Importance of planetary rotation for ventilation processes in deep elongated lakes: Evidence from Lake Garda (Italy)

Abstract

Ventilation mechanisms in deep lakes are crucial for their ecosystem functioning. In this paper we show the relevance of planetary rotation in affecting ventilation processes in relatively narrow, elongated deep lakes. Through a recent field campaign in Lake Garda (Italy), we provide explicit observational evidence for the development of lake-wide wind-driven secondary flows influenced by the Coriolis force in a narrow lake. The interpretation of these observations is supported by results from numerical simulations with a three-dimensional model of the lake. The results add an additional element, often neglected in narrow lakes, to be carefully considered when assessing the response of lakes to external forcing and climate change.