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1.
“Belt and Road” regions include Asia, Europe and eastern and northern Africa, with a wide spatial distribution. The cryosphere is undergoing rapid changes in the Belt and Road regions with global warming, and has an important impact on water resources, ecosystems and Arctic waterways in these regions. This article reviewed recent cryospheric changes and associated impacts on water resources in the Belt and Road regions during the last decades. The main cognitions are as follows: Most glaciers are shrinking and glacier mass balances are most negative, but there are regional differences in the changes of glaciers. Global temperature rise has resulted in permafrost degradation, including a rise in permafrost temperature and decreasing permafrost thickness as well as an increase in active layer thickness. There is a significant decrease in snow cover extent and an increase in snow depth. Snow cover duration has shortened, the onset of snow cover has delayed, and the end of snow cover has advanced. However, there are still obvious regional differences in the changes of snow cover. Arctic sea ice has declined precipitously in both extent and thickness in summer, and multi-year sea ice has decreased,indicating the precipitous retreat of sea ice. The freeze-up date of some lakes has been delayed, the break-up date has advanced, and the ice cover duration of river/lake ice has significantly shortened. Glacial runoff has increased significantly in China. Snowmelt and permafrost degradation have also increased the basin runoff, which indicates the important impact of cryospheric changes on runoff. This study will provide a baseline and important scientific support for addressing climate change and regional sustainable development.  相似文献   

2.
《Comptes Rendus Geoscience》2018,350(4):141-153
This study deals with the evolution of the hydrological cycle over France during the 21st century. A large multi-member, multi-scenario, and multi-model ensemble of climate projections is downscaled with a new statistical method to drive a physically-based hydrological model with recent improvements. For a business-as-usual scenario, annual precipitation changes generally remain small, except over southern France, where decreases close to 20% are projected. Annual streamflows roughly decrease by 10% (±20%) on the Seine, by 20% (±20%) on the Loire, by 20% (±15%) on the Rhone and by 40% (±15%) on the Garonne. Attenuation measures, as implied by the other scenarios analyzed, lead to less severe changes. However, even with a scenario generally compatible with a limitation of global warming to two degrees, some notable impacts may still occur, with for example a decrease in summer river flows close to 25% for the Garonne.  相似文献   

3.
Climate change has profoundly impacted the development of human civilization. It is one of the basic forces that have led to the rise and fall of regional civilization. The manifestations and ultimate consequences of the impacts of climate change on social development are the products of the interaction between climate change and human society, which are both related to the characteristics of climate change and to the adaptation of human society. Based on the published papers on climate change and civilization during the past 20 years, five patterns of the impacts of climate change on civilization were summarized. They are periodic changes, pulse, adaptive transition, collapse, migration and replacement. Periodic changes and pulse occurred when climate change impacts were within the resilience of human social systems. Thus, there was no need for major structural changes in the human society. Adaptive transition was a fruit of successful response of the human system when the extent of abrupt climatic change or the trend of climate change exceeded the available range of human social systems In contrast, collapse was a result of failed response of the human system. Migration and replacement, in which people moved from their original living place to other regions and sometimes even replaced the aboriginal civilizations with the colonized civilization, could occur no matter the impacts of climate change had exceeded the resilience of human system. The summarization is expected to be useful for the understanding of the mechanism on the relationship between climate change and civilization, and for coping with the challenges of future global climate change.  相似文献   

4.
Since tropical rainfall is important in the global energy and hydrologic cycle, the tropical rainfall changes under global warming have attracted extensive attention around the world in recent decades. The advances in the observational studies and model projection for the tropical rainfall changes under global warming were reviewed here. The frontiers in the mechanism of regional tropical rainfall changes and the approaches of rainfall change research are summarized. The large intermodel spread in the multi-model projections, the sources of uncertainty and the methods to reduce the uncertainty were also introduced. Finally, the challenges about the tropical rainfall changes were discussed.  相似文献   

