中国热带地区降水与印度夏季风的关系

中国热带地区降水与印度夏季风的关系ＳｏｎｇＹａｎｇＷｉｌｌｉａｍＪ．Ｇｕｔｏｗｓｋｉ，Ｊｒ．（美国马萨诸塞州大气与环境研究公司）（美国衣阿华州立大学地质与大气科学系）１引官亚洲季风是东亚和南亚广大地区年降水循环的显著特征。由于其经济和科学上的重要性，...     

大尺度季风环流的季节变化

一、经向环流 850hPa和200hPa上的逐月大尺度季风环流在早先许多研究中已有论述(如Krishnamurti,1985年)。Krishnamurti指出:东亚西南季风地面气流从5月份开始发展;并在7、8月份到达东亚最北部;9月间季风气流撤回到赤道15°以内热带深处。根据中国科学院大气物理研究所提供的10年月平均资料计算得出的结果表明,4月间垂直环流是由赤道附近和中国中部的上升运动这两种环型组成。赤道附近的上升运动可能与马来西亚半岛对流活动和降雨有联系。实际风大小     

Variations in the atmospheric electric field at tropical station during 1930–1987

The variations noticed in the atmospheric electric field recorded at Pune (18o32’N, 73o51’E, 559 m ASL), a tropi-cal inland station located in Deccan Plateau, India, during the period 1930-1987, have been examined in relation to the variations observed in the Angstrom turbidity coefficient (β) and selected meteorological parameters. The month-ly and annual mean values of the atmospheric electric field, Angstrom turbidity coefficient (β), rainfall, temperature and relative humidity for the years 1930-1938, 1957-1958, 1964-1965, 1973-1974 and 1987 were considered in the study.The results of the above study indicated gradual increases in the atmospheric electric field over the period of study (1930-1987) which is statistically significant at less than 5% level. The increases noticed during different periods varied from 30 to 109 %. The increase noticed during the period (1930-1938) and (1973-1974) was maximum (109%). The Angstrom turbidity coefficient also showed systematic increases during the period of study, which is consistent. The diurnal curve of the atmospheric electric field at the station by and large, showed a double oscillation, which is generally observed in the continental environments.     

上空有云流流出的台风的强度变化

一、导言 Erickson 和 Winston,(1972)第一次从气象卫星云图上观测到从西北太平洋的一个命名热带气旋(以下不管其强度,一概称为台风)的中心偶尔有范围很大的一股含有中云和高云的云流向东北方流出。作者们指出,这种云流是由大量的热带的热量和水汽输送到西风带里去造成的。Ramage(1974)研究了中国南海1970年10月的3个台风,得到的结论是:高空云流外流是由于在对流层上层有西风槽逼近而在槽前又有热通量的辐散所引起的。他还发现,在槽线以东的涡度平流会增强台风上空的质量辐散,而在云流形成时,风速也随之加大。他的这个发现与Riehl(1972)的结论是一致的,     

The possible influences of the increasing anthropogenic emissions in India on tropospheric ozone and OH

A 3-D chemical transport model (OSLO CTM2) is used to investigate the influences of the increasing anthropogenic emission in India. The model is capable of reproducing the observational results of the INDOEX experiment and the measurements in summer over India well. The model results show that when NOx and CO emissions in India are doubled, ozone concentration increases, and global average OH decreases a little. Under the effects of the Indian summer monsoon, NOx and CO in India are efficiently transported into the middle and upper troposphere by the upward current and the convective activities so that the NOx, CO, and ozone in the middle and upper troposphere significantly increase with the increasing NOx and CO emissions. These increases extensively influence a part of Asia, Africa, and Europe, and persist from June to September.     

Impact of Aircraft NOx Emission on NOx and Ozone over China

A three-dimensional global chemistry transport model (OSLO CTM2) is used to investigate the impact of subsonic aircraft NOx emission on NOz and ozone over China in terms of a year 2000 scenario of subsonic aircraft NOx emission. The results show that subsonic aircraft NOx emission significantly affects northern China, which makes NOx at 250 hPa increase by about 50 pptv with the highest percentage of 60% in January, and leading to an ozone increase of 8 ppbv with 5% relative change in April. The NOx increase is mainly attributed to the transport process, but ozone increase is produced by the chemical process. The NOx increases by less than 10 pptv by virtue of subsonic aircraft NOx emission over China,and ozone changes less than 0.4 ppbv. When subsonic aircraft NOx emission over China is doubled, its influence is still relatively small.     

