西北太平洋黑潮延伸体观测回顾和展望     

陈朝晖  林霄沛  马昕  管延锋  周春  张岳奇  马克 《地学前缘》2022,29(5):13-22

西北太平洋黑潮延伸体是全球海洋动力过程最复杂、对全球气候变化最敏感和全球海洋渔业产量最大的区域之一,然而,目前对该海区物理、生态及生地化循环等过程的认识仍受限于长期连续海洋观测资料的缺乏。本文回顾了国际上针对黑潮延伸体海区的相关观测情况和取得的主要进展,介绍了近年来我国在该区域观测系统的构建工作及取得的初步成果,包括构建了全球首个西北太平洋黑潮延伸体定点观测系统;发现黑潮延伸体海区海洋涡旋的平流效应对该海区模态水的总潜沉率贡献超过一半,所携带当地的模态水只需要一年半的时间就可到达海盆的西边界;基于潜标首次展示了黑潮延伸体区域3种不同类型次温跃层涡旋流速的直接观测结果,为开展其生成消亡机制及其全球次表层物质能量输运提供了重要的现场观测基础。最后,本文展望了今后观测系统的发展方向,即在跨圈层和多学科交叉方面发展成为我国在西北太平洋重要的深远海综合观测网络。这将为揭示多尺度物理-生物过程耦合、深海能量串级及其气候效应与深海碳循环等领域实现突破提供重要的观测支撑。  相似文献   

The investigation of internal solitary waves over a continental shelf-slope   总被引：1，自引：0，他引：1  

Qian Ma  Chunxin Yuan  Xiaopei Lin  Xue&#;en Chen 《中国海洋湖沼学报》2020,38(3):695-706

Internal solitary waves (ISWs) always happen in marginal seas, where stable stratification exists. ISWs may carry large energy when they propagate and affect marine engineering constructions such as marine drilling platforms. Previous studies, including a large number of mooring observations and laboratory experiments, show the speed of ISWs will change when they pass by shelf slopes. Korteweg-de Vries (KdV) theory explain this phenomenon. In the paper, we use a laboratory experiment and a numerical model experiment to verify this theory. In the laboratory experiment, we injected two layers of water of different densities in a tank to simulate marine stratification and make ISWs. We use a CCD camera to record the whole process. The camera can take 16 photos per second. In the numerical experiment, we input the same original conditions as the laboratory one. The results of 18 different original conditions show the dimensionless factor d plays a key role in deciding the amplitudes and shapes of ISWs. The main conclusion also contains that small-amplitude waves match well with KdV theory while mKdV is better for largeamplitude waves. Whether the laboratory experiment or numerical experiment shows results with a high agreement. In future studies, we may use a numerical model with higher resolution to get analysis about phase speed and energy of ISWs.  相似文献   

小清河分洪区洪水演进的数值模拟   总被引：19，自引：0，他引：19       下载免费PDF全文

刘树坤  李士功 《水科学进展》1991,2(3):188-193

本文应用数值模拟方法,对永定河中游的小清河分洪区内分洪时的洪水演进过程进行了模拟计算,在此基础上编制了该分洪区的洪水风险图,并研究了减少分洪区内生命财产损失的若干对策。实践证明,这种成果可作为防洪决策的基础,目前已被某些地区采用。  相似文献   

中心城市信息来源、加工和扩散研究──以《广州日报》为例     

阎小培  姚一民 《热带地理》1996,(4)

本支以信息服务业中的报纸业为研究对象，描述《广州日报》信息来源、加工和扩散的过程，分析其时空变化特征．《广州日报》信息来源的渠道，各渠道的相对重要性，信息的收集和加工的技术效率，信息产品的质量，信息扩散的规模、方式和过程都发生了很大变化，呈现出整体提高的趋势．文章还分析了《广州日报》信息扩散的空间变化特征，并对这些特征的形成因素进行了确定。文章最后还对本案例研究的理论意义进行了讨论，指出；在多个微观案例研究的基础上进行宏观概括将更接近事情的真相。  相似文献   

Review of the Research Progress in Global Warming Hiatus     

Yidan Xu  Jianping Li  Qiuyun Wang  Xiaopei Lin 《地球科学进展》2019,34(2):175-190

From 1998 to 2012, the warming rate of global mean surface air temperature showed significantly slower than before, which is referred to as the global warming hiatus. The causes and underlying mechanisms of this phenomenon are currently a hot topic of climatic change research. The research significance of global warming hiatus was discussed and relevant research progress was reviewed from two perspectives of external forcings and internal variabilities. In term of external forcings, global warming hiatus is mainly affected by solar activities, volcanic eruptions, aerosols and stratospheric water vapor. With respect to internal variabilities, the warming rate of global mean surface air temperature slowdown is mainly related to the natural variabilities of the Pacific Ocean, the Atlantic Ocean, the Indian Ocean and the Southern Ocean and influenced by the related heat redistribution processes. During the global warming hiatus period, some energy is transferred and restored in the deep ocean so as to modulate the global warming rate, rather than there is a reduction of global total energy in the climate system. In addition, the partially coupled forcing pacemaker model experiment was also reviewed. The pacemaker experiment is a powerful tool for studying the characteristics, causes and underlying mechanisms of the global warming hiatus. Besides, some challenges resulted from the global warming hiatus, including the global energy imbalance, data, simulation and related policy-making were summarized, and future research directions were also discussed.  相似文献   

