Past, present, and future glacier evolution in the Tropical Andes

极地冰盖外的冰川和冰帽受到气候变化的强烈影响，各种可观测数据被定义为基本气候变量。冰川萎缩对水文、生态系统和社会有局部到区域的影响。在热带安第斯山脉，冰川是一种重要的水资源，对当地和区域的供水有重大贡献，特别是在旱季和干旱期间。此外，冰川退缩增加了冰川湖暴发洪水的风险，将下游社区置于危险之中。为了改进未来的水管理和风险评估，以及评估气候变化的影响，需要关于热带安第斯山脉过去、现在和未来冰川演变的区域范围的详细信息。目前的冰川质量变化估计具有时空局限性，而且往往存在相当大的不确定性，而在全球分析范围内进行的区域预测显示出部分模糊的趋势。该项目旨在通过全面分析热带安第斯山脉过去、现在和未来的冰川演化来克服这些不足。将根据多任务遥感数据、现场测量以及冰川和水文模型的创新组合，对当前和未来的冰川变化进行改进的区域评估。结合利用独特的遥感档案获得的关于过去冰川变化的数据，将有助于评估长期趋势及其与气候变化的关系。通过将新的遥感产品和现场观测同化到冰动力模型反演中，将产生高度改进的冰量分布信息。将使用质量平衡模型预测热带安第斯山脉到2100年的冰川演变，并对热带地区进行优化，并进行全三维冰川模型预测，以克服现有全球估计数的缺点。这些活动将有助于随后研究冰川湖泊演化和冰川融水对集水径流的贡献。该项目的成果将包括关于热带安第斯山脉冰川演变的新的和改进的区域信息以及方法上的进步。这些活动包括：(1)加强对正在进行的冰川变化的全区域量化，评估其长期趋势及其与气候变化的相关性；(2)开发创新的遥感和建模技术；(3)利用完全耦合、三维分布和优化的建模，改进冰川和径流演变的信息和预测。

Glaciers and ice caps outside the polar ice sheets are strongly affected by climate change, and various observables are defined as essential climate variables. Glacier shrinkage has local to regional-scale impacts on hydrology, ecosystems, and society. In the Tropical Andes, the glaciers pose an important water resource and significantly contribute to the local and regional water supply, especially during the dry season and drought periods. Moreover, glacier retreat increases the risk of glacier lake outburst floods putting downstream communities at risk. To improve future water management and risk assessment as well as to evaluate the impact of climate variations, region-wide and detailed information on the past, present, and future glacier evolution in the Tropical Andes is required. Current glacier mass change estimates have spatiotemporal limitations and often considerable uncertainties, while regional projections, carried out within global analyses, show partly ambiguous trends. This project aims to overcome these deficiencies by comprehensively analyzing the Tropical Andes' past, present, and future glacier evolution. An improved regional assessment of current and future glacier changes will be conducted based on an innovative combination of multi-mission remote sensing data, in-situ measurements, and glacier and hydrological modeling. In combination with data on past glacier changes, which are obtained by exploiting unique remote sensing archives, the evaluation of the long-term trend and its relation with climate change will be facilitated. By assimilating the new remote sensing products and in-situ observations into an ice-dynamic model inversion, highly improved ice volume distribution information will be generated. Projections of glacier evolution for the Tropical Andes until 2100 using mass balance modeling, optimized for the tropics, and fully 3-dimensional glacier modeling will be conducted to overcome the shortcomings of existing global estimates. Those activities will facilitate the subsequent study of the glacier lakes evolution and the glacier meltwater contribution to catchment runoff. The outcomes of this project will include novel and improved regional information regarding the glacier evolution in the Tropical Andes and methodological advances. These comprise (1) region-wide enhanced quantification of the ongoing glacier changes, the evaluation of its long-term trend and correlation with climatic variations, (2) development of innovative remote sensing and modeling techniques, (3) improved ice thickness information and projections of glacier and runoff evolution using fully coupled, 3D-distributed and optimized modeling.