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51.
为了保护南极和北极的生态系统和环境,中国自20世纪90年代初开始推行和实施了极地环境监测计划,部署了各学科监测传感器阵列;采集了多学科数据,包括海洋、大气、冰冻圈、生物圈等主题;架构了"R/V雪龙号破冰船—极地考察站—国内基地"之间的快速数据传输网络;建立了海洋环境监测系统、太阳能地面空间监测系统、生态环境监测系统等系列监测系统。为了实现长期监测,达到预测和预警目标,本文针对国内外现状,在现有基础上设计了一套中国极地环境长期监测网(Polar Environment monitoring network of China,CPEMN)。该监测网集成各监测系统并在监测指标设计上覆盖我国极地所有常规监测/观测任务,且根据国际科研动态和长期监测规划拓展了预期监测范围。最后本文利用南极普里兹湾进行的破冰导航应用示范验证了CPEMN具有可执行性。  相似文献   
52.
利用布设在广西区钦州湾的GX11、GX13两套实时在线监测浮标, 研究钦州湾2016年5月发生的红色赤潮藻(Akashiwo sanguinea)赤潮前后实时监测数据的变化情况。结果表明赤潮的暴发与消退受水文气象因素影响, 当寒流过后, 出现风速降低、气温迅速回升, 尤其是气温呈现昼夜温差小的天气状况时, 应重点监控实时在线浮标监测数据的变化。赤潮过程中pH、溶解氧浓度、叶绿素浓度存在明显的昼夜变化规律并高于正常范围, 三种环境要素具有显著的正相关; 当实时在线浮标监测中发现pH、溶解氧浓度、叶绿素浓度呈现较明显联动的强烈波动, 并且数值相对正常范围迅速升高时, 可进行赤潮预警及布置现场调查; pH、溶解氧浓度、叶绿素浓度的实时在线监测可作为预警环境要素, 为赤潮预警提供科学参考。  相似文献   
53.
Quadrature-based approach for the efficient evaluation of surge hazard   总被引:3,自引:0,他引:3  
The Joint Probability Method (JPM) has been used for hurricane surge frequency analysis for over three decades, and remains the method of choice owing to the limitations of more direct historical methods. However, use of the JPM approach in conjunction with the modern generation of complex high-resolution numerical models (used to describe winds, waves, and surge) has become highly inefficient, owing to the large number of costly storm simulations that are typically required. This paper describes a new approach to the selection of the storm simulation set that permits reduction of the JPM computational effort by about an order of magnitude (compared to a more conventional approach) while maintaining good accuracy. The method uses an integration scheme called Bayesian or Gaussian-process quadrature (together with conventional integration methods) to evaluate the multi-dimensional joint probability integral over the space of storm parameters (pressure, radius, speed, heading, and any others found to be important) as a weighted summation over a relatively small set of optimally selected nodes (synthetic storms). Examples of an application of the method are shown, drawn from the recent post-Katrina study of coastal Mississippi.  相似文献   
54.
余永城  王笑  魏夏潞 《气象科技》2022,50(5):653-659
为加快推进福建省气象业务系统的集约化、云化转型,需要依托福建气象大数据云平台(“天擎·福建”)对业务系统进行融入改造。本文介绍了“天擎·福建”的概况、总体架构和功能,重点阐述了福建气象综合业务平台融入“天擎”的技术方案及实现方法,从平台融入“天擎”、数据源切换至“天擎”、算法纳入加工流水线、数据产品存入“天擎”、系统监控进“天镜”、前端页面改造等6个方面实现了应用融入并投入业务运行,融入后综合业务平台的数据汇聚、加工和服务全流程进一步优化和规范,系统运行效率和访问速度显著提高,为其他的业务系统融入天擎提供借鉴。  相似文献   
55.
The analysis of the impact of climate change (CC) on flood peaks has been the subject of several studies. However, a flood is characterized not only by its peak, but also by other characteristics such as its volume and duration. Little effort has been directed towards the study of the impact of CC on these characteristics. The aim of the present study is to evaluate and compare flood characteristics in a CC context, in the watershed of the Baskatong reservoir (Province of Québec, Canada). Comparisons are based on observed flow data and simulated flow series obtained from hydrological models using meteorological data from a regional climate model for a reference period (1971–2000) and a future period (2041–2070). To this end, two hydrological models HSAMI and HYDROTEL are considered. Correlations, stationarity, change‐points, and the multivariate behaviour of flood series were studied. The results show that, at various levels, all flood characteristics could be affected by CC. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
56.
57.
ON SOME KEY SEDIMENTATION PROBLEMS OF THREE GORGES PROJECT (TGP)   总被引:1,自引:0,他引:1  
I. INTRODUCTIONThe Three Gorges Project (TGP) being planned is to be located on the Yangtze River at Sandouplug, 44 km upstream of Yichang (Fig. l). A scheme studied in the feasibility stage has the crest ofthe dam placed at 185 m with a maximums height o…  相似文献   
58.
This paper examines the timing, nature and magnitude of river response in upland, piedmont and lowland reaches of the Tyne basin, northern England, to high-frequency (20–30 year) changes in climate and flood regime since 1700 AD. Over this period fluvial activity has been characterized by alternating phases of river-bed incision and stability coinciding with non-random, decadal-scale fluctuations in flood frequency and hydroclimate that appear to be linked to changes in large-scale upper atmospheric circulation patterns. Episodes of widespread channel bed incision (1760–1799, 1875–1894, 1955–1969) result from a higher frequency of large floods (> 20 year return period) and cool, wet climate under meridional circulation regimes. Phases of more moderate floods (5–20 year return period), corresponding to zonal circulation types (1820–1874, 1920–1954), are characterized by enhanced lateral reworking and sediment transfer in upper reaches of the catchment, and channel narrowing and infilling downstream. Rates of fluvial activity are reduced in intermediate periods (1800–1819, 1895–1919) with no dominant circulation regime associated with lower flood frequency and magnitude. The results of this study provide a valuable guide for forecasting probable drainage basin and channel response to future climate change.  相似文献   
59.
海平面上升对里下河地区洪涝灾害的影响   总被引:1,自引:2,他引:1  
许朋柱 《地理科学》1994,14(4):315-323
  相似文献   
60.
1823 年(清道光三年)我国特大水灾及影响   总被引:4,自引:1,他引:4       下载免费PDF全文
该文对道光三年(1823年)长江下游与华北的严重洪水概况及其对社会经济的影响作了初步探讨,并对这次洪水发生的原因及灾害形成的机制也作了分析,认为了解这次洪水及其产生的影响对于我国减灾战略的制订有重要参考价值。  相似文献   
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