NNA Track 1: Rain on Snow and Extreme Precipitation Events across the Arctic and their Impacts on Social-Ecological Systems

导航新北极（NNA）是美国国家科学基金会的十大构想之一。NNA项目解决快速变化的北极地区的融合科学挑战。北极研究需要为国家、更大地区和全球的经济、安全和复原力提供信息。NNA支持从地方到国际规模的新研究伙伴关系，使下一代北极研究人员多样化，并整合知识的共同生产。这个奖项部分实现了这一目标。雨雪（ROS）和极端降水事件对北极野生动物、牲畜和依赖这些资源生存的社区产生了重大影响。ROS事件和深雪后形成的冰壳会干扰旅行和寻找食物。活性氧事件与驯鹿和北美驯鹿的大规模死亡有关。北极熊和环斑海豹的数量也受到了影响——繁殖季节早期的降雨破坏了雪下的洞穴，增加了幼崽的死亡率。本研究的目的是为了更好地了解整个北极地区ROS和极端降水事件的频率和原因，它们的频率和严重程度如何随着北极变暖而变化，以及它们的社会生态影响。这项研究主要关注狩猎和驯鹿放牧的生计，涉及与土著猎人和牧民的密切合作。将利用各种类型的卫星数据、大气再分析的天气数据和地面观测来探测ROS和极端降水事件。土著猎人和牧民将通过广泛的当地观察、访谈、小组讨论和参与性研讨会参与进来，以验证检测算法，并评估活性氧和极端降水事件对野生动物和社区活动的影响。同样，该项目将与驯鹿牧民合作，以更好地了解现代冻土带驯鹿游牧和死亡事件的影响，这些事件足以进入口头记录。将开发专家系统模型，以评估ROS和极端降水事件如何在事件时间、地理规模、积雪/土地覆盖和现有社区实践方面影响野生动物、迁徙驯鹿放牧、狩猎和其他社区活动。一个数据和知识中心，作为项目网站和关于北极ROS和极端降水事件及其影响的知识状况的资源，将成为该项目对美国北极观测网络的延伸。该项目还与美国国家科学基金会的ELOKA（北极地方观测和知识交流）项目密切相关，并与因纽特猎人、阿拉斯加北部社区以及拉普兰和俄罗斯的应用社区生态研究进行长期/正在进行的研究合作。该奖项反映了美国国家科学基金会的法定使命，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。

Navigating the New Arctic (NNA) is one of NSF's 10 Big Ideas. NNA projects address convergence scientific challenges in the rapidly changing Arctic. The Arctic research is needed to inform the economy, security and resilience of the Nation, the larger region and the globe. NNA empowers new research partnerships from local to international scales, diversifies the next generation of Arctic researchers, and integrates the co-production of knowledge. This award fulfills part of that aim. Rain on Snow (ROS) and extreme precipitation events have significant impacts on Arctic wildlife, livestock, and the communities that depend on these resources for subsistence. The icy crusts that form after ROS events and deep snow can interfere with travel and searching for food. ROS events have been linked to massive die-offs of reindeer and caribou. Polar bear and ringed seal populations are also affected--rains early in the breeding season destroy dens built under the snow and increase cub/pup mortality. The purpose of this study is to better understand the frequency and cause of ROS and extreme precipitation events across the Arctic, how their frequency and severity are changing as the Arctic warms, and their social-ecological impacts. With a primary focus on hunting and reindeer herding livelihoods, this study involves close collaborations with Indigenous hunters and herders. ROS and extreme precipitation events will be detected using various types of satellite data, weather data from atmospheric re-analyses, and surface observations. Indigenous hunters and herders will be engaged through extensive local observing, interviews, group discussions, and participatory workshops to validate the detection algorithms, and to assess effects of ROS and extreme precipitation events on wildlife and community activities. Similarly, the project will partner with reindeer herders to better understand implications for modern tundra reindeer nomadism and mortality episodes significant enough to have entered the oral record. Expert systems models will be developed to assess how ROS and extreme precipitation events impact wildlife, migratory reindeer herding, hunting, and other community activities in terms of event timing, geographic scale, snow/land cover, and existing community practices. A Data and Knowledge Hub, serving as the project website and a resource on the state of knowledge regarding Arctic ROS and extreme precipitation events and their impacts, will become the project's extension to the US Arctic Observing Network. The project also closely connects with the NSF ELOKA (Exchange for Local Observations and Knowledge of the Arctic) project, and long-time/on-going research collaboration with Inuit hunters, communities across Northern Alaska, and applied community-based ecological research in Lapland and Russia.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.