Strong bottom currents in large, deep Lake Geneva generated by higher vertical-mode Poincare waves.

ABSTRACT: Although internal seiches are ubiquitous in large, deep lakes, little is known about the effect of higher vertical-mode seiches on deepwater dynamics. Here, by combining entire summer season current and temperature observations and 3D numerical modeling, we demonstrate that previously undetected vertical mode-two and mode-three Poincaré waves in 309-meter deep Lake Geneva (Switzerland/France) generate bottom-boundary layer currents up to 4 cm s-1. Poincaré wave amphidromic patterns revealed three strong cells excited simultaneously. Weak hypolimnetic stratification (N2 ≈ 10-6s-2), typical of deep lakes, significantly modified the wave structure by shifting the lower vertical node in the lake's center from ~75-meter depth (without stratification) to ~150-meter depth (with stratification). T

SUBMITTER: Reiss RS 

PROVIDER: S-EPMC11371635 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature