Datasets affected

• HRES
• ENS

Resolution

Unchanged

Meteorological content

• Revised snow scheme including a diagnostic liquid water storage and a new density formulation
• Revised ozone chemistry
• Active assimilation of IASI humidity channels and consistent use of AIRS and IASI humidity channels.
• Activate all-sky 4D-VAR assimilation of microwave imagers
• Increase of the weight to GPS radio occultation data above 26 km, and use of the data up to 50 km
• Various satellite-related modifications, including activation of version 9 of the radiative transfer software package RTTOV-9 (developed by NWP-SAF) and revised HIRS cloud detection
• TL/AD longwave radiation (removal of the neural network), optimization of the non-linear code for simplified longwave radiation and optimization (NL, TL, AD) of the shortwave radiation scheme
• Extend the domain of the wave model from 81 º to 90 º North
• Use of ERA-interim analyses for the EFI reforecasts

Meteorological impact

• Improvements to 2m temperature bias and slightly better performance for recent tropical cyclones in both position and intensity.
• Synoptic performance is generally similar to current operations.
• Impact on EFI from the change to using ERA-interim analyses for its reforecasts is not substantial.

Technical content

Model ID and experiment number

• Atmospheric: 134
• Ocean wave: 119
• Limited-area ocean wave: 219

E-suite experiment number = 0042

Resources

ECMWF Newsletter: See Newsletter 121