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1.
城市绿地的小气候效应空间差异性——以大连市为例   总被引:2,自引:0,他引:2  
基于大连市气候指标与绿地进行的相关分析,并根据其城市小气候观测结果发现:城市绿地的气候调节效应在市区范围影响微弱,然而在市内局部区域上表现突出,即绿地对城市小气候调节效应存在着空间差异性;进一步分析表明,其原因在于绿地自身不够完善--绿地面积少、分布不均、结构不合理等问题,加之城市化进程加快,一定程度上抵消了绿地的降温增湿效应.  相似文献   

2.
博斯腾湖流域山区地表径流对近期气候变化的响应   总被引:4,自引:0,他引:4  
近年来,在全球和区域气候变化影响下,新疆博斯腾湖主要产流区开都河出山径流呈现异常波动,引起气候变化研究的关注.鉴于产流区复杂地形和径流补给特征以及传统观测资料的不足,借助雷达、微波及可见光等多源遥感数据从山区降水、积雪和冰川等方面与出山径流变化关系进行比较来揭示径流突变原因.结果表明,产流区平均径流深与降水量关系的转变是引起出山径流异常波动直接原因;进一步的冰川变化分析显示,径流深的波动主要由冰川融水径流变化引起:20世纪80年代中期后的温度上升加速了山顶冰川消融,导致1987~2002年的径流增加和湖泊水位升高;1984~2000年间,流域山顶冰川面积消退近40%,随着分布在较低海拔,对温度升高最敏感的中小冰川的消失,冰雪消融带来的径流增加效应开始减弱;2002年后,在流域气温、降水等变化并不显著的情况下,出山径流量却急剧降低,反映了特定冰川分布条件地区在气候变暖中融水径流先升后降的现象.  相似文献   

3.
李学东 《极地研究》1992,4(3):52-57
198 9年 2月 1— 1 0日 ,对南极乔治王岛菲尔德斯半岛长城站附近的苔藓小气候进行了初步考察、观测和分析 ,并与长城站相应时间的常规记录进行了比较 ,初步揭示了南极地区苔藓小气候方面值得引起注意的某些特征。  相似文献   

4.
基于2007年7~9月对科其喀尔冰川消融区冰面湖、表碛、裸冰的温度和消融观测,分析三者的温度变化特征及其差异,探讨冰面湖的热机制.结果表明:科其喀尔冰川冰面湖表层水温受瞬时天气状况影响明显,变化趋势与气温一致,但不如气温变化剧烈并有1~3h滞后性;由于白天冰川融水注入与表层暖水混合下沉,深层湖水在一天的14~16时左右...  相似文献   

5.
高山增水效应及其水资源意义   总被引:9,自引:1,他引:9  
丁贤荣 《山地学报》2003,21(6):681-685
根据高山上云、雾、雨、雪、径流等水资源丰富现象,分析了高山冰川、植被、地形等与汽-水作用关系,提出高山增水效应概念和高山区水资源开发与保护的新思路。高大山体及其造成的垂向对流、高山冰川和高山植被共同作用形成了高山增水效应,并形成良性增水系统。山体愈高大,增水效应愈明显。对内陆干旱地区开发利用更多的高山水资源具有意义。  相似文献   

6.
冰川终碛湖溃决引发的大规模山洪泥石流灾害,常给下游沿河一带造成重大人员伤亡和财产损失,受到社会广泛关注。冰川终碛湖一次溃决常未到底,其部分溃决后,残留湖因源头冰川进退、冰舌持续消融致后期湖面面积增大,湖水量增加,作者将这种现象定义为冰川终碛湖溃决-再生现象。以西藏波密米堆沟光谢错和聂拉木章藏布次仁玛错冰湖为研究对象,基于前人研究成果,利用遥感解译方法,分析了光谢错和次仁玛错冰湖面积的变化和冰川末端进退变化的特征。研究表明:光谢错、次仁玛错呈现出冰湖面积增大→溃决缩小→面积再增大的过程,光谢错在1988年溃决后面积已恢复至溃决前的63.6%,次仁玛错在1981年溃决后面积已基本恢复至溃决前的大小;从1980年代末至现在,贡扎冰川、阿玛次仁冰川末端处于退缩状态,终碛湖面积呈扩张状态。结合波密、聂拉木两气象站多年年降水量和年平均气温观测资料进行同步对比分析,初步探讨了冰川终碛湖再生现象的机理:1.冰川末端的前进与后退是冰湖面积变化的主导者,冰舌前进推动湖盆底冰碛物和溃口两侧岸坡垮塌导致堵塞泄流通道,冰川末端的退缩提供了空间条件;2.持续高温与强降雨的耦合作用是冰湖溃决的直接激发条件,持续高温累积是冰川消融冰湖面积增大的主要因素。  相似文献   

