Variation Characteristics Of Wind Velocity And Wind Energy Of The Latest30Years In China

Based on the data of298meteorological stations and137sounding stations in China, NECP/NCAR reanalysis monthly mean data from1980to2009, the spatial-temporal evolution of the annual mean wind velocity and wind energy of the latest30years in China are studied, and on this basis, the associated atmospheric circulation features are also discussed. The results show that:(1) The annual average wind velocity on10m of China has the decreasing trend during the period of1980-2009, at the rate of approximately-0.136m/s/10a. It is also showed the declining trends of wind velocity exist over the broad areas of China, especially in the northeast China, east Inner Mongolia and coastal areas. Results show that in the troposphere the annual and seasonal average wind speed decreases during the period analyzed, the stratospheric wind speed, however, increases in the same period. There are negative (positive) correlations between both annual and seasonal mean surface wind velocity averaged for China and the indices of meridional (zonal) circulation both over Asia and Eurasia. Furthermore, The Arctic Oscillation (AO) index during winter is negative correlated with contemporaneous surface wind velocity averaged for China. The SVD analysis indicates strong (weak) AO pattern is well accordance to the weak (strong) mean wind velocity over China. Composite analysis further demonstrates the activity of cold air accompanied by AO anomaly is an important factor which affects the surface wind velocity.(2) The surface wind velocity over the east side of Tibetan Plateau significantly decreases, with obvious interdecadal characteristic. The annual and seasonal mean wind velocity of the study area turn strong in the mid-1990s, and this interdecadal variations have close positive relationships with the extend and area of Northern Hemisphere subtropical high.(3) The trends in annual wind energy density on10m significantly decrease of the latest30years. It is also showed the declining trends of wind energy density exist over the broad areas of China. Using EOF analysis and REOF analysis, China can be divided into seven sections with different temporal and spatial characteristics of wind energy. Our country has advantages in resources, needs and environmental protection, but has disadvantages in management, equipment manufacturing, cost control, service facilities and data collection. When making overall plans for the future wind energy projects, improving independent innovation capability and management of wind turbine manufactures, and saving the cost of electricity, which can greatly accelerate the development process of China wind energy generation field.