Page History

The resolution of one-week ensemble prediction model of JMA was upgraded on 21 November 2007.

Major changes are:

• Increase in the resolution from TL159L40 to TL319L60 with a topmost level raised from 0.4hPa to 0.1hPa.
• Use of a new high-resolution analysis of sea surface temperature and sea ice concentration as ocean surface boundary conditions.
• Use of surface snow depth data from the domestic dense observational network in the global snow depth analysis.
• Introduction of a convective triggering scheme into the deep convection parameterization.
• Introduction of a new 2-dimensional aerosol climatology derived from satellite observations for the radiation calculation.
• Increase in the resolution of inner loop model of the four-dimensional variational (4D-Var) data assimilation system from T106L40 to T159L60.
• Introduction of a sigular vector method to make the initial perturbations.

Notes:

• The resolution and parameters of TIGGE data from JMA remains unchanged.
• Orography and Land Sea Mask in TIGGE data are slightly different from the previous data associated with the model change.

The Met Office Global model was upgraded to OS45 with effect from the 12UTC cycle on 5 May 2022.

• The Global Atmosphere-Land Model is now fully coupled to a ¼ degree interactive Ocean Model in both 10km deterministic and 20km MOGREPS-G ensemble configurations, with both the atmospheric and ocean models exchanging information hourly.
• The atmosphere-land model has been upgraded from GA7.2.1GL8 to GA8GL9.
• New observations have been introduced from radiosonde descents, Sentinel, Aeolus and Mode-S in Europe.