Authors: Tingting Ma Zhiwei Wu Zhihong Jiang
Publish Date: 2012/04/05
Volume: 39, Issue: 9-10, Pages: 2487-2496
Abstract
Under the background of a warming climate regional climate responses may be different from place to place How cold extreme events in China respond is still an open question This study investigates responses of coldwave frequency CWF in China from observation and modeling perspectives Observational evidences show that CWF significantly reduces across China during the warm period 1978–2009 in comparison with that during the cold period 1957–1977 concurrent with extreme value centers located in northern China during 1957–1977 and southern China during 1978–2009 The empirical orthogonal function EOF leading mode of CWF in the cold period is also dominant by an extreme value center prevailing over northern China while the center exhibits a southward shift in the warm period A sevenmember multimodel ensemble MME from coupled model intercomparison project3 CMIP3 shows that southern China tends to experience more coldwaves than northern China in the twenty first century 2045–2064 and 2080–2099 under the global warming A1B forcing with atmospheric CO2 concentration of 720 ppm This feature can also be seen in the leading EOF mode of MME These results indicate that the primary response of CWF to a warming climate may be the southward shift of the maximum loading center The enhanced western Pacific Subtropical High and weakened Siberian High during 1978–2009 may result in anomalous southerlies which bring warm and wet air to southern China Meanwhile cold and dry air is transported from the north via a “northwest pathway” to southern China Under the joint action of these two air masses coldwaves may easily generate in southern China as observed in recent extreme cold events in this regionWe thank Dr Laurent Li from Laboratoire de Météorologie Dynamique IPSL/CNRS/UPMC Paris France and the two anonymous reviewers for helpful and valuable comments The authors are supported by the National Basic Research Program “973” Grant No 2010CB950401 and 2010CB428505 the Special Research Program for Public Welfare Meteorology of China under Grant No GYHY200906016 and a Project Funded by the Priority Academic Program Development PAPD of Jiangsu Higher Education Institutions
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