7.
纳木错流域冰川和湖泊变化对气候变化的响应   总被引:7,自引:0,他引:7  
利用纳木错流域及其周边地区气象资料、地形图、遥感资料以及野外实地观测资料,对该流域过去37年来气候变化特征以及冰川、湖泊变化过程进行了分析.结果表明,自1970年以来,纳木错区域气温上升趋势明显,其中冬季升温幅度高于夏季;降水量变化冬、夏两季均呈增加趋势,但冬季增加量不显著.在整体升温的背景下,纳木错流域冰川整体呈退缩趋势.1970~2007年间,流域内冰川面积减少37.1 km~2,占流域冰川面积的18.2%,年变化率为-1.0 km~2/a.流域内扎当冰川和拉弄冰川末端GPS观测表明,1970~2008年间冰川末端分别退缩381.8 m和489.5 m,年均退缩量为10.3 m和13.4 m.1970-2007年间,纳木错湖面积增加了72.6 km~2,增加速率为2.0 km~2/a.1970-1991年、1991-2000年和2000-2007年三个阶段的年增加速率不断增大,分别为1.1、2.8、3.4 km~2/a;湖泊水在在夏季升高非常显著,与湖泊面积的扩张是一致的.  相似文献   

8.
海岸沙地防护林的小气候效应   总被引:13,自引:2,他引:11  
谢平  李燕 《中国沙漠》2001,21(1):93-96
对广东省湛江市东海岛海岸沙地防护林林内与林外的光照、温度、湿度及风速等气象因子进行对比观测,结果表明,防护林林内光照强度减弱、温度变化缓和、湿度增加、风速减小,小气候效应显著,改善了海岸沙地的生态环境。  相似文献   

9.
天山奎屯河哈希勒根51号冰川变化监测结果分析   总被引:2,自引:1,他引:1  
哈希勒根51号冰川位于新疆奎屯市以南的天山依连哈比尔尕山北坡,即奎屯河上游支流哈希勒根河源区。1999年8月,在该冰川上布设了用于冰川变化观测研究的测杆18根;同时,在冰川外围测定了2个基本控制点和3个冰川末端变化观测控制点,运用GPS和全站仪等观测技术及测杆实测等方法,对该冰川进行了末端和运动速度变化的首次观测。嗣后,每年的8月底~9月初进行了重复观测;并在2000年和2006年对该冰川进行了测量制图。通过实测资料分析并对比20世纪60年代冰川状况,结果表明:42年来冰川末端累计退缩了84.51 m,其中,1964-1999年间退缩了49.00 m,年平均退缩量为1.40 m/a;1999-2006年间退缩了35.51 m,年平均退缩量5.07m/a。冰川面积减少了0.123 km~2或8.3%,其中,1964-2000年间减少了0.083 km~2;2000-2006年间减少了0.040 km~2。明显地反映出冰川末端退缩加剧和冰川面积减少增大的趋势。冰川年平均运动速度在1.53~3.05 m/a之间,并有逐年减小的趋势。  相似文献   

