 |
| Titel |
Recent changes in the number of rainfall events related to debris-flow occurrence in the Chenyulan Stream Watershed, Taiwan |
| VerfasserIn |
J. C. Chen, W. S. Huang, C. D. Jan, Y. H. Yang |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1561-8633
|
| Digitales Dokument |
URL |
| Erschienen |
In: Natural Hazards and Earth System Science ; 12, no. 5 ; Nr. 12, no. 5 (2012-05-21), S.1539-1549 |
| Datensatznummer |
250010819
|
| Publikation (Nr.) |
 copernicus.org/nhess-12-1539-2012.pdf |
|
|
|
|
|
| Zusammenfassung |
| This study analyzed the variability in the number of rainfall events related
to debris-flow occurrence in the Chenyulan stream watershed located in
central Taiwan. Rainfall data between 1970 and 2009 measured at three
meteorological stations nearby/in the watershed were collected and used to
determine the corresponding regional average rainfall for the watershed.
Data on debris-flow events between 1985 and 2009 were collected and used to
study their dependence on regional average rainfall. The maximum 24-h
regional rainfall Rd was used to analyze the number of rainfall events
Nr, the number of rainfall events that triggered debris flows Nd,
and the probability of debris-flows occurrences P. The variation trends in
Nr, Nd and P
over recent decades under three rainfall conditions (Rd > 20, 230, and 580 mm) related to debris-flow occurrence were
analyzed. In addition, the influences of the Chi-Chi earthquake on Nd and P were presented. The results showed that the rainfall events with Rd > 20 mm
during the earthquake-affected period (2000–2004) strongly responded
to the increases in the average number of rainfall events that triggered
debris flows and the average probability of debris-flows occurrences. The
number of rainfall events with Rd > 230 mm (the lower boundary for the rainfall ever triggering debris
flow before the Chi-Chi earthquake), and Rd > 580 mm (the lower boundary for extreme rainfall ever triggering
numerous debris flows) in the Chenyulan stream watershed increased after
2000. The increase in the number of extreme rainfall events with Rd > 580 mm augmented the number of rainfall events ever triggering
numerous debris flows in the last decade. The increase in both the number of
rainfall events that ever triggered debris flows and the probability of
debris-flow occurrences was greater in the last decade (2000–2009) than in
1990–1999. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|