The impact of atmospheric heat sources over the eastern Tibetan Plateau and the tropical western Pacific on the summer rainfall over the Yangtze-River basin   总被引：9，自引：0，他引：9  

简茂球  乔云亭  袁卓建  罗会邦 《大气科学进展》2006,23(1):149-155

The variability of the summer rainfall over China is analyzed using the EOF procedure with a new parameter （namely, mode station variance percentage） based on 1951-2000 summer rainfall data from 160 stations in China. Compared with mode variance friction, the mode station variance percentage not only reveals more localized characteristics of the variability of the summer rainfall, but also helps to distinguish the regions with a high degree of dominant EOF modes representing the analyzed observational variable. The atmospheric circulation diagnostic studies with the NCEP/NCAR reanalysis daily data from 1966 to 2000 show that in summer, abundant （scarce） rainfall in the belt-area from the upper-middle reaches of the Yangtze River northeastward to the Huaihe River basin is linked to strong （weak） heat sources over the eastern Tibetan Plateau, while the abundant （scarce） rainfall in the area to the south of the middle-lower reaches of the Yangtze River is closely linked to the weak （strong） heat sources over the tropical western Pacific.  相似文献   

Wind-driven, double-gyre, ocean circulation in a reduced-gravity, 2.5-layer, lattice boltzmann model     

钟霖浩  冯士德  罗德海  高守亭 《大气科学进展》2006,23(4):561-578

A coupled lattice Boltzmann （LB） model with second-order accuracy is applied to the reduced-gravity, shallow water, 2.5-layer model for wind-driven double-gyre ocean circulation. By introducing the secondorder integral approximation for the collision operator, the model becomes fully explicit. The Coriolis force and other external forces are included in the model with second-order accuracy, which is consistent with the discretization accuracy of the LB equation. The feature of the multiple equilibria solutions is found in the numerical experiments under different Reynolds numbers based on this LB scheme. With the Reynolds number increasing from 3000 to 4000, the solution of this model is destabilized from the anti-symmetric double-gyre solution to the subtropic gyre solution and then to the subpolar gyre solution. The transitions between these equilibria states are also found in some parameter ranges. The time-dependent variability of the circulation based on this LB simulation is also discussed for varying viscosity regimes. The flow of this model exhibits oscillations with different timescales varying from subannual to interannual. The corresponding statistical oscillation modes are obtained by spectral analysis. By analyzing the spatiotemporal structures of these modes, it is found that the subannual oscillation with a 9-month period originates from the barotropic Rossby basin mode, and the interarmual oscillations with periods ranging from 1.5 years to 4.6 years originate from the recirculation gyre modes, which include the barotropic and the baroclinic recirculation gyre modes.  相似文献   

Boundary-layer wind structure in a landfalling tropical cyclone   总被引：1，自引：0，他引：1  

唐晓东  谈哲敏 《大气科学进展》2006,23(5):737-749

In this study, a slab boundary layer model with a constant depth is used to analyze the boundary-layer wind structure in a landfalling tropical cyclone. Asymmetry is found in both the tangential and radial components of horizontal wind in the tropical cyclone boundary layer at landfall. For a steady tropical cyclone on a straight coastline at landfall, the magnitude of the radial component is greater in the offshoreflow side and the tangential component is greater over the sea, slightly offshore, therefore the greater total wind speed occurs in the offshore-flow side over the sea. The budget analysis suggests that： （1） a greater surface friction over land produces a greater inflow and the nonlinear effect advects the maximum inflow downstream, and （2） a smaller surface friction over the sea makes the decrease of the tangential wind component less than that over land. Moreover, the boundary layer wind structures in a tropical cyclone are related to the locations of the tropical cyclone relative to the coastline due to the different surface frictions. During tropical cyclone landfall, the impact of rough terrain on the cyclone increases, so the magnitude of the radial component of wind speed increases in the offshore-flow side and the tangential component outside the radius of maximum wind speed decreases gradually.  相似文献   