10.
冰川作用区的温度及其特征   总被引:5,自引:0,他引:5  
康兴成 《地理学报》1993,48(2):152-160
本文通过西昆仑山崇侧冰川区的观测资料。揭示了冰川区和非冰雪区气温的日变化,垂直和水平方向的摘变以及季节变化。结果表明,冰雪区气温的日变化小,而昼夜温差大,全天均为绝热稳定区。非冰雪区白天为绝热不稳定状态,夜晚存在逆温现象。接近冰雪区地带气温递减率较大。水平方向温差主要发生在冰雪区前缘地带。由此,提出了冰川区特有的现象——“冰川锋”,并给出了该地区作为青藏高原最冷区域之一的一些数值。  相似文献   

11.
冰川冰储量不仅是冰川的重要属性,而且是核算冰川水资源及预测冰川变化的基础数据,因此准确计算冰川冰储量及其变化具有重要的理论与现实意义。目前冰川储量估算的主要方法有经验公式法、冰厚模型估算法、探地雷达法;冰川储量相对变化计算方法有实地测量法和遥感监测法。通过系统分析和讨论各计算方法的原理、现状及存在的问题,以期为冰川储量估算提供方法参考。研究表明:对于冰川冰储量计算而言,经验公式法适用于区域性或全球性的冰川储量估算;模型估算法适用于个体或小范围冰川储量估算;探地雷达法适用于人类易到达区域冰川储量的估算。对于冰川冰储量相对变化计算,实地测量法适用于对精度要求高且满足实地测量条件的单条或中小型冰川,遥感监测法适用于全球性冰储量变化估算,但需改进算法和提高数据空间分辨率。目前,随着无人机技术的逐步应用,以及冰川流速等理论模型的提出,为冰川冰储量估算方法的发展提供了新契机。  相似文献   

12.
Snowpacks samples were colleted from two glaciers: Baishui No.1 glacier and Hailuogou No.1 glacier in June, 2006. The method of sea-salt ions tracer, correlation analysis and trend analysis were used in this research in order to confirm the source of main ions, it is indicated that Na+ is mainly from marine moisture and other ions mainly originate from land dust. The non-marine source percent of Cl-, NO-3, SO2-4, K+, Ca2+ and Mg2+ is 52%, 99%, 100%, 98%, 99.9% and 83%, respectively, in Hailuogou No.1 glacier, while the corresponding value in Baishui No.1 glacier is 68%, 99%, 100%, 98%, 99% and 59%. The non-marine source of ions is from dust of Central Asia arid regions carried by westerly circulation and the plateau borne-areas with Qinghai-Tibet Plateau winter monsoon in two glacial areas. How-ever, the import of local dust in glacial area has made a great contribution to ions concentra-tion in Baishui No.1 glacier, which accounts for the reason why the ions concentration in Bai-shui No.1 glacier is much higher than that of Hailuogou No.1 glacier. It is obvious that the source of each ion is different between Hailuogou No.1 glacier and Baishui No.1 glacier. There are three reasons which can explain it: firstly, the difference in the internal environment of glacial area, such as lithology, mountain-valley wind system, topographical relief and so on; secondly, the influence exerted by ions elution in snowpacks section, and ions elution in Hailuogou No.1 glacier is very strong; and thirdly, the difference caused due to varying ions transporting styles, deposition modes, chemical characteristics and post-ions-deposition process.  相似文献   

13.
Snowpacks samples were colleted from two glaciers: Baishui No.1 glacier and Hailuogou No.1 glacier in June, 2006. The method of sea-salt ions tracer, correlation analysis and trend analysis were used in this research in order to confirm the source of main ions, it is indicated that Na^+ is mainly from marine moisture and other ions mainly originate from land dust. The non-marine source percent of Cl^-, NO3^- , SO4^2-, K^+, Ca^2+ and Mg^2+ is 52%, 99%, 100%, 98%, 99.9% and 83%, respectively, in Hailuogou No.1 glacier, while the corresponding value in Baishui No.1 glacier is 68%, 99%, 100%, 98%, 99% and 59%. The non-marine source of ions is from dust of Central Asia arid regions carried by westerly circulation and the plateau borne-areas with Qinghai-Tibet Plateau winter monsoon in two glacial areas. However, the import of local dust in glacial area has made a great contribution to ions concentration in Baishui No.1 glacier, which accounts for the reason why the ions concentration in Baishui No.1 glacier is much higher than that of Hailuogou No.1 glacier. It is obvious that the source of each ion is different between Hailuogou No.1 glacier and Baishui No.1 glacier. There are three reasons which can explain it: firstly, the difference in the internal environment of glacial area, such as lithology, mountain-valley wind system, topographical relief and so on; secondly, the influence exerted by ions elution in snowpacks section, and ions elution in Hailuogou No.1 glacier is very strong; and thirdly, the difference caused due to varying ions transporting styles, deposition modes, chemical characteristics and post-ions-deposition process.  相似文献   

