地面报中高山站资料的应用分析   总被引：3，自引：2，他引：1  

郝民  龚建东  徐枝芳 《气象》2016,42(4):424-435

无线电探空仪观测和地面观测资料作为天气分析和数值预报最常用、最重要的两种资料数据源,两者时空分辨率有着明显的差异。如何利用地面观测资料的高时空分辨率特点来补充探空观测资料在一些地区的欠缺和不足,特别是地面高山站资料的使用对对流层底层环流场的影响及对精细化数值天气预报风场分析指示意义等都需要进一步的探究。文章通过对地面高山站资料在资料同化中不同的使用方式的分析,探索其作为探空资料的补充在资料同化中的贡献。个例试验选取2013年6月29日00时地面资料和探空观测资料进行资料同化,试验方法:分别将地面高山站资料作为探空资料和地面资料应用于同化分析中,结果表明:地面高山站资料当探空资料使用时对850和925 hPa风场同化分析有正效果。在地面高山站资料当探空资料使用和当地面资料使用的对比中,其24 h 850和700 hPa高度和风场预报试验差异不显著;但24 h降水预报结果显示:地面高山站资料当探空资料使用对降水强度和位置的预报都有弱的正贡献。连续试验的降水预报检验证明:在地面高山站较多的西南区,高山站资料当探空资料使用在小雨、中雨、暴雨等量级的预报评分要优于高山站资料当地面报使用,且其预报偏差也较小;在中国区降水预报检验高山站资料当探空资料和地面报使用差异不大。  相似文献   

长江中上游冬季山地雾边界层特征及生消过程分析          下载免费PDF全文

费冬冬  牛生杰  杨军  陆春松 《大气科学学报》2016,39(2):221-231

利用2010年12月在湖北宣恩观测山地雾获得的边界层廓线、雾滴谱、能见度资料,分析了该地雾过程的边界层特征及其生消过程。结果表明:1)宣恩山地雾主要由夜间辐射冷却引起,且能见度多在200 m以上;垂直发展深厚,成熟时厚度达到400~600 m。2)夜间风场主要由山风环流控制,风向多为东南风;入夜及雾生前期,地面风速不超过0.5 m/s,雾消前增大至2.0 m/s左右。3)雾生前观测到"C"字型温度层结,中下层气温降温率在0.3~1.0℃/(100 m)之间;结合该时段近地层露点温度逆温,离地200 m左右率先饱和成云;雾消时低空相对湿度依然保持较大值,重新变为空中雾层。4)雾前1~2 h地面及植被表明温度显著上升,个别升温率达1℃/h,对应时段地面相对湿度达到饱和,与其他地区有明显区别,对预报宣恩山地雾有积极意义。  相似文献   

祁连山南麓夏季地形云特征及山谷风影响分析     

刘蓓 《气象科技》2016,44(1):67-75

利用门源、祁连气象站2004—2013年6—8月逐时常规观测资料,分析了地形云的日变化特征,结果表明:两站夏季总、低云量的日变化呈现双峰型特征;层积云和积雨云的日变化呈反相特征。层积云出现频率最高在清晨,积雨云在午后至傍晚出现频率最高;门源站层积云出现频率高于祁连站,而祁连站积雨云出现频率高于门源站。两站山谷风环流特征明显,风速最大值出现在午后,最小值出现在清晨;门源站谷风控制时间长于山风,祁连站山风控制时间长于谷风。两站积雨云出现时间与山谷风风速最大值出现时间之间具有对应关系;有天气系统影响时形成的积雨云,持续时间较长,降水较多;仅由地形风及热力、湍流作用形成的积雨云,持续时间较短,降水较少。层积云的形成有3种类型:第1种由高层云演变而来;第2种由积雨云对流发展受到抑制而形成;第3种由局地山谷风环流形成,云的形成与山谷风环流以及边界层日变化特征相关。  相似文献   

