半分析模型在近岸及河口水体透明度反演应用研究

Secchi depth(SD, m) is a direct and intuitive measure of water's transparency, which is also an indicator of water quality. In 2015, a semi-analytical model was developed to derive SD from remote sensing reflectance, thus able to provide maps of water's transparency in satellite images. Here an in-situ dataset(338 stations) is used to evaluate its potential ability to monitor water quality in the coastal and estuarine waters, with measurements covering the Zhujiang(Pearl) River Estuary, the Yellow Sea and the East China Sea where measured SD values span a range of 0.2–21.0 m. As a preliminary validation result, according to the whole dataset, the unbiased percent difference(UPD) between estimated and measured SD is 23.3%(N=338, R~2=0.89), with about 60% of stations in the dataset having relative difference(RD)≤20%, over 80% of stations having RD≤40%. Furthermore, by excluding the field data which with relatively larger uncertainties, the semi-analytical model yielded the UPD of 17.7%(N=132,R~2=0.92) with SD range of 0.2–11.0 m. In addition, the semi-analytical model was applied to Landsat-8 images in the Zhujiang River Estuary, and retrieved high-quality mapping and reliable spatial-temporal patterns of water clarity. Taking into account the uncertainties associated with both field measurements and satellite data processing, and that there were no tuning of the semi-analytical model for these regions, these findings indicate highly robust retrieval of SD from spectral techniques for such turbid coastal and estuarine waters. The results suggest it is now possible to routinely monitor coastal water transparency or visibility at high-spatial resolutions from measurements, like Landsat-8 and Sentinel-2 and newly launched Gaofen-5.     

基于马尔可夫链的旱涝预测应用研究

在阐述马尔可夫思想和预测思想及其原理的基础上,明确了采用此方法的具体步骤和参数值,同时,分析了此方法的优缺点.根据19712000年辽宁省本溪市市区降水量资料,取适当的α值,采用均值-方差法对年降水量进行分级,并应用加权马尔可夫链对该地区的旱涝状态进行了预测,结果表明,预测值与实际值相吻合,说明此方法有一定的实际应用意义.     

History of tectono-magmatic evolution in the Western Kunlun Orogen

Based on the statistical and analytical data on more than 170 isotopic ages published since the 1980s of magmatic rocks, metamorphic rocks, tectonites and ores from the Western Kunlun Orogen, and the characteristics of sedimentation, magmatism, metamorphism and tectonic activities in the region studied in conjunction with geological field investigations and necessary supplementary isotope data, five stages of tectono-magmatic evolution, i.e. Ar³-Pt ₂ ¹ tectono-magmatic active stage (I), pt ₂ ² stable stage (II), Pt ₃ ¹ -p₂ active stage (III), T₁-T₂ stable stage (IV), and T₃-Q active stage (V) can be distinguished in the Western Kunlun Orogen. Moreover, the tectono-magmatic active style and general trend, the characteristics of tectonic settings, etc. of each stage and substage in the region studied are also discussed. Project supported by the State Key Science and Technology Program (No. 305) for the Ninth Five-Year Plan Period of China.     

应用气象要素预测流行性乙型脑炎发病率四十年分析

讨论气象要素与流行性乙型脑炎发病率的关系。40年的数据分析表明,利用当年4月份的平均温度、上一年12月最高温度预测当年的流行性乙型脑炎发病率具有较高的准确性。     

内蒙古东胜地区高岭土矿床的岩石矿物学研究

内蒙古东胜地区高岭土矿床产于鄂尔多斯盆地东北缘上三叠世—中侏罗世煤系地层中 ,该矿包括 T3延长组顶部的 B矿层和 J2 延安组顶部的 A矿层。经薄片鉴定、阴极发光、扫描电镜、电子探针、X光衍射综合分析认为 ,B矿层的原岩为富含钾长石的长石石英砂岩 ,较近源沉积 ,经风化淋滤形成微风化带、不完全风化带、完全风化带及顶部植被带。完全风化带内赋存着化学成分纯、Fe和 Ti含量少的高岭石 ,其矿石结晶度较好 ,以蠕虫状、折扇状高岭石为主 ;A矿层原岩的矿物特征与 B矿层类似 ,但其母岩有 B矿层的物质加入 ,夹有泥岩型高岭土和少量酸性火山物质 ,另外高岭石的结晶度稍次于 B矿层     

