Alpine permafrost index map

The objective of this study is the production of an Alpine Permafrost Index Map (APIM) covering the entire European Alps. A unified statistical model that is based on Alpine-wide permafrost observations is used for debris and bedrock surfaces across the entire Alps. The explanatory variables of the model are mean annual air temperatures, potential incoming solar radiation and precipitation. Offset terms were applied to make model predictions for topographic and geomorphic conditions that differ from the terrain features used for model fitting. These offsets are based on literature review and involve some degree of subjective choice during model building. The assessment of the APIM is challenging because limited independent test data are available for comparison and these observations represent point information in a spatially highly variable topography. The APIM provides an index that describes the spatial distribution of permafrost and comes together with an interpretation key that helps to assess map uncertainties and to relate map contents to their actual expression in terrain. The map can be used as a first resource to estimate permafrost conditions at any given location in the European Alps in a variety of contexts such as research and spatial planning.
Results show that Switzerland likely is the country with the largest permafrost area in the Alps, followed by Italy, Austria, France and Germany. Slovenia and Liechtenstein may have marginal permafrost areas. In all countries the permafrost area is expected to be larger than the glacier-covered area.

本研究的目标是绘制覆盖整个欧洲阿尔卑斯山区的阿尔卑斯多年冻土指数图（Alpine Permafrost Index Map, APIM）。本研究采用基于全阿尔卑斯区多年冻土观测数据的统一统计模型，对全区域内的碎屑物与基岩表面开展分析。该模型的解释变量包括年平均气温、潜在入射太阳辐射与降水量。为针对与模型拟合所用地形地貌特征存在差异的地形与地貌条件生成模型预测结果，研究引入了偏移项；此类偏移项基于文献综述推导得出，且在模型构建过程中存在一定程度的主观选择空间。阿尔卑斯多年冻土指数图的评估颇具挑战，原因在于可用的独立验证数据较为匮乏，且这些观测数据仅代表空间异质性极强的地形中的单点信息。阿尔卑斯多年冻土指数图提供了用于描述多年冻土空间分布的指数，并附带解译密钥，可辅助评估图件不确定性，同时帮助将图件内容与实际地形中的冻土分布特征相对应。该图可作为基础资源，在科研、空间规划等多种场景下，用于估算欧洲阿尔卑斯山区任意给定位置的多年冻土条件。
研究结果表明，瑞士或为阿尔卑斯山区多年冻土面积最大的国家，其次依次为意大利、奥地利、法国与德国；斯洛文尼亚与列支敦士登仅拥有少量零星的多年冻土分布区。在所有上述国家中，多年冻土面积预计均大于冰川覆盖面积。