Observations of Ice-Ocean Momentum and Heat Fluxes at the SHEBA Ice-Camp

9701797这个研究项目是一个名为SHEBA(北冰洋地表热量平衡)的大型、协调、多研究者项目的关键组成部分。SHEBA计划将在一个年度周期内同时测量大气、冰盖和上层海洋的各种通量和特性，这些通量和特性决定了北极海冰的总质量和能量收支。其目标是更好地理解北冰洋冰盖如何以及在多大程度上影响低纬度和全球气候模型中的气候变异性。为了实现这一目标，已经挑选了两个可能很重要的辐射/气候反馈过程进行研究：冰-反照率反馈和云-辐射反馈。该提案涉及SHEBA涉及冰--反照率反馈机制的一个海洋学部分。两台专门建造的声学多普勒海流剖面仪S将被部署来研究风和洋流在冰从一个地方到另一个地方移动中的作用。深度剖面系统由一个140 kHz、四波束编码的脉冲声纳组成。这将配置到400米，空间分辨率为3米。它将提供埃克曼层、深层混合层、中尺度和大尺度流动的准确图像。第二个，从冰上部署的五波束560 kHz通量声纳，将提供对冰下边界层湍流动量通量的直接估计。当结合共同定位的温度和盐度测量时，也可以估计湍流热通量。目的是在示巴难民营的整个12至13个月期间使用这两个工具。在舍巴的一套综合测量将允许改进北极地区的气候模型。这些改进的模型将导致更好地预测气候和北极冰盖在拟议的全球变暖下的持久性。如果大气中的二氧化碳水平增加到目前的水平，就可能发生全球变暖。

9701797 Pinkel This research project is a key component of a large, coordinated, multi-investigator program called SHEBA (Surface Heat Budget of the Arctic) Ocean. The SHEBA program will simultaneously measure, over an annual cycle, the various fluxes and properties of the atmosphere, ice pack, and upper ocean that determine the aggregate mass and energy budgets of Arctic sea ice. Its goal is improved understanding of how and to what extent, the ice covered Arctic Ocean affects climate variability in lower latitudes and in global climate models (GCMs). Towards that goal, two potentially important radiation/climate feedback processes have been singled out for study: Ice-Albedo Feedback and Cloud-Radiation Feedback. This proposal addresses an oceanographic component of SHEBA dealing with ice-albedo feedback mechanisms. Two specially constructed acoustic Doppler current profilers (ADCP)s will be deployed to investigate the roles of wind and ocean currents in moving ice from place to place. A Deep Profiling System consists of a 140 kHz, four beam coded pulse sonar. This will profile to 400 m with 3 m spatial resolution. It will provide an accurate picture of the Ekman layer, the deep mixed layer, meso and large scale flows. A second, five beam 560 kHz Flux Sonar deployed from the ice, will provide direct estimates of the turbulent momentum flux in the under-ice boundary layer. When coupled with co-located measurements of temperature and salinity, turbulent heat fluxes can be estimated as well. The intention is to run these two instruments for the full 12-13 month duration of the SHEBA camp. The combined set of measurements in SHEBA will allow refinement of climate models for the Arctic region. Those improved models will lead to better predictions of the climate and the permanence of the Arctic ice cap under a proposed global warming that could occur if atmospheric carbon dioxide levels are increased above present levels.