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| Titel |
Characteristics of radar-derived hailstreaks across Central Europe |
| VerfasserIn |
Michael Kunz, Elody Fluck, Manuel Schmidberger, Heinz Jürgen Punge, Sven Baumstark |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250151003
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| Publikation (Nr.) |
 EGU/EGU2017-15541.pdf |
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| Zusammenfassung |
| Hailstorms are among the most damaging natural disasters in various parts of Europe. For
example, two supercells in Germany, on 27 and 28 July 2013, bearing hailstones with a
diameter of up to 10 cm, caused economic losses of around 4.0 billion EUR. Despite the
large damage potential of severe hailstorms, knowledge about the probability and severity of
hail events and hailstorm-favoring conditions in Europe still is limited.
A large event set of past severe thunderstorms that occurred between 2004 and 2014 was
identified for Germany, France, Belgium, and Luxembourg from radar data considering a
lower threshold of 55 dBZ of the maximum Constant Altitude Plan Position Indicator
(maxCAPPI). Additional filtering with lightning data and applying a cell tracking algorithm
improves the reliability of the detected severe thunderstorm tracks. The obtained
statistics show a gradual increase of the track density with increasing distance to the
Atlantic and several local-scale maxima, mostly around the mountains. Both the
seasonal and daily cycle of severe thunderstorms show large differences across
the investigation area. For example, while in Southern France most events occur
in June, the peak month in Northern Germany is August, which can be plausibly
explained by differences in convective energy due to the large-scale circulation.
Furthermore, ambient conditions in terms of convection-related quantities (e.g., CAPE,
wind shear, lapse rate) and prevailing synoptic scale fronts were studied both for
the entire event set and a subset, where radar-derived storm tracks were combined
with hail observations provided by the European Severe Weather Database ESWD.
Over Northern Germany, for example, up to 40% of all radar-derived thunderstorm
tracks were associated with cold fronts, while in Southern Germany the ratio is only
around 20%. Overall, around 25% of all hail streaks were associated with cold
fronts. |
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