天山托木尔峰科其喀尔巴西冰川表面运动速度特征分析

天山托木尔峰科其喀尔巴西冰川是典型的树枝状山谷冰川,利用3组(6期)ASTER遥感影像通过COSI-corr软件反演了该冰川表面运动速度.与花杆测量数据进行对比,反演冰川表面运动速度平均绝对误差为3.1 m·a-1,相对误差为11.9%,二者在空间上的分布基本一致,表明其反演精度符合要求.在此基础上,分析冰川表面运动速...     

科其喀尔冰川表碛区冰崖形态调查

采用随机抽样的方法对科其喀尔冰川表碛区冰崖的规模及形态进行了调查.在冰崖比较集中的表碛区东侧任意选取了20个冰崖,利用测绳、皮尺并结合GPS测量的方法对冰崖的长度和高度进行了调查,同时用地质罗盘对冰崖的坡向和坡度进行了测量,从而了解冰崖的长度、高度、坡面面积、坡向和坡度等形态特征及其关系.对冰崖形态的分析表明,消融区内冰崖的规模相差很大,且随着海拔高度的增加,冰崖规模有减小的趋势;这可能主要与地形起伏随海拔高度的差异性变化有关,消融区下部冰崖表面消融过程较为活跃也是一个重要的因素.通过对冰崖的坡向和规模之间的分析可以看到,坡向为NW和NNE方向的冰崖最多,其规模也较大,而太阳直接辐射是影响冰崖发育坡向和发育规模的重要因素.     

天山南坡科其喀尔冰川消融区运动特征分析

基于2009年5月至2011年10月科其喀尔冰川的花杆观测资料,对其消融区的表面运动特征进行分析. 结果表明：冰川消融区的年水平运动速度最大值为86.69 m·a^-1,年垂直运动速度最大值为15.34 m·a^-1,均出现在冰川海拔4 000~4 200 m的消融区上部;在靠近冰川末端的冰舌下部,受冰量补给减弱、厚层表碛覆盖等影响,冰川运动缓慢,年水平运动速度小于5 m·a^-1,而垂直运动速度值小于2 m·a^-1. 大多数横剖面的水平运动速度具有从中部向边缘逐渐减小的特征,而有的剖面却出现局部速度增大的区域. 整体而言,冰川水平及垂直运动速度随海拔降低而减小,符合冰川运动的一般规律,但主要受地形作用的影响,垂直运动速度随海拔的变化会出现波动. 消融期月水平运动速度与同期气温和降水的变化具有一定的相关性,可能反映出气候快速变化对冰川运动的影响.     

科其喀尔冰川表碛区冰崖消融的度日因子研究

度日因子.冰崖坡向的变化也对度日因子产生了影响,总体表现为NEE-SE方向及SW-W方向的度日因子较大,NWW-N-NE方向的较小,S方向的最小,这主要与该地区的辐射、气温等气象条件的变化特征有关.研究还表明,冰崖的坡度对度日因子的影响较小.     

西天山托木尔峰南麓大型山谷冰川冰舌区消融特征分析

基于对托木尔峰南麓托木尔型山谷冰川的野外考察和典型冰川的定位观测,对冰面被表碛广泛覆盖的所谓“托木尔型”冰川冰舌区表碛与冰面消融的关系进行了研究. 结果表明：表碛对冰面消融、冰川水文过程、冰川变化等均具有重要影响,当表碛厚度超过3 cm时,表碛对冰面消融就产生明显抑制作用,且随着厚度增加,冰面消融显明减弱. 科其喀尔冰川表面的观测表明,由末端向上,表碛厚度逐渐减薄. 受表碛影响,科其喀尔冰川区最大的消融量出现在海拔3 800~3 900 m之间、表碛物厚度小于10 cm的区域内;冰川消融强度由此向上随着海拔的升高而下降,向下随表碛厚度的增大而减弱. 冰面湖的发育是表碛覆盖冰川的又一主要特征,湖水对冰面的融蚀和快速排泄成为冰面产汇流的主要过程. 科其喀尔冰川研究表明,两三个冰面湖排泄形成的融蚀冰量就相当于冰川末端退缩造成的冰量损失. 因此,冰面湖等热喀斯特地形的形成、扩张融蚀、融穿排泄、形成湖区低地,这一周而复始的过程不仅是其主要消融方式之一,而且也强烈的影响着冰川水文及冰川变化. 托木尔峰南麓地区大型冰川变化主要以厚度减薄为主,而不是像大多数冰川显著的变化主要表现在末端和面积减少方面.     

