Most convection schemes in operational models for numerical weather prediction
operate in a single column that is connected to other columns only via
the large scale dynamics. In particular the triggering of convection is usually
independent of the convective activity in the surrounding of the grid cell.
This is not realistic since convective activity is able to trigger
convection nearby [1,2].
Here, the intention is to work toward an implementation of nearest neighbor
interaction (NNI) within the framework of a parametrization of deep convection
within the global ICON model .
The main research question is whether a convection scheme equipped with NNI
is able to interact with the large scale dynamics in a constructive way.
In particular the focus is laid on an idealized squall line case in which the
standard convection scheme fails. It is shown how a propagating squall line can be recovered
either in the large scale dynamics, the pure NNI or the coupled dynamic.
Observations of tropical convection suggest continous phase
transition between precipitating and non-precipitating phases  similar
to what is observed in simple two-dimensional lattice models.
Thus, using simple two-dimensional presciptions to descibe horizontal correlations
in convection schemes might be suitable to introduce a scale-consistent behavior.
Percolation models are good canditates to describe spatio-temporal
correlations, critical scaling or cloud size distributions .
This motivates the current work, which investigates, how a given NNI might
interact with the dynamic of the host model and to establisch a proof of principle
that such a mechanism might be beneficial.
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: Windmiller (2017), PhD Thesis, LMU Munich, https://edoc.ub.uni-muenchen.de/21245/
How to cite: Goecke, T.: Parametrising nearest neighbor interaction in a convection scheme: an idealized squall line test case., EMS Annual Meeting 2022, Bonn, Germany, 5–9 Sep 2022, EMS2022-610, https://doi.org/10.5194/ems2022-610, 2022.