caa a22 4500 605472149 CHVBK 20210128100336.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00382-014-2264-8 doi (NATIONALLICENCE)springer-10.1007/s00382-014-2264-8 Role of the phase transition of intraseasonal oscillation on the South China Sea summer monsoon onset [Elektronische Daten] [Xie Shao, Ping Huang, Rong-Hui Huang] The present study investigates the role of intraseasonal oscillation (ISO) on the South China Sea (SCS) summer monsoon onset based on the daily reanalysis data for a 33-year period from 1979 to 2011. The SCS summer monsoon (SCSSM) onset always occurs during the developing phase of ISO at which the ISO develops from inactive convection and easterly anomalies to active convection and westerly anomalies. In the SCSSM onset season (April-July), the change rate of the zonal winds of ISO over the SCS is around twice as large as the increase rate of the climatological westerly winds. Therefore, the monsoon onset, which is a process requiring the westerly winds to increase up to a certain threshold, only occurs during ISO's developing phase. Furthermore, the monsoon onsets tend to occur at the active (inactive) convection and developing phase of ISO in the early (late) onset years. In the early-onset years, a strong active phase of ISO is needed to prompt monsoon onset because of the undeveloped climatological easterly winds at the onset period, whereas in the late-onset years the developed climatological westerly winds will prompt the monsoon onset as long as the suppressive role of the inactive phase of ISO starts relieving. Due to the constraint of ISO's developing phase on the SCSSM onset, an earlier ISO's developing phase occurring in the monsoon onset season will induce an earlier SCSSM onset. The low-frequency variation, with a period greater than 90days, can also modify the role of ISO's developing phase, especially when the developing phase of ISO occurs at the early season of the monsoon onset. Springer-Verlag Berlin Heidelberg, 2014 Intraseasonal oscillation (ISO) nationallicence South China Sea summer monsoon (SCSSM) nationallicence Monsoon onset nationallicence Shao Xie Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, 100190, Beijing, China aut Huang Ping Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, 100190, Beijing, China aut Huang Rong-Hui Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, 100190, Beijing, China aut Climate Dynamics Springer Berlin Heidelberg 45/1-2(2015-07-01), 125-137 0930-7575 45:1-2<125 2015 45 382 https://doi.org/10.1007/s00382-014-2264-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00382-014-2264-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shao Xie Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, 100190, Beijing, China aut NATIONALLICENCE 700 1- Huang Ping Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, 100190, Beijing, China aut NATIONALLICENCE 700 1- Huang Rong-Hui Center for Monsoon System Research, Institute of Atmospheric Physics, Chinese Academy of Sciences, 100190, Beijing, China aut NATIONALLICENCE 773 0- Climate Dynamics Springer Berlin Heidelberg 45/1-2(2015-07-01), 125-137 0930-7575 45:1-2<125 2015 45 382