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| Titel |
Space-time structure of extreme precipitation in Europe over the last century: a climate perspective. |
| VerfasserIn |
Chandra Kiran B. Krishnamurthy, Christina Karamperidou, Francesco Cioffi, Upmanu Lall |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250049350
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| Zusammenfassung |
| We analyze over a century of continuous rainfall data available from
the ECA&D archive for spatio-temporal trends in extreme precipitation.
The data base includes 515 stations with records longer than 100
years. For each station, we identify daily rainfall events in the
winter 6 months (Oct-Mar) that exceed the 99th percentile of daily
rainfall. An annual time series of the frequency of such events is
created, as well as an annual time series of the average daily
rainfall in these events. Space and time analyses of the variation of
the frequency and intensity time series are then pursued using
multivariate time and frequency domain (multi-taper method) methods.
The key trends and organized spectral modes identified are related to
potential anthropogenic change and to well established climate indices
(e.g., NAO, EAWR and SL). The simultaneous analysis of monotonic
trends over the secular period and quasi-oscillatory phenomena is
informative as to the attribution of changes in extreme precipitation
over the region. The spatial patterns associated with each
quasi-oscillatory mode and the “trend” signal are identified, and an
envelope of the time reconstruction centered at the key frequency
bands deemed significant is also identifies and related to potential
teleconnections through correlation with key atmospheric circulation
indices and SST fields. The potential implications for future risks
are discussed in the context of a Global Flood project that aims to
characterize the climate risk factors and develop instruments for
prediction and mitigation of these risks. |
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