中国庐山晚第四纪沉积岩系的石英形貌显微结构及环境过程

基于庐山山地晚第四纪地层典型断面的系统调查,从地层剖面层序中筛选的微粒(θ=1～3mm)石英颗粒进行环境电子显微镜观测研究,辨认出显微结构-颗粒形态-变形构造-动力化学作用等特征,运用系统过程发展中的节点事件进行层型剖面的环境响应分析,采取综合指标表征地球表层过程及环境响应情景,明确划分出四个古气候环境发展阶段,由下往上分别表现为冰期环境-间冰期环境-冰缘环境-冰后期环境,为深入研究及科学认识庐山第四纪环境演化过程及全球变化提供了新的基础依据。     

东乌旗查干陶勒盖找矿远景区详查工作浅析

通过研究二连浩特—东乌旗地区高精度航空物探(磁、电、放)资料,圈定具有找矿潜力的重点远景区,然后开展1∶10000面积性地质调查、地面磁法、电法、化探等详查工作,辅以槽探、钻探等工程验证,取得了较好的找矿效果.这种找矿思路以较短的时间、较小的投入而迅速圈定矿产目标,被实践证实是可行、有效的.     

夏季青藏高原大气热源与西南地区东部旱涝的关系

利用1959～2006年西南地区东部20个测站逐日降水量资料和NCEP/NCAR再分析月平均资料,分析了夏季青藏高原大气热源特征,指出了影响西南地区东部夏季旱涝的热源关键区域,并就关键区大气热源对该区域夏季旱涝的影响进行了诊断,得出了以下主要结论:西南地区东部夏季降水与高原主体东南部的热源变化关系密切,当该区域(该区域...     

不同对流层天顶延迟模型在中国西北地区适应性研究

基于Fortran语言对GAMIT10.7软件进行二次开发,实现了Hopfield模型、Saastamoinen模型、Black模型、UNB3模型、EGNOS模型、GPT2w_1+Saastamoinen模型和GPT2w_5+Saastamoinen模型在中国西北地区的对流层延迟解算服务,并分析不同对流层延迟模型在西北地区的适应性问题。实验表明,在实测气象数据模型中,Saastamoinen模型在中国西北地区获取的天顶对流层延迟精度最高,各个测站平均bias值和RMS值分别是-1.67 cm、3.83 cm;Hopfield模型和Black模型精度相当。在非实测气象数据模型中,GPT2w_1+Saastamoinen模型精度最高,GPT2w_5+Saastamoinen模型次之,EGNOS模型最低。不同对流层延迟模型的精度均受季节变化影响,夏季bias的绝对值和RMS值最大,冬季最小,春季和秋季结果相当。     

基于ASTER数据的城市热环境遥感监测研究

以ASTER数据为数据源,采用同一颗卫星上的MODIS数据得到大气透过率;利用可见光和近红外波段对下垫面类型进行分类和利用JPL(Jet Propulsion Lab)提供的光谱库计算地表比辐射率,进而采用劈窗算法进行地表温度(Land Surface Temperature,LST)的反演。在此基础上,利用反演的LST、分类结果和归一化差值植被指数(NDVI),对沧州地区的城市热环境进行了定量分析,研究结果可为进一步深入探讨城市热岛的发生发展规律以及城市热环境的模拟调控、优化布局提供一定的科学依据。     

海洋测深中的船移效应研究

海洋测深大多是在移动的测量船上进行的,测量船的移动则不可避免地产生船移效应,因而船移效应是影响海洋测深精度的因素之一。在系统推证海洋测深中的船移效应模型基础上,对几种典型船速、水深、海底坡度和波束角情形下的船移效应进行了数值计算,研究了船移效应的影响规律和量级,揭示了船移效应的非对称性影响。根据海洋测深的IHO最低标准要求,提出了采用窄波束和限制船速的降低测深船移效应影响的有效方法。     

