 |
| Titel |
Non-stationarity in daily and sub-daily intense rainfall – Part 2: Regional assessment for sites in south-east Australia |
| VerfasserIn |
D. Jakob, D. J. Karoly, A. Seed |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1561-8633
|
| Digitales Dokument |
URL |
| Erschienen |
In: Natural Hazards and Earth System Science ; 11, no. 8 ; Nr. 11, no. 8 (2011-08-19), S.2273-2284 |
| Datensatznummer |
250009626
|
| Publikation (Nr.) |
 copernicus.org/nhess-11-2273-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
Using data for a common period (1976–2005) for a set of 31 sites located in
south-east Australia, variations in frequency and magnitude of intense
rainfall events across durations from 6 min to 72 h were assessed. This
study was driven by a need to clarify how variations in climate might affect
intense rainfall and the potential for flooding. Sub-daily durations are of
particular interest for urban applications. Worldwide, few such
observation-based studies exist, which is mainly due to limitations in data.
Analysis of seasonality in frequency and magnitude of events revealed
considerable variation across the set of sites, implying different
dominating rainfall-producing mechanisms and/or interactions with local
topography. Both these factors are relevant when assessing the potential effects of
climate variations on intense rainfall events. The set of sites was therefore split into groups
("north cluster" and "south cluster") according to the characteristics of intense rainfall events. There is a
strong polarisation in the nature of changes found for the north cluster and south
cluster. While sites in the north cluster typically exhibit
decrease in frequency of events, particularly in autumn and at durations of
1 h and longer; sites in the south cluster experience an increase in
frequency of events, particularly for summer and sub-hourly durations.
Non-stationarity found in historical records has the potential to
significantly affect design rainfall estimates. An assessment of quantile
estimates derived using a standard regionalisation technique and periods
representative of record lengths available for practical applications show
that such estimates may not be representative of long-term conditions,
so
alternative approaches need to be considered, particularly where short
records are concerned. Additional rainfall information, in particular radar
data, could be used for an in-depth spatial analysis of intense rainfall
events. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|