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1.
Tree-ring-based mass-balance estimates for the past 300 years at Peyto Glacier, Alberta, Canada 总被引：1，自引：0，他引：1
Tree rings were used to reconstruct mass balance for Peyto Glacier in the Canadian Rocky Mountains from A.D. 1673 to 1994. Summer balance was reconstructed from tree-ring estimates of summer temperature and precipitation in the Canadian Rockies. Winter balance was derived from tree-ring data from sites bordering the Gulf of Alaska and in western British Columbia. The models for winter and summer balance each explain over 40% of the variance in the appropriate mass-balance series. Over the period 1966-1994 the correlation between the reconstructed and measured net balances is 0.71. Strong positive mass balances are reconstructed for 1695-1720 and 1810-1825, when higher winter precipitation coincided with reduced ablation. Periods of reconstructed positive mass balance precede construction of terminal moraines throughout the Canadian Rockies ca. 1700-1725 and 1825-1850. Positive mass balances in the period 1845-1880 also correspond to intervals of glacier readvance. Mass balances were generally negative between 1760 and 1805. From 1673 to 1883 the mean annual net balance was +70 mm water equivalent per year (w.e./yr.), but it averaged −317 mm w.e./yr from 1884 to 1994. This reconstructed mass balance history provides a continuous record of glacier change that appears regionally representative and consistent with moraine and other proxy climate records. 相似文献
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Gregory C. Wiles Daniel E. Lawson Eva Lyon Nicholas Wiesenberg R.D. D'Arrigo 《Quaternary Research》2011,76(2):190-195
Two interstadial tree ring-width chronologies from Geikie Inlet, Glacier Bay Southeast, Alaska were built from 40 logs. One of these chronologies has been calendar dated to AD 224–999 (775 yr) crossdating with a living ring-width chronology from Prince William Sound, Alaska. Trees in this chronology were likely killed through inundation by sediments and meltwater from the advancing Geikie Glacier and its tributaries ca. AD 850. The earlier tree-ring chronology spans 545 yr and is a floating ring-width series tied to radiocarbon ages of about 3000 cal yr BP. This tree-ring work indicates two intervals of glacial expansion by the Geikie Glacier system toward the main trunk glacier in Glacier Bay between 3400 and 3000 cal yr BP and again about AD 850. The timing of both expansions is consistent with patterns of ice advance at tidewater glaciers in other parts of Alaska and British Columbia about the same time, and with a relative sea-level history from just outside Glacier Bay in Icy Strait. This emerging tree-ring dated history builds on previous radiocarbon-based glacial histories and is the first study to use tree-ring dating to assign calendar dates to glacial activity for Glacier Bay. 相似文献
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Boreal temperature variability inferred from maximum latewood density and tree-ring width data, Wrangell Mountain region, Alaska 总被引：3，自引：0，他引：3
