LTER Palmer, Antarctica (PAL): Land-Shelf-Ocean Connectivity, Ecosystem Resilience and Transformation in a Sea-Ice Influenced Pelagic Ecosystem

帕尔默南极长期生态研究站自1990年以来一直在运行。 所有LTER站点的目标是对需要数十年数据并覆盖广大地理区域的生态问题进行与政策有关的研究。 对于帕尔默南极LTER，问题集中在南极洲半岛以西的海洋生态系统如何应对地球上任何地方一样迅速变化的气候。例如，过去35年的卫星观测表明，海冰覆盖的平均持续时间现在约为90天（3个月！）比原来短 开放水域的延长对生态系统研究的许多方面都有影响，该地区阿德利企鹅的减少经常被引用为南极洲气候变化影响的一个例子。先进的技术，如自主水下（可能是空中）车辆，海底系泊和数值模拟，加上每年的海洋学巡航，每周的环境采样，使帕尔默南极LTER能够扩大和桥接评估气候影响所需的时间和空间尺度。该奖项包括首次研究鲸鱼作为季节性海冰区生态系统中主要捕食者的作用。该团队还将关注海底峡谷，增强生物活动的特殊区域，沿着南极西部半岛（WAP）。当前奖项的首要研究问题是：季节性，年际变化，以及海冰范围和持续时间的长期趋势如何影响海洋生态系统和生物地球化学循环的结构和动态？在广泛的问题中的具体焦点包括：1。长期变化和生态系统转型。作为生态系统状态的函数，生态系统对外部扰动的敏感性或恢复力是什么？2.横向连通性和垂直分层。淡水、热量和营养物质的横向输送对当地海洋分层和生产力有何影响，它们如何推动生态系统的变化？3.自上而下的控制和移动基线。生态系统如何应对捕鲸的停止和随后鲸鱼种群的长期恢复？4.食物网结构和地球化学过程。食物网结构的时间和空间变化如何影响碳和养分循环、输出和储存？该奖项的更广泛影响利用当地的教育合作伙伴关系，包括三明治，MA STEM学院，新英格兰水族馆，以及美国国家科学基金会资助的哥伦比亚地球研究所的极地学习和应对（PoLAR）气候变化教育伙伴关系，以建立北极和南极，海洋和陆地科学家和学生，政府和非政府组织之间的新的协同作用。帕尔默南极LTER还将进行适当的跨LTER站点比较，并作为信息管理的领导者，以促进南极、海洋和LTER社区内外的知识建设。

The Palmer Antarctica LTER (Long Term Ecological Research) site has been in operation since 1990. The goal of all the LTER sites is to conduct policy-relevant research on ecological questions that require tens of years of data, and cover large geographical areas. For the Palmer Antarctica LTER, the questions are centered around how the marine ecosystem west of the Antarctica peninsula is responding to a climate that is changing as rapidly as any place on the Earth. For example, satellite observations over the past 35 years indicate the average duration of sea ice cover is now ~90 days (3 months!) shorter than it was. The extended period of open water has implications for many aspects of ecosystem research, with the concurrent decrease of Adèlie penguins within this region regularly cited as an exemplar of climate change impacts in Antarctica. Cutting edge technologies such as autonomous underwater (and possibly airborne) vehicles, seafloor moorings, and numerical modeling, coupled with annual oceanographic cruises, and weekly environmental sampling, enables the Palmer Antarctica LTER to expand and bridge the time and space scales needed to assess climatic impacts. This award includes for the first time study of the roles of whales as major predators in the seasonal sea ice zone ecosystem. The team will also focus on submarine canyons, special regions of enhanced biological activity, along the Western Antarctic Peninsula (WAP).The current award's overarching research question is: How do seasonality, interannual variability, and long term trends in sea ice extent and duration influence the structure and dynamics of marine ecosystems and biogeochemical cycling? Specific foci within the broad question include: 1. Long-term change and ecosystem transitions. What is the sensitivity or resilience of the ecosystem to external perturbations as a function of the ecosystem state? 2. Lateral connectivity and vertical stratification. What are the effects of lateral transports of freshwater, heat and nutrients on local ocean stratification and productivity and how do they drive changes in the ecosystem? 3. Top-down controls and shifting baselines. How is the ecosystem responding to the cessation of whaling and subsequent long-term recovery of whale stocks? 4. Foodweb structure and biogeochemical processes. How do temporal and spatial variations in foodweb structure influence carbon and nutrient cycling, export, and storage? The broader impacts of the award leverage local educational partnerships including the Sandwich, MA STEM Academy, the New England Aquarium, and the NSF funded Polar Learning and Responding (PoLAR) Climate Change Education Partnership at Columbia's Earth Institute to build new synergies between Arctic and Antarctic, marine and terrestrial scientists and students, governments and NGOs. The Palmer Antarctic LTER will also conduct appropriate cross LTER site comparisons, and serve as a leader in information management to enable knowledge-building within and beyond the Antarctic, oceanographic, and LTER communities.