US CLIVAR MJO Working Group: Efforts to Establish and Improve Subseasonal Predictions

In spring 2006, US CLIVAR established the Madden-Julian Oscillation (MJO) Working Group (MJOWG). The formation of this 2-year limited lifetime WG was motivated by: 1) the wide range of weather and climate phenomena that the MJO interacts with and influences, 2) the fact that the MJO represents an important, and as yet unexploited, source of predictability at the subseasonal time scale, 3) the considerable shortcomings in our global climate and forecast models in representing the MJO, and 4) the need for coordinating the multiple threads of programmatic and investigator level research on the MJO. Near-term tasks involve the development of diagnostics for assessing model performance in both climate simulation and extended-range/subseasonal forecast settings as well as develop a consistent and coordinated approach to subseasonal, specifically MJO, forecasting. At present this effort includes participation from NCEP, ECMWF, BMRC, UKMO, CMA and ESRL/NOAA. The purpose of this presentation is to make the community aware of these activities. This will include discussing the diagnostics that have been developed for assessing model performance in simulating/predicting the MJO, show results of their application to a number of present-day GCMs, and also discuss the MJO forecast metrics and the plans to develop a multi-model ensemble forecast for the MJO. For additional details, see www.usclivar.org.