科其喀尔巴西冰川的近地层基本气象特征

利用2003-2006年天山托木尔峰地区科其喀尔巴西冰川的考察资料,对该冰川近地层的基本气象特征进行了分析.研究表明:冰川从4月中下旬开始即有明显消融,主消融期为5-9月,1月冰川区的气温最低.冰川中上部的气温直减率较小,说明该处的冰川冷效应较弱;而冰川下部较大的气温直减率,则可能主要与消融区连续的表碛覆盖有关.5-9月集中了全年约75%的降水,而冬季的降水稀少.降水的分布存在明显的高低分带,低降水带位于冰川中上部的海拔3 700 m附近,而冰川末端和冰川上部的降水量较大.受地形和下垫面条件的影响,冰川下部的山谷风非常发育,而冰川上部局地环流较弱.     

天山南坡科其卡尔巴契冰川度日因子变化特征研究

度日模型是估算冰川消融的一种简单而有效的方法.根据科其卡尔巴契冰川2003年的观测资料,分析了该冰川度日因子的空间变化规律及其影响因素.研究表明:各高度上的度日因子,介于2.0～9.7mm·℃^-1·d^-1之间变化,平均值为5.7mm·℃^-1·d^-1,与青藏高原各冰川及其它地区冰川相比较小;随着海拔的增高,度日因子随之递增;随平均气温的升高而随之递减.由于冰面状况复杂,度日因子变化幅度较大,裸冰区的度日因子明显大于表碛覆盖区.人为测量误差、反照率、地形等对度日因子的影响也不容忽视.     

天山南坡科其卡尔巴契冰川消融期气候特征分析

通过分析天山南坡科其卡尔巴契冰川区的气候变化特征及其对冰川消融变化过程的影响, 研究了冰川对气候变化的响应机理及其对塔里木河水资源的影响规律.科其卡尔巴契冰川区夏季气温比较高, 基本处于正温, 日较差较小; 气温直减率较小, 平均值为0.60·℃\5(100m)-1, 冰川冷效应不明显; 对流性降水较多, 降水量的75%发生在白天; 冰川区局地环流--山谷风发育, 海拔3 900 m以上冰川受西风环流影响显著; 净辐射在7月和8月中上旬均较大, 在8月下旬后净辐射开始逐渐减小, 与冰川消融是一致的. 7月初至7月下旬是消融较强的两个时段, 冰川平均消融速率为38.66 mm·5d-1, 到8月中旬消融速率略有降低, 平均为34.79 mm·d-1, 至9月中旬降至28.83 mm·d-1.     

冰川流域径流估算方法探索——以科其喀尔巴西冰川为例

利用科其喀尔巴西冰川2005年6月至2006年5月水文、气象资料,并结合15 m融合TM、1∶50000地形图、FY-2C数值产品和NCEP/NCAR再分析资料等,构建了10个简单、具有一定自主创新意义的分布式冰川融水径流模型(空间分辨率60 m),较好地模拟了研究冰川流域的日平均流量.结果表明,利用FY-2C总云量资料并结合辐射传输参数化方案能够较好地估算流域太阳入射短波辐射;单独利用总辐射有直接估算大型冰川流域某段时期融水径流的可能.气温与冰川末端流量呈指数关系,度日因子模型更适合于消融季节;提出的基于单元格气温和海拔的简单消融模型有望改进度日因子模型.在气温指数模型中加入太阳辐射调整系数,能够更好地估算冰川融水径流.简化分布式能量平衡模型能够反映大型冰川融水径流的变化;单层汇流方案在一定程度上能够概化托木尔型冰川的汇流过程.     

