Abstract
The interaction between large inland water bodies and the atmosphere impacts the evolution of regional weather and climate, which in turn affects the lake dynamics, thermodynamics, ice-formation, and, therefore, ecosystems. Over the last decades, various approaches have been used to model lake thermodynamics and dynamics in standalone mode or coupled to numerical atmospheric models. We assess a turbulence-closure k-epsilon multi-column lake model in standalone mode as a computationally-efficient alternative to a full three-dimensional hydrodynamic model in the case of Lake Geneva. While it struggles to reproduce some short-term features, the multi-column model reasonably reproduces the seasonal mean of the thermal horizontal and vertical structures governing heat and mass exchanges between the lake surface and the lower atmosphere (stratified period, thermocline depth, stability of the water column). As it requires typically two orders of magnitude less computational ressources, it may allow a two-way coupling with a RCM on timescales or spatial resolutions where full 3D lake models are too demanding.
Highlights
Lakes influence the climate from the local to the synoptic scales
As it is induced by horizontal dynamics, this process cannot, by essence, be reproduced by the multi-column lake model (MCM)
While 3D hydrodynamical lake models coupled with a regional climate models (RCMs) can simulate the surface temperature distribution allowing realistic surface sensible heat and evaporation fluxes[12], their computational resource requirements prevents long-term simulations
Summary
Lakes influence the climate from the local to the synoptic scales Their effects increase with their surface area, depth, and the magnitude of seasonal changes. In order to resolve large lakes as lower boundary conditions in atmospheric numerical model in a realistic manner while limiting computing resources, a common practice consists in employing a single one-dimensional column model, or multiple independent columns taking into account the local lake bathymetry, depth, and surface forcing (e.g.4). Such an approach offers wide perspectives for applications in weather prediction and climate simulations. An intermediate option offering some insight into the horizontal and vertical thermal structure of the lake at a reasonable computing cost is desirable
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
