HESS Hydrology and Earth System Sciences HESS Hydrol. Earth Syst. Sci. 1607-7938 Copernicus Publications Göttingen, Germany 10.5194/hess-4-419-2000 Physical disaggregation of numerical model rainfall Fox N. I. 1 2 Collier Ch. G. 1 Telford Institute of Environmental Systems, School of Environment and Life Sciences, Peel Building, University of Salford, Salford M5 4WT e-mail for corresponding author: n.i.fox@salford.ac.uk 30 09 2000 4 3 419 424 Copyright: © 2000 N. I. Fox 2000 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://hess.copernicus.org/articles/4/419/2000/hess-4-419-2000.html The full text article is available as a PDF file from https://hess.copernicus.org/articles/4/419/2000/hess-4-419-2000.pdf

A methodology is presented for the disaggregation of numerical model fields of convective rainfall using a physically based procedure. The scheme uses surface sensible heat flux values derived from high-resolution multichannel satellite radiometer observations. The sensible heat flux values initialise a simple convective model to calculate the convective disaggregation parameter (CDP), which is theoretically proportional to the convective rainfall rate. The CDP diagnostic parameter can be derived as a one-time field if the surface characteristics are invariant, as a seasonal value may be, or it may be evaluated on a case by case basis. Once found, the CDP can be used to disaggregate numerical weather prediction (NWP) convective rainfall fields for as far ahead as such fields are produced.