Cryogenic stage for laser microscope

激光显微镜低温载物台

• 批准号: 390835-2010
• 负责人: Halden, Norman
• 金额: $ 2.76万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments - Category 1 (<$150,000)
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=443300
• 关键词: Cryogenic; stage; laser; microscope

Arctic sea-ice is disappearing rapidly, this is going to have a profound impact on global climate, carbon cycling and sequestration calculations, and biological and human systems, particularly in the Arctic and on the continental shelf. The processes that dictate the atmosphere-ocean cycling of CO2 in sea-ice dominated environments are not well understood and constitute a critical gap in our understanding of the global carbon cycle. Uptake by polar seas is thought to be 2-3 times higher than the global ocean average where high rates of uptake are attributed to seasonal algal blooms in cold nutrient rich water and brine-driven convection associated with rapid ice formation. This process allows for carbon taken in at the surface to be transported to the deep ocean. "Frost flowers" growing on first year sea-ice are significantly mineralized; they contain CaCO3 (often as ikaite). Using laser ablation inductively coupled plasma mass spectrometry we will analyze the mineral content of the ice inclusions in situ and at different depths in ice cores. We expect to establish the 1) source of the major elements making up the mineral inclusions; 2) establish the sequence of mineral development and compositional evolution of the inclusion system at different depths in the ice; 3) relate composition and age to assess the effectiveness of the pumping model in different thicknesses of ice; and 3) test whether inclusion assemblages (including trace elements) trace elements can be used to source the sea-ice geographically. A parallel study will model elemental exchange in experimentally grown sea-ice and in Prairie saline lakes, which have remarkably similar ecology and mineralogy. It is crucial that we provide the best estimates we can for mass balance(s) involving carbon fluxes in the Arctic sea-ice system. The mineralogical content of sea ice has essentially gone unaccounted in this system. Without the mineralogical data our estimates of CO2 and Ca cycling will be wrong.

北极海冰正在迅速消失，这将对全球气候、碳循环和固存计算以及生物和人类系统产生深远影响，特别是在北极和大陆架。在以海冰为主的环境中，决定二氧化碳的大气-海洋循环的过程尚未得到很好的理解，这构成了我们对全球碳循环理解的一个关键鸿沟。极地海洋的摄取量被认为是全球海洋平均摄取量的2-3倍，后者的高摄取率归因于寒冷营养丰富的水中的季节性藻类水华以及与快速结冰有关的盐水驱动的对流。这一过程允许从表面吸收的碳被输送到深海。生长在第一年海冰上的“霜花”被显著矿化；它们含有CaCO3(通常是伊卡伊石)。利用激光烧蚀电感耦合等离子体质谱技术，对冰芯中不同深度的冰包裹体的矿物含量进行现场分析。我们期望建立1)组成矿物包裹体的主要元素的来源；2)建立冰中不同深度包裹体系统的矿物发育和成分演化序列；3)联系成分和年龄来评估不同厚度冰的抽水模式的有效性；3)检验包裹体组合(包括微量元素)是否可以从地理上为海冰提供来源。一项平行的研究将模拟实验生长的海冰和草原盐湖中的元素交换，这两个湖的生态和矿物学非常相似。至关重要的是，我们要对涉及北极海冰系统碳通量的物质平衡(S)提供最好的估计。在这个系统中，海冰的矿物学含量基本上是下落不明的。没有矿物学数据，我们对二氧化碳和钙循环的估计将是错误的。