.0对中国典型森林生态系统陆气相互作用的模拟Ⅰ.不同模式模拟结果的初步分析

量为期1年的日均值的模拟为例,COLM和CLM3.0在长白山观测站模拟值和观测值时间序列的相关系数分别为0.80和0.65,在千烟洲站分别为0.69和0.64,均通过了0.01的信度检验;两个模式对全年平均的模拟与观测日平均值的比值在长白山分别为1.21和0.86,在千烟洲分别为0.83和0.60.研究结果表明,这两个陆面过程模式可以作为研究这两种典型森林生态系统陆气交换的基本工具.同时,对模式模拟性能差异的深入分析将有助于进一步改进陆面模式的参数化过程,为相关研究奠定更坚实的基础.     

东亚高空急流协同变化对冬季欧亚遥相关型气候效应的影响

利用NCEP/NCAR再分析资料和我国地面735站气温和降水资料,首先分析了欧亚遥相关型的时间演变和结构特征,在此基础上探讨了欧亚遥相关型不同位相时东亚大气环流的差异,并进一步研究了欧亚遥相关型影响我国冬季气温和降水过程中东亚高空急流的重要作用。从结构上看,欧亚遥相关型位势高度异常中心位于250 hPa高度,表现出准正压的结构。欧亚遥相关型位于正位相时,东亚温带急流强度偏弱且位置向北移动;副热带急流强度偏强,两支急流在45°N附近有明显分界;西伯利亚高压和阿留申低压强度增强;东亚大槽加深,槽线倾斜不明显。负位相时则相反。欧亚遥相关型与东亚高空急流的联系是其影响我国气温降水的重要原因。正欧亚遥相关型时,偏弱的温带急流区较强的北风分量有利于北方冷空气南下,从而造成我国气温偏低;偏强的副热带急流区增强的南风将副热带地区暖湿空气向北输送,两支急流协同变化,影响我国冬季降水异常的分布。去掉温带急流或副热带急流偏强的年份,欧亚遥相关型与我国温度、降水的相关性显著减弱,说明欧亚遥相关型是通过东亚高空急流协同变化的桥梁,对我国温度和降水异常产生影响。进一步研究发现,欧亚遥相关型与副热带急流的关系不如其与温带急流稳定,导致在欧亚遥相关型同一位相时东亚高空急流存在两种不同的配置,这种高空急流配置的不唯一性使得东亚高空急流能对欧亚遥相关型的气候效应起到调控作用。     

Numerical simulation of the regional ocean circulation in the coastal areas of china

The regional ocean circulation in the coastal areas or China (including a part of the western Pacific Ocean, the South China Sea and the Bay of Bengal el al.) is simulated by using the improved Princeton Uni-versity ocean circulation model (POM). Compared with the modeling results obtained by the large-scale ocean general circulation model (OGCM), the basic ocean circulation features simulated by the regional ocean circulation model are in good agreement with that simulated by OGCM and some detailed character-istics such as the regional ocean circulation, sea temperature, salinity and free sea surface height have also been obtained which are in good accord with the observations. These results indicate that the regional ocean circulation model has good capability to produce the regional ocean circulation characteristics and it can be used to develop coupled regional ocean-atmospheric model systems.     

青藏高原隆升作用于大气临界高度的数值研究

利用Ｐ－σ混合坐标系全球大气环流模式研究了青藏高原隆升作用于大气临界高度问题,通过对数值试验结果的分析进一步证实了在高原隆升的过程中存在着一个临界高度,这个高度在夏季约为１５００～２０００ｍ。当高原总体平均高度超过临界高度后,高原周围地区的气流主要以绕流为主,爬坡气流的速度较小,稳定的高原季风开始形成,高原地区范围内为强大的上升运动区,高原南侧和中国东部地区出现一条明显的雨带,随着高原隆升高度的增高,雨带内的降水量逐渐增加,同时高原西侧附近地区形成一个稳定的感热通量大值带     

CHARACTERISTICS OF 10-DAY MEAN SURFACE SENSIBLE HEAT FLUX VARIATIONS IN THE SCS MONSOON REGION AND POSSIBLE CONNECTIONS WITH THE SCS SUMMER MONSOON ONSET*

