L-GAME - bestweathermodel

The regional model L-GAME

The basic theoretical ideas behind GAME can not only be applied to global domains. Instead, also a limited-area stand-alone vesion of GAME would be desirable. In principle, it would be possible to use the hexagonal grid for this. However, the quadrilateral grid has the advantage that the parallelization and scaling behaviour is more efficient without much of the extra effort that would need to be done on the hexagonal grid. Therefore, we also develop a regional version of GAME on a quadrilateral latitude-longitude grid, called Limited-area GAME (L-GAME).

In summary, the main differences between L-GAME and GAME are the following:

Regional instead of global domain
Quadrilateral instead of hexagonal grid
A cloud scheme with five (snow, rain, ice clouds, water clouds, graupel) instead of four constituents (snow, rain, ice clouds, water clouds)

Sample plots

Schär test

The Schär testexamines a model's ability to accurately simulate gravity waves produced by a mountain ridge perpendicular to a given background flow. Its advantage is that an analytical solution is known to which the model output can be compared.

Schaer test vertical velocity — Vertical velocity in the Schär test after five hours of simulation time. The test setup is defined by N = 0.01/s and U = 10 m/s. The horizontal and vertical mesh sizes are 500 m and 300 m, respectively. Contour lines reach from -0.5 to 0.5 m/s with a distance of 0.05 m/s, excluding zero.

The results agree well to those of other models.

Nesting options

L-GAME can currently be nested into the following models:

Into ICON down to a resolution of 2.5 km (medium-sized domains worldwide)
Into ICON-EU down to a resolution of 1.4 km (medium-sized domains within Europe and surrounding areas)
Into ICON-D2 down to a resolution of 500 m (small domains within Germany and surrounding areas)

Such implementations can be set up on-demand, meaning within one hour.