Postdoctoral Fellowship: OPP-PRF: Tracking Long-Term Changes in Lake Area across the Arctic

北极的湖泊和池塘比世界上任何地方都多。这些湖泊为野生动物提供栖息地，并支持土著社区的生计活动。北极湖泊也是气候系统的重要组成部分。湖泊面积的变化可能会加强或减少气候变化的反馈，这取决于湖泊是扩大还是缩小。此前的研究表明，气候变化正在导致北极湖泊面积发生变化，但总体趋势尚不清楚。该项目利用高分辨率卫星数据评估北极地表水变化的方向和幅度。根据项目结果，PI将制定一套跟踪北极湖泊面积变化的最佳实践，并确定五个北极地区的湖泊是在扩大还是缩小。本研究旨在通过增进对年际变化的理解和制定确定北极地表水长期趋势的方法来减少北极湖泊面积变化幅度和方向的不确定性。研究人员将使用Planet（3米）图像生成北极五个地区地表水的多年高分辨率地图：北极沿海平原、育空-Kuskokwim三角洲、育空地区平原、麦肯齐河三角洲和Tuktoyaktuk半岛。这些高分辨率地图将用作量化现有粗分辨率（即，陆地卫星和中分辨率成像分光仪）地表水产品。根据这种方法学比较的结果，研究人员将开发一套最佳实践，以粗略的分辨率跟踪北极湖泊面积的变化（例如，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

There are more lakes and ponds in the Arctic than anywhere else in the world. These lakes provide habitat for wildlife and support the subsistence activities of Indigenous communities. Arctic lakes are also an important component of the climate system. Changes in lake area could strengthen or reduce climate change feedbacks, depending on whether lakes expand or shrink. Previous research shows that climate change is causing Arctic lake area to change, but the overall trend is unclear. This project uses high-resolution satellite data to assess the direction and magnitude of surface water change in the Arctic. Based on project findings, the PI will develop a set of best practices for tracking Arctic lake area change and determine whether lakes are expanding or shrinking in five Arctic regions. This research aims to reduce uncertainties in the magnitude and direction of Arctic lake area change by advancing understanding of interannual variation and developing a methodological approach to identify long-term trends in Arctic surface water. The researcher will use Planet (3 m) images to generate multi-year high resolution maps of surface water in five Arctic regions: the Arctic Coastal Plain, the Yukon-Kuskokwim Delta, the Yukon Flats, the Mackenzie River Delta, and the Tuktoyaktuk Peninsula. These high-resolution maps will be used as a reference for quantifying the accuracy and sensitivity of existing coarse resolution (i.e., Landsat and MODIS) surface water products. Based on the outcome of this methodological comparison, the researcher will develop a set of best practices for tracking Arctic lake area change with coarse resolution (e.g., Landsat) images, and, in regions where previous work is inconclusive, determine whether lake area has increased or decreased over the past twenty years.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.