D48   LAQ assimilation results.

Responsible partner
Due date

This is part of work-package 7100 and 7200 the purpose of which is inter comparison of the skills of different numerical weather prediction models when using GPS data. The work in the workpackages includes:

·     Document the impact of ground-based GPS data on NWP data assimilation and forecast systems
Compare the different assimilation methods used by TOUGH participants

Methodology/Work Description:
Carry out extensive, full-scale data assimilation experiments. Standard statistical methods will be used for objective verification. Analyses and forecasts with and without the ground-based GPS data will be verified against observations and analyses. This includes:

·        Optimisation of initial capability for assimilation of GPS data, including implementation of any necessary bias correction scheme (based on results from WP 6000)

·        Parallel, quasi-operational, assimilation in demonstration mode for a period of at least one month.

·        Generation of individual case studies of regional interest for detailed study. Cases will be biased towards more extreme events and/or where current operational models give poor guidance on an event.

·        Verification using both objective and subjective verification methods.

·        Comparison and appraisal of the different assimilation methods

Deliverable.  The results of the impact studies and model development done at LAQ can be found in the articles:

Facani, C., R. Ferritti, C. Dimini, F.-S. Marzano, A. Memmo, L. Cucurull: Simulation of deep concection in the Mediterranean area using 3DVar of conventional and non-conventional data. Advances in Geosciences, vol 2, p. 65, 2005.

Ferretti, R, C. Faccani, M. Francia and L. Cucurull: Operational evaluation of the assimilation of a network of ground based GPS PW and ZTD into the weather forecast. Manuscript submitted to Mon Wea. Rev. 2006.