共查询到20条相似文献，搜索用时 31 毫秒
1.
This paper analyses the global tendency of the sea level rise (SLR) and its long term influence on the sea level upstream drainage cascade based on the example of the level’s variation in the Vistula Lagoon of the Baltic Sea compared to the other lagoons and coastal regions of the southeastern part of the Baltic Sea. A steady positive trend in the water level variations was revealed; its magnitude varies significantly depending on the time period. In general, during the 100–150 year period, the rate of the SLR in the lagoons and coastal areas of the Baltic Sea (1.7–1.8 mm per year) is close to the SLR rate in the World Ocean. In the second half of the 20th century, the increased rate of the SLR in the lagoons and marine areas became stronger (up to 3.6 mm per year in the Vistula Lagoon and in 1959–2006 in the sea and exceeded the rate of global ocean SLR). It dramatically increased at the end of the last century both in the lagoons and in the sea (up to 10.0–15.0 mm per year). This is the response not only to the global climate warming but it is likely that it is also a response to the changes of the climate driving forces that influence the regimes of the local wind and precipitation in the catchment. 相似文献
2.
Two 2×10‐year climate change experiments made with the Rossby Centre regional Atmospheric climate model (RCA) are reported. These two experiments are driven by boundary data from two global climate change simulations, one made with HadCM2 and the other with ECHAM4/OPYC3, in which the global mean warming is virtually the same, 2.6°C. The changes in mean temperature and precipitation show similarities (including broadly the same increase in temperature and in northern Europe a general increase in annual precipitation) as well as differences between the two RCA experiments. These changes are strongly governed by the driving GCM simulations. Even on the RCA grid box scale, the differences in change between RCA and the driving GCM are generally smaller than the differences between the two GCMs. Typically about a half of the local differences between the two RCA simulations are attributed to noise generated by internal variability, which also seems to explain a substantial part of the RCA‐GCM differences particularly for precipitation change. RCA includes interactive model components for the Baltic Sea and inland lakes of northern Europe. The simulated changes in these water bodies are discussed with emphasis on the wintertime ice conditions. Comparison with an earlier RCA experiment indicates that a physically consistent treatment of these water bodies is also of importance for the simulated atmospheric climate change. 相似文献
3.
基于卫星图像重建了近30年来广西南流江河口区一片红树林的扩张过程,结果表明：自1988年至2013年,该红树林向海显著扩张,面积由60公顷增加为134公顷。红树林的自然扩张并非渐进式,而是集中发生于某些特定时期。为了研究控制红树林扩张的动力机制,本文研究了近几十年来红树林潮坪高程演变和区域气候变化过程,同时也分析了水动力状况和营养盐供应的变化情况。研究表明：在滩面高程达到红树林幼苗存活最低高程的前提下,台风强度、频率和冬季低温是控制该红树林扩张的关键因素。红树林湿地的显著扩张只发生在台风强度和频率较低、冬季较为温暖的时期。而在台风频率和强度较高、冬季较为寒冷的时期,由于红树林幼苗难以存活,红树林则难以扩张。在过去几十年间,由于该区域适宜红树林扩张的时期较为罕见,从而导致了红树林扩张过程的不连续性。与气候因素相比,营养供应和水动力状况并不是控制该红树林扩张的关键因素。 相似文献
4.
The sensitivity of the Baltic Sea mean salinity to climatic changes of the freshwater supply is analyzed. The average salinity of the Baltic Sea is about 6‰. The low salinity is an effect of a large net freshwater supply and narrow and shallow connections with the North Sea. As a result of mixing in the entrance area, a large portion of the outflowing Baltic Sea water returns with the inflowing salty water and thus lowers the salinity of the Baltic Sea deep-water considerably. This recycling of the Baltic Sea water is a key process determining the salinity of today's Baltic Sea. The sensitivity of this recycling, and thus of the Baltic Sea salinity, to climatic changes in the freshwater supply is analyzed. A simple model is formulated for the variations of the Baltic Sea freshwater content. Historical data of the freshwater supply and the salinity in the Baltic Sea are used in the model to achieve an empirical expression relating variations of the recycling of Baltic Sea water to the variations of the freshwater supply. The recycling is found to be very sensitive to the freshwater supply. We find that an increase of freshwater supply of 30% is the level above which the Baltic Sea would turn into a lake. Recent climate modeling results suggest that river runoff to the Baltic Sea may increase dramatically in the future and thus possibly put the Baltic Sea into a new state. 相似文献
5.