20 世纪90 年代广州市从业人员的社会空间分异   总被引：14，自引：4，他引：10  

魏立华  丛艳国  李志刚  闫小培 《地理学报》2007,62(4):407-417

1990 年以来中国城市的内城区传统工业向郊区外溢,郊区大量劳动密集型国际资本进驻等因素带来城市不同职业从业者的居住空间格局的重构。以1990 年、2000 年广州市“街道层面”的两次人口普查数据为主要数据源,借用经济学中的区位商指标,分析1990~2000 年广州市不同职业从业者的居住空间分异特征,发现工业、低端服务业、高端服务业及政府 机关职员等从业者呈现出差异化的空间分异特征。工业从业者的居住空间从内城区向近郊区、远郊区等转移,低端服务业从业者的居住地一直高度集中于内城区,高端服务业从业者聚居于政府机关附近和高校、科研机构密集区,政府机关职员居住区完全与政府机关相重合。就业地与居住地的临近性是20 世纪90 年代广州城市从业者居住空间最为显著的特征。旧城区产业结构调整、城市空间扩展、郊区国际生产资本进驻、政府为迎合全球化而进行的政策及空间的调整、土地开发与住房商品化以及原有国家事业机关“单位制”居住模式的惯性等成为1990~2000 年广州市不同职业从业者社会空间分异的主要原因。基于区位商的方法来分析不同职业从业者的居住空间分异,为深入解析城市社会空间分异提供了新的研究思路与方法。  相似文献   

Application of multi-channel two-dimensional transient Rayleigh wave exploration in goaf detection     

DU Lizhi  ZHANG Xiaopei  WANG Yong 《世界地质(英文版)》2010,13(1):56-60

The transient Rayleigh wave exploration has high detection accuracy in shallow exploration. The effect of detection array is comprehensive reflection of the velocity of rock and soilmass. Therefore, the rolling multi-channel transient acquisition system has been adopted in this study, which turns one dimensional transient Rayleigh wave exploration into two dimensions, consequently, the two-dimensional velocity distribution of rock and soil mass under the survey line has been achieved. Through comparing with the shallow seismic reflected wave exploration, the result indicates that the rolling multi-channel transient acquisition system has accurate resolution. Thus, in the process of the shallow reflected wave exploration, if the surface wave has developed, the coalition between the reflected wave exploration and the two-dimensional transient Rayleigh wave exploration should actualize the accuracy of exp loration.  相似文献   

近年来中国城市化与全球环境变化研究述评   总被引：3，自引：0，他引：3  

解利剑  周素红  闫小培 《地理科学进展》2010,29(8)

城市化与全球环境变化研究已引起全球范围学者的广泛重视.改革开放以来,我国城市化水平不断上升,城市化质量不断提高,同时城市化也产生资源过度消耗、环境污染、生境退化等诸多问题,尤其是近年来气候异常、自然灾害频发等使学术界更加重视城市化与全球环境变化的研究,开始思考人类应该以怎样的方式处理人地关系的问题.文章在分析国内学者关于城市化与全球环境变化研究的界入视角与关注重点的基础上,对国内研究从研究内容、方法与尺度3方面进行评价,并指出从人文地理学角度出发的3个研究议题,包括城市生计与全球环境变化、城市系统脆弱性与全球环境变化以及城市管治与全球环境变化.  相似文献   

Application of multi-channel two-dimensional transient Rayleigh wave exploration in goaf detection     

DU Lizhi  ZHANG Xiaopei  WANG Yong College of Construction Engineering  Jilin University  Changchun  China 《东北亚地学研究》2010,(1)

The transient Rayleigh wave exploration has high detection accuracy in shallow exploration.The effect of detection array is comprehensive reflection of the velocity of rock and soil mass.Therefore,the rolling multi-channel transient acquisition system has been adopted in this study,which turns one dimensional transient Rayleigh wave exploration into two dimensions,consequently,the two-dimensional velocity distribution of rock and soil mass under the survey line has been achieved.Through comparing with the s...  相似文献   

Contribution of SST change to multidecadal global and continental surface air temperature trends between 1910 and 2013     

Xu  Yidan  Li  Jianping  Sun  Cheng  Lin  Xiaopei  Liu  Hailong  Wang  Lanning  Liang  Yishuang  Wang  Qiuyun  Zhang  Yazhou  Hou  Zhaolu  Wang  Fuchang 《Climate Dynamics》2020,54(3):1295-1313

Climate Dynamics - The global mean surface air temperature (GMST) shows multidecadal variability over the period of 1910–2013, with an increasing trend. This study quantifies the contribution...  相似文献