Castle Ludwigslust
Ludwigslust Palace

About MagicLake

This historical animation of 1993 shows the temperature dynamics of a quasi 1D water-column numerical model actually developed for lakes. It contains wind- and inflow-driven horizontal currents, turbulent kinetic energy and her dissipation rate, turbulent vorticity, temperature, and eddy viscosity. In addition to these standard variables of ocean water-column models the code also describes wind-driven internal seiches. These are important in lakes as the associated counter flows at the bottom may bring toxic or anoxic sediments into suspension or even into solution. In the present animation we took the North Sea as a big lake so that the internal seiches did not matter. The reason we took this case was the need of a model-observation comparison. We selected the unique FLEX’76 data set gained through the third phase of JONSDAP’76 with the research vessels Meteor and Anton Dohrn und supervision of Klaus Hasselmann. This data is unique as it not only contains vertical profiles in high space-time density over a longer time but also the meteorological forcing of the water column by winds etc. The animation shows nicely the action of storms and calm situations on the water column evolution. The code has been developed together with Gisbert Stoyan in Budapest and Barnabas Szilagyi in New York. It allows the animation of three variables:

Water temperature: T = T(z, t) given in degrees Celsius
Vertical eddy diffusivity: v = v(z, t) given in m² s¯¹
Horizontal velocities: U = U(z,t), V = V(z, t) given in m s¯¹

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