Journal : Acta Geophysica
Article : Assessment of the hydraulic slope flow approach using a mesoscale model

Authors :
Shapiro, A.
School of Meteorology, University of Oklahoma, Norman, Oklahoma, USA, ashapiro@ou.edu,
Axelsen, S. L.
IMAU, Utrecht University, Utrecht, The Netherlands, s.l.axelsen@uu.nl,
Axelsen, S. L.
IMAU, Utrecht University, Utrecht, The Netherlands, s.l.axelsen@uu.nl,
Steeneveld, G. J.
Department of Meteorology and Air Quality,Wageningen University, Wageningen, The Netherlands, gert-jan.steeneveld@wur.nl,
Martínez, D.
Departament de Física, Universitat de les Illes Balears, Mallorca, Spain, dani.martinez@uib.cat,
Abstract : The simplified hydraulic two-layer model for a katabatic flow is analysed using the outputs from a high-resolution mesoscale simulation. A stably stratified night is simulated for the Duero basin, a complex terrain area located in the northern Spanish plateau, with large vertical and horizontal spatial resolution. Well-defined katabatic flows on the basin slopes are generated by the simulation, that are relatively stationary and quasi-bidimensional for some areas in the central part of the night. The bulk quantities used in the two-layer approach as well as the different terms in the equations are computed from the three-dimensional information provided by the mesoscale simulation. This method allows to inspect how well the simplified approach represents the katabatic flow generated by the mesoscale model. The study shows that the hydraulic model allows for a comprehensive analysis of the basic mechanisms of the slope flows but is not able to close the budget equations, since the residuals are large.

Keywords : katabatic flows, Duero basin, mesoscale modelling, hydraulic two-layer model, stable boundary layer,
Publishing house : Instytut Geofizyki PAN
Publication date : 2009
Number : Vol. 57, no. 4
Page : 882 – 903

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DOI :
Qute : Shapiro, A. ,Axelsen, S. L. ,Axelsen, S. L. ,Steeneveld, G. J. ,Martínez, D. ,Martínez, D. , Assessment of the hydraulic slope flow approach using a mesoscale model. Acta Geophysica Vol. 57, no. 4/2009
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