Uncertainties in the global wind analysis: implication for the minimum requirements of Doppler wind lidar measurements for seasonal climate studies

This study examines the uncertainties in the seasonal global wind analysis by comparing the wind analysis from NCEP/DOE reanalysis II and ERA-40 reanalysis data products during 1980-1999. Significant differences are found in seasonal mean wind field between the two reanalyses. Preliminary results show that the differences are mainly distributed in the tropical and Polar regions of the troposphere and in the sub- tropical areas of the upper atmosphere, which implies uncertainties in the wind analysis and a lack of wind observations in these areas. Seasonal and height variations are also found in the uncertainties of the wind analysis. More detailed studies are conducted to investigate the seasonal and year-to-year variability of these uncertainties. The implication of the analysis results on the minimum requirement of the future space- based Doppler Wind Lidar measurements for seasonal climate study is discussed.