NAO Influence on the MJO and its Prediction Skill in the Subseasonal-to-Seasonal Prediction Models

Abstract Based on the database of Subseasonal to Seasonal (S2S) Prediction project World Weather Research Programme (WWRP) / Climate (WCRP), influence North Atlantic Oscillation (NAO) Madden- Julian (MJO) and its forecast skill is investigated. It found that most models can capture MJO phase changes following positive negative NAO events. About 20 days after initialized with a (negative) NAO, appears more frequently in 7 (3), which corresponds reduced (enhanced) convection tropical Indian Ocean enhanced (suppressed) western Pacific. In S2S prediction dependent amplitude initial condition. A strong leads better than weak NAO. The tends be higher when starts from These results indicates there Northern extratropical skill. important for numerical represent improve simulation MJO.