Abstract:
The Euler or Navier-Stokes equations for atmospheric fluid dynamics
contain motion on all length and time scales many of which are of
no or little relevance to meteorology. Explicit model reduction or
viscous turbulence parametrizations are common tools to deal with
this problem of unresolved and/or irrelevant degrees of motion.
In my talk I will survey some recent work on dispersive regularizations
for advective phenomena (alpha Euler/Navier-Stokes models) and
wave propagation (pressure regularization). These methods treat
unresolved scales by dispersive (as opposed to viscous) modifications
to the governing equations. The potential benefit of such modifications
(as opposed to viscous ones) is that the viability of the complex nonlinear
interactions between large and small scales is less reduced and more
realisticly represented within finite resolution models.
28.11.2007
13:30 h