An investigation of thermohaline circulation in Terra Nova Bay polynya
An investigation of thermohaline circulation in Terra Nova Bay polynya
复制标题
特拉诺瓦湾冰间湖温盐环流的调查
作者：
G. Buffoni;A. Cappelletti;P. Picco
本文研究了特拉诺瓦湾（南极洲罗斯海）沿海冰间湖的存在引起的温盐环流和对流过程。通过海洋观测和数值模拟来分析这些过程。水文参数和水流的时间序列显示了高盐度陆架水 (HSSW) 的形成以及水柱混合到很深的地方，以及动能的季节性循环。已经实现了二维时间相关模型，用于数值模拟冰间湖对环流的影响。该模型可以估计温盐强迫对环流模式的贡献、与观测到的盐度分布一致的产冰量、水流的年度周期以及 HSSW 出口量。冰间湖产生的温盐强迫能够在冰间湖区域附近诱发高达 40 cm s−1 的强水平水流，以及 1 cm s−1 量级的垂直运动。年产冰量从 45 m 到 90 m 不等，与深达 750 m 的水柱混合，并将地表进水的盐度增加至 34.82。 HSSW 向东北方向的净输送量估计为 0.34 Sv 至 1.23 Sv，具体取决于冰产量。
This paper addresses the study of the thermohaline circulation and convective processes induced by the presence of a coastal polynya in Terra Nova Bay (Ross Sea, Antarctica). These processes are analysed by means of oceanographic observations and numerical simulations. Time series of hydrological parameters and currents show the High Salinity Shelf Water (HSSW) formation with the mixing of the water column down to great depths, and a seasonal cycle of kinetic energy. A two-dimensional time dependent model for the numerical simulation of the effects of polynya on the circulation has been implemented. This model allows estimation of the contribution of thermohaline forcing on the circulation pattern, the amount of ice production consistent with the observed salinity distribution and annual cycle of currents and the amount of HSSW exported. The thermohaline forcing due to the polynya is able to induce strong horizontal currents up to 40 cm s−1 near the polynya area, as well as vertical movements of the order of 1 cm s−1. An annual ice production, ranging from 45 m to 90 m, mixes the water column at great depths, up to 750 m, and increases the salinity of the surface incoming waters up to 34.82. The estimated net north-eastward transport of HSSW ranges from 0.34 Sv to 1.23 Sv, depending on ice production.