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| Titel |
Scale-wise evolution of rainfall probability density functions fingerprints the rainfall generation mechanism |
| VerfasserIn |
Annalisa Molini, Gabriel Katul, Amilcare Porporato |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250043847
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| Zusammenfassung |
| Possible linkages between climatic fluctuations in rainfall at low frequencies and local
intensity fluctuations within single storms is now receiving significant attention in climate
change research. To progress on a narrower scope of this problem, the cross-scale
probabilistic structure of rainfall intensity records collected over time scales ranging from
hours to decades at sites dominated by either convective or frontal systems is investigated.
Across these sites, intermittency buildup from slow to fast time-scales is analyzed in terms of
its heavy tailed and asymmetric signatures in the scale-wise evolution of rainfall probability
density functions (pdfs). The analysis demonstrates that rainfall records dominated by
convective storms develop heavier-tailed power law pdfs across finer scales when compared
with their frontal systems counterpart. A concomitant marked asymmetry buildup
also emerges across finer time scales necessitating skewed probability laws for
quantifying the scale-wise evolution of rainfall pdfs. A scale-dependent probabilistic
description of such fat tails, peakedness and asymmetry appearance is proposed
and tested by using a modified q-Gaussian model, able to describe the scale wise
evolution of rainfall pdfs in terms of the nonextensivity parameter q, a lacunarity
(intermittency) correction γ and a tail asymmetry coefficient c, also functions of q. |
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