鼎湖山森林地区臭氧及其前体物的变化特征和分析   总被引：18，自引：2，他引：16  

白建辉  徐永福  陈辉  王庚辰  石立庆  孟泽  黄忠良  孔国辉 《气候与环境研究》2003,8(3):370-380

通过对鼎湖山森林地区近地面O3和NOx浓度、太阳辐射、气象参数等为期一年的观测和资料分析,给出了地面O3和NOx浓度、太阳辐射的变化规律及其相互之间的关系.地面O3、NOx、CO、SO2浓度以及紫外辐射、太阳总辐射等有明显的日变化和季节变化.不同因子对O3的敏感性试验结果表明,晴天和实际天气,O3浓度对NO、NO2浓度的变化最为敏感,其次是水汽、气溶胶,最后是紫外辐射.所有因子的变化均引起O3在湿季比干季更大的变化率,因此在研究臭氧化学和光化学时,应该考虑水汽以及OH自由基的重要作用.对于晴天和实际天气的逐时值和日平均值而言,O3浓度与NO2/NO之间存在很好的正相关关系,比值NO2/NO可以作为判断O3峰值出现的一个指标.O3极值的出现既受NO和NOx影响,也受气象因素(温湿度、云、风、雾、降雨)和辐射的影响.周末O3、NOx浓度及NO2/NO有规律的增大,表明实验地点的大气受到人为污染源的影响.  相似文献   

地震预警系统的“盲区”控制问题——以首都圈地震预警原型系统为例     

李佳威  吴忠良 《中国地震》2016,32(4):584-594

以首都圈地震预警原型系统为例,讨论了地震早期预警系统(EEWS)设计中如何通过对"盲区"的控制达到最大限度减轻地震灾害损失的目的,认为如果不仅考虑走时,而且考虑有限震源尺度和记录台站的实际工作状况,那么在台间距为20km时继续加密台站,虽不再能明显减小"盲区",却仍可以对控制"盲区"、提高预警系统的减灾效能发挥重要作用。  相似文献   

Inter-annual variations in vegetation and their response to climatic factors in the upper catchments of the Yellow River from 2000 to 2010   总被引：1，自引：0，他引：1  

Ran Cao  Weiguo Jiang  Lihua Yuan  Wenjie Wang  Zhongliang Lv  Zheng Chen 《地理学报(英文版)》2014,24(6):963-979

To understand the variations in vegetation and their correlation with climate factors in the upper catchments of the Yellow River, China, Normalized Difference Vegetation Index（NDVI） time series data from 2000 to 2010 were collected based on the MOD13Q1 product. The coefficient of variation, Theil–Sen median trend analysis and the Mann–Kendall test were combined to investigate the volatility characteristic and trend characteristic of the vegetation. Climate data sets were then used to analyze the correlation between variations in vegetation and climate change. In terms of the temporal variations, the vegetation in this study area improved slightly from 2000 to 2010, although the volatility characteristic was larger in 2000–2005 than in 2006–2010. In terms of the spatial variation, vegetation which is relatively stable and has a significantly increasing trend accounts for the largest part of the study area. Its spatial distribution is highly correlated with altitude, which ranges from about 2000 to 3000 m in this area. Highly fluctuating vegetation and vegetation which showed a significantly decreasing trend were mostly distributed around the reservoirs and in the reaches of the river with hydropower developments. Vegetation with a relatively stable and significantly decreasing trend and vegetation with a highly fluctuating and significantly increasing trend are widely dispersed. With respect to the response of vegetation to climate change, about 20–30% of the vegetation has a significant correlation with climatic factors and the correlations in most areas are positive： regions with precipitation as the key influencing factor account for more than 10% of the area; regions with temperature as the key influencing factor account for less than 10% of the area; and regions with precipitation and temperature as the key influencing factors together account for about 5% of the total area. More than 70% of the vegetation has an insignificant correlation with climatic factors.  相似文献   

地理信息系统专业实验课程的优化设计     

蔡忠亮  李小欢  谢彩云  杜清运 《测绘通报》2015,(7):124-127

分析了目前地理信息系统(GIS)专业实验课程的特点及存在问题,并在充分考虑实验课程的关系、内容衔接及课程发展等问题的基础上,根据GIS人才培养需求及专业发展特点,对本专业实验课程体系进行了优化设计,并对相应实验课程内容进行了调整。以武汉大学GIS专业的实验课程为例,研究了实验课程的优化设计方案。该研究成果被应用到2013 GIS专业培养方案设计工作中。  相似文献   

