Articles | Volume 15, issue 1
Nonlin. Processes Geophys., 15, 81–94, 2008

Special issue: Predictability in Earth Sciences

Nonlin. Processes Geophys., 15, 81–94, 2008

  08 Feb 2008

08 Feb 2008

An update on THORPEX-related research in data assimilation and observing strategies

F. Rabier1, P. Gauthier2, C. Cardinali3, R. Langland4, M. Tsyrulnikov5, A. Lorenc6, P. Steinle7, R. Gelaro8, and K. Koizumi9 F. Rabier et al.
  • 1CNRM/GAME, Météo-France and CNRS, France
  • 2Department of Earth and Atmospheric Sciences, UQAM, Montréal, Canada
  • 3European Centre for Medium-range Weather Forecasts, Reading, UK
  • 4Naval Research Laboratory, USA
  • 5Hydrometeorological Research Centre of Russia, Russia
  • 6The Met-Office, UK
  • 7Bureau of Meteorology Research Centre, Australia
  • 8NASA/Global Modelling and Assimilation Office, USA
  • 9Japanese Meteorological Agency, Japan

Abstract. The international programme "THORPEX: a World Weather Research Programme" provides a framework in which to tackle the challenge of improving the forecast skill of high-impact weather through international collaboration between academic institutions, operational forecast centres, and users of forecast products. The objectives of the THORPEX Data Assimilation and Observation Strategy Working Group (DAOS-WG) are two-fold. The primary goal is to assess the impact of observations and various targeting methods to provide guidance for observation campaigns and for the configuration of the Global Observing System. The secondary goal is to setup an optimal framework for data assimilation, including aspects such as targeted observations, satellite data, background error covariances and quality control. The Atlantic THORPEX Regional campaign, ATReC, in 2003, has been very successful technically and has provided valuable datasets to test targeting issues. Various data impact experiments have been performed, showing a small but very slightly positive impact of targeted observations. Projects of the DAOS-WG include working on the AMMA field experiment, in the context of IPY and to prepare the future THORPEX-PARC field campaign in the Pacific by comparing sensitivity of the forecasts to observations between several groups.