Abstract
Abstract. Mesoscale convective systems (MCSs) are especially visible in the summertime when there is an advection of warm maritime air from the west. Advection of air masses is enriched by water vapour, the source of which can be found over the Mediterranean Sea. In propitious atmospheric conditions, and thus significant convection, atmospheric instability or strong vertical thermal gradient leads to the development of strong thunderstorm systems. In this paper, we discuss one case of MCSs, which generated a significant amount of +CG (cloud-to-ground), −CG and intracloud (IC) discharges. We have focused on the ELF (extremely low frequency; < 1 kHz) electromagnetic field measurements, since they allow us to compute the charge moments of atmospheric discharges. Identification of the MCSs is a complex process, due to many variables which have to be taken into account. For our research, we took into consideration a few tools, such as cloud reflectivity, atmospheric soundings and data provided by PERUN (Polish system of the discharge localisation system), which operates in a very high frequency (VHF) range (113.5–114.5 MHz). Combining the above-described measurement systems and tools, we identified a MCS which occurred in Poland on 23 July 2009. Furthermore, it fulfilled our requirements since the thunderstorm crossed the path of the DEMETER (Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions) overpass.
Highlights
Mesoscale convective systems (MCSs) are enormous cloud structures known as one of the strongest discharge generators in the world (Bonner, 1968; Banta et al, 2002; Houze, 2014)
It fulfilled our requirements since the thunderstorm crossed the path of the DEMETER (Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions) overpass
We focused on a specific type of thunderstorm, an MCS classified as a derecho, which is not frequent in Europe and may be disastrous for overpassed areas
Summary
Mesoscale convective systems (MCSs) are enormous cloud structures known as one of the strongest discharge generators in the world (Bonner, 1968; Banta et al, 2002; Houze, 2014). We have designated one event of the MCS which occurred on 23 July 2009. The selection of this specific MCS was not random; we have been looking for the most favourable conditions to conduct the research and, significant convection, atmospheric instability or strong vertical thermal gradient. Since we focused on Poland, we had access to data provided by the Polish meteorological service, IMGW–PIB (Institute of Meteorology and Water Management – National Research Institute). TER overpasses in order to distinguish periods in which it was over Poland
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
