Utilizing experimental data of the atmospheric surface layer in the Gobi Oasis of Jinta in a comparative study, we demonstrate that under the condition of unstable stratification, the normalization variances of temper...Utilizing experimental data of the atmospheric surface layer in the Gobi Oasis of Jinta in a comparative study, we demonstrate that under the condition of unstable stratification, the normalization variances of temperature in the oasis and Gobi Desert meet 1/3(z/Λ)(z/Λ)while normalization variances of both humidity and CO2 in the oasis meet(z)sz\Λ-1/3;s s z Λ the normalization variance of temperature in the oasis is large due to disturbance by advection, whereas variance of CO2 in the Gobi Desert has certain degree of deviation relative to Monin-Obukhov(M-O) scaling, and humidity variance completely deviates from variance M-O scaling. The above result indicates that under the condition of advection, humidity variance meets the relationsm sA sB D and it is determined by relative magnitude of scalar variance of advection transport. Our study reveals that, if the scalar variance of humidity or CO2 transported by advection is much larger than local scalar variance, observation value of scalar variance will deviate from M-O scaling; when scalar variance of advection transport is close to or less than local scalar variance, the observation value of scalar variance approximately meets M-O scaling.展开更多
According to the cross coupling theorem of atmospheric turbulence, latent heat flux comprises two components, a vertical humidity gradient flux and a coupling flux of vertical velocity. In this paper, observational da...According to the cross coupling theorem of atmospheric turbulence, latent heat flux comprises two components, a vertical humidity gradient flux and a coupling flux of vertical velocity. In this paper, observational data are employed to demonstrate and analyze the coupling effect of vertical velocity on latent heat flux. The results highlight the presence of a coupling zero-effect height. When the observational level exceeds or underlies the coupling zero-effect height, the coupling effect suppresses or enhances the latent heat flux, respectively. Above the heterogeneous terrain in the experimental region, the overall difference between the estimated and the observed latent heat fluxes decreases from 27% to 2% (for ascending flow) and from 47% to 28% (for descending flow), after compensating for gradient flux. The coupling theorem of atmospheric turbulence is well validated by our analysis, supporting a role for experimental datasets in unraveling the mysteries of atmospheric turbulence.展开更多
基金supported by the National Basic Research Program of China (Grant No.2010CB951701-2)the National Natural Science Foundation of China (Grant Nos. 91025011, 41130961)the Pingliang Station of Lightning and Hail Research, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences
文摘Utilizing experimental data of the atmospheric surface layer in the Gobi Oasis of Jinta in a comparative study, we demonstrate that under the condition of unstable stratification, the normalization variances of temperature in the oasis and Gobi Desert meet 1/3(z/Λ)(z/Λ)while normalization variances of both humidity and CO2 in the oasis meet(z)sz\Λ-1/3;s s z Λ the normalization variance of temperature in the oasis is large due to disturbance by advection, whereas variance of CO2 in the Gobi Desert has certain degree of deviation relative to Monin-Obukhov(M-O) scaling, and humidity variance completely deviates from variance M-O scaling. The above result indicates that under the condition of advection, humidity variance meets the relationsm sA sB D and it is determined by relative magnitude of scalar variance of advection transport. Our study reveals that, if the scalar variance of humidity or CO2 transported by advection is much larger than local scalar variance, observation value of scalar variance will deviate from M-O scaling; when scalar variance of advection transport is close to or less than local scalar variance, the observation value of scalar variance approximately meets M-O scaling.
基金supported by National Natural Science Foundation of China(Grant Nos. 40705007, 1141130961 & 91025011)the Hundred-Talent Project of Chinese Academy of Sciences granted to Dr. YU.
文摘According to the cross coupling theorem of atmospheric turbulence, latent heat flux comprises two components, a vertical humidity gradient flux and a coupling flux of vertical velocity. In this paper, observational data are employed to demonstrate and analyze the coupling effect of vertical velocity on latent heat flux. The results highlight the presence of a coupling zero-effect height. When the observational level exceeds or underlies the coupling zero-effect height, the coupling effect suppresses or enhances the latent heat flux, respectively. Above the heterogeneous terrain in the experimental region, the overall difference between the estimated and the observed latent heat fluxes decreases from 27% to 2% (for ascending flow) and from 47% to 28% (for descending flow), after compensating for gradient flux. The coupling theorem of atmospheric turbulence is well validated by our analysis, supporting a role for experimental datasets in unraveling the mysteries of atmospheric turbulence.