CLOUD ELECTRIFICATION MODEL IN THE COSMO NUMERICAL WEATHER PREDICTION MODEL

0497596 - ÚFA 2019 NL eng A - Abstract
Sokol, Zbyněk - Minářová, Jana
CLOUD ELECTRIFICATION MODEL IN THE COSMO NUMERICAL WEATHER PREDICTION MODEL.
10th European Conference on Radar in Meteorology and Hydrology (ERAD 2018). Ede-Wageningen: Wageningen University & Research, 2018 - (Vos, L.; Leijnse, H.; Uijlenhoet, R.). s. 89
[European Conference on Radar in Meteorology and Hydrology (ERAD 2018) /10./. 01.07.2018-06.07.2018, Ede-Wageningen]
Institutional support: RVO:68378289
Keywords : Cloud Electrification Model (CEM) * numerical weather prediction model * cloud microphysics
OECD category: Meteorology and atmospheric sciences
http://library.wur.nl/WebQuery/wurpubs/539463

In this contribution, we implemented the Cloud Electrification Model (CEM) in
the COSMO non-hydrostatic numerical weather prediction model. CEM computes
with 2-moment cloud microphysics and consists of both the inductive and noninductive
charging mechanisms with the last the dominant. CEM explicitly describes
the concentration of ions and the ion interaction with six kinds of hydrometeors to
which the concentration of charge is bounded.
CEM models the advection of charges bounded to hydrometeors, changes in
charge concentration in cloud microphysical scheme, ion equation, separation and
transfer of charge related to collisions of hydrometeors, and lightning. Lightning
scheme is based on bidirectional concept of the flash leader and the propagation of
the flash is given by probabilistic branching (dielectric breakdown concept).
The results of simulations show that CEM enables to capture the typical thundercloud
tripole charge structure with two positive layers separated by a negative layer.
The negative layer is related to high concentration of graupel, ice and snow hydrometeors
which are the hydrometeors the most participating in the charge transfer due
to their collisions. In more detail, CEM also simulates the charge distributed following
the updrafting and downdrafting motion, similar to that given in literature.
Permanent Link: http://hdl.handle.net/11104/0290142