5.
CMIP研究计划的进展及其在中国地区的检验和应用前景   总被引:7,自引:0,他引:7  
由世界气候研究计划(WCRP)推动制定的CMIP计划,是一整套耦合大气环流气候模式的比较计划.该计划旨在通过比较模式的模拟能力来评价模式的好坏,促进气候模式的发展;同时也为生态、水文、社会经济诸学科在全球变化背景下预估未来环境变化提供可靠的科学依据.CMIP计划从AMIP开始,经历了CMIP1、CMIP2、CMIP3几个阶段的发展,并已为模式研究提供了迄今为止时间最长、内容最为广泛的模式资料库.尽管模式的模拟结果仍不可避免的存在一些不足,但世界各国纷纷利用该资料库进行模式发展以及与气候变化相关的多学科研究,为预估未来的环境变化提供了不可替代的科学依据.对其作了简要回顾,并对其在中国地区存在的问题和潜在应用前景作了简要论述.  相似文献   

6.
为了推动我国关于气候变化对地下水影响的深入研究,列举了关于气候变化对地下水影响的研究方法,包括包气带和含水层环境示踪技术,研究地下水及其沉积物的物理化学指标,地表水-地下水耦合数值模拟技术等;综述了我国华北地区(北京市、滹沱河流域、海河流域、滦河下游地区、黄淮海平原、临汾盆地、鄂尔多斯盆地、黄河下游地区、大同盆地、北方岩溶泉域)、西北地区(塔里木下游地区、三工河流域、阿克苏河绿洲、黑河流域、石羊河流域、河西走廊、巴丹吉林沙漠)和东北地区(吉林中部平原地区、三江平原)等典型区域气候变化(气温、降水、蒸发)对地下水水位、补给量与排泄量(泉流量、开采量)、水化学成分、水温、同位素组成的影响;提出了气候变化条件下合理利用和管理地下水资源的若干对策,包括减缓温室效应引起的全球气候变暖对未来地下水资源产生不利影响,定量化研究气候变化和地下水之间的相互关系,应用高新技术开展地下水资源脆弱性的研究,充分利用灌区地下含水层的调蓄作用,通过地表水与地下水的联合利用控制水盐平衡、涵养地下水源,节约农业、工业和生活用水等。  相似文献   

7.
The research progress of climate suitability at home and abroad was briefly reviewed in this paper, which was divided into three stages: The initial stage of research, the initial development and application stage, and the application research warming stage. The main achievements and progress of climate suitability in China were also introduced from three aspects as follows: Improvement of climate suitability model, extension of climate suitability applications and development of climate suitability model. Based on the impact of climate change on agriculture and the weak links in climate suitability research, the focus and hotspot of future climate suitability research were proposed, which will be five important directions:The climate suitability model proceed from crop growth model, the climate suitability research proceed from characteristic agriculture, the climate suitability research proceed from climate change, the climate suitability model based on different theories and the climate suitability evaluation index research.  相似文献   

8.
介绍了2009年项目"全球变暖背景下东亚能量和水分循环变异及其对我国极端气候的影响"的主要研究目标和内容,着重叙述了项目实施以来的主要科研进展,包括西北敦煌和临泽区陆气交换加强观测试验、我国极端气候的变化分析和模拟研究以及气候预测新方法和新系统的研制等方面.最后概要介绍了项目未来几年的主要研究工作计划.  相似文献   

