The TRR 181 seminar is held by Dr. Knut Klingbeil (Universität Hamburg/IOW, Subproject M5) on
"Numerical Mixing - Sources, Quantification and Reduction"
at Universität Hamburg, on January 19 at 10 am, Bundesstr. 53, Room 24 (ground floor).
The development towards energy-consistent models requires both, advanced parameterisations of unresolved processes and an improved numerical treatment of resolved processes. For the latter, especially the advective transport relative to the model grid needs to be discretised with sufficient accuracy to minimise spurious numerical mixing (causing an unphysical transfer between available and background potential energy) and spurious numerical dissipation of kinetic energy (caused by the advection of momentum).
A reliable diagnostic tool is central to quantify numerical mixing and to assess new model techniques, designed to reduce numerical mixing. In this talk a recently developed analysis method will be presented, that offers the quantification of numerical mixing in each grid cell and thus the identification of critical regions in the model domain. Based on exemplary hotspots of numerical mixing, several approaches for new model techniques (to be investigated in subproject M5) will be outlined.