Multi-scale Spatial And Temporal Variation Of The Precipitation In Southern Yunnan

The special geographical position in southern Yunnan area is decided their diverse climate conditions, complex natural environment. In recent years, natural calamities and effect are increasing frequently year by year such as the drought and flood, and so on, leading to regional ecological environment deterioration, threat to regional economic and social sustainable development. There are plateau, and a basin and hills in the area, and the influence of principal factor is bigger, and the area is a typical climate changeful zone, so geologists and biologist take the extensive attention of the area.The paper use southern Yunnan64stations rainfall data, using the kriging interpolation method and Moran’s I methods and discusses the spatial clustering south yunnan multi-scale spatio-temporal variation. The main results are as follows:Spatial variation of Mean Annual Precipitation (MAP), Mean Wet Season Precipitation (MWSP), Mean Summer Precipitation (MSUP) and Mean Autumn Precipitation (MAUP) in the southern Yunnnan is in the high similar level, in general. which is showed decreasing trend from the southwest border zone, southern border zone (south) east department, to the north central plateau. And Spatial variation of Mean Spring Precipitation (MSPP), Mean Winter Precipitation (MWIP) and Mean Dry Season Precipitation (MDSP) is showed decreasing trend from south to north of the area, and is declined the less differentiation from the east, west two sides to the middleSpatial variation of CvAP, CvWSP and CvSUP in southern Yunnan in the high similar level, and is showed increasing trend from the southwest and the south, east to the north central plateau. Cv value of CAP, CWSP and CSUP from low to high is CAP, CWSP and CSUP.PCI of each station in southern Yunnan shows that MAP in south Yunnan province seasonal differentiation. And, the area quasi-strike-slip mainshock-aftershock along the border is high value area in spatial variation, and two obvious low area.CM4PM of the southern border and southeast plateau in the study area is appeared5-8months or turning to5-8months. CM4PM of the southwest of the study area and plateau of the middle of Yunnnan is appeared6-9months or turning to6-9months. Based on spatial variation of MAP MAPCI and CvAP of each site in1961-2007of the study area is divided into five sub-regions.MSUP of sub-region I and III is showed very significant and significantly decreasing trend. But MAP and MWSP of sub-region I and Ⅲ. and3indexes of the sub-region Ⅱ, Ⅳ and V, do not have a significant trend changes.MSUP of II is not showed significantly decreasing trend, but MAP and MWSP of sub-region Ⅱ is not showed significantly increasing trend. And compared with adjacent sub-regions, the sub-region II is showed transitional characteristics.MAP of every sub-region in southern Yunnan shows it is given priority to fluctuation change, and positive (negative) above-regions period is not continued over4years; Positive above-regions period of MAP is anomaly of non-domain-wide, and is occurred in the adjacent2-3sub-regions. Negative above-regions period of MAP in1987-1989is anomaly of domain-wide and negative above-regions period of MAP in2005-2006is showed in4sub-regions. MAP of sub-region is not appeared above2a positive above-regions period, and is appeared twice over5a negative above-regions period surface.MWSP of each sub-region shows it is given priority to fluctuation change, but is showed4-6positive (negative) above-regions period. Positive above-regions period of MWSP is anomaly of non-domain-wide, and is occurred in the adjacent2-3sub-regions. Negative above-regions period of MWSP in1987-1989is anomaly of domain-wide and negative above-regions period of MWSP in2003-2006is showed in4sub-regions.MSUP of every sub-region shows it is given priority to fluctuation change, but is showed3-6positive (negative) above-regions period. Positive above-regions period of MSUP in1968-1971and1997-1998is anomaly of domain-wide. Negative above-regions period of MWSP in1987-1990is anomaly of domain-wide. There is the long cycle (9a,11a,22a) features in sub-regions Ⅱ-Ⅴ of MSUP.