Resuspension patterns in the Baltic proper 总被引：2，自引：0，他引：2
Waves induce resuspension of surface sediments and contribute to the long-term mobilisation of particulate matter from erosion to accumulation bottoms. This has a major impact on the nutrient cycle in shallow seas by enhancing degradation, microbial production and recycling. The Baltic Sea represents such an area. The aim of this work is to analyse the spatial and temporal resuspension patterns in the Baltic Sea. To estimate the bottom friction velocity, modelled wave data are used in combination with data on grain size. This new data set is compared to a resuspension threshold of friction velocity to estimate the events of resuspension.The variation in bottom friction velocity, resuspension frequency and duration are related to wind climate, fetch, water depth and sediment type. Substantial resuspension can be found down to 40–60 m, with durations from one day to as much as two weeks. The highest winds in the area are highly anisotropic with a dominance of S-SW-W winds and the highest resuspension frequencies are found along the shallow eastern coasts. A seasonal pattern is observed with relatively high friction velocities and high resuspension frequencies during winter. There is also a variation depending on grain size, where sediments with fine and medium sand have a considerably higher percentage of resuspension events than bottoms with other dominant grain sizes. Five sub-areas are identified, characterised by different sediment types, resuspension and wind characteristics. If, in the future, wind speed increases as predicted, resuspension of sediments will also increase with effects on the nutrient cycle. 相似文献
6.
Swagata Bisoi 《Marine Georesources & Geotechnology》2017,35(7):905-920
Global warming is expected to change the wind and wave patterns at a significant level, which may lead to conditions outside current design criteria of monopile supported offshore wind turbine (OWT). This study examines the impact of climate change on the dynamic behavior and future safety of an OWT founded in clay incorporating dynamic soil–structure interaction. A statistical downscaling model is used to generate the time series of future wind speed and wave height at local level. The responses and fatigue life of OWT are estimated for present and future periods and extent of change in design is investigated at offshore location along the west coast of India. Wind speed, wave height, and wave period data are collected from the buoy deployed by Indian National Centre for Ocean Information Services and the future climate for the next 30 years is simulated using the general circulation model corresponding to Special Report on Emission Scenarios A1B scenario. The OWT is modeled as Euler–Bernoulli beam and soil–structure interaction is incorporated using nonlinear p-y springs. This study shows that changes in design of OWT are needed due to increased responses owing to the effect of climate change. Fatigue life is found to be decreased because of climate change. 相似文献
7.
8.
根据野外调查、土层厚度测定、室内粒度分析、CaCO3含量分析和微结构鉴定资料,研究了西安地区约8500aBP来气候变化与风尘堆积的变化。结果表明,西安地区全新世以来的气候与末次间冰期第1阶段气候相比具有频繁变化和变异特点;3100aBP以来风尘堆积与沙尘暴活动比75～10kaBP之间的末次冰期还要强,风尘堆积与沙尘暴活动强的原因主要是气候的变干。全新世黄土发育条件分析表明,黄土高原的黄土可以发育在冰期,也可以发育在与现代气候相近的间冰期,可以发育在冬季风占优势的气候条件下,也可以发育在冬、夏季风活动强度相近的条件下。全新世气候的不稳定性为预测未来长期气候变化带来了不确定性,深入研究全新世气候变异特点对预测未来长期气候变化具有非常重要的意义。 相似文献
9.
