Numerical Study of the Oil Spill Trajectory in Bohai Sea,China     

Zengan Deng  Ting Yu  Suixiang Shi  Jiye Jin  Xiaoyi Jiang  Linchong Kang 《Marine Geodesy》2013,36(4):351-364

Sixteen numerical experiments are conducted using the General NOAA Operational Modeling Environment (GNOME) to numerically study the oil spill trajectory in the Bohai Sea, China, for the purpose of providing information for the oil cleanup and disaster mitigation. High resolution coastline and topography data investigated by China's 908 Program are used to accurately describe the regional geographic feature of the Bohai Sea. Currents and waves required by GNOME are generated by the Hybrid Coordinate Ocean Model and Simulating Wave Nearshore, respectively. Experimental results show that oil spilled in different seasons and at different locations will result in completely different spilling trajectories, traveling distances, and polluting areas. Knowing that information comprehensively is vital to pollution control. Another important goal of this work is to provide users with simulated oil spill trajectory information through China Digital Ocean Prototype System (CDOPS), a grand marine information platform for managing, displaying, and public sharing of the data investigated by the China 908 Program. Users can obtain the trajectory, spreading, and potential impact area of the spilled oil through the oil spill module in CDOPS.  相似文献   

Effects of the external carbon sources on the microbes in the simultaneous biological removal of SO2 and NO x process     

Wenbo Zhou  Ping Zou  Peishi Sun  Xiaoyi Bi  Jie Wang  Jinquan Chen  Haiyu Wang 《Environmental Earth Sciences》2013,70(5):2381-2386

Effects of sodium acetate and glucose on the microbes from the simultaneous flue gas desulfurization and denitrogenation tandem biotrickling process were respectively investigated. For the acidophiles, although the impacts of the carbon sources on the total microbial growth and nitrogen conversion in the medium were slight, the sulfite oxidation rate was obviously improved. The highest sulfite ion oxidation ratio in 48 h was up to 47.2 % as 258.08 mmol L^?1 sodium acetate was added in the medium. For the neutrophiles, the two carbons promoted the total microbial growth, but only sodium acetate could enhance the nitrite consumption significantly. The best nitrite consumption rate in 48 h could reach to 86.7 % with 258.08 mmol L^?1 sodium acetate. It provides valuable information for the development of biological SO₂ and NO _x simultaneous purification process.  相似文献   

北京雾和霾临界气象条件的气候变化特征     

杨若子  房小怡  高云 《气象与环境科学》2017,40(3):14-20

近年来北京市频繁遭受雾和霾天气的影响,表现为天数增多、持续时间增长的特点,这一变化越来越受到专家学者的重视。气象条件是雾和霾污染形成的客观因素。利用北京市观象台多年雾和霾天气(2013-2015年)和气象要素(1961-2015年)观测资料,从气候变化角度出发,研究雾和霾临界气象条件的气候变化特征。研究结果表明:对雾和霾的形成有促进作用的临界气象条件是日平均风速≤1.9 m/s,日相对湿度≥76%,偏南方向的风向;对雾和霾的形成有抑制作用的临界气象条件是日平均风速≥2.6 m/s,日相对湿度≤69%,日降水量≥0.5mm。1961-2015年北京市观象台低风速日数呈增加趋势,且多为西南方向,高风速日数呈减小趋势,污染物清除能力下降,对污染物的累积起关键性作用;相对湿度较高的日数呈减小趋势,相对湿度较低的日数呈增加趋势;日降水量较大的日数呈下降趋势。三种气象条件中相对湿度条件随年代的变化有利于雾和霾的消散,而风速风向和降水量条件随年代的变化不利于雾和霾的扩散和沉降。但有研究表明,在雾和霾污染的形成消散过程中,风速条件起决定性作用,故北京地区较低风速日数的增加是导致大气污染的重要原因。此外,不利的风向条件加重了北京地区污染物的积累聚集。  相似文献   