Variations in both width and density of annual rings from a network of tree chronologies were used to develop high-resolution proxies to extend the climate record in the Wrangell Mountain region of Alaska. We developed a warm-season (July–September) temperature reconstruction that spans A.D. 1593–1992 based on the first eigenvector from principal component analysis of six maximum latewood density (MXD) chronologies. The climate/tree-growth model accounts for 51% of the temperature variance from 1958 to 1992 and shows cold in the late 1600s–early 1700s followed by a warmer period, cooling in the late 1700s–early 1800s, and warming in the 20th century. The 20th century is the warmest of the past four centuries. Several severely cold warm-seasons coincide with major volcanic eruptions. The first eigenvector from a ring-width (RW) network, based on nine chronologies from the Wrangell Mountain region (A.D. 1550–1970), is correlated positively with both reconstructed and recorded Northern Hemisphere temperatures. RW shows a temporal history similar to that of MXD by increased growth (warmer) and decreased growth (cooler) intervals and trends. After around 1970 the RW series show a decrease in growth, while station data show continued warming, which may be related to increasing moisture stress or other factors. Both the temperature history based on MXD and the growth trends from the RW series are consistent with well-dated glacier fluctuations in the Wrangell Mountains and some of the temperature variations also correspond to variations in solar activity. 相似文献
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天山南坡科契卡尔巴西冰川物质平衡初步研究 总被引：14，自引：7，他引：7
基于2003—2005年考察期间观测的气温与降水资料,运用度日物质平衡模型模拟了天山南坡科契卡尔巴西冰川近期的物质平衡变化状况.结果表明:度日物质平衡模型模拟的冰川物质平衡值与实测值的变化趋势基本一致,模型模拟结果较为理想;2003/2004年度和2004/2005年度两个物质平衡年的平均物质平衡值分别为-494和-384 mm,平衡线高度(ELA)比20世纪70年升高了300 m左右.由此可见,在由暖干向暖湿转型的气候背景下,尽管降水增加显著,但强烈的升温导致科契卡尔巴西冰川处于强烈的物质亏损状态. 相似文献
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Exploring the potential of tree-ring chronologies from the Trafoi Valley (Central Italian Alps) to reconstruct glacier mass balance 总被引：2，自引：0，他引：2
GIOVANNI LEONELLI MANUELA PELFINI PAOLO CHERUBINI 《Boreas: An International Journal of Quaternary Research》2008,37(1):169-178
Two tree-ring chronologies of stone pine ( Pinus cembra L.) and two of Norway spruce ( Picea abies Karst.) were constructed on the basis of data from three high-altitude sites in the Trafoi Valley (Central Alps, Italy) to test tree species sensitivity to climate at different sites and to explore the potential of the two species for reconstructing the mass balance of two glaciers in the same region (the Careser and Hintereis glaciers). Influence of climate on tree-ring growth and on glacier mass variations was tested by means of Pearson's correlation and response functions. At highest altitude sites, both species appeared to be sensitive to July temperatures, while stone pine also showed higher sensitivity than Norway spruce to previous winter precipitation. Comparing the dendrochronological and glaciological series, stone pine showed higher negative correlations with glacier mass balance series than Norway spruce. These different relationships reflect different species responses to climate, and stone pine is potentially useful in reconstructing past glacier mass balance in the Central Alps. Extreme climatic events induce different and even contrasting responses of tree-ring growth and glacier mass variations and may therefore bias tree-ring-based glacier mass balance reconstructions. 相似文献
