A logically Cartesian, adaptively refined two-patch sphere grid for modeling transport in the atmosphere
Seminar Room 1, Newton Institute
Recently, we demonstrated results using a second order
finite volume scheme on a novel, logically Cartesian, two-patch 2d
sphere grid. The numerical scheme, based on the wave-propagation
algorithms in Clawpack ( R. J. LeVeque, Univ. of Washington), was
easily adapted to the single grid Cartesian layout of our two-patch
sphere grid mapping. Furthermore, we were able to use an existing
adaptive mesh refinement patch-based (AMR) code (Berger, Oliger et
al.) to run computational efficient simulations.
In our current work, we are developing a new AMR code which uses wave
propagation algorithms on non-overlapping AMR grids stored as leaves
in a forest of quad- or oct-trees. The underlying tree-based code,
p4est (Carsten Burstedde, Univ. of Bonn) manages the multi-block
connectivity in a multi-processor environment and has been shown to be
highly scalable in applications of interest to geophysicists. This
new AMR code, which we call ForestClaw, will easily handle the
adaptivity for our two-patch sphere grid, as well as the cubed-sphere,
and more generally, any multi-block geometry.
We will present preliminary results from our efforts to use ForestClaw
for modeling volcanic ash dispersal in the atmosphere. This is joint
work with Carsten Burstedde (Univ. of Bonn) and researchers at the
Cascade Volcanic Observatory (Vancouver, Washington).