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1.
It is over 110 years since the term Mass Elevation Effect(MEE) was proposed by A. D. Quervain in 1904. The quantitative study of MEE has been explored in the Tibetan Plateau in recent years; however, the spatial distribution of MEE and its impact on the ecological pattern of the plateau are seldom known. In this study, we used a new method to estimate MEE in different regions of the plateau, and, then analyzed the distribution pattern of MEE, and the relationships among MEE, climate, and the altitudinal distribution of timberlines and snowlines in the Plateau. The main results are as follows:(1) The spatial distribution of MEE in the Tibetan Plateau roughly takes on an eccentric ellipse in northwestsoutheast trend. The Chang Tang Plateau and the middle part of the Kunlun Mountains are the core area of MEE, where occurs the highest MEE of above 11℃; and MEE tends to decreases from this core area northwestward, northeastward and southward;(2) The distance away from the core zone of the plateau is also a very important factor for MEE magnitude, because MEE is obviously higher in the interior than in the exterior of the plateau even with similar mountain base elevation(MBE).(3) The impacts of MEE on the altitudinal distribution of timberlines and snowlines are similar, i.e., the higher the MEE, the higher timberlines and snowlines. The highest timberline(4600–4800 m) appears in the lakes and basins north of the Himalayas and in the upper and middle reach valleys of the Yarlung Zangbo River, where the estimated MEE is 10.2822℃–10.6904℃. The highest snowline(6000–6200 m) occurs in the southwest of the Chang Tang Plateau, where the estimated MEE is 11.2059°C–11.5488℃.  相似文献   

2.
秦巴山地是中国的南北分界线,也是黄河和长江的分水岭,其山体效应的定量化影响秦巴山地山体垂直带的分布格局、非地带性因素的作用强度和机理,以及中国暖温带和北亚热带的具体位置的确定。山体基面高度是影响山体效应最重要和关键的地形因子,其定量化和数字化提取是秦巴山地山体效应定量化研究的重要内容。本研究针对秦巴山地山体效应的定量化研究,使用30 m分辨率的STRM-1数据,分别基于山体特征线和流域分区2种方法提取了秦巴山地的山体基面高度分区,并根据地形起伏度和坡度,确定基面范围,计算了山体基面高度值。结果表明:① 基于山体特征线的方法将秦巴山地分为93个基面高度分区,基于流域分区的方法将秦巴山地分为209个基面高度分区,根据2种分区结果提取的基面高度值相差不大且均体现了秦巴山地地势的特点;② 秦巴山地山体基面高度从东向西呈阶梯状递增的趋势;③ 从南到北,秦巴山地的东段和中段均呈先增高后降低的趋势,即从大巴山向北至汉江谷地降低,再向北至秦岭升高;④ 山地的不同侧翼的山体基面高度不同,秦岭南坡的基面高度(1000~1809 m)明显高于北坡(850~1300 m)。秦巴山地山体基面高度与其植被带分布上限联系密切,实现山体基面高度的数字化提取,为山体效应的定量化研究提供了重要的技术支持。  相似文献   

3.
分析了技术要素按贡献参与分配的基本依据和存在问题 ,提出了技术要素按贡献参与分配的建议 :1.在企业分配领域 ,鼓励技术要素以多种形式参与收益分配 ,鼓励体制创新 ,推进技术股份化。 2 .在政府分配领域 ,政府财政科技投入比例与其科技发展对经济贡献增长率挂钩 ,科技财税政策与产业政策、税源经济吻合 ,营造科技奖励的软环境。 3.在社会分配领域 ,充分发挥技术评估部门和行业管理部门的作用 ,对进入技术市场的技术的成熟度和科技含量进行有效的测试和监管 ,保证技术商品的品质 ;技术交易当事人应具诚信态度和法制观念 ;重视中介的作用 ,把技术市场搞活。  相似文献   

4.
利用国际上常用的8个冰川均衡调整(GIA)模型分别对利用卫星重力(GRACE)数据解算的2005~2014年全球质量变化趋势进行GIA改正。在对南极地区进行改正时发现,ICE-6G_C、ICE-6G_D和IJ05这3种模型的改正值相近;在对全球海水质量变化趋势进行改正时发现,不同改正模型对全球海水质量变化影响的均值都小于-2.0 mm/a;对比陆地水及冰盖对海水质量变化趋势的贡献,同时联合卫星测高和Argo温盐数据集进一步验证发现,Paulson07、GW13和ICE-6G_D模型对全球海水质量改正效果较好。综合整个陆地和海洋的分析结果来看,ICE-6G_D模型更适用于全球质量变化趋势的调整。  相似文献   

