烟台市海水入侵程度及影响因素探讨

介绍了烟台市开发区夹河地区20年来海水入侵的现状及过程。基于区内4个监测井点的长期观测资料,讨论了影响海水入侵程度的主要因素,认为烟台市海水入侵程度与区内地下水动态关联密切。在海侵区内,地下水被海水浸染的程度主要受地下水位降深控制,地下水降落漏斗范围内海水对地下水浸染程度随水位下降逐年加剧,而漏斗区外地下水质则多年保持相对稳定。     

煤炭三维地震勘探时深转换误差分析及对策

煤炭三维地震勘探对煤层作时深转换时常用的方法是：首先利用钻孔处的目的层铅垂深度除以钻孔处目的层的反射时间值的一半，算出各个钻孔处煤层的大平均速度，然后利用内插法绘制测区速度分布平面图。之后，把速度平面上各点的速度乘以时间平面图上反射时间的一半，得出深度平面图。该时深转换易产生误差，有些情况其误差甚至超过了规范要求。针对测区的实际情况，列举了在二层速度情况下用大平均速度作时深转换时误差分析的一些例子，并提出了如何消除误差的对策。     

西部乡镇国土资源电子政务推广和管理模式

贵州省国土资源厅于2005年6月启动乡镇级电子政务建设。2006年底,开始进入全面推广。由于该方案根据西部乡镇国土资源电子政务工作的特点制定出一套切实可行的管理措施和办法,至2007年4月,遵义县下辖的乡镇电子政务工作已出现前所未有的新局面。该模式充分利用全新的管理平台对各县进行实时监控、交流和管理,效果明显,解决了推广乡镇级电子政务带来问题。本文总结了西部乡镇国土资源电子政务的特点,供大家参考。     

0604号强热带风暴碧利斯对云南的影响及维持机制

应用MICAPS资料及FY-2C卫星云图,通过天气分析与诊断分析,探讨了0604号强热带风暴碧利斯路径西偏南的原因,对造成云南的暴雨过程进行了分析并研究了这次登陆强热带风暴长久维持不消的物理机制。结果表明:黄海副高南落加强西伸与大陆高压合并加强,高压南侧东北风的牵引作用,是"碧利斯"路径西偏南的主要原因;"碧利斯"造成的云南强降水落区分布在热带低压倒槽前东北风急流区内水汽辐合中心区域,并且与700hPa湿Q矢量辐合区对应较好,热带低压影响期间,大气曾具有湿中性垂直运动结构,具备有利于暴雨系统发展的环境条件;"碧利斯"登陆后长时间和一支深厚的西南急流保持联结,是其长久维持不消的主要因素。西南季风云系卷入热带低压,增强了热带低压的水汽和能量输入,是热带低压得以长久维持并造成云南强降水的另一重要原因。南亚高压在热带低压活动期间增强,高层辐散场的增强,低层辐合、高层辐散的结构,与西南急流相联系的垂直正涡度的维持,有利于热带低压的维持,登陆后的热带低压有向高空强辐散区方向移动的趋势。     

奥运气象服务社会经济效益评估个例分析

科学定量地评估2008年北京奥运及演练期间气象信息服务所产生的社会经济效益，是奥运气象服务的一项重要工作，同时也是当前工作中的薄弱环节。在简要评述了近年来有关评估研究工作的基础上，综合应用了社会问卷调查、高端用户深度访谈等定量和定性研究相结合的方法，构建了满意度指数体系，包括：了解和满足用户的需求、预报发布时间和时效、用户对气象服务所产生效益的判断、奥运气象服务手册、用户指南和网站等服务和宣传手段，服务人员能力、针对不同预报要素的预报准确度、用户的未来意向以及对气象部门的整体印象等8类综合指标。首次提出了天气服务用户满意度指数（csiws），并以2006年女垒奥运测试为例进行实证分析，通过数学模型计算了奥组委等高端用户群的满意指数，来定量测量用户群对奥运气象信息服务的期望度和满意度。结果显示，用户对气象部门整体印象最满意，也发现目前奥运气象信息服务中存在的问题和改善的契机，在引导和挖掘用户需求、完善奥运气象宣传手册或用户服务指南以及广为宣传奥运气象官方网站等方面还要下功夫。     

