CMIP3与CMIP5模式对中国西北干旱区气温和降水的模拟能力比较

通过对15组CMIP3和CMIP5两代模式集合平均对中国西北干旱区气温和降水的模拟能力比较,发现CMIP5模式对气温和降水的模拟更接近观测值。CMIP5模式模拟年、春季、夏季、秋季平均气温的相关系数比CMIP3模式分别提升了0.15、0.13、0.24和0.02,冬季下降了0.07。CMIP5模式对西北干旱区的平均气温变化趋势的模拟效果比CMIP3有所提高,对年、春季、夏季、秋季、冬季趋势的模拟偏差比CMIP3分别减少了0.03℃/10a、0.10℃/10a、0.01℃/10a、0.06℃/10a、0.14℃/10a。对西北干旱区平均气温年、季的模拟偏差分布上,CMIP5模式的偏差均比CMIP3低1~2℃。但是天山区年、季节平均气温的模拟与整体模拟偏低情况相反,CMIP3和CMIP5分别偏高3~6℃和1~4℃,对夏季的模拟偏高最严重,分别达到6℃和4℃。CMIP5模式整体对西北干旱区降水量的模拟结果与观测值的平均相关系数与CMIP3相差不大,均不超过0.1,而且偏差仍然较大。CMIP5模式对西北干旱区的降水量的变化趋势模拟效果比CMIP3有所降低,对年、春季、夏季、秋季、冬季趋势的模拟偏差比CMIP3增加了0.67 mm/10a、0.23 mm/10a、0.51 mm/10a、0.11 mm/10a、0.14 mm/10a。CMIP5模式对年、春季、夏季、秋季和冬季的降水量模拟的均方根误差相比CMIP3分别减少77.6 mm、25.5 mm、25.0 mm、18.8 mm和13.9 mm。在空间上,CMIP5模式对年、季节降水模拟仍然偏高,但是比CMIP3有明显缓解;CMIP3和CMIP5模式对夏季天山区年降水量和夏季降水量的模拟也与大部分区域偏高的趋势明显相反,两代模式对夏季天山区的降水模拟均偏低50 mm左右。     

一次暴雨过程多普勒天气雷达风场资料分析

通过对１９９御７月１４日的大－暴雨天气过程所获取的３８２４多普勒天气雷达平均径向风场资料的分析，发现边界层急流与较强的降水相伴。表明多普勒天气雷达对中小尺度天气系统和灾害性天气预报有预警作用。     

基于相对风险模型的土地利用变化生态风险定量评价——以石羊河流域为例

土地利用是否合理是推进国民经济发展的关键,也是生态环境变化的风向标。通过理论研究和实地调研,构建了土地利用生态风险定量评价体系,借助相对风险模型（RRM）对石羊河流域的生态风险及其影响因素进行研究。结果表明：（1）在划分的3个评价单元中,中部绿洲生态保护区在土地利用中面临的生态风险最大,北部盆地防沙治沙区次之,南部山地水源涵养区生态风险最小;（2）在3大风险单元的6类不同风险源中,工程建设对石羊河流域的生态风险影响最大,其次是作物种植和畜牧养殖,且在自然环境相对较好的区域表现得尤为明显。     

旋转电极法研究盐类溶解─LiCl、NaCl、KCl在水中的溶解动力学

利用旋转盘装置结合离子选择电极研究了ＬｉＣｌ、ＮａＣｌ、ＫＣｌ在２０℃～３５℃水中溶解动力学，得到了溶解动力学方程．     

淮南矿区煤矸石的物质组成特征及资源化评价

本文利用各种测试方法,对淮南谢桥、新庄孜和张集煤矿采集的不同层位来源的240个煤矸石样品的化学成分、矿物成分和微量元素的进行测试与分析,得出了淮南矿区不同煤矿煤矸石的化学成分特征及其中微量元素的含量变化,评价了煤矸石中有害元素的环境影响作用。结合煤矸石基本特征,提出了合理的资源化利用途径,为煤矿开采过程的主要固体废物煤矸石综合利用和资源化、煤矿环境保护提供了参考资料。     

The Evolutionary History of Ore-forming Processes of Metallic Ore Deposits in Northern Guangxi1

Abstract The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis shows features of polycyclic spiral evolution throughout the geological history. As far as various cycles are concerned, mantle-derived ore substances were reduced while crust-derived ore substances increased from early to late times; in the whole geological evolutionary history, mantle-derived substances decreased gradually while crust-derived ones increased. Meanwhile ore element associations became more and more varied. In terms of space, mineralization migrated from the old basement outwards, i.e. from west to east during the Precambrian, and from north to south during the Phanerozoic, and again from east to west during the Yanshanian.     

