Summary of Abstract Submission

Abstract Submission No. IO50-05-0054PresentationPoster

PREDICTABILITY OF WESTERN PACIFIC SUBTROPICAL HIGH AND ITS RELATIONSHIP WITH EAST ASIAN SUMMER MONSOON IN ECMWF SYSTEM-4 COUPLED MODEL

DHRUVA KUMAR PANDEY*1, SHAILENDRA RAI 1, N.K.SHAHI1, NISHANT MISHRA1

1 KBCAOS, FACULTY OF SCIENCE, UNIVERSITY OF ALLAHABAD, INDIA

ABSTRACT :

This study investigates the variability and predictability of WPSH and East Asian summer rainfall during boreal JJA season for 1982-2013 from the European Centre for Medium-Range Weather Forecasts (ECMWF) System 4 coupled model. The predictability of EASM and WPSH from the model is high as the anomaly correlation skills are 0.78 and 0.77 respectively. However, the temporal correlation coefficient between model produced and observed precipitation for JJA season over East Asia region (5šN-40šN, 110šE-140šE) is low(cc=0.38). The interannual variability of WPSH is inversely related to EASM as the correlation coefficients between EASM and WPSH for model and observation are -0.84 and -0.92 respectively. Empirical Orthogonal Function (EOF) analysis is performed over geopotential height anomalies for model and observation. The dominant EOF mode of observation shows indo-pacific warm pool of oceans. The second EOF mode for observation demonstrates that the WPSH variability is strongly related to Central Pacific sea surface temperature anomalies and the same is true for the model. The WPSH index and EASM index are also predicted from the regression model for the observation. The correlation coefficients between regressed WPSH with observed WPSH index and regressed EASM with EASM index are 0.74 and 0.71 respectively. The observed precipitation over the East Asia region is also predicted from the regression model. The prediction that obtained from regression model (cc=0.50) is improved significantly compared to the coupled model (cc=0.38).