9.
In the recent decades, a large amount of anthropogenic heat has been absorbed and stored in the Southern Ocean. Results from observations and climate models' simulations both show that the Southern Ocean displays large warming in the upper and subsurface ocean that maximizes at 45°~40°S. However, the underlying mechanisms and evolution processes of the Southern Ocean temperature changes remain unclear, leaving the Southern Ocean to be a hotspot of climate change studies in the recent years. The present study summarized the current progress in the observations and numerical modeling of long-term temperature changes in the Southern Ocean. The effects of changes in wind, surface heat flux, sea-ice and other factors on the ocean temperature changes were presented, along with the introduction to the role of oceanic mean circulation and eddies. The present study further proposed that a deepening of the understanding in the Southern Ocean temperature change may be achieved by investigating the fast and slow responses of the Southern Ocean to external radiative forcing, which are respectively associated with the fast adjustments of the ocean mixed-layer and the slow evolution of the deep ocean. Specifically, the striking and fast mixed-layer ocean warming north of 50°S is tightly related to the surface heat absorption over upwelling regions and wind-driven meridional heat transport, resulting in enhanced warming around 45°S. While in the slow response of the Southern Ocean temperature, the enhanced ocean warming shifts southward and downward, mainly associating with the heat transfer from oceanic eddies. The Southern Ocean temperature has pronounced climatic effects on many aspects, such as global energy balance, sea-level rise, ocean stratification changes, regional surface warming and atmospheric circulation changes. However, large model biases/deficiencies in simulating the present-day climatology and essential ocean dynamic processes last in generations of climate models, which are the main challenge in advancing our understanding in the mechanisms for the Southern Ocean climate changes. Therefore, to achieve reliable future projections of the Southern Ocean climate, substantial efforts will be needed to improve the model performances and physical understanding in the relative role of various processes in ocean temperature changes at different time scales.  相似文献   

10.
正The large-scale summer monsoon circulations of south Asia makes a strong impact on precipitation in the area of southwestern China including Qinghai-Tibetan Plateau and Yun-Gui Plateau.however,the monsoon is both spatially and temporally complex and smaller-scale circulations are forced by a variety of local or regional orographic effects,local or regional land-atmosphere or  相似文献   

11.
The transition area of three natural zones (Eastern Monsoon Region, Arid Region of Northwest China, Qinghai Tibet Plateau Region) is influenced by the Asian monsoon and middle latitude westerly circulation because of its special geographical position. And it is more sensitive to global climate change. The Koppen climate classification, which is widely used in the world, and the accumulated temperature-dryness classification, which is usually used in China, were used to study the climate zones and changes in the region of longitude 97.5°~108°E, latitude 33°~41.5°N, from 1961 to 2010. The changing areas of each climate zone were compared to the East Asian Summer Monsoon index, the South Asian Summer Monsoon index, the Summer Westerly index, the East Asian Winter Monsoon index, the Plateau Summer Monsoon index, the North Atlantic Oscillation index, the Southern Oscillation index, NINO3.4 index, to explore the response of the transition area of three natural zones to each climate system. According to the results, this region will become wetter when the Summer Westerly or the East Asian Winter Monsoon is relatively strong. When the East Asian Summer Monsoon or the South Asian Summer Monsoon becomes strong, the climate in low altitude region of the study area will easily become drier, and the climate in high altitude region of the study area is easily to become wetter. When the Plateau Summer Monsoon is relatively strong, the climate in the study area will easily become drier. When the North Atlantic Oscillation is relatively strong, the study area will easily become wetter. And when the El Niño is relatively strong, or the Southern Oscillation is relatively weak, the study area will easily become drier. In general, the moisture status of this region is mainly controlled by the middle latitude westerly circulation. The enhancement of the Asian summer monsoon could increase the precipitation in the southeast part of this regional, but, according to the degrees of dryness and the types of climate change in this paper, warming effects could offset precipitation increasing and make the area drier. The transition area of three natural zones is influenced by multiple interactions of climate systems from East Asia. A single climatic index, such as air temperature or precipitation, can not completely represent the regional features of climate change. As a result, areas of climate zones can be used as an important index in the regional climate change assessment.  相似文献   

12.
青藏高原地区特殊的大气圈、水圈、冰冻圈、生物圈等多圈层相互作用过程及其变化,不仅对青藏高原及其周边地区的气候格局和变化有重要影响,而且对东亚、北半球乃至全球的环流形势和异常产生深远影响。为此,全球变化研究重大科学研究计划于2010年9月启动了"青藏高原气候系统变化及其对东亚区域的影响与机制研究"项目,旨在开展青藏高原环境、地表过程、生态系统对全球变化的响应及其对周边地区人类生存环境影响的综合交叉研究,以揭示青藏高原气候系统变化及其对东亚区域的影响机制,提出前瞻性的应对气候变化与异常的策略,减少其导致的区域自然灾害的损失。项目实施近3年来,开展了青藏高原首次"星—机—地"综合立体协同观测试验和大规模地气相互作用综合观测试验。在遥感结合地面观测估算青藏高原地表特征参数和能量通量方法,高原地区上对流层和下平流层结构,高原季风与东亚季风和南亚季风之间的内在联系,中国及青藏高原地区太阳辐射和风速的年代际变化趋势,青藏高原春季感热源减弱及其对亚洲夏季风和中国东部降水的影响,以及极高海拔地区土地覆被格局等方面取得了一些突出进展。  相似文献   

