[ACG44-P09] Influence of global warming on Eurasian snow cover teleconnection to the Indian monsoon rainfall using a large ensemble AGCM experiment
Keywords:Indian monsoon, Eurasian snow cover, Teleconnections, Global warming
Carefully conducted correlation and composite analysis showed that the global warming has a possible weakening effect on the ESC-ISMR inverse relationship. This impact seems to be inflicted upon the ISMR with a modulation in the summer walker circulation anomaly over the South/South-East Asian region. Based on the correlation analysis, the impact of the global warming was shown to be less than the change observed from the observation-based analysis. Therefore, recent (after 1990) and past (before 1990) time slices were analyzed using correlation and composite based methods to observe any apparent deviations. Both ensemble simulations with and without human influence showed a similar decrease of the negative relationship with a westward shift of the rising anomalies associated with Indian ocean walker circulation during recent heavy snow years. This result was consistent with observations, suggesting a low-frequency variation of the circulation patterns associated with the ESC-ISMR relation due to the stochastic nature of the processes occurs from the natural variability, independent from global warming. Based on these results, we speculate that although an apparent weakening impact from global warming has occurred, more dominant low-frequency variability might be the reason for the significant reduction of ESC-ISMR correlation during recent decades.