环境与工程地球物理的发展趋势   总被引：19，自引：16，他引：3       下载免费PDF全文

胡祥云  杨迪坤  刘少华  胡正旺 《地球物理学进展》2006,21(2):598-604

2006年6月在武汉召开了第二届环境与工程地球物理国际会议.会议围绕近年来兴起的近地表探测问题展开,涉及方法原理、仪器采集、资料处理等各个环节,反映出国内外环境与工程探测领域的若干前沿热点和发展动态.结合本次会议,可以看出该学科主要趋势为：应用领域不断扩宽,方法技术灵活多样,重视基础理论研究,开发新型（特种）仪器,通过高精度测量、延时测量、先进的数据处理技术和信息技术等手段改善探测质量.我国对环境与工程地球物理有很大的需要,应根据我国实际情况,吸收国外先进经验,积极开展自主创新.  相似文献   

CSAMT的静态效应校正及应用   总被引：7，自引：2，他引：5       下载免费PDF全文

黄兆辉  底青云  侯胜利 《地球物理学进展》2006,21(4):1290-1295

CSAMT方法在地下近地表存在电性横向不均匀时,在双对数坐标系中视电阻率曲线会出现沿着视电阻率轴平行移动的现象,称之为静态效应.静态效应对深部电性结构处理解释结果影响重大,需对其进行合适的校正.本文介绍了目前通常使用的几种静态校正方法,并且分析了各方法的优缺点.在新疆某地进行的CSAMT铜矿勘探中,应用了曲线平移法进行静态校正,取得了较好的效果.  相似文献   

农用地分等成果在土地利用总体规划中的应用   总被引：10，自引：1，他引：9  

杨建波  王国强  王莉  胡纪鹏 《地域研究与开发》2006,25(6):118-121

不同层次的农用地分等成果有着不同的应用方向。文章以土地利用总体规划为导向,以农用地利用等别与自然等别的高低延伸顺序与耕地最低需求量相结合,确定出基本农田保护的数量;以基本农田数量的105％～110％为基准,将县级利用等别图与自然等别图重叠的区域划定为基本农田保护区;交叉运用分等的土壤肥力图、气候生产潜力指数曲线图来选择作物适宜生长区和改良土地用养结构;以分等因素图作为限制因子的选择标准来划分土地限制类别区。  相似文献   

VPN技术在防震减灾中的应用   总被引：2，自引：2，他引：0  

邹振轩 《地震地磁观测与研究》2006,27(1):79-83

简要介绍VPN技术的应用、原理与搭建,并介绍了两个应用实例。显示了VPN技术在防震减灾工作中有广阔的应用前景。  相似文献   

城市活断层地震勘探的最佳组合方法与应用研究   总被引：15，自引：4，他引：11       下载免费PDF全文

方盛明  张先康  刘保金  段永红  徐锡伟  张永超 《地震地质》2006,28(4):646-654

根据近年来在全国开展的大城市活断层地震探测实践,在简要介绍各种地震勘探方法的基本原理和工作方法的基础上,着重分析了不同地震勘探方法的适用范围、获得的主要成果和所解决的主要问题。讨论了现阶段用地震勘探获取地壳结构和对不同深度断层定位的最佳组合方法,即对于有沉积覆盖的隐伏数百米深度至地表的断层,可用浅层地震勘探对其进行追踪,基底(埋深数公里)以上断层可采用高分辨地震折射探测;对于地壳中、深断裂应用反射地震勘探和深地震宽角反射/折射联合探测方法;还可以进一步采用三维深地震测深方法获得城市下方的三维结构和构造信息。采用这样的组合探测方法能够较好地获得断层在不同深度的产状与展布以及由深至浅完整的分布图像,并给出了应用实例  相似文献   

抢抓机遇锐意进取推进我省气象事业再上新台阶——2006年全省气象工作会议工作报告     

秦元明 《吉林气象》2006,(1):4-13

“十五”是不平凡的五年。在党的十六大精神指引下,在中国气象局和省委、省政府的正确领导下,全省气象干部职工深入落实科学发展观,认真贯彻落实中国气象事业发展战略研究成果,坚持把发展作为第一要务,大力实施“三大战略”,气象服务工作、现代化建设、改革开放和精神文明建设都取得了重大成就。  相似文献   

基于数字航摄影像成大比例尺地形图技术方法研究     

齐心  礼盛东  王果隆  张海泉 《测绘与空间地理信息》2007,30(3):6-11

结合苏州市1∶1000地形图测绘项目,进行DMC数码航摄仪数字影像成大比例尺地形图试验研究,分析、确定DMC数字影像成大比例尺地形图的技术方法,明确外业布点方案,分析成图的平面、高程精度,为今后制定数字摄影影像成大比例尺地形图技术标准提供参考依据。  相似文献