The time and space variations of the ten-day mean surface sensible heat flux have been analyzed in this paper based on the data of NCEP/NCAR from January of 1979 to December of 1995 in the South China Sea (SCS) monsoon region.It is found that large variations of the surface sensible heat flux standard deviations exist in the northwestern Indochina Peninsula and the Indian Peninsula regions,and their locations and strength change significantly during the onset period of SCS monsoon.The negative deviations appear evidently earlier in the Indocbina Peninsula than in the Indian Peninsula but the deviation strength in the Indian Peninsula is stronger than that in the Indochina Peninsula.The appearance of the zonal negative mean deviations in the southern part of the Indochina Peninsula corresponds to the date of the SCS summer monsoon onset,while the occurrence of the deviation decrease corresponds to the date of the South Asian monsoon onset.The sensible heat flux increases dekad by dekad before the onset of the summer monsoon in the Indian Peninsula and the Indochina Peninsula and decreases after the monsoon onset.Therefore,the surface sensible heat flux changes in the Indochina and the Indian Peninsula regions maybe have some connections with the SCS monsoon onset and the Indian monsoon onset,and the Indochina Peninsula maybe becomes the sensitive or key region to the SCS monsoon onset and the land maybe plays an important role in triggering summer monsoon onset.     

CHARACTERISTICS OF 10-DAY MEAN SURFACE LATENT HEAT FLUX VARIATIONS IN THE SCS MONSOON REGION AND POSSIBLE CONNECTIONS WITH THE SCS SUMMER MONSOON ONSET

The temporal and spatial variations of the ten-day mean surface latent heat flux (TMLH) havebeen analyzed in this paper based on the data of NCEP from January of 1979 to December of 1995in the South China Sea (SCS) monsoon region. It is found that there exist maximum centers ofTMLH standard deviation in the northwest Indochina and the Indian Peninsula as well as thewestern Pacific, SCS, the Indian Ocean and the Bay of Bengal, and their locations and strengthschange significantly during the period of SCS monsoon onset. A positive zonal deviation of TMLHoccurs first in the Indochina Peninsula, apparently earlier than that in the Indian Peninsula. Theappearance of maximum positive zonal deviations of TMLH approximately coincides with thesummer monsoon onset. Over the Indochina and Indian Peninsulas, the TMLH increases graduallywith a small amplitude of variation before the onset of summer monsoon, and the rate of increase issignificantly enhanced after the onset of the monsoon; whereas over the ocean, TMLH decreasesbefore the monsoon onset, varies little during the period of monsoon and increases gradually afterthe ending of monsoon. Therefore, it seems that the surface latent heat flux plays an importantrole in the maintenance of the summer monsoon, and its variation is an phenomenon accompanyingthe onset of summer monsoon.     

连云港海区养殖优质条斑紫菜原因研究

根据条斑紫菜的生物学特性及不同生育期的生长、发育要求,通过对我国沿海主要海区11～4月的海温、雾、风向、降水量及雨日和海区底质状况分析,得出连云港海区养殖条斑紫菜的客观条件比其他海区优越,所养殖的条斑紫菜品质好的结论。     

东亚副热带急流与东北夏季降水异常的关系

利用东北地区88个气象站点观测的7、8月(夏季)降水量和NCEP/NCAR再分析资料,分析了东北地区夏季降水与同期东亚副热带西风急流之间的关系,发现东北地区夏季降水异常偏多年,位于青藏高原上空200 hPa西风急流中心强度偏强,东北地区上空急流轴向东北方向倾斜;东北地区夏季降水异常偏少年,青藏高原上空200 hPa西风...     

区域海气耦合过程对中国东部夏季降水模拟的影响

本文以区域环境系统集成模式(RIEMS)和普林斯顿海洋模式(POM)为基础,建立了一个区域海气耦合模式,评估了其对1985～2004年中圜东部夏季降水的模拟性能,并通过与观测海温强迫下单独大气模式模拟结果的比较,分析了海气耦合过程对降水模拟性能的影响.结果表明:耦合模式基本能够模拟出中国东部地区夏季降水的气候态分布及中...     

铁岭市近45年气候变化特征分析

利用线性倾向率、滑动平均等方法，对铁岭市1960--2004年间4个气象观测站的月平均气温、降水量、平均最高气温、平均最低气温以及初终霜、无霜期、积温、透雨等资料进行分析，结果发现铁岭市近45年气候变化特点为温度呈上升、降水略减少的趋势，特别是近15年，气温增暖幅度加大，降水春夏两季减少明显；但各季增温幅度差异较大，对气候变暖贡献最大的是冬季，平均最低气温升温幅度明显高于平均最高气温，气温日较差变小；初霜拖后、终霜提前及无霜期延长，积温明显增多，透雨偏晚频率增大，极端气候事件出现的几率增大。