丹麦哥本哈根丹麦和格陵兰地质调查局Nanna B. Karlsson团队在格陵兰峡湾检测到冬季冰下融水。2025年3月11日出版的《自然—地球科学》杂志发表了这项成果。

冰川前缘和海水之间的相互作用是预测未来冰块损失的关键不确定性之一。冰川前缘的直接观测很少，但研究表明，淡水通量的大小和时间对于决定峡湾环流、冰锋融化和生态系统宜居性至关重要。特别是，由于无法进入的条件，冬季动力学的研究严重不足，导致对夏季观测的偏倚。

研究组介绍了格陵兰岛冬末在海洋终止冰川前方和周围峡湾获得的温度和盐度的现场观测结果。该观察表明，冰川前缘存在一个异常新鲜的水池，这表明冰川床上产生的融水是在冬季排放的。结果表明，温暖的大西洋水和营养物质被夹带在冰川前缘，导致冰川前缘融化加剧，营养水平提高。该发现对理解冰川前缘和海水之间的热交换、冰川前缘融化率、海洋混合和洋流以及生物生产力具有重要意义。

附：英文原文

Title: Winter subglacial meltwater detected in a Greenland fjord

Author: Hansen, Karina, Karlsson, Nanna B., How, Penelope, Poulsen, Ebbe, Mortensen, John, Rysgaard, Sren

Issue&Volume: 2025-03-11

Abstract: The interaction between glacier fronts and ocean waters is one of the key uncertainties for projecting future ice mass loss. Direct observations at glacier fronts are sparse, but studies indicate that the magnitude and timing of freshwater fluxes are crucial in determining fjord circulation, ice frontal melt and ecosystem habitability. In particular, wintertime dynamics are severely understudied due to inaccessible conditions, leading to a bias towards summer observations. Here we present in situ observations of temperature and salinity acquired in late winter in Greenland at the front of a marine-terminating glacier and in surrounding fjords. Our observations indicate the existence of an anomalously fresh pool of water by the glacier front, suggesting that meltwater generated at the bed of the glacier discharges during winter. The results suggest that warm Atlantic water and nutrients are entrained at the glacier front, leading to enhanced frontal melt and increased nutrient levels. Our findings have implications for understanding the heat exchange between glacier fronts and ocean waters, glacier frontal melt rates, ocean mixing and currents, and biological productivity.

DOI: 10.1038/s41561-025-01652-0

Source: https://www.nature.com/articles/s41561-025-01652-0