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Studying the mass balance on the Xiao Dongkemadi Glacier and Hailuogou Glacier shows that the mass balance variation of continent type glacier in the interior of the plateau is in the same phase with that of the marine type glacier in the southeast margin of the plateau. However, the mass balance in the continent type glacier is always positive, and the marine type glacier is in large negative mass balance. The continent type glacier is slow to climate change and the marine glacier is sensitive to climate change. 相似文献
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天山乌鲁木齐河源1号冰川物质平衡特征 总被引：7，自引：2，他引：5
统计了天山乌鲁木齐河源1号冰川自1980年以来冰川表面的单点物质平衡,分析了不同季节物质平衡及其冰川变化特征。研究表明,1号冰川厚度较之1959年平均减薄了9 599 mm;1997—2002年为实际观测以来连续的强负物质平衡时段,平均物质平衡为-739.6 mm /a。物质平衡与气温、降水的相关分析显示：1号冰川物质平衡主要取决于夏季平均气温的高低,二者具有较好的反相关关系（相关系数为-0.72）,而与降水的关系相对较差。20世纪80年代末以来,1号冰川退缩速度明显增大,尤以2000—2002年为甚,西支冰川退缩速度为连续的高值(退缩速度分别为6.92 m/a、6.95 m/a和6.25 m/a);东支冰川的退缩速度与高度大于4 200 m的高度带区间的平均物质平衡值有较好的相关关系（相关系数为0.65）,表明了1号冰川进退的动力主要源于冰川积累区的物质平衡大小。 相似文献
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物质平衡是冰川与气候相互作用的关键桥梁, 对气候变化非常敏感。基于青冰滩72号冰川2008 - 2014年冰面花杆和雪坑的观测资料, 结合Landsat系列卫星影像, 利用零平衡线法对青冰滩72号冰川的物质平衡进行计算和分析。结果表明： 青冰滩72号冰川2008 - 2014年平均物质平衡梯度为（0.86 ± 0.19） m w.e.?（100m）-1; 平衡线高度在（4 109 ± 23） ~ （4 317 ± 92） m a.s.l.之间变化, 平均为（4 167.5 ± 33.2） m a.s.l。同时, 青冰滩72号冰川年净物质平衡介于-1.23 m w.e. ~ +0.31 m w.e., 年平均为-0.38 m w.e., 累积物质平衡为-2.27 m w.e.。此外, 与位于天山地区图尤克苏冰川、 乌鲁木齐河源1号冰川平衡线高度和累积物质平衡的比较发现, 青冰滩72号冰川平衡线高度和物质平衡的变化与图尤克苏冰川相似, 而与乌鲁木齐河源1号冰川的差异相对较大。 相似文献
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冰川物质平衡研究对流域内水资源的分配和利用具有重要的指导意义。发源于祁连山的冰川融水是河西走廊和柴达木盆地重要的淡水来源。近年来,祁连山地区的冰川经历了不同程度的退缩,东段退缩尤其明显。基于祁连山东段冷龙岭地区宁缠河1号（NC01）冰川2010—2020年冰川物质平衡观测数据,结合Google Earth高分辨率历史影像、资源3号和哨兵2号卫星影像,以及气象数据,采用冰川学方法,分析了NC01冰川的面积、物质平衡及厚度变化等特征。结果表明：2008—2020年,NC01冰川末端位置持续后退,退缩速率为7.54 m·a-1;2020年冰川面积为3.32×105 m2,萎缩速率为0.075×105 m2·a-1。与此对应,2010—2020年冰川物质平衡持续为负,年均物质平衡为-0.98 m w.e.。由此推算,2020年冰川平均厚度减薄至17.52 m,冰量减少至6.83×106 m3。进一步研究显示,自1972年以来,NC01冰川持续减薄,而2010—2020年物质亏损速率要高于1972—2010年,存在着较为明显的后期加速趋势,这与近年来气温的明显升高有关。 相似文献
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祁连山老虎沟12号冰川表面能量和物质平衡模拟 总被引：6，自引：4，他引：2
采用HOCK的分布式能量物质平衡模型对老虎沟12号冰川消融期的物质平衡进行了模拟,时间步长为1 h,空间分辨率为30 m. 模型结果利用物质平衡观测数据和气象站观测数据验证,模型模拟时期为2012年6月1日-9月30日. 模型模拟结果表明,地形因子对太阳辐射影响相当显著;散射辐射在总辐射中的比例较大为39%,模拟期冰川表面物质平衡为-506 mm w.e.. 在模拟期整个冰川平均上净辐射占能量收入的84%,感热通量占有16%;消融耗热则是能量的主要支出占有62%,潜热通量占有能量支出的38%. 相似文献
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冰川物质平衡模式及其对比研究——以祁连山黑河流域十一冰川研究为例 总被引：6，自引：4，他引：2
冰川物质平衡是冰川连结气候和水资源的纽带, 对其的观测和模拟始终是冰川与气候变化研究领域的重点和前缘之一. 以祁连山黑河流域十一冰川为参照冰川, 结合实测物质平衡验证资料, 建立了基于冰川表面能量平衡的冰川物质平衡模型(物理模型)和基于温度参数、温度-辐射参数和温度-辐射-水汽压参数的三种度日因子模型(统计模型), 并对模拟结果进行了分析及评估. 结果表明: 净辐射是冰川表面最主要的能量来源, 占能量收入的82.3%; 其次为感热供热, 占收入的17.7%. 净长波辐射基本为负, 吸收的热量主要通过融化和蒸发/升华方式消耗, 分别占能量支出的84.7%和15.3%. 加入净短波辐射和水汽压参数的度日因子-物质平衡模型的模拟效果提高显著, 相对误差为7%, 与能量平衡模型的模拟误差6.7%, 相差不大. 研究表明, 能量-物质平衡模型的物理意义明确, 模拟能力强大, 尤其在日尺度上有绝对的优势; 统计物质平衡模型在特定的地理条件和气候条件下表现出不佳, 对于一些极端值的模拟能力欠缺, 但是具有输入变量少, 计算简单的优点. 研究结果对黑河流域乃至整个祁连山地区的冰川物质平衡模拟方法的建立具有参考意义. 相似文献
12.
