The spectral density technique is investigated as a basis for measuring turbulent fluxes of CO2 and water vapour over the sea using observations obtained on a well-designed pier of Kyoto University during September 20-22, 2000. By comparing the turbulent fluxes measured by the spectral density technique with those determined by the eddy correlation technique, a set of parameters of the non-dimensional gradient (φ) and Kolmogorov constant (α) was determined. The following parameters are the optimal selection under unstable conditions for the spectral density technique: φc = φq = (1 - 16z/L)-1/2; αc = 0.78 and αq = 0.76 Here, subscripts c and q refer to CO2 and water vapour; z is height and L is the Obukhov stability length. The present results demonstrate that with rugged sonic anemometer-thermometer sensors and computers, the spectral density technique applied over the sea has an accuracy comparable to that of the eddy correlation technique.
|出版ステータス||Published - 12月 2005|
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