14.
1959年来中国天山冰川资源时空变化   总被引:1,自引:0,他引:1  
基于两期冰川编目数据与气象数据,对天山1959年来冰川资源的时空变化特征进行研究。研究发现:① 天山地区现有冰川7934条,面积7179.77 km2,冰储量756.48 km3。冰川数量以面积< 1 km2的冰川居多,面积以1~10 km2和≥ 20 km2的冰川为主,冰川集中分布在海拔3800~4800 m之间。② 在四级流域中,阿克苏河流域冰川面积最大为1721.75 km2,面积最小的是伊吾河流域,为56.03 km2。在各市(州)中,阿克苏地区冰川资源量最多,其面积和储量分别占天山总量的43.28%和68.85%;冰川资源量最少的市(州)是吐鲁番地区,面积和储量仅占天山总量的0.23%和0.07%。③ 1959年来,天山地区冰川面积减少了1619.82 km2(-18.41%),储量亏损了104.78 km3(-12.16%),其中数量以< 1 km2的冰川减少最多,面积减少以< 5 km2的冰川最为严重。④ 冰川变化呈现明显的区域差异,变化速度最快的是天山东段博格达北坡流域,变化最慢的是中部的渭干河流域。初步分析认为夏季气温显著上升带来的消融大于年内降水带来的积累是天山冰川退缩的主要原因。  相似文献   

15.
利用面向对象分类方法,从Landsat影像中提取了1990年、2000年、2010年、2015年4期布喀达坂峰地区冰川空间分布数据,并利用GIS技术分析研究区最近25 a来冰川变化,探讨了冰川对气候变化的响应关系。结果表明:布喀达坂峰冰川总面积退缩了7.28 km2,退缩速率为0.29 km2·a-1,占1990年的1.78%,且1990-2000年、2000-2010年、2010-2015年各个时段内冰川退缩速率呈较快-快-慢的状态,不同朝向的冰川退缩速率略有差异,南坡山谷冰川退缩速率最快,北坡坡面冰川次之,中段平顶冰川退缩速率最慢;冰川表面运动速度沿中流线向冰川侧脊和冰川末端递减,符合冰川运动一般规律,而不同类型的冰川其表面运动速度的时空变化具有差异性。研究发现,夏季均温的显著升高和年降水量的缓慢增加的共同作用是引起布喀达坂峰冰川退缩的主要原因。此外,地势条件和冰川自身结构等因素对冰川变化的作用也不容忽视。  相似文献   

16.
阿尔泰山冰川系统结构、近期变化及趋势预测   总被引:4,自引:0,他引:4  
地跨中、俄、哈、蒙四国的阿尔泰山共有冰川面积约1 700 km2,其中中国约280 km2,俄罗斯及哈萨克斯坦约880 km2,可作为统一的冰川系统进行研究.本文首先应用中国及前苏联冰川编目数据分析了本系统冰川的结构特征.表明本区冰川平衡线约为2 983 m,为中国的小型冰川(平均面积0.8 km2)作用区.应用最新的...  相似文献   