5.
Based on the simulation with SWAN wave model and data of ERA-Interim from 1979 to 2016, how the waves propagate globally and why swell pools distribute in the eastern ocean were investigated in this study. The simulation results show that waves from North Pacific and North Atlantic mainly propagate southeastward or southward and swells generated in Southern Ocean spread northeastward. The waves from high latitude regions spread along the east coast and encounter in the tropical Pacific and Atlantic to form swell fronts around equator and then turn eastward. As the weak wind field with numerous swell inflows, swell pools are generally located on the eastern side of the ocean basin, where the swell index S are greater than 0.9 calculated using ERA-20 C data for the period of 1981–2010. Another remarkable feature is that swell pools move southward and split into two parts in winter, while they move northward and merge together in summer.  相似文献   

6.
7.
1 PresentSituationofResearchforGlobalClimateRecently ,theresearchfortheglobalclimatechangescausedbytidehasachievedremarkableresul  相似文献   

8.
The differential rotation between the solid and fluid spheres caused by tidal force could explain the 1500 to 1800-year cycle of the world's temperature. Strong tide increases the vertical and horizontal mixing of water in the oceans, drawing the cold Pacific water from the depths to the surface and the warm water from the west to the east, where it cools or warms the atmosphere above, absorbs or releases CO2 to decrease or increase greenhouse effect and to make La Nina or El Nino occur in the global. The moon's declination and obliquity of the ecliptic affect the tidal intensity. The exchange of tidal energy and tide-generating force caused by the sun, moon and major planets makes the earth's layers rotate in different speeds. The differenti-al rotation between solid and fluid of the earth is the basic reason for El Nino and global climate change.  相似文献   

9.
The Effect of Tide on the Global Climate Change   总被引:1,自引:0,他引:1  
The differential rotation between the solid and fluid spheres caused by tidal force could explain the 1500 to 1800 - year cycle of the worlds temperature. Strong tide increases the vertical and horizontal mixing of water in the oceans,dra-wing the cold Pacific water from the depths to the surface and the warm water from the west to the east, where it cools or warms the atmosphere above, absorbs or releases CO2 to decrease or increase greenhouse effect and to make La Nina or El Nino occur in the global. The moons declination and obliquity of the ecliptic affect the tidal intensity. The exchange of tidal energy and tide -generating force caused by the sun, moon and major planets makes the earths layers rotate in different speeds. The differenti-al rotation between solid and fluid of the earth is the basic reason for El Nino and global climate change.  相似文献   

10.
The global monsoon(GM) comprises two major modes, namely, the solstitial mode and equinoctial asymmetric mode.In this paper, we extend the GM domain from the tropics to the global region and name it the global spring – autumn monsoon(GSAM), which mainly indicates a spring–autumn asymmetrical precipitation pattern exhibiting annual variation. Its distribution and possible formation mechanisms are also analyzed. The GSAM domain is mainly distributed over oceans, located both in the midlatitude and tropical regions of the Pacific and Atlantic. In the GSAM domains of both the Northern and Southern Hemispheres, more precipitation occurs in local autumn than in local spring. The formation mechanisms of GSAM precipitation vary according to the different domains. GSAM precipitation in the tropical domain of the Eastern Hemisphere is influenced by the circulation differences between the onset and retreat periods of the Asian summer monsoon, while tropical cyclone activities cause precipitation over the South China Sea(SCS) and western North Pacific(WNP). GSAM precipitation in the tropical domain of the Western Hemisphere is influenced by the tropical asymmetrical circulation between the Northern and Southern Hemispheres and the variation in the intertropical convergence zone(ITCZ) driven by the intensity of the sea surface temperature cold tongues over the equatorial eastern Pacific and eastern Atlantic. GSAM precipitation in the midlatitude domain is influenced by the differences in water vapor transportation and convergence between spring and autumn. In addition, GSAM precipitation is also affected by extratropical cyclone activities.  相似文献   

11.
Oceanic contribution to the poleward heat flux in the climate system includes two components: the sensible heat flux and the latent heat flux. Although the latent heat flux has been classified as atmospheric heat flux exclusively, it is argued that oceanic control over this component of poleward heat flux should play a critically important role. The so-called swamp ocean model practice is analyzed in detail, and the critical role of oceanic circulation in the establishment of the meridional moisture transport is emphasized.  相似文献   

12.
Oceanic contribution to the poleward heat flux in the climate system includes two components: the sensible heat flux and the latent heat flux. Although the latent heat flux has been classified as atmospheric heat flux exclusively, it is argued that oceanic control over this component of poleward heat flux should play a critically important role. The so-called swamp ocean model practice is analyzed in detail, and the critical role of oceanic circulation in the establishment of the meridional moisture transport is emphasized.  相似文献   

