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Under the background of a warming climate,regional climate responsesmay be different from place to place.How cold extreme events in China respond isstill an open question.This study investigates responses of coldwave frequency (CWF)in China from observation and modeling perspectives.Observational evidences showthat CWF significantly reduces across China during the warm period (1978-2009) incomparison with that during the cold period (1957-1977),concurrent with extremevalue centers located in northern China during 1957-1977and southern China during1978-2009.The Empirical Orthogonal Function (EOF) leading mode of CWF in thecold period is also dominant by an extreme value center prevailing over northernChina,while the center exhibits a southward shift in the warm period.Aseven-member multi-model ensemble (MME) from Coupled Model IntercomparisonProject#3(CMIP3) shows that southern China tends to experience more coldwavesthan northern China in the 21st century (2045-2064and 2080-2099) under the globalwarming A1B forcing (with atmospheric CO2concentration of 720ppm).This featurecan also be seen in the leading EOF mode of MME.These results indicate that theprimary response of CWF to a warming climate may be the southward shift of the maximum loading center.The enhanced western Pacific Subtropical High andweakened Siberian High during 1978-2009may result in anomalous southerlieswhich bring warm and wet air to southern China.Meanwhile cold and dry air istransported from the north via a “northwest pathway” to southern China.Under thejoint action of these two air masses,coldwaves may easily generate in southern Chinaas observed in recent extreme cold events in this region.