Some Highlights from the Progress and Plans of the World Meteorological Organization's THORPEX (The Observing System Research and Predictability Experiment) Program

The THORPEX (The Observing System Research and Predictability Experiment) Program is a long-term effort within the World Meteorological Organization (WMO) to benefit society, the economy, and environmental stewardship through accelerating the rate of improvement in both the skill of 1 to 14-day forecasts of high impact weather and in society's utilization of forecast information. The WMO's World Weather Research Programme (WMO/WWRP) oversees the implementation phase of THORPEX, which began in January 2005. THORPEX was approved by the 14th Congress of the WMO and includes the participation of nations from the developed and developing world. Such a high level of international co-ordination in the global prediction and dynamics research arena has not been accomplished since the WMO's Global Atmospheric Research Program (GARP) effort, which ended in the late 1970s. As with GARP, an international effort is required as, for example, the medium range prediction over the continental North America can be sensitive to observations taken over most of the North Hemisphere. International Science (Shapiro and Thorpe 2004) and Implementation Plans (Expert Group THORPEX Implementation Plan, 2005) have been developed to guide the development and implementation of the program. The effort is defined in terms contributions to four research components: i) Observing Systems; ii) Data Assimilation and Observing Strategies; iii) Dynamical Processes and Predictability; iv) Societal and Economic Research and Applications. This invited presentation discusses some of the highlights of the progress and plans of the THORPEX including:

1) A strong societal and economic research and application component so that the advances in numerical weather prediction can better benefit society including through the mitigation of disasters in the developing world through efforts such as Health in Africa.

2) A developing collaboration with the World Climate Research Program on research topics of interest to both the weather and climate community's such as improved treatment of tropical convection and its impact on middle latitudes.

3) A major research contribution to the International Polar Year through the organization of a THORPEX cluster that includes the Greenland Flow Distortion Experiment, the Concordiasa effort in Antarctica, a large modeling and measurement effort in Canada and aspects of the THORPEX Pacific Asian Regional Campaign (T-PARC).

4) Moving the academic research and user community from deterministic to probablistic forecasts through collaboration of the international operational forecast centers to create the TIGGE (THORPEX Interactive Grand Global Ensemble) data set.

5) Two major field campaigns aimed at advancing knowledge and improving the prediction of high impact weather associated with Rossby wave triggering by convection and intense cyclogenesis. The first of these efforts is T-PARC organized primarily by the North American and Asian Regional Committees in 2008 followed by a European effort in 2010 or 2011. These efforts will also contribute to the design of the components of future global observing and forecast systems.