Research cloud electrification model in the Wisconsin dynamic/microphysical model 2: Charge structure in an idealized thunderstorm and its dependence on ion generation rate

0554079 - ÚFA 2023 RIV NL eng J - Journal Article
Popová, Jana - Sokol, Zbyněk - Šlegl, Jakub - Wang, P. - Chou, Y.-L.
Research cloud electrification model in the Wisconsin dynamic/microphysical model 2: Charge structure in an idealized thunderstorm and its dependence on ion generation rate.
Atmospheric Research. Roč. 270, June 1 (2022), č. článku 106090. ISSN 0169-8095. E-ISSN 1873-2895
R&D Projects: GA MŠMT EF15_003/0000481
Grant - others:AV ČR(CZ) StrategieAV21/20; AV ČR(CZ) MOST-20-04
Program: StrategieAV; Bilaterální spolupráce
Institutional support: RVO:68378289 ; RVO:61389005
Keywords : Cloud electrification model * Cloud model * Cloud microphysics * Cosmic ray
OECD category: Meteorology and atmospheric sciences; Meteorology and atmospheric sciences (UJF-V)
Impact factor: 5.5, year: 2022
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S016980952200076X?via%3Dihub

This paper presents a cloud electrification model, which we embedded in the Wisconsin Dynamic and Microphysical Model-2 and labels it CEMW. WISDYMM-2 makes use of two-moment cloud microphysics to produce 5 hydrometeor types (e.g., cloud-droplets, raindrops, cloud-ice, snow, and graupel) that are used by CEMW for storm electrification where storm convection is initiated by a warm air bubble that is placed over an assumed flat terrain with no surface friction. In this paper, CEMW was used to examine cloud electrification in a simulated (idealized) thundercloud and to examine the impact of various formulations of the ion generation rate by cosmic rays (G) on how the storm and individual hydrometeor charges were structured. Results showed that the CEMW generates reasonable electric charge structures, which is qualitatively similar to those published by Brothers et al. (2018) in that it consists of a number of smaller positively and negatively charged regions. This structure differs from a charge structure generally depicted by conceptual models based on conventional balloon measurements of electric field. However, simulated balloon measurements in the idealized thunder clouds further revealed that CEMW produces electrostatic charge distributions and electric field profiles that are in good agreement with those reported by real balloon measurements. How charge is structured by CEMW was tested by formulating G (the ion generation rate) in two different ways. First, we derived G assuming fair weather conditions, which is the usual way applied in cloud electrification modelling. Second, we calculated Gs using the Cosmic Ray Atmospheric Cascade: Cosmic Ray Induced Ionization model for several values of solar modulation potential and cut-off rigidity. The results show that the structure of the electric charge fields does not differ much depending on G, but the fundamental difference between G is in the amount of electric discharges.
Permanent Link: http://hdl.handle.net/11104/0328717