publications by Roni Avissar.
Papers Published
- Roy, S.M. and Avissar, R., Scales of response of the convective boundary layer to land-surface heterogeneity,
Geophys. Res. Lett. (USA), vol. 27 no. 4
(2000),
pp. 533 - 6 [1999GL010971] .
(last updated on 2007/03/27)Abstract:
The convective boundary layer (CBL) over domains with meso-γ-scale (2-20 km) heterogeneity is characterized by preferentially located, organized rolls of characteristic size equivalent to the length-scale of the heterogeneity. Additionally, random turbulent thermals also develop when the length-scale of the heterogeneity exceeds 5-10 km. This is due to a complex interaction between the horizontal pressure gradient generated by the heterogeneity and the buoyancy forcing. Consequently, the corresponding wavelet spectrum exhibits two peaks-one representing the turbulent thermals at a characteristic scale of about 1.5 time the CBL height and another denoting the organized eddies at a scale similar to that of the heterogeneity. This implies that subgrid-scale parameterizations in models with grid size larger than 5-10 km, which account only for random turbulence, are inadequate for heterogeneous domains. Also, this study may provide a more objective classification of scales of atmospheric processesKeywords:
atmospheric boundary layer;atmospheric movements;atmospheric turbulence;convection;