13.
Earthquakes exhibit clear clustering on the earth. It is important to explore the spatial-temporal characteristics of seismicity clusters and their spatial heterogeneity. We analyze effects of plate space, tectonic style, and their interaction on characteristic of cluster.Based on data of earthquakes not less than moment magnitude(M_w) 5.6 from 1960 to 2014, this study used the spatial-temporal scan method to identify earthquake clusters. The results indicate that seismic spatial-temporal clusters can be classified into two types based on duration: persistent clusters and burst clusters. Finally, we analysed the spatial heterogeneity of the two types. The main conclusions are as follows: 1) Ninety percent of the persistent clusters last for 22-38 yr and show a high clustering likelihood;ninety percent of the burst clusters last for 1-1.78 yr and show a high relative risk. 2) The persistent clusters are mainly distributed in interplate zones, especially along the western margin of the Pacific Ocean. The burst clusters are distributed in both intraplate and interplate zones, slightly concentrated in the India-Eurasia interaction zone. 3) For the persistent type, plate interaction plays an important role in the distribution of the clusters’ likelihood and relative risk. In addition, the tectonic style further enhances the spatial heterogeneity. 4) For the burst type,neither plate activity nor tectonic style has an obvious effect on the distribution of the clusters’ likelihood and relative risk. Nevertheless,interaction between these two spatial factors enhances the spatial heterogeneity, especially in terms of relative risk.  相似文献   

14.
采用两种方式得到2011年日本东北大地震引起的洋底垂直形变数据,通过傅里叶变换和傅里叶逆变换计算得到洋底地壳垂直运动产生的洋底地壳与海水物质交换导致的重力效应。分析这两种方式得到的重力变化并与利用GRACE提取的重力变化对比,结果发现此效应显著,在提取同震重力变化时不可忽略。  相似文献   

15.
受社会制度变迁和气候变化的影响,哈萨克斯坦是中亚地区生态退化和草畜矛盾问题最为突出的国家。近百年来,放牧方式的改变、农业开垦的占用、加之暖干化的气候变化影响,使得哈萨克斯坦各类草地生态系统变化的时空格局具有鲜明的特点。因此,研究哈萨克斯坦草地退化的过程与机制对认识中亚地区草地生态系统对气候变化和人类活动的响应尤为重要,也是对绿色丝路建设过程中区域生态可持续发展的科学支撑。土地覆被数据是生态变化研究的基础数据,但目前广泛使用的各套全球数据集间往往存在很大的差异,这会导致对生态变化成因的认知以及对未来变化的模型模拟产生更大的不确定性。本研究从对草地类型识别的定义、空间分布的一致性和空间分布差异的原因3方面对比5类全球土地覆被数据(UMD 1992-1993、MCD12Q1 2001、GLC 2000、CCI-LC 2000、Glob Cover 2005)中哈萨克斯坦草地分布的异同,以期为哈萨克斯坦的相关研究中土地覆被数据集的选择提供依据。研究结果表明:① 分类系统中对草地类型的界定、遥感数据源、辅助分类数据、分类方法、验证数据和方法的不同是5套数据草地资源分布差异的主要原因,其中MCD12Q1数据与其他4套数据的草地分布面积相差最大;② 5套数据中草地分布都重叠(完全一致)或四套数据重叠(高度一致)的区域仅占39.66%,主要位于哈萨克斯坦典型草原带和部分半荒漠草原带;围绕典型草地分布区,空间一致性由内向外逐渐降低。5套数据完全不一致区域占26.78%,主要位于荒漠草原带;③ CCI-LC2000数据与其他几类数据的重叠区域最高,有76%的草地与5套数据的完全一致以及高度一致区重叠;在分布不一致区域中,极易造成混淆的土地覆被类型主要为旱作耕地、灌溉耕地、耕地与自然植被镶嵌体、裸地以及灌丛。  相似文献   

16.
利用谷歌三维地图勾绘出全球海底现今主要断层构造带的分布图,为观察海洋地壳运动与演化过程提供新的方法和视角,对海底活断层的分布和演化机理、海底扩张、地幔对流等方面的深入研究和探索具有重要意义。  相似文献   

17.
阐述了最小二乘配置基本原理,给出在吉洪诺夫条件下的最小二乘解和一种新的确定经验协方差的方法,并通过实例讨论信号与噪声权的选择对GPS高程拟合精度的影响。结果表明,随着信号与噪声权比的增大,内符合精度明显提高,检核精度也有一定的提高。  相似文献   

18.
欧亚大陆山地垂直带数字集成系统的设计与应用   总被引:1,自引:0,他引:1  
在欧亚大陆山地垂直带880个带谱点数据采集的基础上,设计和开发了山地垂直带数字集成系统。其功能:(1)垂直带谱可视化显示功能:实时生成垂直带地理分布图、垂直带堆积柱状图、上下限高度随经纬度变化曲线;(2)垂直带上下限提取和绝对高度和相对高度转化功能:提取山地垂直自然带分布上限和下限高度,进行垂直带的宽度和垂直带上限海拔...  相似文献   

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20.
以2006年8月在长江口外海域海试的悬浮泥沙数据资料为基础,采用相关分析和非线性回归分析方法,通过在经典泥沙剖面模型中引入潮流等过程的影响,改进了泥沙剖面模型的预测效果,将仅受水深一个因素控制的泥沙剖面模型拓展为与不同地点水文物理过程相关联的实用模型,并在整个研究区域验证了模型的有效性。  相似文献   

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