Observation and study on the whole process of cloud-to-ground lightning using narrowband radio interferometer

A narrowband radio interferometer has been developed and used to locate the entire sources of VHF radiations from a negative cloud-to-ground (CG) lightning discharge which contains 19 strokes. This system uses five antennas to form an array consisting of short- and long-baselines along two or- thogonal directions. The system error which comes from frequency conversion is reduced by phase detection through direct high frequency amplifying. An interactive graphic analysis procedure is used to remove the fringe ambiguities which exist inherently in interferometry and to determine the direction of lightning radiation sources in two dimensions (azimuth and elevation) as a function of time at a time resolution of microsecond orders. With the developed system, the whole progression process in time and space of a lightning flash can be reconstructed. In this paper, combining the synchronous data of electric filed change and VHF radiation, the whole processes of an example negative CG flash have been studied in detail. It is found that the preliminary breakdown event of the CG flash started from negative charge region and exhibited firstly a downward pregression and then an upward propagation. There were very intense and continuous radiations during stepped leaders which became much stronger when the first return stroke began. In contrast, there were less and only discrete radiations during dart leaders. Stepped leader and dart leader may transform to each other depending on the state of the ionization of the path. The progression speed of initial stepped leaders was about 105 ms?1, while that was about 4.1×106 and 6.0×106 ms?1 for dart leaders and dart-stepped leaders, respectively. M events produced hook-shaped field changes accompanied by active burst of radiations at their begin- nings. Followed these active radiation processes, M events appeared to contact finally into conducting main discharge channels. The mean progression speed of M events was about 7×107 ms?1, greater than that of the dart leaders and dart-step leaders. K events and attempted leaders were essentially the same as dart leaders except that they could not reach the ground and initiate return strokes.     

全国自动地震速报系统综合评估

通过对2011年1月1日至12月31日的3套独立自动地震定位系统结果进行综合处理,得出中国自动地震综合目录,并与正式速报结果进行对比,得出全国自动地震速报系统综合评估结果,发现该目录对于国内绝大部分5级以上、国外7级以上地震实现整体覆盖,且没有误报发生,可以作为国家台网中心正式地震速报的重要参考,对于建立“自动报～正式报”的两级地震速报制度可提供技术支撑。     

长株潭城市群耕地动态变化及驱动力实证研究

利用长株潭城市群近10年的土地利用调查数据及相关社会经济资料,宏观分析了该区域耕地动态变化的趋势,并用主成分分析和多元逐步回归分析法探讨了耕地数量变化的主要驱动力。结果表明,长株潭城市群耕地资源的时空变化特征显著,耕地呈现出逐年减少的总体趋势;得出社会发展因素、经济增长因素、农业科技水平的提高因素以及国家的相关政策是长株潭城市群耕地资源变化的四大类主要驱动因素;总体上,耕地面积与社会经济发展各因素间的相关系数约低于累计耕地面积与各因素之间的相关系数,说明该区域耕地减少与社会经济发展存在时间上的错位性,即经济和社会发展滞后于对耕地资源的占用。     

A Coal Burst Risk Assessment Model of Seismic Events Based on Multiple Seismic Source Parameters: A Case Study of the Huating Coal Mine,Gansu Province,China

Mining-induced tremors are indispensable events that gestate and trigger coal bursts. The radiated energy is usually considered a key index to assess coal burst risk of seismic events. This paper presents a model to assess coal burst risk of seismic events based on multiple seismic source parameters. By considering the distribution and relation laws of the seismic source parameters of coal bursts, the model aims to identify dangerous seismic events that more closely match the characteristics of multiple seismic source parameters of coal bursts. The new coal burst risk index T is proposed. It consists of the similarity index SI (representing the similarity degree of relations between seismic events and coal burst events based on seismic source parameters) and the strength index ST (representing the burst strength of seismic events). We studied 79 coal burst events that occurred during extraction in LW250105 of the Huating coal mine in Gansu Province, China. We obtained the distribution and relation laws of multiple seismic source parameters of coal burst events to establish SI and ST. Two groups of seismic events with different energy distributions were examined to compare the assessment results based on the new model and energy criteria. The results show that 80% and 89% of seismic events with strong coal burst risk in Groups A and B, respectively, were coincident, and the seismic events with medium coal burst risk were slightly less compared to those based on radiated energy. The results indicate that the assessment based on the T value is a modification and optimization of that based on radiated energy. This model is conducive to improving the efficiency of monitoring and early warning of coal burst risk.