Proceedings - C-SRNWP Project

HIRLAM Reference System developments and changes:
The new project leader for System and Applications, Xiaohua Yang, has formed a system
expert group around him. This group has been very active not only in preparing new
Reference System releases, but also in the upgrading of revision procedures and tools, the
initiation of code and script overhaul activities and the creation of improved internal
communication tools, such as new mailing lists and wiki pages on the HIRLAM internal web
site Hexnet. The system group has also provided support to developers and local system
managers in the case of (operational) problems.
During 2006, the following changes have been introduced, or prepared for introduction, in the
HIRLAM Reference System:
- HIRLAM version 7.0 (released in May 2006):
o Assimilation of AMSU-A observations
o The blending in of ECMWF large scale analyses in the HIRLAM analysis
- HIRLAM version 7.1 (expected release February 2007):
o An increase in horizontal and vertical resolution
o Introduction of a statistical balance and increased resolution structure functions
in the data assimilation system
o Introduction of 4D-VAR
o Assimilation of screen level parameters, AMV and MODIS winds
o Upgrade to RTTOV-8
o A moist turbulence TKE scheme
o A more advanced snow and forest surface parametrization
o A new mean and subgrid scale orography parametrization
o Sloping surface adaptations to the radiation scheme
o Introduction of an extensive package of postprocessing tools.
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