Ice-tethered profiling from the land-fast ice on the Arctic shelves

所要求的设备是一对ITP(冰系留剖面仪)、CTD(电导率-温度-深度)和浊度/叶绿素荧光/CDOM(有色溶解有机物)冰下剖面仪。ITP能够在海底和水-冰界面之间进行频繁的(每小时)垂直CTD和光学剖面图，垂直分辨率为~2-5厘米。这种廓线数据对于评估冰盖下垂直湍流交换的强度是必不可少的。预计国际冰盖方案将用于NSERC-DG的三个研究项目，题为“北极大陆架上陆地快速冰之下的垂直混合：效率和驱动机制”、“辐射强迫在不断变化的北极环境中对海冰融化-增长循环的作用”和“积雪覆盖的海冰的动力和热力学过程”。所要求的设备将取代现有的不可靠和不合适的设备，以对陆上坚冰下的水温、盐度和光学特性进行频繁和长期的自主剖析。现有的租借设备专为公海应用而设计，不适合在陆上坚冰上作业。相比之下，ITP只是专门为部署、频繁和持久的自主CTD和冰下浊度/叶绿素/CDOM剖面而设计的设备。从10月/11月至5月/6月，两台相距约15-20公里的ITP剖面仪与声学多普勒海流剖面仪(ADCP)一起部署在陆上快速冰上，历时约7个月。现场观测发生在哈德逊湾的大鲸河河口、加拿大群岛和格陵兰岛的决心航道和剑桥湾。每年都会在不同地点之间重新分配信息和通信技术方案和反兴奋剂方案。该项目将阐明在不同环境条件下不同北极大陆架上垂直混合的作用。这将大大提高我们对垂直混合的区域变化和北极大陆架陆上冰下不稳定的机制的理解，并可能对北极建模产生影响。这对加拿大北冰洋大陆架尤其重要，那里有望进行广泛的石油和天然气勘探。

The requested equipment is a pair of ITP (Ice-Tethered Profiler) CTD (Conductivity-Temperature-Depth) and turbidity/chlorophyll fluorescence/CDOM (Colored Dissolved Organic Matter) under-ice profilers. The ITPs are capable of frequent (hourly) vertical CTD and optical profiling between the sea floor and water-ice interface with vertical resolution of ~2-5 cm. Such profiling data are indispensable for assessing the intensity of the vertical turbulent exchange beneath the ice cover. The ITPs are expected to be used for three NSERC-DG research projects, entitled "Vertical mixing below the land fast ice on the Arctic shelves: Efficiency and driving mechanisms", "Role of radiative forcing on the sea ice melt-growth cycle in a changing Arctic environment" and "Dynamic and thermodynamic processes of snow covered sea ice". The requested equipment will replace existing unreliable and inappropriate equipment to conduct frequent and long-lasting autonomous profiling of water temperature, salinity, and optical characteristics below the land-fast ice. The existing loaned equipment designed for open ocean applications is unsuitable for operations from land-fast ice. In contrast, the ITP is only the equipment specifically designed for deployment, frequent and long-lasting autonomous CTD and turbidity/chlorophyll/CDOM profiling below the ice. The two ITP profilers separated by ~15-20 km are deployed from the land-fast ice in combination with Acoustic Doppler Current Profilers (ADCP) for ~ 7-month from October/November to May/June. The field observations take place at the Great Whale River Estuary in Hudson Bay, Resolute Passage and Cambridge Bay in the Canadian Archipelago and in Greenland. Every year, ITPs and ADCPs are reallocated between different locations. This project will clarify the role of vertical mixing on the different Arctic shelves for different environmental conditions. This will significantly improve our understanding of regional changes in vertical mixing and mechanisms responsible for instability below land-fast ice on Arctic shelves with potential implications for Arctic modeling. This is of particular importance for the Canadian Arctic shelf where the extensive exploration of oil and gas is expected.