Interannual and seasonal variation of flow velocity in Koxkar Baxi Glacier from 2014 to 2020北大核心CSCD

Glacier flow is a key factor in understanding the nature of glaciers, and it is also one of the main research contents of glacier dynamics, which can provide basic support for rational utilization of glacier resources and early warning of glacier disasters. There are many mountain glaciers located in the west of China. The study on the spatiotemporal variation of surface velocity of glaciers also has great significance for the social and economic development of the western China. Koxkar Baxi Glacier, locates on the southern slopes of the Tomur Peak, is a typical dendritic glacier. In order to obtain the conditions of Koxkar Baxi Glacier’flow rates and its variation to further reveal the future of the variation of glacier, the spatiotemporal variability of glacier velocity was surveyed using correlation(COSI-Corr)method on Landsat imagery from 2014 to 2020. The results show that: (1)The average annual flow velocity of the Koxkar Baxi Glacier was 0. 04~0. 05 m·d-1 during 2014 to 2020. (2)The glacier reaches its maximum flow velocity near the center part, and the velocity decreased towards both lateral margins. In a longitudinal profile, ice flow velocity in the accumulation area increased down to the equilibrium line, while decreased towards the glacier terminal. The maximum velocity with 0. 17~ 0. 20 m·d-1 was found near the equilibrium line altitude. (3)The glacier flow velocity in warm seasons were 16. 67% faster than that in cold seasons. (4)The glacier flow velocity from 2014 to 2020 showed a slight decreasing trend, and the average flow velocity decreased 0. 01 m·d-1. (5)Temperature and precipitation had certain influence on the seasonal fluctuation and interannual variation of the flow velocity of the glacier. © 2022 Science Press (China). All rights reserved.     

Study on the change of Keqikaer Glacier during the last 30 years,Mt. Tuomuer,Western China

Using radio echo sounder, ice thickness of Keqikaer Glacier tongue was measured in 1981 and 2004. Data obtained by comparing topographical maps, aerial and satellite photographs at different times, illustrates changes of the thickness and advance/retreat of Keqikaer Glacier. Keqikaer Glacier has been in intensive retreat since the 1990s and become thinner since the 1980s. Measured thickness of the ice tongue indicates reducing with a speed of 0.5–1.5 m a⁻¹ since 1981. The shrinkage of the glacier terminus is less than 2% of the total length during the last 30 years; however, the retreat of terminus position and the thinning of the ice thickness provides significant information that these glaciers on the south slope of Mt. Tuomuer are in an intensively decreasing phase in recent time.     

The application of artificial neural networks to simulate meltwater runoff of Keqikaer Glacier,south slope of Mt. Tuomuer,western China

Because glacial melting provides a significant amount of surface water resources, especially in cold arid regions, it is critical that effective methods be developed for predicting their behavior. Glacier runoff differs from other types of stream flows, being characterized by large diurnal fluctuations, with maximum discharge during the summer months. Moreover, the size and remoteness of glaciers makes them difficult to study directly. Hence, developing effective modeling techniques is our best hope for understanding and predicting glacial melting phenomena. In the past, physics-based models have been used with some success. In this study, conducted in 2003 and 2004 on the Keqikaer Glacier on the south slope of Mt. Tuomuer, however, we used the newer artificial neural networks (ANNs) modeling technique. As the input nerve cell, we used the hourly wind speed, precipitation, air temperature, radiation balance, and ground temperature; the output nerve cell was the diurnal runoff at the glacial terminus. We then analyzed the simulated results under different scenarios by varying the input-nerve-cell parameters. It was found that ANN can simulate the process of glacier meltwater runoff successfully when basic parameters such as air temperature, precipitation and radiation balance are few. The results indicate that ANN can simulate the process of glacial meltwater runoff quite well, and that meteorological variables could in fact be used successfully to simulate glacier meltwater runoff using the ANN method.     

全球变暖背景下海螺沟冰川近百年的变化

海螺沟冰川是我国典型的温冰川之一,对100 a来各种观测资料的分析发现:海螺沟冰川自1823年以来末端海拔上升300 m,年均升高1.64 m,20世纪以来末端海拔上升速度加快;在20世纪呈现明显的退缩变化,76 a冰川后退1 821.8 m,年均后退24 m.运用冰川学方法恢复了海螺沟冰川45a来的物质平衡变化,45 a累积物质平衡值为-10 825.5 mm(水当量),年均平衡值为-240.6 mm(水当量).在全球变暖影响下,冰川雪线不断上升,冰川活动强烈,导致冰面形态发生了明显变化,具体表现为:冰川厚度不断变薄、大冰瀑布上出现巨大塌陷洞穴、冰面丘融化变形、冰面径流不断变大、冰川弧拱区裂隙密布等,冰川内部的径流冲刷和冰川表面的剧烈消融是海螺沟冰川表面形态发生显著变化的主要机制.总之,在全球变暖背景下,该冰川表现出以亏损为特征的退缩变化趋势.     