CLIMATOLOGICAL CHARACTERISTICS OF SPRING PRECIPITATION OVER SOUTHERN CHINA AND ITS INTRASEASONAL OSCILLATION     

潘蔚娟  李春晖  蒋承霖 《热带气象学报(英文版)》2016,22(2):233-242

Based on observations and reanalysis data, the characteristics of the evolution of climatological spring precipitation over Southern China (SPSC) and the associated climatological intraseasonal oscillation (CISO) and atmospheric circulation are studied. Results show that SPSC increases in an oscillatory way. Although the evolution of SPSC is similar in different regions, there are also differences. In different regions of Southern China, the onset dates of the rain season are from the 12th to 24th pentad and the peak dates are after the 20th pentad. CISO is an important component of SPSC, which is not only statistically significant, but also accompanies a dynamically coherent structure. The peak wet/dry phase of each CISO cycle corresponds to a significant rainfall increasing/decreasing period and modulates the evolution of SPSC. The rainfall growth in the second half of March and mid-April is the result of the modulation. The wet/dry phase of CISO is accompanied by low-level convergent (upper-level divergent) and cyclonic (anti-cyclonic) circulation, which favors ascending motion to develop over Southern China.  相似文献   

吕梁山地区中—新生代隆升演化探讨   总被引：6，自引：0，他引：6  

赵俊峰  刘池洋  王晓梅  马艳萍  黄雷 《地质论评》2009,55(5):663-672

对吕梁山地区中—新生代隆升时限及其演化的认识,是恢复鄂尔多斯盆地沉积东界的基础,也是探讨华北克拉通演化和破坏等科学问题的有机组成部分。本文以改造盆地与盆山耦合的研究思路为指导,通过对研究区及邻区前中生代地质演化、中生代原始沉积面貌、中生代构造变动与岩浆活动以及新生代以来与相邻地堑发育耦合关系等的分析,并结合裂变径迹测年与热史模拟,认为吕梁山地区在中生代鄂尔多斯盆地发育的主要时期是大型沉积盆地的一部分,与鄂尔多斯盆地经历了同步沉降—抬升过程。晚白垩世以来是吕梁山地区主要的隆升期,可进一步分为缓慢隆升（100～21±2Ma）、加速隆升（21±2～8Ma）及强烈隆升（8Ma以来）3个隆升演化阶段。吕梁山地区中—新生代以来的隆升演化,与相邻鄂尔多斯盆地的抬升消亡及其周边断陷盆地的发育从属统一的区域动力学环境,主要与滨太平洋构造域的活动和演化息息相关,同时受更广阔的区域地球动力学环境的影响。  相似文献   

青海东昆仑那陵郭勒河东铁矿床磁异常特征分析   总被引：2，自引：1，他引：1  

李洪普 《地质与勘探》2009,45(3):304-311

为了研究那陵郭勒河东铁矿区磁异常源,时该区矿石进行了光谱半定量分析、多项化学分析、组合分析和铁矿物物相分析.对成矿起重要作用的早石炭世灰岩及大理岩、印支期二长花岗岩及黑云母钾长花岗岩、矽卡岩及含矿矽卡岩矿体的磁物性进行了对比分析,对磁异常进行了分析研究,并对矿区磁异常进行了二维反演.结果认为:1、矿石中Fe2O3含量高,大于20%,Tfe含量高达35.86%以上,其中Mfe 28.17%～50.79%,平均35.37%,铁矿石多为原生矿石;2、磁铁矿石磁性强,远高于其它地层、岩体,因此,矿区矿体是引起磁异常的主要因素;3、矿区磁异常的形态、范围及磁异常梯度带与产于矽卡岩内矿体的分布极吻合,本次测制的剖面△T曲线及其二维反演结果也显示,矿区磁异常是由含矿矽卡岩引起的;4、矿区磁异常与磁铁矿体吻合性较好,具有开展磁法工作的良好地球物理前提,下一步深部找矿及外围找矿应安排在磁异常范围内进行.  相似文献   

Recovery scenarios for deep over-exploited aquifers with limited recharge: methodology and application to an aquifer in Belgium   总被引：2，自引：0，他引：2  

