Bob
Peeters
University
of Twente
Dept. of Applied Mathematics, Faculty of EEMCS
P.O. Box 217
7500 AE Enschede
The Netherlands
Room:
CI H344
Phone: ++ 31 53 489 3415
Secretary: ++ 31 53 489 4272
Fax: ++ 31 53 489 4833
Information on my Research
and other
activities
PhD Research
Project title: "Hamiltonian-based
numerical methods for forced-dissipative climate prediction"
under supervision of Onno
Bokhove and Jason
Frank
Within
this project we try to construct new numerical schemes that aim to improve current ensemble
forecasting models for climate. Most contemporary climate models
conserve energy and potential vorticity in the case of no forcing and
dissipation. What's missing in most cases, however, is a consistent
discretization of the phase space
structure for unforced and dissipation-free flow. Constructing
such schemes is nontrivial. One may argue that this feature, in
principle, should not have an effect in the simulation of the real
climate, since it is ultimately driven by (nonuniform) solar heating
and damped by (eddy) viscosity. However, we have good reasons to
believe that such a consistent discretization, which is closer to the governing
equations in the sense that it reproduces the correct flow even if the
forcing and friction is set to zero, will lead to better climate
predictions.
Current status:
1. Towards a
Hamiltonian-based global atmospheric model
1a.
Construction of Hamiltonian discrete model for atmosphere
- Our starting point is the rotating, hydrostatic atmosphere
in absence of any forcing and friction.
- We introduce isentropic
coordinates, so that the flow becomes effectively
horizontal on each isentrope.
-
On each isentrope, we recognize dynamics akin to shallow water dynamics
but with a Montgomery potential as an Eulerian driving potential
instead of the depth field.
-
This Eulerian potential field is obtained from global information on
the temperature, and here lies the coupling
between all layers.
- Discretization follows from replacing
parcels by particles,
while for the Eulerian vertical direction we use finite elements.
1b. Implementation of the model
- We
successfully implemented the model into Matlab, using Mex files for the
main computations.
- Several analytical test solutions have been simulated.
1c. Article in progress
- "Parcel and
Particle
Hydrostatic Flow in Isentropic Coordinates"
by Bob
Peeters, Jason
Frank, and Onno
Bokhove.
1d. Outlook
- Investigate different grid smoothers.
- Gradually generalize the boundary conditions.
- Spherical model.
- Including weak forcing and friction.
2. Convergence properties of the Hamiltonian Particle-Mesh Method
2a. Article in progress
- "Optimal
Convergence of
the Hamiltonian Particle-Mesh Method: Numerical Tests"
by Vladimir Molchanov,
Bob
Peeters,
Marcel Oliver, and
Onno Bokhove.
- We are currently refining the numerical tests.
3. Low-order
model simulations
3a. Formulation of
low-order model
- We use the weak
wave model (Nore and Shepherd, 1997) as our starting
point.
- Then we apply the Zeitlin truncation to the Eulerian continuum
Poisson bracket.
- Formulation still has to be finished.
3b. Implementation of the model
- Has still to be implemented.
Seminars & conferences:
2009
- May 25-29: 2nd meeting of Wave-Flow
Interactions, a network in mathematics - Edinburgh (U.K.)
oral
presentation
2008
- Jan 7-11: Geometric and Stochastic
Methods in Geophysical Fluid Dynamics - Bremen (Germany)
oral
presentation
- April 13-18: EGU
General Assembly - Vienna (Austria)
oral
presentation
2007
-
April 15-20: EGU General Assembly - Vienna (Austria)
poster
presentation
- July 16-20: Workshop on Optimal Transportation and Applications to
Geophysics and Geometry - Edinburgh (U.K.)
oral
presentation
Links:
Numerical Analysis and
Computational Mechanics Group at Twente University, NACM
My
supervisors: Onno
Bokhove and Jason
Frank
Collaborations: Vladimir
Molchanov
Other
activities
1. Environmental
activities within the university
2. Music
3.
Hiking
& photography
Lapland 2008: Kevo Reserve (Finland)
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