The interaction between sea ice, ocean biogeochemistry and ecosystem function

北极冰冻圈最近的许多变化都是戏剧性的，甚至超过了对未来变化的最极端的预测。其中一些冰冻圈的变化预计将通过遥远的联系影响当地、地区甚至全球气候。然而，与不断变化的冰冻圈相关的气候反馈是极其复杂的，随着空间和时间的变化而变化，而且通常仍然知之甚少。我的计划的长期目标是了解气候引起的海冰和淡水动态变化如何改变海洋北极的生物地球化学和生态功能。这将为确定极地海洋在缓冲气候活跃气体排放方面的作用提供至关重要的见解。将特别注重确定冰藻群落在支持气候变化反馈机制方面的作用。这些独特的微生物群落在海冰的极端生物群中茁壮成长，有助于有机物质、营养物质和气候活跃气体的形成和循环。然而，人们对冰藻生态及其在海-海-冰-大气交换中的潜在重要作用知之甚少。我将探索和量化与冰相关的微生物群落的代谢活动。我的计划的短期目标是确定冰藻群落在支持气候变化反馈机制方面的作用。为了实现这一目标，我将：1.解决海冰(冰、盐水、气体、生物群)在冰冻和融化循环期间的复杂三维结构；2.量化这如何影响自养冰藻群落的光条件和净群落新陈代谢，控制冰藻在有机质释放、热量收支和海洋与大气之间的二氧化碳交换中的作用。3.在该项目期间培养2名博士、2名硕士和5名本科生。该项目的发现将有助于改进北极海冰对北极作为二氧化碳汇和辐射强迫产生器的作用的现有模型，从而改进区域和全球气候模型。

Many recent changes in the Arctic cryosphere have been dramatic and have exceeded even the most extreme projections of future change. Some of these cryosphere changes are expected to affect local, regional and even global climate through distant connections. However, climate feedbacks associated with the changing cryosphere are extremely complex, vary over space and time, and are still generally poorly understood. The long-term goal of my program is to understand how climate-induced changes in sea ice and freshwater dynamics transform the biogeochemical and ecological function of the marine Arctic. This will provide critical insight for defining the role of the polar oceans in buffering emissions of climate-active gasses. Special focus will be allocated to determine the role of ice algal communities in supporting feedback mechanisms with climate change. These unique microbial communities thrive within the extreme biome of the sea ice and contribute to the formation and cycling of organic material, nutrients and climate active gasses. However, very little is known about ice algal ecology and the potentially important role that they play in ocean–sea ice–atmosphere exchange. I will explore and quantify the metabolic activity of ice-associated microbial communities. The short-term goal of my program is to determine the role of ice algal communities in supporting feedback mechanisms with climate change. To achieve this goal I will: 1. Resolve the complex 3-D structure of sea ice (ice, brine, gasses, biota) during ice freeze and thawing cycles; 2. Quantify how this affects light conditions for the autotrophic ice algal community and net community metabolism governing ice algae's role in organic matter release, thermal budget and CO2 exchange between the ocean and atmosphere. 3. Train 2 PhD, 2 MSc and 5 undergraduate students during this project. The project findings will be instrumental in improving current models of Arctic sea ice effects on the role of the Arctic as a CO2 sink and generator of radiative forcing, thereby improving regional and global climate models.