|
|
TM is an off-line model and uses analysed meteorological
fields from the ECMWF weather forecast model to describe the
evolution of the meteorological state of the atmosphere. TM was
introduced in the Netherlands by KNMI and is further developed by a
user group at IMAU, KNMI, TUE and the Joint Research Institute of
the EU in Ispra. The TM code has in 2002/2003 been adapted for
parallel computer architectures. TM has been used in studies of
composition and transport in both the troposphere and stratosphere
and for the assimilation of stratospheric ozone The tropospheric
chemistry module is adapted from the CBM4 scheme. The treatment of
stratospheric chemistry is described in Van den Broek et al.
[2000]. A combined tropospheric and stratospheric chemistry version
is under development.
The new version of TM (TM5) [Krol et al., 2004] allows
two-way nested zooming over specific regions such as Europe. The
zooming algorithm has been coupled to the slopes advection scheme
[Russell and Lerner, 1981]. Apart from this algorithm, the second
order moments scheme [Prather, 1986] has been implemented. Non
resolved transport by deep and shallow cumulus convection has been
parameterised according to the parameterisations described by
Tiedtke [1989]. The vertical diffusion parameterisation of Holtslag
and Moeng [1991] is used for near surface mixing. In the free
troposphere, the formulation of Louis [1979] is used.
Van den Broek, M.M.P., A. Bregman and J. Lelieveld, Model
study of stratospheric chlorine activation and ozone loss during
the 1996/1997 winter, J. Geophys. Res., 105, 28,961-28,977,
2000
Holtslag, A. A. M. and Moeng, C.-H., Eddy diffusivity and
countergradient transport in the convective atmospheric boundary
layer, J. Atmos. Sci., 48, 1690-1698, 1991.
Krol, M., S. Houweling, B. Bregman, M. van den Broek, A.
Segers, P. van Velthoven, W. Peters, F. Dentener, and P.
Bergamaschi, TM5, a global two-way nested chemistry transport zoom
model: Algorithm and Applications, preprint 2004.
Tiedtke, M., A comprehensive mass flux scheme for cumulus
parametrisation in large-scale models, Mon. Wea. Rev., 177,
1779-1800, 1989.
|