A new marine controlled‐source electromagnetic receiver with an acoustic telemetry modem and arm‐folding mechanism          下载免费PDF全文

Chen Kai  Wei Wenbo  Deng Ming  Wu Zhongliang  Yu Gang 《Geophysical Prospecting》2015,63(6):1420-1429

We developed a new marine controlled‐source electromagnetic receiver for detecting methane hydrate zones and oil and gas reservoirs on the seafloor, which is not imaged well by seismic reflection surveys. To determine the seafloor structure, the electromagnetic receiver should have low noise, power consumption, clock drift error, and operating costs while being highly reliable. Because no suitable receiver was available in our laboratory, we developed a new marine controlled‐source electromagnetic receiver with these characteristics; the receiver is equipped with acoustic telemetry modem and an arm‐folding mechanism to facilitate deployment and recovering operations. To demonstrate the applicability of our new receiver, we carried out a field experiment offshore of Guangzhou in the South China Sea, where methane hydrates have been discovered. We successfully obtained controlled‐source electromagnetic data along a profile about 13 km long. All six new receivers were recovered, and high‐quality electromagnetic data were obtained. Relatively high apparent resistivity values were detected. The results of the offshore field experiment support the claim that the electromagnetic data obtained using the new receiver are of sufficient quality for the survey target.  相似文献   

2008年6-8月河南空中云水资源分布特征     

孙仲毅  靳冰凌  王敏  孙日丁  邢用书  芦阿咪  李忠亮  职青   《气象与环境科学》2009,32(4):55-59

利用FY2号卫星观测的2008年6-8月OLR资料和T213提供的相对湿度资料,分析了2008年夏季(6-8月)河南空中云系特征和水汽的空间分布,结果表明:实时OLR产品图像可以作为一幅天气图,进行数值化分析和处理.OLR值可以反映中高纬地区对流活动的强弱.2008年夏季,OLR的月平均分布与夏季月总降水量有较好的对应关系;相对湿度月平均分布与河南省月降水量趋势基本一致.  相似文献   

A Framework of Massively Parallel Analysis of Regional Earthquake Activities     

ZHANG Huai  SHI Yaolin  WU Zhongliang Graduate University of Chinese Academy of Sciences  Beijing  China Institute of Geophysics  China Earthquake Administration  Beijing  China 《《地质学报》英文版》2009,83(4)

Recent rapid progress in cyberinfrastructure in geosciences is providing seismologists an enormous boost for addressing multi-physical phenomena of regional seismic activities.The inherent nature of their multi-scale properties,from temporal to spatial spaces,makes it inevitably to be solved using large-scale computations and distributed parallel data processing schemes.Under such circumstance,using the advanced numerical algorithms and unstructured mesh generation technologies become the obstacles for m...  相似文献   

石漠化信息提取与时空演变分析——以贵州威宁县为例     

李玲  蔡忠亮  陈忠超  李琴  孙俊英 《测绘地理信息》2022,47(2):115-118

以贵州省威宁县为研究区,运用多端元光谱混合分析法(multiple endmember spectral mixture analysis,MES-MA)从2000年、2010年、2015年Landsat影像中提取石漠化信息,分析其时空演变特征.结果表明:该县石漠化主要呈面状连片分布,西北、中部较严重.2000-201...  相似文献   

亚洲地震委员会(ASC)第五次大会在亚美尼亚召开     

吴忠良 《国际地震动态》2004,(12):29-31

亚洲地震委员会(ASC)第五次大会(5^th General Assembly)2004年10月18—21日在亚美尼亚首都埃里温(Yerevan)召开。出席这次大会的代表275人,来自51个国家或地区,其广泛性超过前4届。ASC大会国际学术顾问委员会(International Advisory Committee)主席由．ASC前主席H.Gupta担任,副主席为陈运泰和上田诚也。  相似文献   

有耗媒质中脉冲响应的研究   总被引：1，自引：0，他引：1  

沈飚  于东海 《物探化探计算技术》1996,18(4):304-309

本文详细论述了一维有耗媒质中脉冲响应的正演理论及其模拟技术。深入研究了导电率、介电常数对脉冲响应的影响。以平面脉冲电磁波在一维介质中的传播理论为基础，编制脉冲响应的仿真模拟软件。最后，用实际模型验证了该模拟技术的正确性和可靠性。  相似文献