Deep water exchange in the Baltic Proper
Deep water exchange in the Baltic Proper
复制标题
波罗的海本岸的深水交换
DOI：
10.3402/tellusa.v45i4.14895
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发表时间：
1993
期刊：
影响因子：
2
通讯作者：
A. Omstedt
中科院分区：
文献类型：
--
作者：
T. Kõuts;A. Omstedt
根据1970- 1990年期间测量的温度和盐度数据，分析了波罗的海本体的深水交换和混合特性。采用基本模式概念，如守恒原则、两层方法和地转流假设，对数据进行了分析。波罗的海深水区的更新包括上游盆地的流入。流入的稠密水被地表水稀释，从卡特加特海峡进入兰瑟特深海时，20年平均增加了4倍。三个主要的混合区被定位。首先，带海和声音，其中深水流入量增加了79%;其次，Arkona盆地，垂直混合导致深电流体积流量平均增加了53%;第三，在Stolpe通道，湍流夹带平均增加了28%的深电流。应用地转流模式对盐度资料进行处理，计算了深海流流速的时间序列。该模型通过根据守恒原理计算的20年平均流量进行校准。引入有效底床深度作为校正系数。结果发现，地转流模型描述深层流动在博恩霍尔姆海峡，但流量被低估的Stolpe渠道和高估的法鲁渠道。在Stolpe海峡和Faro海峡，深层流表现出季节性变化，分别在秋季和冬季迅速增加。DOI：10.1034/j.1600-0870.1993.t01-1-00006.x
Deep-water exchange and mixing properties in the Baltic Proper were analysed on the basis of temperature and salinity data measured during the period 1970–90. The data were analysed applying basic model concepts as the conservation principles, the two-layer approach and the geostrophic flow assumption. The renewal of the deep water in the Baltic Proper consists of inflow from upstream basins. The inflowing dense water is diluted by surface water and on a 20-year average increased by a factor of 4, when entering from the Kattegat into the Landsort Deep. Three main mixing zones were localized. Firstly, the Belt Sea and the Sound, where the deep-water inflow increases by 79%; secondly, the Arkona Basin, where vertical mixing causes the increase of deep current volume flow by an average of 53%; and thirdly, in the Stolpe Channel, where the turbulent entrainment adds an average of 28% to the deep current. Applying the geostrophic flow model on salinity data, time series of deep current flow rates were calculated. The model was calibrated by 20-year mean flows calculated from conservation principles. The effective sill depths were introduced as calibration coefficients. It was found that the geostrophic flow model described deep-layer flows in the Bornholm Channel well, but the flow rate was underestimated in the Stolpe Channel and overestimated in the Faro Channel. In the Stolpe Channel and in the Faro Channel, the deep-layer flow showed seasonal variations with rapid increase during the autumn and winter seasons, respectively. DOI: 10.1034/j.1600-0870.1993.t01-1-00006.x