Open AccessBasin‐scale internal wave dynamics during a winter cooling period in a large lake
Author(s) -
Rueda Francisco J.,
Schladow S. Geoffrey,
Pálmarsson Sveinn Ó.
Publication year - 2003
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2001jc000942
Subject(s) - geology , internal wave , stratification (seeds) , storm , kelvin wave , structural basin , dissipation , geophysics , climatology , atmospheric sciences , physics , geomorphology , oceanography , seed dormancy , botany , germination , dormancy , biology , thermodynamics
Basin‐scale internal waves are examined using a combined field observation and 3‐D numerical approach. The field site, Lake Tahoe (CA‐NV) during winter, is characterized by the presence of a weak density stratification and the passage of several storm fronts of varying character. Under these conditions internal waves with periods greater than 5 days and displacements of 30 m are possible. The model used is shown to have negligible numerical dissipation and sufficiently small phase lag over the time periods needed to represent basin‐scale waves. Both the numerical results and the observations identify the presence of three Kelvin modes and one Poincaré mode. While the wave periods are consistent with theoretical predictions, the spatial characteristics are far more complex than theory can predict. The spatial features are revealed through analysis of the integrated potential and kinetic energy fields yielded by the model. This shows that the basin topography exerts an influence on both Kelvin and Poincaré waves. The effect of the variable storms and, in particular, the phasing of the storms with respect to the internal waves is shown to be responsible for the amplification and annihilation of the basin‐scale waves.