七一冰川消融末期融水化学日变化特征

2006年9月1-8日在祁连山七一冰川作用区水文总控点逐时采集河水样, 并分析水样的主要可溶离子含量、电导率以及pH, 研究冰川作用区水化学组成日变化特征. 结果表明: 消融末期河水中pH的平均值约为7.60, 与离子浓度时间变化过程一致, 说明是偏碱性物质的输入增加了融水中化学物质的含量;SO~(2-)_4, Ca~(2+)分别是浓度最大的阴、阳离子, 属于SO~(2-)_4+HCO~-_3-Ca~(2+)+Mg~(2+)型水. 河水中可溶性离子浓度日变化过程具有不对称性, 表现为快速降低和缓慢的增加过程, 与流量变化呈显著反相关, Pearson相关说明流量是冰川区水化学特征随时间变化的控制性因素;阳离子通量计算显示, 在七一冰川区达54.7 t·km~(-2)·a~(-1), 其日变化过程与流量正相关, 与离子浓度成反相关, 说明径流量也是控制离子通量的主要因素.     

希夏邦马峰抗物热冰川离子淋溶作用对冰芯记录的影响(英)

The ion elution process has a severe effects on the formation of ice core record, which is discussed on the results of ice core record from kangwure Glacier, Xixabangma Peak.     

中国-巴基斯坦喀喇昆仑公路Ghulkin冰川百年进退变化

巴基斯坦喀喇昆仑山的Ghulkin冰川是距离中国-巴基斯坦喀喇昆仑公路最近的典型冰川之一,其冰川的进退变化影响着喀喇昆仑公路改建工程的线路设计与工程施工.为了追溯Ghulkin冰川的活动历史和查明近期进退变化,对过去200 a的相关文献和记录进行统计分析,并开展了2008-2011年野外定点观测,总结与分析了Ghulkin冰川冰舌的活动历史与近期变化.研究表明：Ghulkin冰川在1885-1980年近百年间经历了3次前进和3次后退,在此期间冰川波动了625 m;1913-1925年冰川处于显著的前进状态,1966-1978年冰川有小段距离的前进;2008-2011年K676+660处泥石流沟道逐年抬升,2011年南坡冰川融水由K676+660改道至K676+450;2010年的南坡冰舌较1994年后退了300余米,2011年的南坡冰舌较2010年后退了15.066 m,可见在2010-2011年期间冰川处于局部短期后退状态. 中巴公路冰川泥石流等灾害不但受区域气候的影响,而且还受冰川变化的影响.未来气候变暖将会导致冰川的强烈消融和后退,冰川融水携带大量冰碛体,形成大型的冰川泥石流,对公路的安全运营造成严重威胁.     

Factors Affecting the Variation of Glacier Surface Runoff-Coefficient in the Recent Years

