The Probability-Distributed Model, or PDM, is a general conceptual rainfall-runoff model which transforms time-series of rainfall and evaporation to river flow at the catchment outlet (Moore, 1985, 1999, 2007).
The model formulation is based on a probability-distributed moisture store and translation of runoff and drainage via routing stores.
The PDM is used for operational flood forecasting across the UK and abroad. It has been applied to a wide range of hydrological studies including climate change impact (e.g. Kay & Jones (2012), Kay et al. (2020)), water resource management (e.g. eFLaG) and modelling ungauged locations (e.g. Kay et al. (2007)).
Methodological developments include enhanced groundwater representation (Moore & Bell, 2002), inter-catchment water exchange and multi-zone functionality for modelling mixed urban/rural catchment responses and higher/lower rainfall areas.
The PDM software is available under licence in two forms:
- PDM for PCs. A Windows-based application for interactive model calibration and assessment.
- UKCEH XML Module Adapter. An executable module for use in operational flood forecasting systems (e.g. Delft-FEWS) and for batch processing on Windows and Linux systems.
The PDM software has the following features:
- model toolkit to represent a variety of catchments
- choice of time-step, such as 15 minutes and daily
- choice of instantaneous or accumulated flows
- forecasts created using state-updating or error-prediction methods
- comprehensive manual
In addition, the PDM for PCs calibration application has the following functionality:
- automatic and interactive calibration facilities
- graphical user-interface
- output to Excel and other graphical tools
- automated event selection
- performance assessment of threshold-crossings and flood peaks
- wide range of statistical analyses
Contact for further information
For further information on PDM, please contact Bob Moore via the ForecastModelSupport@ceh.ac.uk email.
UK Centre for Ecology & Hydrology
Telephone: +44(0)1491 692262
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