2000年以来云南4次强降雪过程的对比分析

通过对2000年以来云南出现的4次强降雪过程进行分类对比分析和诊断分析, 结果表明:横槽型和北脊南槽型是4次强降雪的主要中高纬环流形势, 3次有南支槽配合, 1次无南支槽活动, 其中2次横槽型造成的强降雪范围广、强度大; 4次强降雪过程云南西侧都有充沛的水汽输送, 水汽通量增大 (即水汽的增加) 是云南强降雪的必备条件, 强降雪出现在较强水汽通量辐合区中, 且落区在辐合中心的偏东一侧、θ_se线陡立区附近以及暖湿不稳定区域; 强降雪在多普勒雷达上显示为20~30 dBz左右的层状云回波, 对流层中下层的高空冷暖平流和高空西南急流是有南支槽影响的强降雪天气的主要大尺度特征, 而低层偏东急流是无南支槽影响的强降雪的主要特征, 因此高低空急流的形成是强降雪的关键。     

Effects of Updated RegCM4 Land Use Data on Near-Surface Temperature Simulation in China

Biogeophysical effects of land use and land cover (LULC) changes play a significant role in modulating climate on various spatial scales. In this study, a set of recent LULC products with a spatial resolution of 500 m was developed in China for update in RegCM4 (regional climate model version 4). Two sets of comparative numerical experiments were conducted to study the effects of LULC changes on near-surface temperature simulation. The results show that after LULC changes, areas of crops and mixed woodlands as well as urban areas increase over entire China, accompanied with greatly expanded mixed farming and forests/field mosaics in southern China, and reduced areas of 1) irrigated crops and short grasses in northern China and the Tibetan Plateau, and 2) semi-desert and desert in northwestern China. Improvements in the LULC data clearly result in more accurate simulations of the near-surface temperature. Specifically, increasing latent heat and longwave albedo due to enhanced LULC in certain areas lead to reduction in land surface temperature (LST), while changes in shortwave albedo and sensible heat also exert a great influence on the LST. Overall, these parameter adjustments reduce the biases in near-surface temperature simulation.     

Evaluation of the Forecast Accuracy of Near-Surface Temperature and Wind in Northwest China Based on the WRF Model

This study investigated the performance of the mesoscale Weather Research and Forecasting (WRF) model in predicting near-surface atmospheric temperature and wind for a complex underlying surface in Northwest China in June and December 2015. The spatial distribution of the monthly average bias errors in the forecasts of 2-m temperature and 10-m wind speed is analyzed first. It is found that the forecast errors for 2-m temperature and 10-m wind speed in June are strongly correlated with the terrain distribution. However, this type of correlation is not apparent in December, perhaps due to the inaccurate specification of the surface albedo and freezing–thawing process of frozen soil in winter in Northwest China in the WRF model. In addition, the WRF model is able to reproduce the diurnal variation in 2-m temperature and 10-m wind speed, although with weakened magnitude. Elevations and land-use types have strong influences on the forecast of near-surface variables with seasonal variations. The overall results imply that accurate specification of the complex underlying surface and seasonal changes in land cover is necessary for improving near-surface forecasts over Northwest China.     

Spatial pattern evolution and casual analysis of county level economy in Changsha-Zhuzhou-Xiangtan urban agglomeration,China

In order to evaluate whether or not the county units＇ economy in the Changsha-Zhuzhou-Xiangtan （Chang-Zhu-Tan） Urban Agglomeration was growing as expected, this study analyzed the spatial economy pattern at county-level by using the Exploratory Spatial Data Analysis （ESDA） method. In this process, the global Moran＇s I and local Getis-Ord Gi＊ indexes were employed to analyze indicators including per capita GDP and three industrials （i.e. primary, secondary and tertiary industry） from 2000 to 2010. The results show that： 1） the county units＇ economy in the Chang-Zhu-Tan Urban Agglomeration has exhibited a strong spatial autocorrelation and an accelerated integration trend since 2008 （Moran＇ s I increased from 0.26 to 0.56）; 2） there is a significant difference in economy development between the northern and southern county units in the Chang-Zhu-Tan Urban Agglomeration： the hotspot zone with high economic level was formed among the northern county units whereas the coldspot zone with low economic level was located in the southern areas. This difference was caused primarily by the increasingly prominent economic radiation effect of Changsha ＇upheaval＇; 3） town density, secondary industry, and the integration policy are the major contributors driving the evolution of the spatial economy pattern in the Chang-Zhu-Tan Urban Agglomeration.     

仪表着陆系统下滑道受遮蔽影响的快速计算

作为飞机进近阶段最依赖的导航设备,仪表着陆系统对电磁环境的变化非常敏感。针对机场运行中最常见的场地保护区入侵问题和违规修建建筑物等情况,提出了下滑道受遮蔽物影响的快速计算方法。结合天线镜像理论和下滑信号空间合成原理,编写了仿真程序。对比实验表明,该快速计算方法能够实现定性分析,可以为机场管理机构和空中交通管理部门提供决策依据。