WTD 2015: Internationale wissenschaftliche Veranstaltung: "7th Warnemünde Turbulence Days (WTD) 2015 on "Energy and matter fluxes mediated by marine and atmospheric turbulence"", Putbus, 30.08.15-03.09.15
The WTD workshops are devoted to the observation, interpretation, and modelling of oceanic turbulence and its interaction with physical and ecosystem parameters. Workshops in this series are held on a biannual basis, and are characterised by their active working atmosphere with a relatively small number of invited speakers, and a comfortable time frame for presentations and discussion. In 2015, the WTD will be held again on the beautiful island of Vilm, a nature reserve in the Western Baltic Sea.
In geophysical fluid dynamics, energy and matter fluxes are largely determined by turbulence. Mathematically, these fluxes are defined as the covariance between the velocity vector and the matter concentration or temperature. In the ocean and the atmosphere, eddy covariance methods have been successfully applied to directly measure theses fluxes. In numerical models, parameterisations based on the down-gradient assumption are generally used, relying on eddy diffusivity as key parameter. Sediment-water and air-sea fluxes directly depend on boundary layer properties such as shear stresses and turbulent fluctuations. Particulate suspended matter in the ocean (or aerosols in the atmosphere) may aggregate or disaggregate depending on the level of small-scale turbulence, a process which additionally influences their fluxes. At larger scales, the lateral transports of matter and energy are mediated by geostrophic and ageostrophic eddies. Poleward heat transport in the Southern Ocean is an important example for this process, where the eddy diffusivity assumption generally breaks down, and various suggestions for non-local parameterisations have been made. In between the small-scale fluxes and the large scale eddy transports, also internal waves significantly contribute to matter and energy fluxes. Interactions between these three regimes are barely understood, and in models of the ocean and the atmosphere parameterisations often violate basic conservation laws, massively reducing their predictive power.
It is the aim of the 7th Warnemünde Turbulence Days to elucidate the scientific challenges of "Energy and matter fluxes mediated by marine and atmospheric turbulence" and to discuss new related concepts on a large spectrum of scales in oceanography, limnology, and atmospheric sciences.