Determination of the Drag Coefficient over the Tibetan Plateau

In this paper, a preliminary study is given on the drag (i.e. bulk transfer for momentum) coefficient, on the basis of data from four sets of AWS in Tibet during the first observational year from July 1993 to July 1994 according to China-Japan Asian Monsoon Cooperative Research Program. The results show that the drag coefficient over the Tibetan Plateau is 3.3 to 4.4 10-3. In addition, monthly and diurnal variations of drag coefficient and the relation-ship among the drag coefficients and the bulk Richardson number, surface roughness length and wind speed at 10 m height are discussed in detail.