 |
| Titel |
Long term variability of the annual hydrological regime and sensitivity to temperature phase shifts in Saxony/Germany |
| VerfasserIn |
M. Renner, C. Bernhofer |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 15, no. 6 ; Nr. 15, no. 6 (2011-06-16), S.1819-1833 |
| Datensatznummer |
250012853
|
| Publikation (Nr.) |
 copernicus.org/hess-15-1819-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
Recently, climatological studies report observational evidence of changes in
the timing of the seasons, such as earlier timing of the annual cycle of
surface temperature, earlier snow melt and earlier onset of the phenological
spring season. Also hydrological studies report earlier timing and changes in
monthly streamflows. From a water resources management perspective, there is
a need to quantitatively describe the variability in the timing of
hydrological regimes and to understand how climatic changes control the
seasonal water budget of river basins.
Here, the timing of hydrological regimes from 1930–2009 was investigated in
a network of 27 river gauges in Saxony/Germany through a timing measure
derived by harmonic function approximation of annual periods of runoff ratio
series. The timing measure proofed to be robust and equally applicable to
both mainly pluvial river basins and snow melt dominated regimes.
We found that the timing of runoff ratio is highly variable, but markedly
coherent across the basins analysed. Differences in average timing are
largely explained by basin elevation. Also the magnitude of low frequent
changes in the seasonal timing of streamflow and the sensitivity to the
changes in the timing of temperature increase with basin elevation. This
sensitivity is in turn related to snow storage and release, whereby snow
cover dynamics in late winter explain a large part of the low- and
high-frequency variability.
A trend analysis based on cumulative anomalies revealed a common structural
break around the year 1988. While the timing of temperature shifted earlier
by 4 days, accompanied by a temperature increase of 1 K, the timing of
runoff ratio within higher basins shifted towards occurring earlier about 1
to 3 weeks. This accelerated and distinct change indicates, that impacts of
climate change on the water cycle may be strongest in higher, snow melt
dominated basins. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|