Buoyancy effect on atmospheric surface layer: measurements from the East Coast of Malaysia

15th Asian Congress of Fluid Mechanics

物理学;力学

Harun, Z.^1,2 ; Reda, E.^1 ; Zulkifli, Rozli^1

Dept. Mechanical and Materials, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, UKM Bangi

43600, Malaysia^1

Marine Ecosystem Research Centre (EKOMAR), Faculty of Science and Technology, Universiti Kebangsaan Malaysia, UKM Bangi

43600, Malaysia^2

关键词: Atmospheric surface layers;    Cross correlations;    Ecosystem research;    Stability condition;    Stability parameters;    Turbulence spectrum;    Unstable conditions;    Vertical correlation;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/822/1/012043/pdf
DOI  :  10.1088/1742-6596/822/1/012043

学科分类：力学，机械学

来源: IOP

【 摘 要 】

The nature and evolution of the atmospheric surface layer is still unresolved completely. Many questions regarding the existence of the z-less layer and trend of the cross correlations still remain open. This research analyzes some of the surface layer ambiguities. In this research temperature, velocity and turbulence data were collected from a weather station facility located in the Marine Ecosystem Research Centre (EKOMAR) Mersing on the East Coast of Malaysia. Two high resolution hotwires were utilized at 3 m and 12 m heights above ground. Both gradient Richardson number and Obukhov stability parameter were calculated. Turbulence spectra were plotted at different stability conditions. The results does not show the existence of the z-less layer at deep stable condition. The buoyancy force, under unstable condition, was found responsible for the increase of vertical correlation factor. The fingerprint of the buoyancy force was detected in the spectra at low frequencies.