A sensitivity of squall-line intensity to environmental static stability under various shear and moisture conditions

Squall lines develop in various climate regions having diverse environmental profiles of wind shear, moisture, and temperature. In order to explore the sensitivity of squall lines to these environmental profiles, we have performed an extensive set of numerical simulations under various shear and moisture conditions in midlatitude-continental and tropical–oceanic temperature environments. From the results of the sensitivity simulations and the analyses of the environmental parameters, it is found that the static stability in a convectively unstable layer is of primary importance in determining the strength of squall lines. Under temperature environments having the same static stability, convective available potential energy (CAPE) and precipitable water content (PWC) well describe the squall-line intensity. Vertical shear also plays an important role in determining the squall-line structure as well as the intensity through the interaction with surface cold pool. The combination of the static stability in a convectively unstable layer, CAPE, and PWC should be examined in diagnosing the intensity of squall lines that develop with an optimal shear for their environment.     

论层序地层学与含油气系统在油气勘探中的联系——以鄂尔多斯中生代盆地为例

虽然层序地层学与含油气系统理论的各自研究对象和研究方法不同，但由于层序地层学研究对象(沉积岩)是含油气系统研究对象(油气)的载体，二者可以由含油气盆地分析有机的结合起来。层序地层分析包含了对含油气系统的地质要素及成藏作用载体的分析，因而沉积层序的组成单元与含油气系统的地质要素有必然的联系：在一个沉积盆地的数个沉积层序中，成熟烃源岩往往是地史中具一定埋深、分布广、厚度大、有机质含量高的凝缩层，这个凝缩层往往是一个构造超层序的最大海(湖)泛面；储集岩往往是成熟烃源岩之上层序的低水位体系域或紧邻成熟烃源岩的高水位体系域；有效盖层为储集岩之上层序的水进体系域及凝缩层；成熟烃源岩之上的沉积层序为上覆岩层；低水位体系域储集岩有可能沿上倾方向尖灭，被层序界面及其上层序的水进体系域岩性圈闭；除构造裂缝外，低水位体系域下切谷可作为油气向上运移通道；一个含油气系统往往跨越不同的沉积层序甚至构造超层序。     

泉州市地震应急与救援工作体系的建设

本文简要介绍泉州市地震局依靠各级政府、有关部门和全社会的共同努力 ,以落实地震应急预案为楔机促进“预、防、救”三大体系工全面发展的工作经验 :一、以落实《地震应急预案》为抓手 ,争取项目 ,以项目带动一切 ;二、结合社会转型全面加大防震减灾知识宣传力度 ;三、不以经费的来源划分你我 ,动员全社会的力量建立健全预警应急机制。     

中晚全新世科尔沁沙地演化与气候变化

科尔沁沙地位于东亚季风区的东北缘,环境对气候变化反应非常敏感。地层沉积相、粒度与地球化学参数表明中晚全新世科尔沁沙地环境与气候变化可以分为以下3个阶段：7.0~3.6 cal ka BP,沙地逐渐固定、缩小,冬季风减弱,夏季风不断增强,气候趋于暖湿;3.6~1.3 cal ka BP,沙地总体上较为稳定,但也存在活化、扩张,与上一阶段相比夏季风强度有所降低,但仍强于冬季风,气候相对暖湿;1.3~0.65 cal ka BP,沙地出现多次活化、扩张和固定、缩小,冬夏季风交替频繁,气候呈现冷干-相对暖湿的组合。具体来讲,中晚全新世以来科尔沁沙地存在8次活化、扩张和8次固定、缩小期,气候变化也存在8次冷干和8次相对暖湿期,两者存在明显的对应关系。太阳辐射与全球冰量变化是中晚全新世科尔沁沙地演化与气候格局的主要驱动力。     

Decision-support systems for groundwater protection: innovative tools for resource management

Governmental authorities are forced by law to make decisions within the framework of European, national and regional directives in the fields of spatial planning, groundwater and environmental protection. These tasks can be supported by a decision-support system, which integrates data from various sources and helps to make decision processes more effective and transparent. Basic work for such a decision support system has been done in a transnational and interdisciplinary project (Interreg II C: KATER), including metadata definition, metadata system, cartographic tools and GIS tools. The direct integration of these tools and information in the decision process will be implemented in the next few years (project KATER II).     

