Spatio - Temporal Differentiation Of Temperature And Salt Variation In Northeast China Sea From 1945 To

The Sea Area Northeast of Taiwan located between Taiwan Island and the Ryukyu Islands across the subtropical and tropical. The Kuroshio carries a lot of high temperature and high salt seawater across Yilan ridge and flows northward into the East China Sea flowing through these area. And the Ryukyu current and North Equatorial current flow through the area. IPCC pointed out that the temperature of seawater in 700 m shallow in global scale rising. In this conditions, the trend of changes in temperature and salinity hydrological characteristics of seawater of this area with so submarine topography and currents is the focus of this paper.In this paper, the temperature data of points and the salinity data of typical section(A, B) of the sea area northeast of Taiwan for 12 months in 0-700 m layer picking up by matlab from the Ishii1945-2010 reanalysis data are used to cut into slice,cluster analysis, piecewise linear analysis and other methods to explore the structure of temperature, salinity of the sea area northeast of Taiwan in season variation,in month variation and interannual variation in the process the long-term trend, regional differences, as well as the influence factors.In order to understand the effects of climate change in China and provide an important basis for climate prediction.Analysis of the results, we draw the following conclusions:1、The interannual variations of the seawater temperature of the sea area northeast of Taiwan in 0-700 m deep during 1945-2010(1)In depth: The temperature of the seawater in upper layer showed increased,the temperature of intermediate water decreased slightly, the temperature of seawater in 400-700 m layer decreased.(2)In season: The increase temperature during spring and summer is larger than that in autumn and winter.From the variation of temperature in surface seawater, the rise of the temperature of the sea surface in winter is bigger than that in summer, the rise in spring and autumn is bigger than that in summer and is smaller than that in winter.2、The regional differences of the interannual variations of the seawater temperature of the sea area northeast of Taiwan in 0-700 m deep during 1945-2010(1)in depth: The temperature of the surface layer(0-100m) is mainly affectedby latitude; the temperature of the middle layer(100-300m) is mainly affected by the heat effect of the ocean currents, the temperature of the deep layer(300-700m) is mainly influenced by topography.(2)In location: The depth of the warming seawater is becoming shallow from the point of the Kuroshio in the East China Sea, the point near the entrance of the Kuroshio in the East China Sea, to the point inside of the North Pacific.3、The interannual variations of the seawater salinity of the sea area northeast of Taiwan in 0-700 m deep during 1945-2010(1) In depth: the maximum salinity of seawater is in the depth of 150-200 m. The surface salinity is smaller. The seawater salinity value of 100-300 m layer is large. The seawater salinity value of 300-700 m layer is decreases gradually.(2) Segment analysis: the interannual variation trend of the seawater salinity in two section(A\B) is falling as a whole. After segmenting, the seawater salinity during1945-1962 is increased; the seawater salinity during 1994-2010 is falling sharp. The trend of interannual variation during the period of 1963-1993 is not obvious and showed a slightly upward or downward trend. But the extreme values are appeared more frequently. The interannual fluctuation is big.(3)In season: The rise or the decline of the seawater salinity in autumn and winter are bigger than that in spring and summer. In the situation of the trend during1963-1993, the seawater salinity in spring and autumn is edged increased, but the seawater salinity in summer and winter is edged fallling.4、The influence factors of the interannual changes of the seawater salinity in the sea area northeast of Taiwan(1)The seawater in 50 m shallow appears low salt conditions, mostly because of the precipitation of rainfall and surface runoff;(2)The higher the salinity is affected by ocean currents, here is the main of Kuroshio bring high salt seawater and the western invasion from the eastern Western invasion.