The Characteristics Of The 50-year Climate Variability In Fujian Province

This study analyzes the climate variability of precipitation and temperature in Fujian province in the recent 50 years, and further investigates the predictability of the rainy season by analyzing the characteristics of physical fields and indexes prior to the rainy season. The data used in this study include the surface observational precipitation and temperature in 35 stations (observation period:1961-2003) and 5 other stations (observation period: 1951-2003, i.e. Fuzhou, Xiamen, Jianyang, Nanping and Pucheng) of Fujian province; global 2° × 2° grid Sea Surface Temperature (observation period: 1961-2002) provided by National Meteorological Center of China (NMCC), Northern hemisphere 5° × 5° 500hPa grid geopotential height (observation period: 1961-2002), and 5 parameters of subtropical high (Period: 1961-2002). In order to disclose the intrinsic relation between the climate variability and the general circulation, several statistical and synoptic methods are utilized in this study, such as Tendency Analysis (TA), Empirical Orthogonal Function (EOF) decomposition, Rotated EOF (REOF), running Root Mean Square Error (RMSE), and Correlation Analysis (CA).The interannual and seasonal climate variability of precipitation in Fujian province shows that the 40-year yearly precipitation generally tends to increase in the long-term tendency, and the positive tendency is more significant in the southern Fujian. Seasonally, the precipitation in the early spring, summer, fall and winter all indicates the weak increase. Precipitation decreases in the rainy season in whole province.REOF analysis shows that there exist 3 regions of the dominant precipitation patterns for the precipitation of the whole year, the raining season and summer, respectively, but the locations and areas are different for the three different spans. There also exist 2 regions of the dominant pattern in the early spring, fall and winter, respectively. The annual precipitation is heaviest in northern Fujian and lightest in southern Fujian while the positive tendency is more significant in southern Fujian.The decadal variability of precipitation is also investigated in this study. In the decadal scale of precipitation of the whole Fujian, the precipitation basically decreases from 1960's to the late of 80's, except slight increase in the early 1970's. The precipitation exist positive anomaly after 1990's, however, the oscillation is sharp and the flood and drought is pronounced from year to year. The decadal variations of precipitation are different in different season. The precipitation of summer, fall and winter is similar to the one of the whole year, i.e., positive anomaly, large oscillation, while negative anomaly in the early spring and raining season.The running RMSE analysis of the representative stations in respective region is...