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| Titel |
Characterisation of Convective Regimes over the British Isles |
| VerfasserIn |
David Flack, Robert Plant, Suzanne Gray, Humphrey Lean, Christian Keil, George Craig |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250123087
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| Publikation (Nr.) |
 EGU/EGU2016-2278.pdf |
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| Zusammenfassung |
| Convection-permitting modelling has led to a step change in forecasting convective events.
However, convection occurs within different regimes which exhibit different forecast
behaviour. A convective adjustment timescale can be used to distinguish between these
regimes and examine their associated predictability. The convective adjustment timescale is
examined for three summers in the British Isles to determine characteristics of the convective
regimes for this maritime region. Convection in the British Isles is predominantly in
convective quasi-equilibrium with 85% of convection occurring in this regime. This
percentage varies spatially with more non-equilibrium events occurring in the south and
southwest. The non-equilibrium regime occurs more frequently when windspeeds are
between 5 and 15 ms−1and from the southerly to westerly sectors. The convective
adjustment timescale is longest when the location being examined is downstream
of large orographic gradients; and decreases with distance from the convective
initiation region. Most non-equilibrium convective events in the British Isles are
initiated near large coastal orographic gradients or on the European continent. The
dominance of convective quasi-equilibrium conditions over the British Isles argues
for the use of large-member ensembles in probabilistic forecasts for this region. |
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