Changing characteristics and spatial differentiation of spring precipitation in Southwest China during 1961-2012

In this study,we analyze spring precipitation from 92 meteorological stations spanning between 1961 and 2012 to understand temporal-spatial variability and change of spring precipitation over Southwest China.Various analysis methods are used for different purposes,including empirical orthogonal function（EOF） analysis and rotated EOF（REOF） for analyzing spatial structure change of precipitation anomaly,and the Mann-Kendall testing method to determine whether there were abrupt changes during the analyzed time span.We find that the first spatial mode of the precipitation has a domain uniform structure;the second is dominated by a spatial dipole;and the third contains five variability centers.The 2000 s is the decade with the largest amount of precipitation while the 1990 s is the decade with the smallest amount of precipitation.The year-to-year difference of that region is large：the amount of the largest precipitation year doubles that of the smallest precipitation year.We also find that spring precipitation in Southwest China experienced a few abrupt changes：a sudden increase at 1966,a sudden decrease at 1979,and a sudden increase at 1995.We speculate that the spring precipitation will increase gradually in the next two decades.

Some evidences for earthquake occurrence in the shallow crust in some areas of North China and Southwest China

The parameters of hypocentral location are important fundamental data for the study of seismology and the earth interior physics; among them, the focal depth is a very important one but can hardly be measured with higher precision. With the increase of seismic stations in number, the heightening of observation quality and the improvement of determination method, such a situation has been changed much. In this paper, the results of hypocentral location and re-location by 7 small-aperture digital seismic station networks at Tangshan, Zhangbei and Huailai of Hebei Province, Datong of Shanxi Province and Jianchuan, Luquan and Yao'an of Yunnan Province are used. Using these results together with those of focal depth inversion by far-field data of some individual large shocks in corresponding areas and those re-determined by the Linfen telemetered seismic network of Shanxi Province, a comparison with the results of focal depth determination in the past earthquake catalogues is made. It is found out that the focal depths determined by the small-aperture seismic networks are basically distributed in the range from the earth surface to ten-odd kilometers underground. In contrast, the focal depths determined in the past are mostly distributed at the depth range from the earth surface to 30 km underground. Besides, there is a difference of 50% to 100% between the average values of the two cases, which is quite an obvious one. From the result of analysis, it is considered that the results determined by the small-aperture seismic networks may be closer to the reality of focal depths distribution. That is to say, earthquakes in the above-mentioned areas should be distributed in the shallow part of the crust. The causes that lead to the above situation are discussed preliminarily, and some suggestions and measures for improving the precision of focal depth determination are put forward.

Impact of Economic Transformation on Energy Demand in Southwest China and Forecast

"Economic transformation"has become the main path to promote China's social and economic development,and many regions have increased the importance and attention to"economic transformation",and the Southwest region is no exception.Many cities in Southwest China are developing new energy sources to promote economic development and economic transformation.Economic transformation and economic development in Southwest China are mutually influencing and interacting,while energy development in Southwest China and its local economic development are mutually promoting and influencing,so economic transformation also affects energy demand and development in Southwest China.The importance of economic transformation should be taken into consideration.

Seismic motion attenuation relations in Sichuan and adjacent areas

The Sichuan and adjacent areas is divided into southwest China region （SWCR） and Sichuan Basin region （SCBR） according to tectonic backgrounds and seismic damage distribution features. 96 modem destructive earthquakes in SWCR and 40 in SCBR are gathered respectively. All their magnitude parameters are checked. Based on the statistic relations between epicentral intensity and magnitude as well as relation between sensible radius and magnitude, the near and far field seismic intensity attenuation features are represented and controlled. And then the seismic intensity attenuation relations along major axis, minor axis and mean axis are established separately. The system-atic deviations of surface wave magnitude between China seismograph network and U.S. seismograph network are considered in this paper. By making use of the new attenuation relations of bedrock horizontal ground acceleration response spectrum in west U.S., the attenuation relations of bedrock horizontal ground acceleration response spec- trum in SWCR and SCBR are digital transformed based on the attenuation model considering acceleration saturation of distance and magnitude in near field.