青藏高原黑碳气溶胶传输及沉降的季节特征模拟分析

根据全球气溶胶气候模式GEM-AQ/EC的1995~2004年模拟,分析了青藏高原大气黑碳气溶胶的来源、传输及沉降季节特征。研究表明:青藏高原黑碳气溶胶主要来自自由对流层和大气边界层的输送。相对于自由对流层的黑碳输送,紧邻青藏高原的南亚、东亚以及东南亚大气边界层的输送更有效,它形成了青藏高原由北向南、自西往东黑碳气溶胶浓度和沉降明显递增的基本分布形态。横跨欧亚大陆自由对流层的黑碳气溶胶由西向东向青藏高原的输送全年不变,夏季输送路径最北但强度最弱,冬季路径最南而强度最强。大气边界层黑碳气溶胶的输送受控于亚洲季风环流变化,来自南亚的黑碳气溶胶在春季越过孟加拉湾传输进入高原东南部,夏季则可翻越喜马拉雅山抵达青藏高原南部腹地;同时我国中部排放的黑碳气溶胶也在东亚夏季风向北扩展中驱动它从东向西往青藏高原东北部传输。从秋季到冬季,随着夏季风撤退,南亚黑碳源区向青藏高原传输衰退,东亚冬季风的反气旋性环流的南侧及西南侧的偏东风携带秋季我国东南部源区和冬季东南亚源区黑碳气溶胶向青藏高原东南部传输。受青藏高原明显的暖湿季和干冷季气候影响,干湿沉降分别主导了青藏高原冬季和夏季黑碳沉降,夏季青藏高原黑碳气溶胶沉降总量大多超过8~10 kg·km-2,在高原东北部的最高值超过40 kg·km-2。冬季青藏高原黑碳气溶胶沉降量最低,大部地区黑碳沉降低于5 kg·km-2。青藏高原黑碳沉降的冬夏季节相差约为2~8倍。     

克里雅河下游及圆沙古城脊椎动物考察记录

克里雅河发源于昆仑山脉,位置在新疆的南部。2001年10月18-11月22日,中法联合考察队对克里雅河下游进行了深入的调查。根据标本采集与资料统计,克里雅河流域的野生脊椎动物约有98种（包括已绝迹的几种）,隶属于5纲,24目,48科。其中,鱼类约4种;两柄类1种;爬行类约4种;鸟类70种;兽类约19种。有一些动物的遗骸发掘自圆沙古城及附近的古墓地。本文探讨了物种绝迹的原因。     

SHORT COMMUNICATION COMMENTS ON THE RESIDUAL BILINEARIZATION METHOD

Through theoretical analysis and computer simulation,this short communication comments on theresidual bilinearization(RBL)method and compares it with non-bilinear rank annihilation(NBRA)forthe treatment of second-order calibration with non-bilinear data.It is found that these two methods aremathematically equivalent but have different noise propagation properties.The second-order advantage,namely quantitation in the presence of unknown interferences,can be carried over to non-bilinear dataonly if there exists a net analyte rank(NAR)for the analyte of interest.     

FINDING CAUSES OF OUTLIERS IN MULTIVARIATE ENVIRONMENTAL DATA

Multivariate outliers in environmental data sets are often caused by atypical measurement error in a singlevariable.From a quality assurance perspective it is important to identify these variables efficiently so thatcorrective actions may be performed.We demonstrate a procedure for using two multivariate tests toidentify which variable‘caused’each outlier.The procedure is tested with simulated data sets that havethe same correlation structure as selected water chemistry variables from a survey of lakes in the WesternUnited States.The success rates are evaluated for three of the variables for sample sizes of 50 and 100,significance levels of 0.01 and 0.05 and various amounts of mean shift.The procedure works best forhighly correlated variables.