Atmospheric Correction Methods for GF-1 WFV1 Data in Hazy Weather

Increasing hazy weather in the eastern area of China limits the potential application of high-resolution satellite data and poses a huge challenge for the atmospheric correction of remote sensing images. Consequently, it is necessary to find the most suitable atmospheric correction method under hazy condition. In this study, five kinds of atmospheric correction models, including 6S, COST, FLAASH, QUAC, and ATCOR2, are applied to the GaoFen-1 Wild Field Camera (GF-1 WFV1) data in the eastern area of China, and examined by both quantitative and qualitative analyses using the measured spectrum data. Experimental results indicated that ATCOR2 achieves the best performance among the atmospheric correction methods qualitatively and quantitatively. Hence, specifically for the study area and GF-1 WFV1 dataset, ATCOR2 is the most suitable atmospheric correction approach under hazy in the eastern area of China.     

气象科技成果业务应用的痛点和机制改革探索

以需求为牵引,问题为导向,分析气象科技成果应用的新需求,找出了传统气象科技成果应用的痛点和机制管理的弊端,并以天气预报科技成果业务转化为例,提出了科技成果应用新型管理体系的设想。新型管理体系的构建原则及体系框架,对新管理体系的实施关键环节进行了分析。新型管理模式可望有效改进传统管理体系存在的问题,明显提高科技成果转化的效益,使科技成果真正为气象业务现代化建设提供有力的科技支撑。     

微服务在气象数据服务中的应用研究

在气象数据服务逐渐接口化背景下,MUSIC作为CIMISS气象数据接口服务的主要系统,得到了各级业务部门的广泛应用,但也存在不完善和使用难等问题。基于MUSIC以微服务架构设计与开发气象数据服务系统,扩充了MUSIC接口,实现了接口编制、编排和图形化使用,提升了接口使用人性化水平,增强了MUSIC业务支撑能力和业务适应性。     

基于植被和潮动力作用的潮滩剖面演变数值模拟

为研究多因子共同作用下的潮滩演变机制,开发了基于植被生长和潮动力作用的潮滩剖面演变数学模型。在不考虑植被作用下,模拟得到了潮滩中长期演变后的上凸形剖面特征;泥沙供给是决定潮滩宽度的因素,供给越充分,潮滩宽度越大。模型考虑植被过程时,结果表明不同的植被生物量分布形式对潮滩水动力的影响程度不同,在潮间带上部,生物量抛物线分布时的减流效果强于生物量线性分布形式;而在潮间带下部则相反。模拟结果显示盐沼和光滩之间出现陡坎,且随着滩面的逐步淤高,陡坎逐步向海移动。     

A Profile of International Climate Change Science in the Past One Hundred Years*

Climate change is one of the most active research fields currently, which has attracted extensive attention from the international community. In order to better understand the development situation and research status of international climate change science, in this paper we took the SSCI and SCI databases as data sources, collected the relevant literatures since 1900 based on the key words related to climate change, and made some statistics and analysis of the literatures of the past one hundred years to reveal the development process of climate change research as well as the development and evolution of its research topics and hot spots. The results showed that the climate change research began in the late 18 th century and early 19 th century, and the academic debate about global warming and global cooling started in the early 1970s. The international programs and projects led by a range of international organizations and intergovernmental bodies have contributed significantly to the rapid development of climate change research. The United States and the United Kingdom have long been the core countries of climate change research. The proportion of Chinese papers has risen rapidly in the last decade. The intensity and scope of scientific research cooperation are constantly expanding. Current research focuses on climate model/modeling, climate simulation, climate policy, climate sensitivity, climate change impacts, climate change adaptation, climate change mitigation, and rate of climate change.     

云南峨山地区东川群黑山组流纹质碎斑熔岩锆石U－Pb年龄及其地质意义

滇中地区中元古界"昆阳群"、"东川群"的地层层序是长期争议的重大基础地质问题。本次在峨山地区东川群黑山组中发育的厚近5m厚的流纹质碎斑熔岩采集样品D0023一件,选出120余粒锆石,获得的锆石LA-ICP-MS U-Pb加权平均年龄为(1569. 2±4. 5) Ma。样品锆石的Th/U值均大于0. 5,具有清晰的振荡环带结构,均为岩浆成因的锆石,表明东川群黑山组形成于中元古代早期,属非造山相关的火山岩系,可能是哥伦比亚超大陆裂解作用在扬子陆块的响应,为东川群的地层时代和层序研究增添了新资料。     

Garnet amphibolites from the Ganzi–Litang fault zone,eastern Tibetan Plateau: mineralogy,geochemistry, and implications for evolution of the eastern Palaeo-Tethys Realm

