Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The ...Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The observations were corrected by employing wild point rejection,linear detrending,delay correction,coordinate rotation,time matching,and Webb,Pearman,and Leuning(WPL)correction.The results of spectral analysis and a turbulence development adequacy data quality check showed that the overall observation data quality was good.The air-sea water vapor and CO_(2) flux results showed that the observation duration affected both the air-sea flux intensity and direction at different observation frequencies.At shorter observation durations,the air-sea flux values measured at 100 Hz were smaller than the 20 Hz measurements and had opposite directions.In addition,the WPL correction reduced the overall air-sea flux and partially minimized the effect of observation frequency on the air-sea flux intensity.These results showed that high-frequency observations showed more turbulence variations than low-frequency observations.This conclusion could promote an understanding of small-scale turbulence variations.展开更多
Based on CAMP/Tibet [Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan Plateau] turbulent data collected at the Bujiao (B J) site of the Nagqu area, the turbulent ...Based on CAMP/Tibet [Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan Plateau] turbulent data collected at the Bujiao (B J) site of the Nagqu area, the turbulent structure and transportation characteristics in the near surface layer during summer are analyzed. The main results show that the relationship between the normalized standard deviation of 3D wind speed and stability satisfies the similarity law under both unstable and stable stratifications. The relations of normalized standard deviation of temperature and specific humidity to stability only obey the "-1/3 power law" under unstable conditions. In the case of stable stratifications, their relations to stability are dispersing. The sensible heat dominates in the dry period, while in the wet period, the latent heat is larger than the sensible heat.展开更多
A flux system deployed on a moored buoy has been described, which is capable of directly estimating the airsea fluxes after removing the contamination in the signal due to buoy motion. A triple loop fitting method has...A flux system deployed on a moored buoy has been described, which is capable of directly estimating the airsea fluxes after removing the contamination in the signal due to buoy motion. A triple loop fitting method has been demonstrated for determining the three angular offsets between measurement axes of the sonic anemometer and motion pack. The data collected in an experiment in the Northern Huanghai Sea is used to correct the three sonic anemometer measurements of turbulent wind for buoy motion. The effective removal of wave-scale motion from the spectra and cospectra are demonstrated. Estimates of along-wind momentum flux, sensible heat flux and latent heat flux calculated by the eddy correlation method based on data obtained by sonic anemometer 81000V are shown to be in the same trend and scale with those determined by the bulk aerodynamic method after motion correction. The motion correction not only greatly improve the estimation of the momentum flux but also has a great impact on the calculated sensible heat flux.展开更多
基金The National Key Research and Development Program of China under contract Nos 2022YFC3104203 and 2018YFC0213103the Science Foundation of Donghai Laboratory under contract No.DH-2022KF01019+1 种基金the National Natural Science Foundation under contract No.419061522023 Shanghai Education Science Research Project under contract No.C2023120.
文摘Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The observations were corrected by employing wild point rejection,linear detrending,delay correction,coordinate rotation,time matching,and Webb,Pearman,and Leuning(WPL)correction.The results of spectral analysis and a turbulence development adequacy data quality check showed that the overall observation data quality was good.The air-sea water vapor and CO_(2) flux results showed that the observation duration affected both the air-sea flux intensity and direction at different observation frequencies.At shorter observation durations,the air-sea flux values measured at 100 Hz were smaller than the 20 Hz measurements and had opposite directions.In addition,the WPL correction reduced the overall air-sea flux and partially minimized the effect of observation frequency on the air-sea flux intensity.These results showed that high-frequency observations showed more turbulence variations than low-frequency observations.This conclusion could promote an understanding of small-scale turbulence variations.
基金This research was supported by the Innovation Project of the Chinese Academy of Sciences (KZCX3-SW-339 and KZCX3-SW-329) the National Natural Science Foundation of China (Grant No. 40520140126).
文摘Based on CAMP/Tibet [Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan Plateau] turbulent data collected at the Bujiao (B J) site of the Nagqu area, the turbulent structure and transportation characteristics in the near surface layer during summer are analyzed. The main results show that the relationship between the normalized standard deviation of 3D wind speed and stability satisfies the similarity law under both unstable and stable stratifications. The relations of normalized standard deviation of temperature and specific humidity to stability only obey the "-1/3 power law" under unstable conditions. In the case of stable stratifications, their relations to stability are dispersing. The sensible heat dominates in the dry period, while in the wet period, the latent heat is larger than the sensible heat.
基金The National Basic Research Program of China under contract No. 2011CB403501the Fund for Creative Research Groups by NSFC of China under contract No. 40821004+1 种基金the Knowledge Innovation Programs of the Chinese Academy of Sciences under contract No. KZCX2-YW-Q07-02the High-Tech Research and Development Program (863 Program) of China under contract No. 2006AA09A309
文摘A flux system deployed on a moored buoy has been described, which is capable of directly estimating the airsea fluxes after removing the contamination in the signal due to buoy motion. A triple loop fitting method has been demonstrated for determining the three angular offsets between measurement axes of the sonic anemometer and motion pack. The data collected in an experiment in the Northern Huanghai Sea is used to correct the three sonic anemometer measurements of turbulent wind for buoy motion. The effective removal of wave-scale motion from the spectra and cospectra are demonstrated. Estimates of along-wind momentum flux, sensible heat flux and latent heat flux calculated by the eddy correlation method based on data obtained by sonic anemometer 81000V are shown to be in the same trend and scale with those determined by the bulk aerodynamic method after motion correction. The motion correction not only greatly improve the estimation of the momentum flux but also has a great impact on the calculated sensible heat flux.