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Explore the MOGREPS ensemble system for 15-day tropical cyclone forecasts, case studies, verification results, and global/regional components. Learn about the use of these products and upcoming developments in TC tracking.
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Ensemble Forecasting Products for Tropical Cyclones at the UK Met Office. Piers Buchanan and Ken Mylne, Ensemble Forecast Applications, UK Met Office
Overview 1 The MOGREPS ensemble system 2 Tropical cyclones 15 day ensemble forecast products 3 Two case studies 4 Use of these products at the Met Office (and beyond) 5 Some objective verification results
Global Component (MOGREPS-G) 60km, 70 Levels T+72h Run at 00Z and 12Z ETKF for initial condition perturbations Stochastic physics: SKEB2 and random parameters Also a run at ECMWF out to 15 days (MOGREPS-15) Regional Component (MOGREPS-R) Runs over the North Atlantic and Europe (NAE) 18km, 70 Levels T+54h Run at 06Z and 18Z with boundary conditions from MOGREPS-G Coming soon (2012): MOGREPS-UK! MOGREPS Met Office Global and Regional Ensemble Prediction System 24 members | Operational since Sept 2008 after 3-years of trials
Julian Heming’s code to identify and track tropical cyclones (TC) in the deterministic global Unified Model is used. TCs are identified where 850hPa RV maxima are greater than a threshold MOGREPS TC Tracking • Search radius of 4 deg for analysis and 5 deg for forecast positions • Identified storms that do not match with a named storm or a TC identified at a previous time are counted as TC genesis
Products for named and potential storms on a basin by basin basis.
TOMAS: MOGREPS-15 12Z North Atlantic forecast on Wednesday 27th October 2010.
Tomas: MOGREPS-15 00Z North Atlantic forecast on Saturday 30th October 2010.
Tomas: MOGREPS-15 named storm forecasts 2010103012 -2010110400 Sat 30th Oct Thur 4th Nov
Ike September 4th 2008 at 12Z ECMWF UKMO MULTI
Comparison UKMO deterministic model to MOGREPS-15 ensemble Mean
Questions and answers Thanks to: Julian Heming and Helen Titley Ensembles teampiers.buchanan@metoffice.gov.uk