Ice wedges as winter climate archives - towards high-quality chronologies, advanced process understanding and new paleoclimate records

北极永久冻土区的冰楔是很有希望的气候档案。在稳定水同位素中，它们保存了数千年的冬季气候信息，而其他气候档案没有或只是没有充分涵盖这些信息。然而，这些信息对于全面了解过去的气候变化是至关重要的。拟议的项目旨在建立作为气候档案的冰楔，并提供新的气候重建。这将通过更好地了解控制过程和改进方法来实现。该项目基于西伯利亚北极几个研究地点现有的一组冰楔数据以及其他气象和同位素数据。为了获得更好的冰楔年代学，将评估不同碳组分(宏观化石遗骸、溶解的二氧化碳)的放射性碳年龄，并将其与当地永久冻土地层学联系起来。发展冰楔生长模式，提供高分辨率的冰楔同位素时间序列，通过对冰楔形成过程中同位素分馏的分析，提高对冰楔同位素气候信号的认识。结合当地气象资料，对冰楔同位素数据进行温度刻度，结合改进的测年方法和对同位素信号的理解，开发和解释新的高质量古气候时间序列，并结合其他古气候记录和气候模式输出。

Ice wedges from Arctic permafrost regions are promising climate archives. In stable-water isotopes they preserve over millennia winter climate information that is not or only inadequately covered by other climate archives. This information,however, is essential for a comprehensive seasonal understanding of past climate variability.The proposed project aims at establishing ice wedges as climate archives and at providing new climate reconstructions. This will be achieved through a better understanding of the controlling processes and an advancement of methodical approaches. The project is based on an already existing set of ice-wedge data from several study sites in the Siberian Arctic and additional meteorological and isotope data.To derive better ice-wedge chronologies radiocarbon ages from different carbon fractions (macrofossil remains, dissolved, CO2) will be assessed and linked to local permafrost stratigraphies. Ice-wedge growth models will be developed to provide high-resolution ice-wedge isotope time series.The understanding of the ice-wedge isotope climate signal will be improved by the analysis of isotope fractionation during ice-wedge genesis. Considering local meteorological data ice-wedge isotope data will be calibrated to temperatures.By linking improved dating approaches and improved understanding of isotope signals new high-quality paleoclimate time series will be developed and interpreted considering other paleoclimate records and climate model output.