西太平洋海区浮游植物的分布受气候变化影响,在不同时空尺度上呈现不同的变化。本研究旨在通过对历史文献及数据资料分析,建立气候变化响应概念模型来探讨Chl-a、海水表面温度(SST)及营养盐如何响应长期气候变化。分析了西太平洋不同区域Chl-a与气候变化相关因子SST及海水营养盐(硝酸盐)的相关性,对模型参数进行选择及验证,来探讨该海区Chl-a是如何响应长期气候变化。结果表明,K2站位Chl-a浓度与SST、硝酸盐浓度呈显著正相关关系,与该海区存在上升流有关;而S1、XT站位均呈现负相关关系,可能与海水水温升高导致层化加剧、营养输入减少有关。本研究为进一步完善和优化西太平洋海区的浮游植物的气候变化响应模型奠定基础。 相似文献
10.
Rapid warming of Large Marine Ecosystems 总被引：4，自引：1，他引：3
The need to understand local effects of global climate change is most urgent in the Large Marine Ecosystems (LMEs) since marine ecosystem-based management requires information on the LME scale. Reported here is a study of sea surface temperature (SST) change in the World Ocean LMEs in 1957–2006 that revealed strong regional variations in the rate of SST change. The rapid warming in 1982–2006 was confined to the Subarctic Gyre, European Seas, and East Asian Seas. These LMEs warmed at rates 2–4 times the global mean rate. The most rapid warming was observed in the land-locked or semi-enclosed European and East Asian Seas (Baltic Sea, North Sea, Black Sea, Japan Sea/East Sea, and East China Sea) and also over the Newfoundland–Labrador Shelf. The Indian Ocean LMEs’ warming was slow, while two major upwelling areas – California and Humboldt Currents – experienced a slight cooling. The Subarctic Gyre warming was likely caused by natural variability related to the North Atlantic Oscillation. The extremely rapid surface warming in the enclosed and semi-enclosed European and East Asian Seas surrounded by major industrial/population agglomerations may have resulted from the observed terrestrial warming directly affecting the adjacent coastal seas. Regions of freshwater influence in the European and East Asian Seas seem to play a special role in modulating and exacerbating global warming effects on the regional scale. 相似文献
11.
《Marine Policy》2013
Benefits humans rely on from the ocean – marine ecosystem services – are increasingly vulnerable under future climate. This paper reviews how three valued services have, and will continue to, shift under climate change: (1) capture fisheries, (2) food from aquaculture, and (3) protection from coastal hazards such as storms and sea-level rise. Climate adaptation planning is just beginning for fisheries, aquaculture production, and risk mitigation for coastal erosion and inundation. A few examples are highlighted, showing the promise of considering multiple ecosystem services in developing approaches to adapt to sea-level rise, ocean acidification, and rising sea temperatures.Ecosystem-based adaptation in fisheries and along coastlines and changes in aquaculture practices can improve resilience of species and habitats to future environmental challenges. Opportunities to use market incentives – such as compensation for services or nutrient trading schemes – are relatively untested in marine systems. Relocation of communities in response to rising sea levels illustrates the urgent need to manage human activities and investments in ecosystems to provide a sustainable flow of benefits in the face of future climate change. 相似文献
12.
我国近海区域对气候变化高度敏感,浮游植物生态的变化关系到我国近海生态安全.采用重构的遥感数据等资料,分析并综述我国近海区域浮游植物叶绿素a浓度、初级生产力和浮游植物群落结构对气候变化背景下海水升温、风场等环境因子的响应.结果表明,东(南)中国海叶绿素a浓度略有上升(下降)的趋势,但浮游植物群落结构和生物量有明显的变化;其中,微微型浮游植物和甲藻占比增加,小型浮游植物物种成为海区优势种,暖水性种分布区北扩,而这与气候变化背景下海洋热动力环境的长期变化及其对营养盐供给的影响关系密切.分析还指出了气候变化对我国近海区域海洋生态影响研究迫切需要开展的若干工作. 相似文献
13.
