Postdoctoral Fellowship: OPP-PRF: Linkages among Sea Ice, Phytoplankton, and Carbon in the Marginal Ice Zone

南极洲西部半岛是南极洲变暖最快的地区之一，通过影响浮游植物大量繁殖，影响从大气到海洋的碳通量，浮游植物是构成食物网基础的微小海洋植物。该项目调查了南极西部半岛变暖和海冰减少时浮游植物的季节性时间、数量和类型的变化。这项对一个至关重要的生态系统的碳循环和事件季节性变化的研究与面临全球气候变暖的所有极地系统有关。拟议的研究将扩大我们对气候变化对南极海冰损失速度最快的地区的初级生产和碳吸收的季节性时间的影响的理解。南大洋是全球碳预算的重要调节者，但关于浮游植物的作用仍有许多未知数。这项工作将着眼于浮游植物如何影响碳吸收的两个特点，这两个特点往往被忽视：浮游植物群落组成和物候（即，季节性事件的时间）。拟议工作的目标是评估物理和生物因素如何影响从大气到海洋的碳通量的季节性时间、幅度和长期趋势。研究人员将把在南极洲西部收集的数据与数值模型相结合，以测试事物发生变化的可能原因，并测试食物网基础上的特定变量。观测将用于评估长期变化，模型将用于调查观测到的变化的可能原因，如海冰、风、海洋物理、云量和浮游植物群落组成的变化。拟议工作的目标是（1）分析物候变化，（2）利用帕尔默长期生态研究计划的色素和流通成像数据调查浮游植物群落组成，（3）利用建模案例研究评估物候变化的可能原因，（4）通过模拟实验比较生物因子和物理因子对碳通量和物候变化的相对影响。外展和教育活动包括帕尔默长期生态研究（LTER）计划的博客和视频开发，本科生的指导，以及与极地扫盲原则保持一致的K-12课程计划开发。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

The West Antarctic Peninsula is one of the fastest warming regions in Antarctica, impacting carbon fluxes from the atmosphere to the ocean through effects on phytoplankton blooms, the microscopic marine plants that form the base of the food web. This project investigates changes in the seasonal timing, amount, and type of phytoplankton as the West Antarctic Peninsula warms and experiences sea ice loss. This study of a critically important ecosystem’s carbon cycle and shifting seasonal timing of events is relevant to all polar systems in the face of global climate warming. The proposed research will broaden our understanding of the impact of climate change on the seasonal timing of primary production and carbon uptake in a region experiencing the most rapid rate of sea ice loss in the Antarctic. The Southern Ocean is a massive regulator of the global carbon budget, but many unknowns remain about the role of phytoplankton. This work will look at two features of how phytoplankton influence carbon uptake that are often overlooked: phytoplankton community composition and phenology (i.e., the timing of seasonal events).The goal of the proposed work is to assess how physical and biological factors affect the seasonal timing, magnitude, and long-term trends of carbon flux from the atmosphere to the ocean. Researchers will incorporate data collected in West Antarctica with numerical modeling to test possible reasons why things are changing, and to test specific variables at the base of the food web. Observations will be used to evaluate long-term change, and models will be used to investigate likely causes for observed shifts, such as changes in sea ice, wind, ocean physics, cloudiness, and phytoplankton community composition. The objectives of the proposed work are to (1) analyze phenology shifts, (2) investigate phytoplankton community composition using pigment and flow-through imaging data from the Palmer Long-Term Ecological Research program, (3) evaluate possible reasons for shifts in phenology using modeling case studies, and (4) compare the relative impacts of biological factors versus physical factors on carbon flux and phenology shifts using modeling experiments. Outreach and education activities include blog and video development for the Palmer Long-Term Ecological Research (LTER) program, mentoring of undergraduate college students, and K-12 lesson plan development in alignment with Polar Literacy Principles.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.