The mass balance of Urumqi Glacier No.1 (Glacier No.1) was calculated by water balance method and direct measurement method respectively. Water balance method is a kind of calculating method, which studies about the relationship between storage, supply and consumption of water resource in a certain area in a certain period of time (Time for this research is a mass balance year).Mass balance calculated by this method and acquired by filed observation was compared and analyzed. Therefore we got their correlation and expected to apply it to other high latitude and altitude areas.Mass balance and glacial runoff data of Urumqi Glacier No.1 used in this research were acquired from Annual Report of Tianshan Glacier Station, and that started observing in 1959.The data used by this study is collected from 1982-2014. The data of runoff was measured by the hydrology station of Urumqi Glacier No.1 Glacier, which is located in the lower reaches of the glacier about 300 m, and catchment area is about 3.34 km².The data of precipitation and runoff was provided by Daxigou Meteorological Station located in the altitude of 3 539 m, which is distant from the terminus of Urumqi No.1 Glacier about 3 km.Through the comparison of these two kinds of methods, we found that: ①It is better to use water balance method to calculate the mass balance in long time series. The result of water balance method was 1% different from the result of direct measurement during 1982-2014, and the corresponding glacier runoff coefficients were 0.7 and 0.85, respectively. ②The results of water balance method during 1982-2005 had a high correlation with the direct measurements, and the error was relatively small. Besides that, the glacier runoff coefficient reflected the glacier runoff well. However, there were obvious differences between the two kinds of methods during 2005 2012 which showed that the glacier runoff coefficients changed a lot. According to analyzing the two periods of 2005 to 2008 with large error and 1996 to 1999 with small error, we found that the results of water balance method were generally higher than that of the direct measurement in summer. The analysis showed that the changes of water conditions and the corresponding in the glacier runoff coefficient were the main reasons for these differences.The data of precipitation and runoff in the study area was combined with the measured mass balance data, and their potentially internal relationship was found, which could be used to acquire the meteorological data easily and to deduce the mass balance data which is difficult to be acquired. This conclusion is helpful to extending the study area from a single glacier or basin to a large regional scale. Limited to the shortage of data, for the example, this study only discusses the single glacier, Urumqi Glacier No.1. Overall, this study shows that using the potential of water balance method can compute the data of glacier mass balance more accurate on long time scale.     

The Features of Climate Variation and Glacier Response in Mt.Yulong,Southeastern Tibetan Plateau

The Features of climate change in Mt.Yulong, southeasten Tibetan Plateau were analyzed using linear regression, Mann Kendall abrupt test and Morlet wavelet analyses. In addition, the relationship between glacier retreating (Baishui Glacier No.1) and climate warming wasalso analyzed in this study. The main results are showedas follow: ① The annual mean temperature, precipitation have an increasing trend, withinclination rates being 0.15℃/10a and 9.0 mm/10a;annual temperaturedramatically ascend in 1998 with the change values 0.7 ℃; Morlet waveletsin annual temperature andtemperature in dry season mainly have a 10 to 15 year periods,while annual precipitation amount and the precipitation in rainy season presented a quasi 10 year periods. ②Prior to 1998, the important meteorological factor influencing the change of Baishui Glacier No.1 are temperature and precipitation, while in the following years, temperature plays a more important role in affecting its retreat and advance; The main characteristic ofvertical climate change in Mt. Yulong (1982/2009) is that the cold season shortens and temperature rises with elevation, and the maximal value of increased temperature in glacier zone is 2.2~2.5 ℃, resulting in greatly accelerated glacier ablation.     

近15a喜玛拉雅山中段波曲流域冰川和冰湖变化

西藏聂拉木县波曲流域内分布有大量的冰川和冰湖,通过对2000/2001年度遥感数据解译并与1987年的数据对比,发现近15 a来该流域内的冰川面积、冰湖数量和面积等均发生了巨大的变化,结果表明:冰川总面积减小了20%,>0.020 km²的冰湖数量增加了11%,冰湖面积增加了47%.其中位于西夏邦马峰东侧的嘎龙错和扛西错最为典型,面积分别增加了104%和118%.2005年夏季野外考察对以上资料进行了核实.在全球气候变暖的趋势下,预计该流域内的冰川面积将进一步缩小,冰湖数量在小幅增加后将会出现大规模的冰湖溃决,导致严重的泥石流灾害.     

天山庙尔沟平顶冰川的基本特征和过去24a间的厚度变化

山岳冰川在20世纪出现的全面退缩以及在最近20 a的加速消融是近年来国际冰川与全球变化研究的热点问题之一.庙尔沟平顶冰川位于天山山脉的最东段,南、北、东外围为气候十分干燥的荒漠戈壁,高山冰川是哈密绿洲主要的水资源,其冰芯记录包含有起源于这一地区的沙尘暴信息.因此,对该冰川的研究一直为人们所关注.基于2004年和2005年对庙尔沟平顶冰川的考察和取得的冰芯资料,初步探讨了庙尔沟平顶冰川的基本特征和过去24 a间的厚度变化.