|
Titel |
Evaluation of evapotranspiration methods for model validation in a semi-arid watershed in northern China |
VerfasserIn |
K. Schneider, B. Ketzer, L. Breuer, K. B. Vaché, C. Bernhofer, H.-G. Frede |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1680-7340
|
Digitales Dokument |
URL |
Erschienen |
In: Large-scale hydrological modelling and the European Union water policies ; Nr. 11 (2007-05-30), S.37-42 |
Datensatznummer |
250009006
|
Publikation (Nr.) |
copernicus.org/adgeo-11-37-2007.pdf |
|
|
|
Zusammenfassung |
This study evaluates the performance of four evapotranspiration methods
(Priestley-Taylor, Penman-Monteith, Hargreaves and Makkink) of differing
complexity in a semi-arid environment in north China. The results are
compared to observed water vapour fluxes derived from eddy flux
measurements. The analysis became necessary after discharge simulations
using an automatically calibrated version of the Soil and Water Assessment
Tool (SWAT) failed to reproduce runoff measurements. Although the study area
receives most of the annual rainfall during the vegetation period, high
temperatures can cause water scarcity. We investigate which
evapotranspiration method is most suitable for this environment and whether
the model performance of SWAT can be improved with the most adequate
evapotranspiration method.
The evapotranspiration models were tested in two consecutive years with
different rainfall amounts. In general, the simple Hargreaves and Makkink
equations outmatch the more complex Priestley-Taylor and Penman-Monteith
methods, although their performance depended on water availability. Effects
on the quality of SWAT runoff simulations, however, remained minor. Although
evapotranspiration is an important process in the hydrology of this steppe
environment, our analysis indicates that other driving factors still need to
be identified to improve SWAT simulations. |
|
|
Teil von |
|
|
|
|
|
|