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| Titel |
The temporal evolution of three-dimensional lightning parameters and their suitability for thunderstorm tracking and nowcasting |
| VerfasserIn |
V. K. Meyer, H. Höller, H. D. Betz |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 10 ; Nr. 13, no. 10 (2013-05-22), S.5151-5161 |
| Datensatznummer |
250018662
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| Publikation (Nr.) |
 copernicus.org/acp-13-5151-2013.pdf |
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| Zusammenfassung |
| Total lightning (TL) data have been found to provide valuable information
about the internal dynamics of a thunderstorm allowing
conclusions about its further development as well as indicating potential
of thunderstorm-related severe weather at the
ground. This paper investigates electrical discharge correlations of strokes and
flashes with respect to the temporal evolution
of thunderstorms in case studies as well as by statistical means. The recently
developed algorithm li-TRAM (tracking and monitoring of lightning cells,
Meyer et al., 2013) has been employed to track and monitor
thunderstorms based on three-dimensionally
resolved TL data provided as stroke events by the European lightning
location network LINET. From statistical investigation of
863 suited thunderstorm life cycles, the cell area turned out
to correlate well with (a) the total discharge
rate, (b) the in-cloud (IC) discharge rate, and (c) the mean IC discharge height
per lightning cell as identified by
li-TRAM. All three parameter correlations consistently show an abrupt change in
discharge characteristics around a cell area of
170 km2. Statistical investigations supported by the comparison of
three case studies – selected to represent
a single storm, a multi-cell and a supercell – strongly suggest that the
correlation functions include the temporal evolution
as well as the storm type. With the help of volumetric radar data, it can
also be suggested that the well-defined break
observed at 170 km2 marks the region where the transition occurs
from short-lived and rather simple structured
single storm cells to better organized, more persistent, and more complex
structured thunderstorm forms, e.g. multi-cells and
supercells. All three storm types experience similar discharge characteristics
during their growing and dissipating
phases. However, while the poorly organized and short-lived cells preferentially
remain small during a short mature phase,
mainly the more persistent thunderstorm types develop to sizes above
170 km2 during a pronounced mature stage. At
that stage they exhibit on average higher discharge rates at higher altitudes as
compared with matured single cells. With the
maximum stroke distance set to 10 km and a flash duration set to
1 s, the parameterization functions found
for the stroke rate as a function of the cell area have been transformed to a flash
rate. The presented study suggests that, with
respect to the storm type, stroke and flash correlations can be parameterized.
There is also strong evidence that
parameterization functions include the time parameter, so that altogether TL
stroke information has good potential to pre-estimate the further evolution (nowcast) of a currently observed storm in
an object-oriented thunderstorm nowcasting approach. |
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