江苏省国土资源基础数据整合技术研究与实践

本文结合《江苏省国土资源基础数据库建设试点》项目,开展国土资源基础数据库整合关键技术的研究。文中介绍了整合技术的总体思路和数据整合关键技术研究成果,以及成果应用效果,为国土资源行业开展类似工作提供一些实践经验参考。     

复杂地形区陆面资料对WRF模式模拟性能的影响

本文利用WRF（Weather Research and Forecasting）模式耦合Noah陆面过程模式,对比研究了使用不同精度陆面资料:WRF默认陆面资料、中国1 km分辨率数字高程模型数据集、2006年MODIS（MODerate-resolution Imaging Spectroradiometer）土地利用和植被覆盖度资料,WRF模式对兰州地区冬季气象场模拟结果的差异。结果表明,近地面气温对陆面资料的精度非常敏感,而风场对陆面资料的精度不敏感,WRF模式对气温的模拟效果好于对风场模拟。采用高精度且时效性好的陆面资料后,WRF模拟的近地面气温准确率提高了15.8%,模拟的夜间气温改进幅度较白天大。陆面资料可影响整个边界层温度场分布,准确的陆面资料对提高WRF模式模拟近地面乃至整个边界层气象场至关重要。尽管风速模拟误差较大,但总体上WRF模式能较准确地模拟出研究区的风场演变特征。使用新的陆面资料后WRF模拟的风速误差略有减小,风向误差略有增加。干旱半干旱区冬季数值模拟需要注意土壤湿度初值和模式初始积分时刻对模拟结果的影响。     

湿斜压大气中暴雨中尺度系统发展的一种可能机制

根据暴雨中尺度系统发生时的大气运动特征,在绝热、无摩擦条件下,从湿斜压原始方程出发,考虑大气运动的涡度及散度演化不仅受动力场的制约,而且还受到热力场的约束,采用不同于传统研究涡度及散度方程的分析方法,导出了新形式的涡度及散度方程。在此基础上,分析了湿斜压大气中对流层中低层气流旋转与辐合持续增长的动力特征,初步揭示了湿斜压大气中暴雨中尺度系统发展的动力机制。     

Laboratory and field investigations of rockburst phenomena using concurrent geotomographic imaging and acoustic emission/microseismic techniques

The progress made on three phases of a research project, started in 1986 to investigate mining induced seismicity/rockburst phenomena using concurrent geotomographic imaging and microseismic monitoring techniques, is described. Phase I is the geotomographic software development and laboratory calibration trials. Phase II is the enhancement of traditional microseismic monitoring instrumentation with a waveform acquisition system, so that source mechanism studies can be carried out on mining induced seismic events. Phase III is the field trials of the hybrid technique which will be used to monitor changing rock mass physical properties, in response to mining. Preliminary results from all three phases are given, together with an outline of current and future research planned.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal 1987.     

300 BC-1900 AD无定河流域城镇时空格局演变

通过分析和整理从战国中晚期（约300 BC）至清末（约1900 AD）无定河流域历代县级及以上城址的位置、兴废年代数据,结合行政区划沿革、经济社会发展、政权更迭等资料,分析流域城镇格局的时空演变过程。研究表明：① 受气候周期性波动影响,无定河流域城镇的兴起与衰废具有明显的周期性特征,城镇几何中心的移动轨迹具有明显的“西北—东南”向潮汐性运动特征;② 城址存续年限普遍较短,具有明显的阶段性特征,流域内曾存在过4个阶段性中心城镇,中心城镇移动的方向和过程与城镇几何中心的潮汐性移动过程趋势一致;③ 流域城镇空间格局可分为3种类型,即秦汉与隋唐时期的沿河流谷地分布,宋、明两代的沿边境线与长城分布,以及元、清两代集中于流域下游分布。流域城镇未来的发展布局应重视气候变化对城镇分布的长期影响,关注区域环境的脆弱性,合理安排城镇体系发展规模与布局。