长江江苏段江面雾的特征和预报着眼点     

田小毅  朱承瑛  张振东  鲍婧 《气象》2018,44(3):408-415

利用2010—2013年长江江苏段沿线布设的36套自动气象站每分钟1次的能见度、相对湿度、温度、风向和风速等实况监测资料,对江面雾的时空分布特征和气象要素进行了统计分析,结果显示:江面雾主要发生于6、11和1月;主要形成于19时至次日07时,其中02—04时最多,结束于06—12时,持续时间以3～9h为主。成雾时相对湿度基本在85%以上;主要的温度区间为春季5～19℃、夏季18～26℃、秋季7～23℃、冬季0～11℃;春、夏、秋三季风速都在5m·s~(-1)以下,冬季风稍大些,甚至在6m·s~(-1)左右的风速下仍然会生成雾,春季以1～2m·s~(-1)的NNE—E为主;夏季以0.3～1m·s~(-1)的NNE—ESE为主;秋季以0.3～2m·s~(-1)的NNE—NE和E—ESE为主;冬季以1～2m·s~(-1)的NNE—NE和WNW为主。此外,对出雾时首站的能见度变化进行分析,发现稳定的江面雾形成之前也会形成明显的"象鼻形"先期振荡特征,这一特征给江面雾的预警预报提供了依据。  相似文献   

北京城镇规划对气象条件影响的定量分析     

王晓云  王昕瑶  李忠良  程宸  曾宪宁  房小怡 《气象科学》2018,38(3):351-360

针对北京地区城镇化快速发展带来的气象环境问题,选取夏季晴天典型个例,采用数值模拟的方法,研究了2004—2020年北京城市总体规划方案中新城建设、绿地增加和水体恢复的环境效应。结果表明:规划对夏季六环内高温、小风、低湿的气象环境有所改善。其中,城镇用地增长地区,气温增幅达1~2℃,夜晚最大;风速和比湿的降幅分别在0.2~1 m·s~(-1)、0.2~1 g·kg~(-1)之间,白天降幅最大;在城镇扩张周边地区,气温的受影响范围最大,白天可达城镇增长面积的3倍,增幅在0.2~1℃;风速和比湿的降幅影响范围都在城镇增长面积的0.3~0.5倍之间,且晚上风速影响范围广,比湿白天影响幅度和范围大。以亦庄为例,基于地理信息系统的精细分析表明,城镇用地增长率与气温增幅、风速降幅和比湿降幅都成线性正相关关系。当城镇用地增长率达到15%~30%时,气象要素的变化幅度会急剧加大。因此,初步建议在城镇规划中将建设用地的增长率控制在20%以内,将用地扩张对局地气象环境造成的不良影响降到最低。  相似文献   

三维地理信息系统（3D—GIS）的发展现状及趋势   总被引：15，自引：0，他引：15  

姜小轶  孙运生 《世界地质》1998,17(4):58-62

地理信息系统技术已经被大量应用于资源管理,环境监测,城市规划,土地管理及交通,水利,林业等领域,但ＧＩＳ技术的发展还远没有止境。人们已经不满足于传统的二维ＧＩＳ软件平台,取而代之的是空间的,立体的三维ＧＩＳ。但由于３Ｄ－ＧＩＳ包括了第三个坐标以及从平面到立体的换算,所以增加了大量的存储量和额外的数据量,因而时至今日,真正的３Ｄ－ＧＩＳ软件还很少。本文一方面介绍了３Ｄ－ＧＩＳ的概念,特点以及发展现状  相似文献   

Evaluation of a micro-scale wind model’s performance over realistic building clusters using wind tunnel experiments   总被引：2，自引：0，他引：2  