M. Van Camp  K. Walraevens 《Environmental Geology》2009,56(8):1505-1516

Recharge of deep-seated aquifers must be provided through leakage from overlying geological formations and can be very limited. Although hydraulic characteristics of these aquifers may be favorable for extensive exploitation, the renewability of the groundwater resource may be very restricted and only significant on long time scales. Over-exploitation of such aquifers leads to steadily declining piezometric levels and water balancing and steady state conditions are not to be expected on the short term. Recovery of such systems is very difficult, also because of the socio-economic dependencies of the water resource and the long time it requires to replenish the system. Management plans for restoration should be based on the transient hydrodynamical behaviour. A recovery plan should be developed based on results of a groundwater flow model. In a first step must be simulated how long it will take for the aquifer system to fully recover by natural recharge. As this will most often be a very long time it can be cancelled out as a realistic scenario. An alternative objective is to be formulated which could be achieved in the near future on a time scale of years or decades. Using model simulations, reduction schemes of exploitation rates shall be quantified that will allow to reach these defined goals, such as raising piezometric levels above the top of the aquifer itself or above the top of the overlying geological unit. The methodology is illustrated with an example of a deep hard rock aquifer in Belgium where piezometric levels have dropped below the top. The objective here was to raise the levels again above the top within the next 50 years. However, this is not accomplished by balancing aquifer recharge and discharge, but is reached by a lateral redistribution of the water over the aquifer extent. A full recovery of this aquifer would require at least a century with only a very limited amount of exploitation.  相似文献   

森林采伐对五营气候的影响     

王淑华  南极月 《黑龙江气象》2008,25(2):5-6

利用五营区森林未开采期1958～1967年的10a与开采后1994～2003年的10a气象资料,1971～1980年森林内（原始林）与森林外（本站）气象资料和1957～2005年五营区汤旺河年最高水位变化情况进行对比分析,得出了森林采伐对五营林区生态环境的影响。  相似文献   

2008年广东“史上最强龙舟水”的气候成因   总被引：8，自引：6，他引：2  

王婷  胡娅敏  潘蔚娟 《广东气象》2008,30(4):5-7

分析了2008年广东“史上最强龙舟水”的气候成因。结果表明：（1）从2007年8月持续到2008年5月的拉尼娜事件,是强降水的主要气候诱因,在其影响下,西太平洋暖池一带热带对流活跃,有利于不稳定能量向北输送;西太平洋副热带高压偏弱、偏东,雨带滞留华南;南海季风爆发偏早、偏强,为强降水提供了丰沛的水汽条件。（2）去冬今春南极海冰面积偏大和青藏高原南部积雪偏少,有利于增强夏季风环流。  相似文献   

A Study of the Teleconnections in the Asian-Pacific Monsoon Region   总被引：2，自引：0，他引：2       下载免费PDF全文

DING Yihui  LIU Yunyun 《Acta Meteorologica Sinica》2008,22(4):404-418

The interactions among the Asian-Pacific monsoon subsystems have significant impacts on the climatic regimes in the monsoon region and even the whole world. Based on the domestic and foreign related research, an analysis is made of four different teleconnection modes found in the Asian-Pacific monsoon region, which reveal clearly the interactions among the Indian summer monsoon （ISM）, the East Asian summer monsoon （EASM）, and the western North Pacific summer monsoon （WNPSM）. The results show that： （1） In the period of the Asian monsoon onset, the date of ISM onset is two weeks earlier than the beginning of the Meiyu over the Yangtze River Basin, and a teleconnection mode is set up from the southwestern India via the Bay of Bengal （BOB） to the Yangtze River Basin and southern Japan, i.e., the ＂southern＂ teleconnection of the Asian summer monsoon. （2） In the Asian monsoon culmination period, the precipitation of the Yangtze River Basin is influenced significantly by the WNPSM through their teleconnection relationship, and is negatively related to the WNPSM rainfall, that is, when the WNPSM is weaker than normal, the precipitation of the Yangtze River Basin is more than normal. （3） In contrast to the rainfall over the Yangtze River Basin, the precipitation of northern China （from the 4th pentad of July to the 3rd pentad of August） is positively related to the WNPSM. When the WNPSM is stronger than normal, the position of the western Pacific subtropical high （WPSH） becomes farther northeast than normal, the anomalous northeastward water vapor transport along the southwestern flank of WPSH is converged over northern China, providing adequate moisture for more rainfalls than normal there. （4） The summer rainfall in northern China has also a positive correlation with the ISM. During the peak period of ISM, a teleconnection pattern is formed from Northwest India via the Tibetan Plateau to northern China, i.e., the ＂northern＂ teleconnection of the Asian summer monsoon. The  相似文献