红树林是以红树植物为主体的常绿灌木或乔木组成的潮滩湿地木本植物群落, 具有“四高”特性(高生产力、高归还率、高分解率和高抗逆性)的典型海洋生态系统; 目前, 全球约有红树林1700万公顷, 主要分布在南北半球25℃等温线内。红树林生态系统的净初级生产力高达2000gC·m-2·a-1, 具有高强度的物质循环、能量流动以及丰富的生物多样性, 对热带、亚热带海洋生态系统的维持与发展起到关键作用, 并在全球变化过程中扮演着十分重要的角色。近30年来, 全球气候变化已引起了国内外学者的极大关注。红树林生态系统位于热带、亚热带海岸潮间带, 是一个脆弱的、敏感的生态系统, 也是首先受全球气候变化影响的典型海洋生态系统之一。作为全球海岸带地区应对全球气候变化最为重要的生态屏障之一, 气候变化将严重影响着全球红树林的生存和分布方式。本文将从全球变暖、海平面上升、大气中CO2浓度的增加和极端天气4个主要方面, 揭示全球气候变化对红树林生态系统的影响与变化特征, 阐述红树林对全球变暖、海平面上升、大气中CO2浓度增加和极端天气响应与适应的生态学机制, 并简要概述了红树林在减缓全球气候变化危害中的重要作用。全球气候变化也将为红树林的研究、保护和发展带来机遇与挑战。 相似文献
14.
CMIP5模式对南海SST的模拟和预估 总被引：4，自引：1，他引：3
分析了32个CMIP5模式对南海历史海表温度(SST)的模拟能力和不同排放情景下未来SST变化的预估。通过检验各气候模式对南海历史SST增温趋势和均方差的模拟,发现大部分模式都能较好地模拟出南海20世纪历史SST的基本特征和变化规律,但也有部分模式的模拟存在较大偏差。尽管这些模拟偏差较大的模式对SST多模式集合平均的影响不大,但会增加未来情景预估的不确定性。剔除15个模式后,分析了南海SST在RCP26、RCP45和RCP85三种排放情景下的变化趋势,发现在未来百年呈明显的增温趋势,多模式集合平均的增温趋势分别为0.42、1.50和3.30℃/(100a)。这些增温趋势在空间上变化不大,但随时间并不是均匀变化的。在前两种排放情景下,21世纪前期的增温趋势明显强于后期,而在RCP85情景下,21世纪后期的增温趋势强于前期。 相似文献
15.
海洋生态系统净生产力 （net ecosystem production，NEP） 表示总初级生产力 （gross primary production，GPP） 和呼吸作用 （respiration，R） 过程之间的差异，它对碳收支平衡、海洋生态系统营养状态乃至气候变化等研究具有十分重要的指示意义。影响海洋 NEP 的因素有细菌、浮游生物、温度、太阳辐射、海冰融化、水团迁移、富营养有机质排放以及海水酸化等。目前计算 NEP 的方法可分为实验培养测定及数据模型计算两种。溶解氧培养法及同位素标记法等是经典的培养测定方法，但存在误差较大且重现性较差等问题。数据模型计算即借助养分质量平衡、响应面模型、O2/Ar 示踪等方法，通过将现场实测数据和生物地球化学模型结合，进行高时间分辨率的连续性观测，这也是目前测算 NEP 的主流应用手段。然而，相较于发达国家，我国在 NEP 的研究设备、技术、测定方法等方面仍存在一定差距。今后的研究重点将是建立 NEP 指标与表征海洋环境、气候变化之间的耦合关系以及 NEP 测定方法的改进，这将有助于深入理解和探索全球变化背景下海洋生态系统响应机制及变化趋势。 相似文献
16.
