SGER: Exploration of a Tracer Patch in the Tropical Atlantic and Caribbean Sea

热带大西洋和加勒比海示踪斑块的探索。提出了2001年在热带大西洋和加勒比海发布的示踪剂斑块的ledwellwhoissampling。取样的主要目的是量化示踪剂在热带大西洋中惊人的大纬向扩散，并测量示踪剂在加勒比海背斜区的横向扩散，那里对盐指化的敏感性几乎与巴巴多斯东部一样大，但温盐阶梯很少。其他重要的目标是确定巴巴多斯东部阶梯区示踪剂分布明显下沉的性质，获得该地区2年的内环流扩散率测量值，并确定示踪剂斑块2年向西的范围。对大西洋和加勒比地区纬向弥散的探索将提供独特的数据，用于比较海洋环流模式，并可能有助于提高对亚热带锋切变的认识。在加勒比海测量横旋扩散率将改善混合作为密度比函数的参数化，即作为温度和盐度梯度的函数，在高切变的盐指有利区域。该调查的所有目标都是探索性的，此外，由于示踪剂补丁将在研究区域内传播和扫过的速度，因此暂时紧急请求支持。抽样应在2003年进行。

Exploration of a Tracer Patch in the Tropical Atlantic and Caribbean SeaJ. LedwellWHOISampling of a tracer patch released in 2001 in the tropical Atlantic Ocean and Caribbean Sea is proposed. The main goals of the sampling are to quantify the surprisingly large zonal dispersion of the tracer in the tropical Atlantic, and to measure the diapycnal diffusivity of the tracer in the pycnocline of the Caribbean, where susceptibility to salt fingering is nearly as great as east of Barbados, but where thermohaline staircases are rare. Other important goals are to determine the nature of the apparent sinking of the tracer distribution in the staircase region east of Barbados, to obtain a 2-year measurement of the diapycnal diffusivity there, and to determine the westward extent of the tracer patch at 2 years. Exploration of zonal dispersion in both the Atlantic and Caribbean will provide unique data with which to compare models of ocean circulation, and may help to improve knowledge of shear across the subtropical front. Measurement of diapycnal diffusivity in the Caribbean will improve parameterizations of mixing as a function of density ratio, i.e., as a function of temperature and salinity gradients, in salt-finger favorable regions with high shear. The nature of the survey is exploratory in all of its goals, and furthermore, the request for support is temporally urgent because of the speed with which the tracer patch will spread and be swept through the region of the study. Sampling should be done in 2003.