ROBERT WILSON DAVID FRANK JOHN TOPHAM KURT NICOLUSSI JAN ESPER 《Boreas: An International Journal of Quaternary Research》2005,34(4):490-497
Most palaeoclimate studies in Central Europe, utilizing annually resolved proxies such as tree-ring and documentary sources to reconstruct past temperatures, have focused mainly upon single sites or regional studies. The combined information of published summer temperature reconstructions from the Alpine region show a generally coherent picture of cool conditions for the periods c. 1450-1475, 1575-1610, 1660-1710, 1800-1850 and 1875-1925. These reconstructed cool periods can be partly explained by external forcing (e.g. low solar activity and volcanic events). However, these reconstructions, in their present form, cannot be used to comparatively assess spatial summer temperature variability through the region due to methodological differences in their development and the fact that many of them were not originally developed to emphasize spatial patterns. We propose that a network of tree-ring chronologies which have been processed in a consistent way would allow the robust reconstruction of spatial summer temperature variability for high elevations in Central Europe. Unfortunately, most living tree-ring chronologies only go back into the 18th century - so restricting the length of reconstruction. As a possible solution, we introduce a historical database of ring-width series, measured from string instruments, that could be used to extend high elevation spruce chronologies in Central Europe back for at least 500 years. 相似文献
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In this study, we aim to examine past dry and wet events for the western Anatolia, performing local and spatial reconstructions. 17 new black pine site chronologies were developed, May–June precipitation time series were reconstructed for four localities, and the first spatial May–June precipitation reconstruction was achieved for western Anatolia. The long-term local May–June precipitation reconstructions contain mostly one-year and, less commonly, two-year drought events. The longest consecutive dry period (AD 1925–1928) in the reconstructed time series for Kütahya lasted four years. Spatial reconstructions revealed that between AD 1786 and 1930 the extreme dry years for all of western Anatolia were AD 1887, 1893, 1794 and 1740. The driest year during the 215-year-long period under consideration was 1887. The wettest years for the entire western Anatolia were determined to be AD 1835, 1876, 1881 and 1901. There is a big overlap between agricultural famine years and dry years as determined from reconstructions. In this context, our study provides a basis for understanding agricultural drought and better management of regional water resources. 相似文献
16.
入湖冰川受冰湖作用影响,物质损失速率高于其他类型冰川,并导致冰湖进一步扩张,冰湖溃决风险增加。建立入湖冰川物质变化序列,对揭示不同类型冰川对气候变化的响应特征,以及评估冰湖溃决风险研究具有重要意义。基于中国地面气象要素驱动数据集和实测气象数据,采用冰川表面能量-物质平衡模型估算了冰川表面物质变化,并结合冰川流动和末端退缩特征,重建了1989-2018年龙巴萨巴冰川物质变化序列。结果表明,近30a龙巴萨巴冰川总物质损失为0.315km^(3)w.e.,平均物质变化速率为-0.114km^(3)w.e.·a^(-1)。冰川平均表面物质平衡为-0.26m w.e.·a^(-1),表面消融是冰川物质亏损的主要贡献因素。气温变化对冰川表面物质损失的影响高于降水;冰川表面物质平衡对夏季气温和降水变化的敏感性强于其他季节;表碛覆盖加速了冰川表面消融,且较薄的表碛厚度会加剧冰川表面物质损失。 相似文献
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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. 相似文献
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北半球冰川物质平衡的突变 总被引：1，自引：1，他引：0
据世界冰川监测处（ＷＧＭＳ）收集,编辑和出版的全球冰川物质平衡序列资料,用序列平均滑动ｔ检验,探测了北半球２０ａ以上长序列３３条冰川的１０ａ尺度突变。结果表明,突变发生年代的区域特征与气候环流背景突变很相近。证实冰川年物质平衡序列反映气候背景突出的能力与灵敏性。 相似文献
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近期小冬克玛底冰川物质平衡变化及其影响因素分析 总被引：8，自引：6，他引：2
冰川物质平衡是反映冰川状况最为直接、 可靠的参数.基于2008-2012年小冬克玛底冰川花杆和雪坑实测的物质平衡资料以及相关的气象资料, 获取了小冬克玛底冰川物质平衡数据并对其影响因素进行了分析.结果表明: 2009-2012年冰川末端共退缩19.7 m, 年均退缩量为4.9 m, 是1990年代中末期的2.3倍; 平衡线高度为5 720 m, 相比1990年代初的海拔5 600 m上升了120 m.与1995年相比, 冰川面积减少了0.095 km2, 末端海拔从5 380 m上升到5 420 m. 2008-2012年小冬克玛底冰川物质平衡总量为-1 584 mm w.e., 相当于冰川整体减薄1.76 m. 2009/2010年度物质平衡量为-996 mm w.e., 是小冬克玛底冰川有观测记录以来的最大负平衡值, 夏季平均气温偏高和青藏公路维修导致表面反照率急剧降低是主要原因.对影响冰川物质平衡的因素分析结果表明, 气温特别是夏季气温和净辐射是小冬克玛底冰川物质变化的主要影响因素. 相似文献