权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Assessment of effects on sea-level changes due to recessions of large-scale temperate glaciers caused by global warming

全球变暖导致大面积温带冰川消退对海平面变化的影响评估

基本信息

批准号：
11640422
负责人：
NARUSE Renji
金额：
$ 2.05万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11640422/
关键词：
Patagonia Glacier Snow and ice core core drilling Calving Flow Accumulation rate Glacier variation 地球温暖化温暖氷河海水面変動応答時間気候変化氷山分離消耗量

项目摘要

This study was conducted by analyzing mostly the samples and data obtained from the field surveys at glaciers in Patagonia, South America, made in 1999 and 2000. Ice-core drilling was carried out in December 1999 near the head(1756m a.s.l.)of the accumulation area of Tyndall Glacier. Analyses of stable oxygen and hydrogen isotopes as well as major ions and biomass along a 46-m-long ice-core were made in laboratories to estimate accumulation rates over the Patagonia Icefield. Annual net accumulation rate was estimated as 17.8m a^<-1> w.e.in the balance year of 1997/98-1998/99, whereas 11.0m a^<-1> in 1998/99-1999/00. This high net-accumulation rate ranks Tyndall Glacier as one of the more extreme maritime glaciers in the world. Almost all large-scale glaciers in Patagonia calve into fjords to the west and into lakes to the east. Dynamic behavior of the lacustrine calving Upsala Glacier was studied, and it was found that the frontal variations should be affected by the bed topography and longitudinal stretching of the glacier. A linear relationship between calving velocity and water depth near the calving terminus was derived from freshwater calving glaciers in Patagonia. Measurements of flow velocities and calving events were carried out in December 1999 near the terminus of Glaciar Perito Moreno. The largest velocity was obtained as 2.7m d^<-1> at the front tip. A dynamic glacier model was constructed on the basis of measurements of flow velocity and ablation rates at Soler Glacier and others.

本研究主要是通过分析1999年和2000年在南美巴塔哥尼亚冰川进行的实地调查所获得的样品和数据进行的。1999年12月，在靠近头部（海拔1756米）的地方进行了冰芯钻探。位于廷德尔冰川的堆积区。在实验室中对稳定的氧和氢同位素以及沿沿着46米长冰芯的主要离子和生物量进行了分析，以估计巴塔哥尼亚冰原的积累率。在<-1>w.e.in1997/98-1998/99的其余年份，年净积累率估计为1780万美元，而<-1>在1998/99-1999/00年，年净积累率为1100万美元。这种高的净积累率使廷德尔冰川成为世界上最极端的海洋冰川之一。巴塔哥尼亚几乎所有的大规模冰川都向西裂入峡湾，向东裂入湖泊。通过对乌普萨拉湖相崩解冰川动力学行为的研究，发现冰川锋面变化受河床地形和冰川纵向伸展的影响。在巴塔哥尼亚的淡水崩解冰川中，崩解速度和崩解终点附近的水深之间存在线性关系。1999年12月，在冰川佩里托莫雷诺的终点附近进行了流速和产冰事件的测量。最大速度在前端获得为2.7m d^<-1>。根据对索勒冰川和其他冰川的流速和消融率的测量，建立了一个动态冰川模型。