Description of the upgrade

This new version includes:
  1. new parametrization schemes for the land surface, lying snow and sea-ice;
  2. new (RRTM) long wave radiation scheme;
  3. improved ozone model;
  4. use more TOVS/ATOVS data (HIRS-12, AMSU-14; less constraint on AMSU-8; more off-nadir data)
  5. revised snow analysis;
  6. revised observation and background error variances;
  7. use of buoys platform heights;
  8. digital filter for gravity wave constraint.

Implemented: 27 June 2000