Collaborative Research: Profiling ALACE Floats for the Subpolar Gyre in Support of the Atlantic Circulation and Climate Experiment (ACCE)

9531880戴维斯与伍兹霍尔海洋研究所的Brechner Owens博士的一个合作项目，将作为大西洋环流和气候实验的一部分，测量亚极环流1500米上部的绝对速度和温度和盐度结构的演变。绝对速度将使用均匀部署在盆地上的浮动阵列在标称深度400米和1500米处绘制地图。速度数据将处理亚极涡旋内经向翻转环流(MOC)的三条主要路径：浅层水流入水团修改区；形成新的稠密水的对流；以及由此产生的中间水从该源区流出。温度和盐度剖面将描述上部1500米的时间演变，从而能够量化MOC温暖水域分支的水团修改速率，该分支为深层和中层水的形成提供水。这些观测在两年中大约每十天观测一次150个剖面，将以比所有其他ACCE观测所能提供的更高的时间和空间分辨率描述演变，特别是在其他观测极其稀缺的冬季对流季节。对这些数据的分析将提供ACCE野外实验期间亚极涡旋上部1500米内的速度、温度和盐度场的时间序列图。此外，统计分析将提供平均环流和数量的空间分布，如涡动动能和势能、涡旋混合以及热量和淡水通量。这些环流范围的估计将为未来的气候模式提供强有力的约束，必须发展这些模式，以充分包括亚极环流的物理，特别是对流。绝对速度测量还将用于参考从该地区水文地质获得的大尺度地转切变，该地区普遍存在强烈的正压成分。

9531880 Davis In conjunction with a companion project by Dr. Brechner Owens of the Woods Hole Oceanographic Institution, 150 profiling ALACE (Autonomous Lagrangian And Circulation Explorer) floats will measure the absolute velocity and evolution of the temperature and salinity structure of the upper 1500 m in the subpolar gyre as part of the Atlantic Circulation and Climate Experiment (ACCE). Absolute velocities will be mapped at nominal depths of 400 and 1500 meters' depth using float arrays deployed uniformly over the basin. The velocity data will address three major pathways of the meridional overturning circulation (MOC) within the subpolar gyre: the shallow inflow of water into the regions of water mass modification; the convection that forms new dense waters; and the outflow of the resultant intermediate water from this source region. Temperature and salinity profiling will describe time evolution of the upper 1500 m, allowing quantification of the rates of water-mass modification in the warm-water limb of the MOC that supplies water for formation of deep and intermediate water. With 150 profiles observed roughly every ten days over two years, these observations will describe evolution with a combined temporal and spatial resolution greater than can be provided by all the other ACCE observations, especially over the winter-time convection season when other observations are extremely scarce. Analysis of these data will provide time series of three-dimensional maps of the velocity, temperature, and salinity fields within the upper 1500 m of the subpolar gyre over the duration of the ACCE field experiment. Additionally, statistical analyses will provide spatial distributions of mean circulation and quantities like eddy kinetic and potential energies, eddy mixing, and fluxes of heat and freshwater. These gyre-wide estimates will provide strong constraints for the future climate models that must be developed to adequately include the physics of the subpolar gyre, particularly convection. The absolute velocity measurements will also be used to reference large-scale geostrophic shears obtained from hydrography in this region where strong barotropic components are common.