阿拉斯加快速增长的边缘冰湖是由冰川通过床的退缩驱动的过度深化
Daniel McGrath1, Louis Sass2, William H Armstrong3
1Department of Geosciences, Colorado State University, Fort Collins, CO 80523.
概括
阿拉斯加的冰川湖扩张正在加速,最近80%的增长发生在冰川下盆地. 这些盆地表明,随着冰川的退缩,湖泊的增长可能会增加四倍,并且会出现新的湖泊.
科学领域:
- 冰川学的冰川学
- 地质形态学 地质形态学
- 气候变化科学 气候变化科学
背景情况:
- 全球范围内的边缘冰湖正在扩大,特别是在冰川床的过度深化中.
- 量化冰川湖的膨胀速度,驱动因素和未来的延伸是非常重要的,因为它们的危险和对冰川动态的影响.
- 冰川湖可以加速冰川的流动和撤退,改变水文和生态系统.
研究的目的:
- 为了量化最近在阿拉斯加的冰边湖的增长.
- 将冰川床的过度深化绘制为目前和未来湖泊发展的预测因素.
- 评估未来冰川湖扩张的潜力及其对冰川演变的影响.
主要方法:
- 利用现有的冰厚和地形数据来绘制阿拉斯加冰川床的过度深化.
- 量化冰边缘湖面积在2018年至2024年间的变化,与以前的速度 (2009年至2018年) 相比.
- 分析了带有和没有冰边湖的冰川的冰川速度和稀释率.
主要成果:
- 阿拉斯加的边缘冰湖在2018-2024年间增长了156平方公里 (26平方公里/年),比前十年的增长率增加了50%.
- 近期湖泊增长的80%发生在已绘制的冰川床过度深化区域内.
- 超过4,250平方公里的过度深化区域与现有湖泊相连,这表明增长的潜力超过4倍,另外有14500平方公里可用于新湖泊形成.
- 冰边湖泊的冰川比没有湖泊的类似冰川显现出23-54%的更大稀释.
结论:
- 冰川床的过度深化是阿拉斯加冰川湖扩张的关键预测因素.
- 阿拉斯加的冰川面临着未来湖泊增长的巨大潜力,影响冰川撤退的动态.
- 冰川和冰边湖之间的动态合显著影响了冰川的稀释和演变.
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