Szafraniec Joanna Ewa
Faculty of Natural Sciences, Institute of Earth Sciences, University of Silesia in Katowice, Sosnowiec, 41-200, Poland.
Sci Rep. 2025 Jul 2;15(1):22622. doi: 10.1038/s41598-025-07346-2.
Like other higher latitudes, Iceland is experiencing climate warming, leading to glacier retreat and the formation of new plume areas of aeolian material - vast deserts, including the Skeiðarársandur outwash plain. The main objective was determining the annual rate of aeolian accumulation within glacial flood-origin sandur kettle holes as important sediment traps. The analysis was based on data collected in 2021/2022-2023/2024, at an older level, in depressions after 1892 and 1934/1938 glacial lake-outburst floods, and at a younger level, after the catastrophic jökulhlaup of 1996. Meteorological data, digital elevation models, satellite scenes and photogrammetric data were also used to examine the role of wind, morphometry of kettle holes, and plant coverage in the aeolian accumulation rate and to validate the monitoring results. Analysis showed that the material collected in the kettle holes was of local origin. On the younger level, without vegetation or an initial succession, particle transport occured mostly via saltation (63-75%), and the aeolian aacumulation rate averaged 5,000-7,400 g m yr (50% between 3,600 and 13,400 g m yr). It is several times higher than on the flat sandur surface and 6-44 times higher than on the older level, completely covered with vegetation, and more distant from plume areas. Mineral particles here were finer and transported mainly in suspension (50-85%). Identifying aeolian facies and particle characteristics within the analogous Pleistocene sandur kettle holes of the glacial lake-outburst flood-origin in the European Lowland may indicate the time of their formation caused by climate warming, the Scandinavian Ice Sheet decay, and the transformation of ecosystems from tundra to forest.
与其他高纬度地区一样,冰岛正在经历气候变暖,导致冰川消退,并形成了新的风沙物质羽流区——广阔的沙漠,包括斯卡夫塔费德冰河湖外冲平原。主要目标是确定冰川洪水形成的冰河湖外冲平原锅穴(作为重要的沉积物陷阱)内风沙堆积的年速率。分析基于2021/2022 - 2023/2024年收集的数据,在较老的层面上,是1892年和1934/1938年冰川湖溃决洪水后洼地的数据,在较年轻的层面上,是1996年灾难性冰川溃决洪水后的数据。气象数据、数字高程模型、卫星图像和摄影测量数据也被用于研究风的作用、锅穴的形态测量以及植被覆盖对风沙堆积速率的影响,并验证监测结果。分析表明,在锅穴中收集到的物质来自当地。在较年轻的层面上,没有植被或初始演替,颗粒运输主要通过跃移(63 - 75%),风沙堆积速率平均为5000 - 7400 g m⁻² yr⁻¹(50%在3600至13400 g m⁻² yr⁻¹之间)。这比平坦的冰河湖外冲平原表面高出几倍,比完全被植被覆盖且离羽流区更远的较老层面高出6 - 44倍。这里的矿物颗粒更细,主要以悬浮形式运输(50 - 85%)。确定欧洲低地冰川湖溃决洪水形成的类似更新世冰河湖外冲平原锅穴内的风沙相和颗粒特征,可能表明它们由气候变暖、斯堪的纳维亚冰盖消退以及生态系统从苔原向森林转变所导致的形成时间。