Abstract Determining the path of river intrusions into lakes is essential, both for a better understanding of the lake circulation as well as the nutrient transport and the distribution of pollutants introduced by the rivers. The objective of this study is to understand the mixing of Rhone River water within Lake Geneva. The stable H- and O-isotope composition of water for this alpine lake has been shown to be a powerful tool to trace the Rhone River intrusion within the lake, but the details of this interflow and how it changes in space and time have not been well established yet. The present study focusses on using the isotopic tracer method in detailed cross-sections sampled at different times during the year as a tool to determine how the interflow changes with time. Different sampled cross-sections present large spatiotemporal heterogeneities of the Rhone River water dispersion. During summer and early autumn, when the lake is thermally stratified, the Rhone River is intruding into the metalimnion as an interflow, and it is directed by the currents in the top layer. The stronger the thermal stratification, the more concentrated and vertically constrained will also be the Rhone interflow. Vertical and horizontal displacements of the interflow are controlled by wind-induced internal waves and the gyres within the lake established as a function of wind strengths and directions.

中文翻译：

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日内瓦湖罗纳河水的混合：使用稳定同位素组成的季节性示踪

摘要 确定河流入侵湖泊的路径对于更好地了解湖泊环流以及河流引入的污染物的营养运输和分布至关重要。本研究的目的是了解日内瓦湖内罗纳河水的混合情况。这个高山湖水的稳定 H 和 O 同位素组成已被证明是追踪罗纳河在湖内入侵的有力工具，但这种相互流的细节以及它如何在空间和时间上的变化尚未确定还不错。本研究的重点是在一年中不同时间采样的详细横截面中使用同位素示踪剂方法作为确定互流如何随时间变化的工具。不同的采样横截面呈现出罗纳河水分散体的巨大时空异质性。在夏季和初秋，当湖泊热分层时，罗纳河作为互流侵入金属层，并由顶层的水流引导。热分层越强，罗纳河内流也就越集中和垂直约束。相互流的垂直和水平位移由风引起的内波和湖内的环流控制，该环流作为风强度和方向的函数而建立。热分层越强，罗纳河内流也就越集中和垂直约束。相互流的垂直和水平位移由风引起的内波和湖内的环流控制，该环流作为风强度和方向的函数而建立。热分层越强，罗纳河内流也就越集中和垂直约束。相互流的垂直和水平位移由风引起的内波和湖内的环流控制，该环流作为风强度和方向的函数而建立。