E. M. Volodin 《Izvestiya Atmospheric and Oceanic Physics》2008,44(3):288-299
The paper considers a relation between equilibrium global warming at doubled carbon dioxide (climate sensitivity) and the distribution of clouds and relative humidity in 18 state-of-the-art climate models. There is a strong correlation among three indices: (1) model climate sensitivity, (2) mean cloud amount change due to global warming, and (3) the difference in cloud amount between the tropics and midlatitudes. In the simulation of the present-day current, models with high sensitivity produce smaller clouds amounts in the tropics and larger cloud amounts over midlatitude oceans than models with low sensitivity. The relative humidity in the tropics is smaller in models with high sensitivity than in models with low sensitivity. There is a similarity between vertical profiles of cloud amount and relative humidity under global warming and vertical profiles of the difference in these quantities averaged over the tropics and midlatitudes. Based on the correlations obtained and observations of cloud amount and relative humidity, an estimate is made of the sensitivity of a real climate system. 相似文献
17.
The Arctic Climate Impact Assessment (ACIA) is a project of the intergovernmental Arctic Council, intended to synthesize knowledge of the effects of climate change on the Arctic. This paper is based on the primary output of the ACIA project, a 1042 page book entitled Arctic Climate Impact Assessment. Our concern is with the effects of Arctic climate change on fisheries. To set the stage, however, we first discuss those chapters that logically precede the fisheries discussion, the chapters concerned with past and present climate change, climate modeling and marine systems. The conclusion notes that moderate climate warming will probably benefit most Arctic fisheries. The conclusion also considers the role of anthropogenic causation in climate change and its policy implications. 相似文献
18.
The Norwegian fishing areas extend over various marine ecosystems that will respond differently to climate change. In the North Sea the productivity of the boreal fish species are likely to decrease under global warming and new warm-water species are expected to become more abundant. In the arctic marine ecosystem of the Barents Sea the fish productivity is expected to increase and their distributions expand northward and eastward under global warming increasing the importance of the Russian as well as the Norwegian sectors of the Barents. In the past, decadal-scale climate variations have been shown to strongly influence productivity and distributions of fish stocks. The importance of such shorter-term variations are expected to continue also under global warming. Under global warming the optimum temperature for fish farming along the Norwegian coast will be displaced northwards from the northern part of West Norway towards the Helgeland coast. 相似文献
19.
近年来国内外学者采用不同的方法评估气候变化对粮食生产的影响,其中机理模型评价方法是运用较多的方法之一。WOFOST（WOrld FOod STudies）模型由于其机理性强、源代码开放、参数调整较为简便等优势,已经在相关研究中得到广泛应用。该模型以不同作物生长发育的机理过程为依据,经过适用性验证后,可用于粮食作物气候生产潜力评估和气象灾害影响评价;结合历史气候资料与未来气候情景数据,可定量评价过去及未来气候变化对粮食生产的影响。通过介绍WOFOST模型的基本原理、运行机制、参数设定与参数本地化等相关方法,系统总结该模型在评估气候变化对粮食生产影响方面的研究进展,并指出现有研究存在的不足,以期为未来开展相关研究工作提供参考。 相似文献
20.
Ronald Neilson建立了一个计算机模型(Neilson模型)以探索植物群落和气候的关系。论文以上海石化监测站气象组2004年气象数据和金山地区的植物群落组成,以及以此数据作成气候图对照世界范围的陆地植物群落地理分布区系气候图来检验尼尔逊模型的正确性。结果显示:走尼尔逊模型路线图的结果与近年来上海自然博物馆专家对大金山岛自然植被的调查结果相吻合,本地区气候图与陆地植物群落类型典型气候图对照结果也与走尼尔逊模型路线图的结果相一致。这证明了尼尔逊模型路线图适合于金山地区自然陆地植物群落类型的。其现实意义在于能根据金山地区气象数据追踪金山地区自然陆地植物群落类型的变化,从而反映全球气候变暖对金山地区自然陆地植物群落的影响。 相似文献