13.
Previous genetic studies showing evidence of past demographic changes in African drosophilids suggested that these populations had strongly responded to Quaternary climate changes. We surveyed nine species of Zaprionus, a drosophilid genus mostly present in Africa, in forests located between southern Senegal and Gabon. The mitochondrial COI gene showed contrasted levels of sequence variation across species. Populations of the only cosmopolitan species of the genus, Z. indianus, and of its closely related sibling species, Z. africanus, are highly polymorphic and appear to have undergone a continuous population expansion beginning about 130,000 years ago. Five less variable species probably underwent a population expansion beginning only about 20,000–30,000 years ago. One of them, Z. taronus, was significantly structured between forest blocks. The last two species were nearly monomorphic, probably due to infection by Wolbachia. These results are similar to those obtained in three species from the melanogaster subgroup, and may be typical of the responses of African drosophilid populations to glacial cycles.  相似文献   

14.
The study on vegetation cover changes based on remote sensing data sources is an important component and frequent topic of earth surface process research. In order to review and summarize the remote sensing data sources and the spatio-temporal pattern of the study areas for vegetation cover changes in China from the perspective of bibliometrics and GIS spatial presentation, the information of remote sensing data sources and study areas were extracted from 1 021 papers on vegetation. Then the composition of remote sensing data sources and their temporal changes in heat which is termed as study frequency, the spatio-temporal scale characteristics of remote sensing data sources and study areas, and the distributions and change characteristics of hot study regions were analyzed. The results show that the number of papers is increasing gradually, and the frequency of each remote sensing data source is basically consistent with its available timing; the average period length of the remote sensing data used is gradually elongated, and the spatial resolution of remote sensing data is positively correlated with the size of study areas stably; the hot study regions are concentrated in the Loess Plateau area, and the core of the northern arid and semi-arid areas. These results can provide a basic reference for understanding the spatio-temporal pattern and the change trend on the utilization of remote sensing data sources and hot regions for vegetation change studies.  相似文献   

15.
青藏高原湖泊遥感信息提取及湖面动态变化趋势研究   总被引:5,自引:0,他引:5  
闫立娟  齐文 《地球学报》2012,33(1):65-74
青藏高原湖泊星罗棋布,是我国盐湖主要分布区.本文以RS和GIS技术为基础,从Landsat的MSS、TM、ETM三期遥感影像中,提取了青藏高原的所有湖泊信息,建立了我国盐湖空间数据库.用ArcGIS对盐湖空间数据进行统计和空间分析,从时间和空间上分析青藏高原从70年代到2000年左右湖泊湖面动态变化情况.同时,在青海和...  相似文献   

16.
人类活动影响下的胶州湾近百年来环境演变的沉积记录   总被引:13,自引:0,他引:13  
本文报道了胶州湾柱状沉积物中各生源要素(C、N、P、BSi)以及重金属(Cd、Cr、Pb、Cu、Ni、Co、Zn等)的地球化学特征,在210Pb精确定年的基础上计算了各项地球化学参数的埋藏通量,并结合元素间的比值(OC/TN、OC/OP、BSi/N、BSi/P;其中OC为有机碳,TN为总氮,OP为有机磷,BSi为生物源硅)和重金属的某些污染指数,给出了胶州湾环境演变的沉积记录以及人类活动影响因子.结果表明:胶州湾近百年的环境演变大致可以分为三个阶段:1980年以前、1980年到2000年左右和2000年至今,经历了环境的未受污染期污染期治理好转期.这些变化除与自然因素有关外,大部分应该归因于人类活动作用的加强.  相似文献   

