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| Titel |
Aerodynamic resistance parameterizations in distributed hydrological models for evapotranspiration estimation |
| VerfasserIn |
Erika Ferrari, Chiara Corbari, Marco Mancini |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250145150
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| Publikation (Nr.) |
 EGU/EGU2017-9055.pdf |
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| Zusammenfassung |
| A correct evaluation of the aerodynamic resistance to heat transfer,rah, is fundamental in
several fields of application, such as sustainable water management at the basin scale and
irrigation planning at the field scale. This is due to the fact that this variable has a significant
impact on the estimation of surface heat fluxes, sensible and latent heats (H and LE), and,
consequently, of evapotranspiration (ET), which plays a key role in the hydrological cycle
and in land-atmosphere interaction.
Thus, the analysis focuses on the validation of some parameterizations for rah for
different vegetation types and surface roughness. In particular, eight equations chosen
from literature (either in accordance with the Monin-Obukhov theory or empirical,
with different assumption and levels of simplification) were compared with two
estimates of aerodynamic resistance from eddy covariance measurements (one for
momentum, ram, and one for scalars, rah) in a maize canopy, low crops and a forest.
In order to assure data quality, observations have been selected considering only
unstable conditions, where eddy covariance measurements techniques theoretical
framework is respected. The analysis has been carried out distinguishing also the
different growing phases of the vegetation, from bare soil to the maximum vegetation
height.
In accordance with the results of the validation phase, the most reliable parameterizations
have been implemented in the distributed hydrological model FEST-EWB, in order to
evaluate the effect of rah on the estimation of H and ET over different vegetation coverages. |
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