Cycle 30r1summary of changes

Implementation date

1 February 2006

Key characteristics of our current forecasting system  

Horizontal changed

  • Atmospheric
    • HRES: TL799
    • ENS: TL399
  • Wave
    • HRES: 0.36 degrees
    • ENS: 0.5 degrees
    • LAW: 0.1 degrees

Vertical changed

  • Atmospheric
    • HRES: L91
    • ENS: L62
Data set affected
  • HRES
  • ENS
  • Wave
Meteorological changes
  • Increase wave spectral resolution to 24 directions and 30 frequencies (from 12 and 25 respectively) for the EPS ocean wave model.
  • Use of grid-point humidity and ozone in 4D-Var.
  • Revised coefficients (version 2.3) for the linearised ozone chemistry scheme, supplied by Daniel Cariolle, CERFACS.
  • Use of Jason altimeter wave height data and ENVISAT ASAR spectra in the wave model data assimilation. ERS-2 SAR spectra are no longer assimilated.
Meteorological impacts
  • small but statistically significant improvements to deterministic 500 hPa height forecasts over Europe and for both extra-tropical hemispheres out to day 6.
  • overall impact on weather parameters is modest
  • precipitation scores over Europe are consistently improved, in particular for large daily rainfall amounts
  • tropical temperature and wind forecasts are generally better when verified against radiosondes
  • tropical cyclone position and intensity forecasts are improved in the high resolution system with some spectacular results for intense hurricanes
  • increased number of observations used in the assimilation with better analysis and background departure statistics
  • beneficial impact on the ocean wave analyses.
  • improvements in the ocean wave forecasts


  • overall benefit of the higher resolution for the ENS is reflected in the results for the probability scores which are consistently improved for 500hPa height anomalies
  •  improvement of the evaluation of precipitation events over Europe with respect to the Brier and ROC area scores
Technical changes  
Model ID
  • Atmospheric: 127
  • Ocean wave: 116
  • Limited-area ocean wave: 216
New disseminated model output  
Discontinued disseminated model output -  
e-suite experiment number 0029