HR: 11:00h
AN: H52A-03 [Abstracts]
TI: Using High Resolution Numerical Weather Prediction Models to Reduce and Estimate Uncertainty in Flood Forecasting
AU: * Cole, S J
EM: scole@ceh.ac.uk
AF: Centre for Ecology and Hydrology, Joint Centre for Hydro-Meteorological Research,
Wallingford, Oxon, OX10 8BB, United Kingdom
AU: Moore, R J
EM: rm@ceh.ac.uk
AF: Centre for Ecology and Hydrology, Joint Centre for Hydro-Meteorological Research,
Wallingford, Oxon, OX10 8BB, United Kingdom
AU: Roberts, N
EM: nigel.roberts@metoffice.gov.uk
AF: Met Office, Joint Centre for Mesoscale Meteorology, Meteorology Building, University of
Reading, PO Box 243, Earley Gate, Reading, Berkshire, RG6 6BB, United Kingdom
AB:
Forecast rainfall from Numerical Weather Prediction (NWP) and/or nowcasting systems is a major source of
uncertainty for short-term flood forecasting. One approach for reducing and estimating this uncertainty is to use
high resolution NWP models that should provide better rainfall predictions. The potential benefit of running the
Met Office Unified Model (UM) with a grid spacing of 4 and 1 km compared to the current operational resolution of
12 km is assessed using the January 2005 Carlisle flood in northwest England. These NWP rainfall forecasts,
and forecasts from the Nimrod nowcasting system, were fed into the lumped Probability Distributed Model (PDM)
and the distributed Grid-to-Grid model to predict river flow at the outlets of two catchments important for flood
warning. The results show the benefit of increased resolution in the UM, the benefit of coupling the high-
resolution rainfall forecasts to hydrological models and the improvement in timeliness of flood warning that might
have been possible. Ongoing work aims to employ these NWP rainfall forecasts in ensemble form as part of a
procedure for estimating the uncertainty of flood forecasts.
DE: 1800 HYDROLOGY
DE: 1816 Estimation and forecasting
DE: 1847 Modeling
DE: 1873 Uncertainty assessment (3275)
SC: Hydrology [H]
MN: 2007 Fall Meeting