17.
Urban expansion has become one of the main factors influencing natural habitats. Understanding the advances on the assessments of the impacts of urban expansion on natural habitats is of great significance to balance the contradiction between urban expansion and natural habitats protection and to improve urban sustainability. Therefore, this paper reviewed the assessments of the impacts of urban expansion on natural habitats. The results showed that the number of papers and the frequency of citations continuously increased. Previous studies mainly evaluated the impacts of urban expansion on natural habitats in broad sense, and emphasized the impacts on the area and spatial patterns of natural habitats. The scale of previous studies concentrated on the local scale, and the spatial statistics were used as the most popular assessment method. Previous studies have laid a good foundation for understanding the impacts of urban expansion on natural habitats, but there are shortcomings in several aspects of contents, scales and methods. To solve those shortcomings, we propose a framework for assessing the impacts of urban expansion on natural habitats based on the principle of "multiple perspectives, multiple scales, and multiple methods". This framework will be helpful to assess the impacts of urbanization on natural habitats in a more effective way.  相似文献   

18.
内蒙大青山全新世冰缘现象及环境演变   总被引:7,自引:2,他引:7  
崔之久  宋长青 《冰川冻土》1992,14(4):325-331
  相似文献   

19.
Yinhuang Irrigation District in Ningxia, as the top rice production area of high quality and quantity, has a long history in rice planting. The studies of the effective measures for the rice production replying the climate change were very important for reducing the harm of the future climate change and crop supply safety in Ningxia Province. Based on the coupling of the PRECIS model and the crop model CERES Rice, the effects of climate change on the rice production and growth stage in Yinhuang Irrigation District in Ningxia Province were simulated and evaluated, and the adaptability measures of rice production were studied. The results showed that the CERES Rice model had the preferable simulation capability, and the modified PRECIS model also could preferably simulate the required climate parameter. The crop model simulation results showed that the climate change had some influence on the rice production and growth stage in Yinhuang Irrigation District. The rice production goes down under future climate change scenarios in Ningxia Province. The trend of reduction of 2050s is more apparent than that of 2020s under the same scenarios,but the spatial change trend is similar. The extent and range of reduction of A2 scenario are wider than that of B2 scenario in the same period, but spatial change trend is different. For the change of growth stage, there has no obvious change in the north and the central part of the Yinhuang Irrigation District. The duration in 2050s shortens more obviously than that of 2020s under the same scenario, and the duration under B2 scenario shortens more obviously than that under A2 scenario in the same period. The results of adjusting the sowing date and the rice variety parameter G4 showed that the negative impact of climate change on the rice production can be reduced by sowing date advance in Yinhuang Irrigation District in Ningxia Province. There has obvious difference for the optimal G4 values of different region in Yinhuang Irrigation District, and the rice production can also be effectively upraised by adjusting the rice variety characteristic and cultivating the heat resistant rice varieties. The optimal G4 values can mitigate the damage of climate change on the rice production in Yinhuang Irrigation District in Ningxia Province.  相似文献   

20.
人类活动与气候变化对科尔沁沙质草地植被的影响   总被引:2,自引:0,他引:2  
1992—2006年在科尔沁沙地开展了草地放牧和封育试验,分析研究了人类放牧活动和气候变化对草地植被的影响。研究结果表明:①人类放牧活动对沙质草地植被具有显著影响,其中轻度放牧可使原退化草地植被盖度、高度、物种丰富度和多样性明显提高,中度放牧下虽然草地植被盖度和高度有所下降,但对物种丰富度和多样性无不良影响,持续过度放牧可以导致草地植被迅速破坏;②围栏封育可以促进退化草地植被盖度、高度、物种丰富度和植物多样性得到较快恢复,其恢复速度是草层高度>植被盖度>物种丰富度>多样性;③暖湿气候有利于草地维持较高的植被盖度、高度、物种丰富度和多样性,而持续干旱会导致相应指标的明显下降,多雨时期气温变化对植被的影响较大,干旱时期降水变化对植被的作用较强。  相似文献   

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