Assessment of Erythemal UV Level in Nepal Based on Solar UV Estimates from Total Ozone Mapping Spectrometer

Nepal lies on the southern slope of Himalaya in Asia. In a width ranging between 150 and 250 km, the altitude varies greatly from about 100 m at its southern border to a maximum of 8848 min the northern part. Like the variation in altitude, climatic condition varies quite a lot. Long-term monthly mean erythemal UV daily dose values for Nepal are evaluated using Total Ozone Mapping Spectrometer (TOMS) estimation from the time of its overpass between 1996 and 2003. The results are presented as summer and winter maps of mean UV levels in each satellite grid. The mean winter erythemal UV daily dose ranges between 2.1 and 3.6 kJ m-2 whereas summer values are found to lie between 4.6 and 9.7 kJ m-2. The altitude variation increases the UV levels by about 0.2 kJ km-1 in winter months, and 0.9 kJ km-1 in summer. A multiyear monthly average erythemal daily dose in most of the areas shows that the summer value is about three times higher than that in winter. Although year-to-year variation is not pronounced in high- and mid-elevation regions, UV levels seemed to decrease from 1997 to 2002 in the southern part of the country in the low elevation region by about 5.35%. Due to the combined effects of the altitude, low ozone concentration in the troposphere, and thin air, surface UV radiation at higher altitudes is found to be higher than in the surrounding regions.     

Water Vapor and Cloud Radiative Forcings over the Pacific Ocean Simulated by the LASG/IAP AGCM: Sensitivity to Convection Schemes

Characteristics of the total clear-sky greenhouse effect (GA) and cloud radiative forcings (CRFs), along with the radiative-related water vapor and cloud properties simulated by the Spectral Atmospheric Model developed by LASGIAP (SAMIL) are evaluated. Impacts of the convection scheme on the simulation of CRFs are discussed by using two AMIP (Atmospheric Model Inter-comparison Project) type simulations employing different convection schemes: the new Zhang-McFarlane (NZH) and Tiedtke (TDK) convection schemes. It shows that both the climatological GA and its response to El Nio warming are simulated well, both in terms of spatial pattern and magnitude. The impact of the convection scheme on GA is not significant. The climatological longwave CRF (LWCRF) and its response to El Nio warming are simulated well, but with a prominently weaker magnitude. The simulation of the climatology (response) of LWCRF in the NZH (TDK) run is slightly more realistic than in the TDK (NZH) simulation, indicating significant impacts of the convection scheme. The shortwave CRF (SWCRF) shows large biases in both spatial pattern and magnitude, and the results from the TDK run are better than those from the NZH run. A spuriously excessive negative climatological SWCRF over the southeastern Pacific and an insufficient response of SWCRF to El Nio warming over the tropical Pacific are seen in the NZH run. These two biases are alleviated in the TDK run, since it produces vigorous convection, which is related to the low threshold for convection to take place. Also, impacts of the convection scheme on the cloud profile are discussed.     

基于“.NET”的华南区域人工增雨效果统计检验共享平台的设计与实现

利用Google Earth二次开发工具API设计了一种基于浏览器/服务器(B/S)模式的人工增雨作业效果检验的动态人工增雨效果检验共享系统。该系统基于“.NET”平台,以C#作为主要开发语言,利用Google Earth二次开发工具API实现了区域级人工增雨作业效果评估的共享,实现了Google Map和火箭作业点、...     

新疆“2.28” 大风的中尺度数值模拟

受西西伯利亚较强冷空气入侵的影响,2007年2月28日02时,乌鲁木齐开往阿克苏的5807次旅客列车,在新疆三十里风区遭遇狂风,造成11节车厢脱轨侧翻。使用WRF模式对这次大风天气过程进行了数值模拟。结果表明：WRF模式较好地模拟了三十里风区大风的演变和分布特征,对逐时风速的模拟较实况偏小,但变化比较同步;很大的气压梯度和特殊的地形是大风形成的主要原因,狭管效应和下坡风同时存在。