Index of direction change of zonally averaged wind and change of season

ZHU Min; XU Jian-xia; ZHANG Ming

Abstract:

In this paper, a Wind Direction Change Index (WI), which can describe four-dimensional spatiotemporal changes of the atmospheric circulation objectively and quantitatively, is defined to study its evolution and seasonal variation. The first four modes can be obtained by EOF expansion of the zonally averaged WI. The first mode reveals the basic spatial distribution of the annually averaged WI. The second mode reflects the quasi-harmonic parts of the WI deviations. Tropical, subtropical and extratropical monsoon areas can be clearly reflected by this mode. The third mode reflects the non-harmonic parts of the WI deviations. It shows the so-called February reverse in stratospheric atmosphere as well as the asymmetric seasonal changes from spring to fall and from fall to spring due to both the land-sea distribution contrast between the Northern and Southern Hemispheres and the nonlinear effect of atmospheric and ocean fluids. The fourth mode reveals the northward advancing of the global reversed wind fields from spring to summer and their southward withdrawal from summer to autumn.

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ZHU Min, XU Jian-xia, ZHANG Ming. Index of direction change of zonally averaged wind and change of season [J]. Journal of Tropical Meteorology, 2011, 17(2): 128-135.

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Index of direction change of zonally averaged wind and change of season

Laboratory of Atmospheric Circulation and Short-Range Climate Forecast, Meteorological College, PLA University of Science and Technology

Abstract: In this paper, a Wind Direction Change Index (WI), which can describe four-dimensional spatiotemporal changes of the atmospheric circulation objectively and quantitatively, is defined to study its evolution and seasonal variation. The first four modes can be obtained by EOF expansion of the zonally averaged WI. The first mode reveals the basic spatial distribution of the annually averaged WI. The second mode reflects the quasi-harmonic parts of the WI deviations. Tropical, subtropical and extratropical monsoon areas can be clearly reflected by this mode. The third mode reflects the non-harmonic parts of the WI deviations. It shows the so-called February reverse in stratospheric atmosphere as well as the asymmetric seasonal changes from spring to fall and from fall to spring due to both the land-sea distribution contrast between the Northern and Southern Hemispheres and the nonlinear effect of atmospheric and ocean fluids. The fourth mode reveals the northward advancing of the global reversed wind fields from spring to summer and their southward withdrawal from summer to autumn.

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[1]	ZHU Ke-zhen. Southeast monsoon and rainfall in China [J].J. Geograph. Soc. China (in Chinese) [J]. 1934, 1(1): 1-27.
[2]	TU Chang-wang, HUANG Shi-song. The advance andretreat of the Summer Monsoon in China [J]. Meteor. Mag. (inChinese) [J]. 1944, 18: 81-92.
[3]	TU Chang-wang. China weather and world oscillation withapplication to long-range forecasting to floods and drought ofChina during the summer [J]. Meteor. Mag. (in Chinese), 1937,13(11): 647-697.
[4]	LI Jian-ping, ZENG Qing-cun. A new monsoon index, itsinterannual variability and relation with monsoon precipitation[J]. Clim. Environ. Res., 2005, 10(3): 351-365.
[5]	ZUO Rui-ting, ZENG Qing-cun, ZHANG Ming. Thenumerical simulation of monsoon and the correlation betweenmonsoon and Westerlies [J]. Sci. Atmos. Sinica (in Chinese),2004, 28(1): 7-22.
[6]	ZUO Rui-ting, WANG Li-qiong, CAI Dan. The stabilityand interdecadal variability of global monsoon system [J].Clim. Environ. Res., 2005, 10(3): 342-350.
[7]	HE Jin-hai, ZHU Qian-gen, MURAKAMI M.Characteristics of Asian summer monsoon establishment andAsian-Australian monsoon seasonal transition by TBB data [J].J. Trop. Meteor., 1996, 12(1): 34-42.
[8]	ZENG Qing-cun, ZHANG Dong-ling, ZHANG Ming. Theabrupt seasonal transitions in the atmospheric generalcirculation and the onset of monsoons. Part I: Basic theoreticalmethods and its application to the analysis of climatologicalmean observations [J]. Clim. Environ. Res., 2005, 10(3):285-302.
[9]	XUE Feng, BI Xun-qiang, LIN Yi-hua. Modelling theglobal monsoon system by IAP 9L AGCM [J]. Adv. Atmos.Sci., 2001, 18: 404-412.
[10]	ZENG Qing-cun, ZHANG Bang-lin. On the seasons ofgeneral atmospheric circulation and the monsoon [J]. Sci.Atmos. Sinica (in Chinese), 1998, 22(6): 805-813.
[11]	XUE Feng, LIN Yi-hua, ZENG Qing-cun. On the seasonsof general atmospheric circulation and their abrupt changes.Part : Climatology [J]. Sci. Atmos. Ⅲ Sinica (in Chinese), 2002,26(3): 307-314.
[12]	ZHANG Bang-lin, ZENG Qing-cun. On the seasons ofgeneral atmospheric circulation and their abrupt changes. PartⅡ: Case study of particular years [J]. Sci. Atmos. Sinica (inChinese), 1998, 22(2): 130-136.
[13]	LI Jian-ping, ZENG Qing-cun. Significance of thenormalized seasonality of wind field and its rationality forcharacterizing the monsoon [J]. Sci. China (Ser. D) (inChinese), 2000, 30 (3): 331-336.
[14]	ZHU Min. The four-dimensional manifolds of Asiansummer monsoon and discussion of its dynamical mechanism[D]. Ph. D. dissertation (in Chinese), Meteorology College,PLA University of Science and Technology, 2007. 29-31.
[15]	ZENG Qing-cun. The Theory of Atmospheric InfraredRemote Sensing (in Chinese) [M]. Beijing: Science Press, 1974:158-166.
[16]	HUANG Jia-you. Statistical Analysis and Predictionmethods in Meteorology [M]. Beijing: China MeteorologicalPress, 2000: 135-139.
[17]	ORTHGRT N, CAHALAN BR, MOENG F J. Samplingerrors in the estimation of empirical orthogonal function [J].Mon. Wea. Rev., 1982, 110: 699-706.

Index of direction change of zonally averaged wind and change of season

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