17.
冰川运动控制着冰量输送变化,为冰川变化和冰川灾害研究提供重要信息。为了探讨东帕米尔高原冰川运动特征及其影响因素,基于ITS_LIVE和GoLIVE分析了不同规模、不同地形条件、表碛/非表碛区域的冰川运动速度状况。研究结果表明:(1)东帕米尔高原冰川平均运动速度为5.31 m·a^-1,冰川运动速度与冰川规模相关,表现为大冰川比小冰川运动快;(2)冰川运动速度与平均坡度相关,表现为随平均坡度增加先增后减,坡度过大不利于冰川积累,表现为厚度(规模)小,则速度慢。(3)西南(8.69 m·a^-1)、东南(11.67 m·a^-1)坡向的冰川运动速度大于其它坡向的冰川运动速度,与各个坡向的冰川规模相关。(4)表碛覆盖型冰川的运动速度小于非表碛覆盖型冰川,表碛对冰川运动速度起到抑制作用。(5)1989-2018年东帕米尔高原冰川运动速度表现稳定,与冰川年际变化稳定相对应。消融期冰川运动速度小于其它季节,与年内冰川厚度变化相关。  相似文献   

18.
The Sachette rock glacier is an active rock glacier located between 2660 and 2480 m a.s.l. in the Vanoise Massif, Northern French Alps (45° 29′ N, 6° 52′ E). In order to characterize its status as permafrost feature, shallow ground temperatures were monitored and the surface velocity measured by photogrammetry. The rock glacier exhibits near‐surface thermal regimes suggesting permafrost occurrence and also displays significant surface horizontal displacements (0.6–1.3 ± 0.6 m yr–1). In order to investigate its internal structure, a ground‐penetrating radar (GPR) survey was performed. Four constant‐offset GPR profiles were performed and analyzed to reconstruct the stratigraphy and model the radar wave velocity in two dimensions. Integration of the morphology, the velocity models and the stratigraphy revealed, in the upper half of the rock glacier, the good correspondence between widespread high radar wave velocities (>0.15–0.16 m ns–1) and strongly concave reflector structures. High radar wave velocity (0.165–0.170 m ns–1) is confirmed with the analysis of two punctual common mid‐point measurements in areas of exposed shallow pure ice. These evidences point towards the existence of a large buried body of ice in the upper part of the rock glacier. The rock glacier was interpreted to result from the former advance and decay of a glacier onto pre‐existing deposits, and from subsequent creep of the whole assemblage. Our study of the Sachette rock glacier thus highlights the rock glacier as a transitional landform involving the incorporation and preservation of glacier ice in permafrost environments with subsequent evolution arising from periglacial processes.  相似文献   

19.
Data of 44 glacier systems in China used in this paper were obtained from Chinese Glacier Inventories and the meteorological data were got from Meteorological Atlas of Plateau of west China. Based on the statistical analysis and functional model simulation results of the 44 glacier systems in China, the glacier systems were divided into extremely-sensitive glacier system, semi-sensitive glacier system, extremely-steady glacier system and semi-steady glacier system in terms of glacier system’s level of water-energy exchange, rising gradient of the equilibrium line altitudes and retreating rate of area to climate warming, their median size and vertical span distribution, and their runoff characteristics to climate warming. Furthermore, the functional model of glacier system to climate warming was applied in this paper to predict the average variation trends of the 4 types of glacier systems, which indicate that different sensitivity types of glacier systems respond to the climate warming differently.  相似文献   

20.
中国冰川系统对气候变化响应的敏感性分析   总被引:5,自引:1,他引:4  
Data of 44 glacier systems in China used in this paper were obtained from Chinese Glacier Inventories and the meteorological data were got from Meteorological Atlas of Plateau of west China. Based on the statistical analysis and functional model simulation results of the 44 glacier systems in China, the glacier systems were divided into extremely-sensitive glacier system, semi-sensitive glacier system, extremely-steady glacier system and semi-steady glacier system in terms of glacier system's level of water-energy exchange, rising gradient of the equilibrium line altitudes and retreating rate of area to climate warming, their median size and vertical span distribution, and their runoff characteristics to climate warming. Furthermore the functional model of glacier system to climate warming was applied in this paper to predict the average variation trends of the 4 types of glacier systems, which indicate that different sensitivity types of glacier systems respond to the climate warming differently.  相似文献   

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