A determination of the Dalton and Stanton numbers over a saturated barley field

In order to determine the values of the Dalton and the Stanton numbers, an observational study was made over a saturated barley field in the Hachirogata. flat reclaimed land located in the northern part of Japan. The mean height of the barley was about 11 cm; the roughness height for momentum was determined from the mean wind profiles as 4.24 ± 0.18 cm and the zero-plane displacement height as 0 cm. Under neutral stratification and a saturated surface, the reciprocals of the Dalton and Stanton numbers, Da^-1 and St^-1, were estimated. The results show that the mean value of St^-1 is 12.1, and the ratio of the bulk transfer coefficient for heat to that for momentum. C_H/C_M, is 0.53, which are not entirely incompatible with the few results available from past observations. The mean value of Da^- is 38.2. This value is larger than St^-1, and fits reasonably well with the semi-empirical equation proposed by Brutsaert (1975a,b).