IAP／CAS的短期气候距平数值预测研究

本文介绍了中国科学院在气物理研究所（ＩＡＰ／ＣＡＳ）近十年来在短期气候距平数值预测研究方面的一些进展情况,首先介绍了近十年来准业务跨季度汛期降水预测的结果及评分,对预测的物理基础、预测可能性、集合预测方法、订正的必要性与方案进行了初步探讨,提出了我们的看法,发现预测中可能出现多平衡态,可以应用来改进不同区域的预测,并对些方法所作预测的特点、与经验半经验统计的相互配合、不同地区预测效果的差异、如何选     

秦山Ⅲ期核电站工程邻近水域叶绿素a的电布特征

根据 1 995年 1 0月至 1 996年 7月秦山 期核电站邻近水域生态调查资料 ,对叶绿素 a的分布特征进行研究。结果表明 ,该调查水域叶绿素 a含量低 ,表层叶绿素 a平均含量为 0 .2 93mg/m3,底层叶绿素 a平均含量为 0 .2 2 2 mg/m3。叶绿素 a含量的季节变化明显 ,秋季最高 ,其它依次为夏季、春季、冬季。与该水域过去的调查资料进行比较分析 ,发现叶绿素 a的含量有明显下降。     

Three-dimensional high-resolution velocity structure imaging and seismicity study of Yangbi Ms6.4 earthquake

In this study,based on the body wave arrival data of 5506 earthquakes recorded by 32 fixed stations and 94 temporary stations in Yangbi and surrounding areas,th...     

Tide‐modulated hyperpycnal flows off the Huanghe (Yellow River) mouth,China

Few hyperpycnal flows have ever been observed in marine environments although they are believed to play a critical role in sediment dispersal within estuarine and deltaic depositional systems. The paper describes hyperpycnal flows observed in situ off the Huanghe (Yellow River) mouth, their relationship to tidal cycles, and the mechanisms that drive them. Simultaneous observations at six mooring stations during a cruise off the Huanghe mouth in the flood season of 1995 suggest that hyperpycnal flows observed at the river mouth are initiated by high concentrations of sediment input from river and modulated by tides. Hyperpycnal flows started near the end of ebb tides, when near‐bottom suspended sediment concentration (SSC) increased rapidly and salinity decreased drastically (an inverse salt wedge). The median grain size of suspended particles within the hyperpycnal layer increased, causing strong stratification of the suspended sediments in the water column. Towards the end of flood tides, the hyperpycnal flow attenuated due to frictions at the upper and lower boundaries of the flow and tidal mixing, which collapsed the stratification of the water column. Both sediment concentration and median grain size of suspended particles within the bottom layer significantly decreased. The coarser sediment particles were deposited and the hyperpycnal flows stopped. The intra‐tidal behaviors of hyperpycnal flows are closely associated with the variations of SSC, salinity, and stratification of the water column. As nearly 90% of riverine sediment is delivered to the sea during the flood seasons when hyperpycnal flows are active, hyperpycnal flows at the Huanghe mouth and the river's high sediment loads have caused rapid accretion of the Huanghe delta. Copyright © 2010 John Wiley & Sons, Ltd.     

多普勒天气雷达反射率因子产品分析与初步应用

通过对2004年影响桂林的多普勒天气雷达反射率因子的分析，得到了一些强降水及强对流天气反射率因子特征，与径向速度、回波顶高等产品结合使用，归纳出一些短时及临近预报判别指标。