Ning Zhang  Yunsong Du  Shiguang Miao  Xiaoyi Fang 《大气科学进展》2016,33(8):969-978

The simulation performance over complex building clusters of a wind simulation model(Wind Information Field Fast Analysis model, WIFFA) in a micro-scale air pollutant dispersion model system(Urban Microscale Air Pollution dispersion Simulation model, UMAPS) is evaluated using various wind tunnel experimental data including the CEDVAL(Compilation of Experimental Data for Validation of Micro-Scale Dispersion Models) wind tunnel experiment data and the NJU-FZ experiment data(Nanjing University-Fang Zhuang neighborhood wind tunnel experiment data). The results show that the wind model can reproduce the vortexes triggered by urban buildings well, and the flow patterns in urban street canyons and building clusters can also be represented. Due to the complex shapes of buildings and their distributions, the simulation deviations/discrepancies from the measurements are usually caused by the simplification of the building shapes and the determination of the key zone sizes. The computational efficiencies of different cases are also discussed in this paper. The model has a high computational efficiency compared to traditional numerical models that solve the Navier–Stokes equations, and can produce very high-resolution(1–5 m) wind fields of a complex neighborhood scale urban building canopy(～ 1 km ×1km) in less than 3 min when run on a personal computer.  相似文献   

土壤添加物对土-水曲线和土体收缩的影响   总被引：3，自引：0，他引：3       下载免费PDF全文

邢旭光  柳烨  马孝义 《水科学进展》2016,27(1):40-48

为探索不同添加物(小麦秸秆、麦壳和植物油渣)对土壤持水性能和土壤收缩特性的影响,定量掺混3种粉末,采用离心机法测定土-水曲线,并对土壤持水能力和土壤收缩特征进行评价。结果发现:各处理土-水曲线形态无差异,van Genuchten模型可用于此条件土-水曲线拟合;3种添加物均可提高土壤容重和土壤含水率并利于保水,且土壤持水能力表现为油渣 >麦秆 >麦壳 >纯土;随着土壤脱水,土体以轴向收缩为主,三直线模型可用于土壤收缩曲线拟合,土体线缩率与吸力和含水率分别满足对数和Logistic函数关系;土体几何收缩量表现为麦壳 <油渣 <麦秆 <纯土,土壤开裂程度表现为油渣 <麦秆 <麦壳 <纯土。  相似文献   

数字海洋应用服务系统构建及关键技术研究          下载免费PDF全文

康林冲  姜晓轶  吕憧憬  宋丽丽  韩璐遥  王漪  蒋冰 《应用海洋学学报》2016,35(4):585-592

我国首次探索了"数字海洋"从科学概念到工程实体的建设实践,经过系统建设和运行过程取得了显著成果,同时存在的问题逐渐显现出来.本研究总结了数字海洋原型系统存在的问题,在此基础上,开展了数字海洋应用服务系统系统架构设计,功能研发以及关键技术研究.通过实践证明,系统在数据共享、信息集成和可视化表达等方面具有良好的应用前景.  相似文献   

黑潮延伸体海表温度锋位置的变化特征   总被引：2，自引：1，他引：1  

王焱鑫  杨小怡  胡建宇 《海洋学报(英文版)》2016,35(7):30-35

High spatial resolution sea surface temperature(SST) data from 1993 to 2013 are used to detect the position of the Kuroshio Extension sea surface temperature front(KEF) from 141°E to 158°E,and the seasonal,monthly and interannual-to-decadal variations of the KEF position are investigated.The latitudinal position of the KEF varies with longitudes:the westernmost part of the KEF from 141°E to 144°E is relatively stable,whereas the easternmost part from 153°E to 158°E exhibits the largest amplitude of its north-south displacement.In the light of the magnitudes of the standard deviations at longitudes,then the KEF is divided into three sections:western part of the KEF(KEFw,141°–144°E),central part of the KEF(KEFc,144°–153°E) and eastern part of the KEF(KEFe,153°–158°E).Further analysis reveals that the KEFw position is dominated by the decadal variability,while the KEFc and KEFe positions change significantly both on interannual and decadal time scales.In addition,the KEFw position is well correlated with the KEF path length.The possible mode leading to the decadal oscillation of the KEFw is further discussed.The KEFw position exhibits significant connections with the Pacific decadal oscillation(PDO) index and the north Pacific gyre oscillation(NPGO) index with a time lag of 40 and 33 months,respectively.  相似文献