|
Titel |
Precipitation concentration changes in Spain 1946–2005 |
VerfasserIn |
M. Luis, J. C. González-Hidalgo, M. Brunetti, L. A. Longares |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1561-8633
|
Digitales Dokument |
URL |
Erschienen |
In: Natural Hazards and Earth System Science ; 11, no. 5 ; Nr. 11, no. 5 (2011-05-09), S.1259-1265 |
Datensatznummer |
250009408
|
Publikation (Nr.) |
copernicus.org/nhess-11-1259-2011.pdf |
|
|
|
Zusammenfassung |
An analysis was made of the Precipitation Concentration Index
using the new MOPREDAS database of monthly precipitation in Spain (Monthly
Precipitation Data base of Spain). The database was compiled after
exhaustive quality control of the complete digitalized Spanish Meterological
Agency (AEMet) archives and contains a total set of 2670 complete and
homogeneous monthly precipitation series from 1946 to 2005. Thus, MOPREDAS
currently holds the densest information available for the 1946–2005 period
for Spain and ensures a high resolution of results. The Precipitation
Concentration Index (PCI) is a powerful indicator of the temporal distribution
of precipitation, traditionally applied at annual scales; as the value
increases, the more concentrated the precipitation. Furthermore PCI is a part
of the well-known Fournier index, with a long tradition on natural system
analyses, as for example soil erosion. In this paper, the mean values of
annual, seasonal and wet and dry periods of PCI in the conterminous Spain
and for two normal periods (1946–1975 and 1976–2005) were studied.
Precipitation in Spain follows a general NW-SE spatial pattern during the
wet (months) period due to the Atlantic storm track, while during the dry
(months) period, it follows a predominantly N-S spatial pattern. As a result,
the annual values of PCI combine the two patterns and show a SW-NE PCI
gradient.
The analyses of the two sub-periods show significant changes in
the precipitation occurred in conterminous Spain from 1946 to 2005, and
precipitation concentration increased across most of the IP. At an annual
scale, PCI increases mostly due to an increase in precipitation
concentration during the wet season. At a seasonal scale significant changes
were detected between 1945–1975 and 1976–2005, particularly in autumn
(increase of PCI values), while changes in winter, spring and summer were
mostly localized and not generalized (both increase and decrease). Changes
in PCI seem to be complex and appear to be related to global atmospheric
features and synoptic and local factors affecting precipitation trends. We
discuss the possible explanation linked to the atmospheric pattern and monthly
trends and their implications. |
|
|
Teil von |
|
|
|
|
|
|