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、碳循环和封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上。在海冰主导的环境中，决定大气-海洋二氧化碳循环的过程还没有得到很好的理解，这构成了我们对全球碳循环理解的一个关键空白。据认为，极地海洋的吸收量比全球海洋平均水平高2-3倍，而极地海洋的高吸收量是由于寒冷富营养水域的季节性藻华和与快速结冰有关的盐水驱动对流。这个过程允许从表面吸收的碳被运送到深海。生长在第一年海冰上的“霜花”明显矿化；它们含有碳酸钙（通常是碳酸钙）。利用激光烧蚀电感耦合等离子体质谱分析了冰芯中原位和不同深度冰包裹体的矿物含量。我们希望确定1)组成矿物包裹体的主要元素的来源；2)建立了冰中不同深度包裹体的矿物发育序列和成分演化；3)结合成分和年龄，评价泵送模型在不同冰厚条件下的有效性；3)检验包裹体组合（含微量元素）是否可用于海冰的地理来源。一个平行的研究将模拟实验生长的海冰和草原盐湖的元素交换，它们具有非常相似的生态和矿物学。至关重要的是，我们要尽可能提供有关北极海冰系统中碳通量的质量平衡的最佳估计。在这个系统中，海冰的矿物学含量基本上没有被计算在内。如果没有矿物学数据，我们对二氧化碳和钙循环的估计将是错误的。