CReSS: A Cloud Resolving Storm Simulator

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CReSS A Cloud Resolving Storm Simulator

• Simulation of a Tornado within a Supercell

CReSS is a cloud resolving atmospheric model
designed for a high performance parallel
computing to simulate cloud-scale to storm-scale
phenomena. Objectives of CReSS are thunder-storms
and related phenomena tornadoes, downbursts,
hail storms, squall lines and so on.
CReSS performed a simulation experiment of a
tornado within a supercell observed on 24
September 1999 in the Tokai District of Japan.
The simulation aimed to resolve the vortex of the
tornado and its parent supercell with a
uniformly-spaced grid system.

• Key Features of CReSS

Horizontal display of the simulated supercell is
shown with a closed-up horizontal (up-right) and
vertical (down-left) cross-section of the
simulated tornado. The computational domain is
approximately 50 x 50 km in horizontal and the
grid-spacing is 100 m. The result shows CReSS
can successfully simulate tornado and supercell.

• The three-dimensional non-hydrostatic and
  compressible equation system in a
  terrain-following coordinate
• The 1.5th order turbulent closure
• Warm and cold rain bulk parameterizations
• A parallel computation in use of MPI

The tornado hit Toyohashi city, mid-Japan on 24
September 1999.
Two dimensional domain decomposition and
communication strategy.