A re-examination of the seiche periods of Lake Vättern

Abstract

A newly developed perturbation technique for resolving Chrystal's classical seiche problem has been applied to Vättern, a deep and elongated lake in central Sweden. Theoretical predictions of the standing-wave periods were compared to those obtained from spectral analysis of a 3-month water level record. The results for the gravest-mode seiche were found to be in good agreement, whereas the second- and third-mode predictions showed a systematic deviation from the observations. A sensitivity analysis of the computational procedure indicates that this discrepancy can most likely be ascribed to insufficient knowledge of the detailed topography of the lake.