COMPOSITE ANALYSIS OF SUMMER MONSOON ONSET PROCESS OVER SOUTH CHINA SEA

XU Hai-ming; HE Jin-hai; ZHOU Bing

Abstract:

Based on the method of composite analysis, the onset process and preceding signs of summer monsoon over the South China Sea (SCS) is investigated. The result indicates that convection activities appear first over the Indo-China Peninsula prior to the onset of the monsoon, then around the Philippines just at the point of onset, implying that the convection activities around the Philippines serve as one of the reasons leading to the SCS monsoon onset. Before the SCS monsoon onset, the equatorial westerly over the Indian Ocean (75°E 95°E ) experiences noticeable enhancement and plays an important role on the SCS monsoon onset. It propagates eastward rapidly and causes the establishment and strengthening of equatorial westerly in the southern SCS, on the one hand, it results in the migration southward of the westerly on south side of the south-China stationary front by means of shift northeastward of the westerly and convection over the Bay of Bengal, on the other. Further study also shows that the intensification of equatorial westerly in the Indian Ocean (75°E 95°E) and the southern SCS is closely related to the reinforcement of the Southern-Hemisphere Mascarene high and Australian high, and cross-equatorial flow northward around Somali, at 85°E and 105°E, respectively.

Get Citation+

XU Hai-ming, HE Jin-hai, ZHOU Bing. COMPOSITE ANALYSIS OF SUMMER MONSOON ONSET PROCESS OVER SOUTH CHINA SEA [J]. Journal of Tropical Meteorology, 2001, 7(1): 29-40.

Export:

Article Metrics

COMPOSITE ANALYSIS OF SUMMER MONSOON ONSET PROCESS OVER SOUTH CHINA SEA

Department of Atmospheric Sciences, Nanjing Institute of Meteorology

Abstract: Based on the method of composite analysis, the onset process and preceding signs of summer monsoon over the South China Sea (SCS) is investigated. The result indicates that convection activities appear first over the Indo-China Peninsula prior to the onset of the monsoon, then around the Philippines just at the point of onset, implying that the convection activities around the Philippines serve as one of the reasons leading to the SCS monsoon onset. Before the SCS monsoon onset, the equatorial westerly over the Indian Ocean (75°E 95°E ) experiences noticeable enhancement and plays an important role on the SCS monsoon onset. It propagates eastward rapidly and causes the establishment and strengthening of equatorial westerly in the southern SCS, on the one hand, it results in the migration southward of the westerly on south side of the south-China stationary front by means of shift northeastward of the westerly and convection over the Bay of Bengal, on the other. Further study also shows that the intensification of equatorial westerly in the Indian Ocean (75°E 95°E) and the southern SCS is closely related to the reinforcement of the Southern-Hemisphere Mascarene high and Australian high, and cross-equatorial flow northward around Somali, at 85°E and 105°E, respectively.

HTML

Reference (15)

[1]	TAO Shi-yan, CHEN Long-xun.. A review of recent research on East Asian summer monsoon in China [A].Monsoon Meteorology [M], Oxford: Oxford University Press, 1987. 60-92.
[2]	HE Hai-yan, MCGINNIS J W, SONG Zhen-shen, et al. Onset of the Asian summer monsoon in 1979 andthe effect of the Tibetan Plateau [J]. Monthly Weather Review, 1987, 115: 1966-1995.
[3]	HE Jin-hai, ZHU Qian-gen, MURAKAMI M. TBB data-revealed features of Asian-Australian monsoon seasonaltransition and Asian summer monsoon establishment [J]. Journal of Tropical Meteorology, 1996, 12:(1) 34-42.
[4]	MURAKAMI T, CHEN Long-xun, XIE An. Relationship among seasonal cycles, low-frequency oscillationsand transient disturbances as revealed from outgoing longwave radiation data [J]. Monthly Weather Review,1986, 114: 1456-1465.
[5]	CHEN T C, CHEN J M. An observational study of the South China Sea monsoon during the 1979 summer:onset and life cycle [J]. Monthly Weather Review, 1995, 123: 2295-2318.
[6]	CHANG C P, CHEN T J. Tropical circulation associated with southwest monsoon onset and westerly surgeover South China Sea [J]. Monthly Weather Review, 1995, 123: 3254-3267.
[7]	XIE An, ZHANG Zhen-zhou. Advance of the summer monsoon over the South China Sea [J]. Acta MeteorologicaSinica, 1994, 52 (3): 374-378.
[8]	XIE An, LIU Xia, YE Qian. Climatological features in the onset of South China Sea [A]. HE Jin-hai. Latestadvances in the study of Asian monsoon [M]. Beijing: Meteorological Press, 1996, 132-142.
[9]	LIU Xia, XIE An, YE Qian, et al. The climatic characteristics of summer monsoon onset over South ChinaSea [J]. Journal of Tropical Meteorology, 1998, 14: 28-36.
[10]	CHEN Long-xun, LIU Hong-qing, WANG Wen, et al. Preliminary study on the characteristics andmechanism of summer monsoon onset over South China Sea and region adjacent to it [J]. Acta MeteorologicaSinica, 1999, 57: 16-28.
[11]	CHEN Long-xun, ZHU Qian-gen, LUO Hui-bang, et al. Monsoon in East Asia [M] Beijing: MeteorologicalPress, 1991, 89-92.
[12]	HUANG Shi-song, TANG Ming-min. On the structure of the summer monsoon regime of East Asia [J].Scientia Meteorologica Sinica, 1987, 7 (3): 1-16.
[13]	HUANG Shi-song, TANG Ming-min. Medium-range ocillations of the atmosphereic circulation systemsover the northwestern Pacific and southern Indian Oceans and their teleconnection [J]. Scientia MeteorologicaSinica, 1988, 8 (4): 1-13.
[14]	YANG Xiu-qun, HUANG Shi-song. The influence of intensity change of Mascarene high on the generalcirculation of atmosphere - a numberical experiment [J]. Scientia Meteorologica Sinica, 1989, 9 (2):126-138.
[15]	WANG Li-juan, HE Jin-hai, XU Hai-ming, et al. Abrupt change in elements around the 1998 SCS summermonsoon establishment with analysis of its characteristic process [J]. Journal of Nanjing Institute ofMeteorology, 1999, 22 (2): 135-140.

COMPOSITE ANALYSIS OF SUMMER MONSOON ONSET PROCESS OVER SOUTH CHINA SEA

Abstract:

References

Get Citation+

Share Article

Article Metrics

Proportional views

Manuscript History

Online:

通讯作者: 陈斌, bchen63@163.com