We analyzed season-long water level records at 12 stations around the Lake of Geneva (local name Léman) for evidence of internal seiches modified by Coriolis force and compared the results with predictions from a two-layer numerical model with real bottom topography for typical wind situations. Results are also compared with those obtained from current and temperature measurements in the lake. Agreement was satisfactory in all cases. Model predictions and measurements both indicated that only three internal seiche modes are excited: the 1st mode and the 3rd mode, which are Kelvin-seiche oscillations, and the 12th mode, which is a Poincaré seiche. The model, driven by winds from different directions, demonstrates that the wind field, constrained by the local topography, determines which of the modes is generated.

Observations in the littoral zone of a large lake (Lake Constance) revealed strong and periodic fluctuations of temperature and current velocity on timescales between 10 and 15 min associated with high‐frequency internal waves. The peak in the spectral energy of the current velocity fluctuations associated with high‐frequency internal waves follows the seasonal dynamics of stratification, described by the stability frequency N. A comparison between the nearshore current velocity measurements in the littoral zone with temperature measurements in the pelagic of Lake Constance revealed a strong coupling between the occurrence of high‐frequency internal waves in the littoral zone and the passage of the basin‐scale internal Kelvin wave with a period of about 4 d.

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We present results of various circulation scenarios for the wind-induced three-dimensional currents in Lake Constance, obtained with the aid of a semi-spectral semi-implicit ®nite dierence code developed in Haidvogel et al. and Wang and Hutter. Internal Kelvin and PoincareÂ-type oscillations are demonstrated in the numerical results, whose periods depend upon the strati®cation and the geometry of the basin and agree well with measured data. By solving the eigenvalue problem of the linearized shallow water equations in the two-layered strati®ed Lake Constance, the interpretation of the oscillations as Kelvin and PoincareÂ-type waves is corroborated.

Abstract. We present results of various circulation scenarios for the wind-induced three-dimensional currents in Lake Constance, obtained with the aid of a semi-spectral semi-implicit ®nite dierence code developed in Haidvogel et al. and Wang and Hutter. Internal Kelvin and Poincare -type oscillations are demonstrated in the numerical results, whose periods depend upon the strati®cation and the geometry of the basin and agree well with measured data. By solving the eigenvalue problem of the linearized shallow water equations in the two-layered strati®ed Lake Constance, the interpretation of the oscillations as Kelvin and Poincare -type waves is corroborated.