The Ganzi–Litang fault zone, an outstanding tectonic element in the eastern Tibetan Plateau has been intensively debated as an in-situ suture zone marking relict of a subducted Palaeo-Tethyan oceanic crust or a failed intracontinental rift. This paper reports the garnet amphibolites discovered along the Ganzi–Litang fault zone, eastern Tibetan Plateau. These garnet amphibolites are characterized by the garnet–hornblende–rutile–sphene–plagioclase–quartz assemblage. Conventional geothermobarometry figures out the metamorphic temperature and pressure conditions at 582–626°C and 1.61–1.82 GPa, respectively. Geochemical analysis (no Nb–Ta deletions and left-inclined to flat patterns of rare-earth elements) indicates that the garnet amphibolites could represent metamorphic product of the mid-ocean-ridge (MORB)-type mafic rocks that were contaminated by a mantle plume. The protolith of the garnet amphibolites was dated at 236 Ma using in-situ U–Pb zircon method, and the retrograde metamorphism was dated at 218 Ma using in-situ U–Pb sphene method. A comprehensive analysis combined with the development of the Palaeo-Tethys Ocean and the Yidun arc through geologic time indicates a Triassic to Early Jurassic age (236–195 Ma) for the metamorphism of the garnet amphibolites. The low geothermal gradient of 9.8ºC/km and the N-MORB nature of the garnet amphibolites suggest a subduction-zone environment for the high-pressure metamorphism. Therefore, the Ganzi–Litang fault zone is a Palaeo-Tethyan suture separating the Yidun arc and the Songpan–Ganzi terrane, representing the relics of a branch of the Palaeo-Tethys Ocean that was contaminated by a mantle plume.     

蚀变洋壳玄武岩俯冲过程中含碳矿物相变质演化及脱碳作用的研究

俯冲作用是连接地表系统和地球深部系统的最为关键的地质过程,其对研究地球深部碳循环具有重要的意义。俯冲洋壳岩石圈中的碳主要存储在沉积物、蚀变洋壳玄武岩以及蛇纹岩中。俯冲变质作用过程含碳岩石的变质演化控制着其中含碳矿物相的转变及碳迁移过程。本文选取了蚀变洋壳玄武岩进行相平衡模拟,来研究其含碳矿物相的变质演化过程。计算结果表明,变质玄武岩体系中的碳酸盐矿物之间的转变反应除了受压力控制之外,还受到温度和体系中铁含量的影响。随着压力的升高蚀变玄武岩中碳酸盐矿物会发生方解石/文石-白云石-菱镁矿的转变,但在高压/超高压条件下,温度的升高可以使菱镁矿转变成白云石。碳酸盐矿物中的铁含量受到体系中铁含量的影响,白云石和菱镁矿中的铁含量随着体系中铁含量的增加而增加。在水不饱和条件下,洋壳不管是沿着低温还是高温地热梯度线俯冲到岛弧深度,蚀变玄武岩体系几乎都不发生脱碳作用。然而在水饱和条件下,当洋壳沿着高温以及哥斯达黎加地热梯度线俯冲到岛弧深度时,蚀变玄武岩体系中的碳几乎可以全部脱出去。蚀变玄武岩体系中水含量的增加可以促进体系的脱碳作用。     

Bioacoustic application on fisheries management in an artificial reefs’ ecological reserve of Bohai Gulf China

Various techniques have been used in marine fishery resources assessment. Among those, acoustic techniques have high efficiency and wide adaptability, and are environment friendly. Therefore, acoustic techniques played a key/indispensable role in the field of ecosystem-based fishery management. Acoustic surveys were conducted during the wet (May) and dry (November) seasons in 2016 in the artificial reefs ecological reserve of Bohai Gulf and a nearby control region to understand the current situation of fishery resources and explore the effectiveness of underwater artificial constructions by a dual-frequency identification sonar (DIDSON) and a scientific split-beam echosounder (120 KHz, Simrad EY60). Fish densities in various seasons and regions showed significant differences and interaction, with a maximum value of 358020.34 ind/n.mile² in the artificial reefs’ region and a minimum value of 71898.35 ind/n.mile² in the control region during the wet season. Fish densities in defined parallel transects revealed a roughly southward migration trend of small-size individuals from wet season to dry season. Single echo detections in the artificial reefs region demonstrated a wider target strength (TS) range (? 60 ~ ? 30 dB vs ? 60 ~ ? 51 dB) and higher mean TS values (? 55.87 dB vs ? 58.31 dB) than the control region both in the wet and dry seasons, which indicated a more complicated and stable fish community structure in the artificial reefs area. The vertical distribution of single echo detections tracked by the echoview post-processing system showed an apparent downward gathering effect. A positive correlation between TS and water depth was discovered from Pearson correlation analysis in the artificial reefs region during the dry season.