Monin-Obukhov Similarity Theory for Carbon Dioxide, Water Vapor and Vertical Wind Velocity

The Monin-Obukhov similarity theory for carbon dioxide (c) and water vapor (q) is investigated using data obtained over a rice field. First, the similarity theory is applied to the standard deviations of c and q. It is noticed that the standard deviations normalized by their friction concentrations show very similar stability dependence: σc/|c*|=3.0(1-7.0ζ)-1/3 and σq/|q*|=2.9(1-7.0ζ)-1/3 under unstable conditions, and σc/|c*|=3.0(1+7.0ζ)1/3 and σq/|q*|=2.9(1+7.0ζ)1/3 under stable conditions. This results in the situation that the correlation coefficient between c and q can be expressed as the ratio of 2.9/3.0≈1, where numerals of 3.0 and 2.9 are the value of the normalized standard deviation of c and q under neutral conditions.