| Title | Characteristics of the turbulence intermittency and its influence on the turbulent transport in the semi -arid region of the Loess Plateau |
| Authors | Wei, Zhuorui Zhang, Lei Ren, Yan Wei, Wei Zhang, Hongsheng Cai, Xuhui Song, Yu Kang, Ling |
| Affiliation | Peking Univ, Sch Phys, Dept Atmospher & Ocean Sci, Lab Climate & Ocean Atmosphere Studies, Beijing 100871, Peoples R China Lanzhou Univ, Coll Atmospher Sci, Minist Educ, Key Lab Semiarid Climate Change, Lanzhou 730000, Peoples R China Chinese Acad Meteorol Sci, State Key Lab Severe Weather, Beijing 100871, Peoples R China Peking Univ, Dept Environm Sci, State Key Joint Lab Environm Simulat & Pollut Con, Beijing 100871, Peoples R China |
| Keywords | NOCTURNAL BOUNDARY-LAYER EMPIRICAL MODE DECOMPOSITION HEAVY HAZE POLLUTION CARBON-DIOXIDE WIND-SPEED SIMILARITY CHINA SCALE MICROFRONTS DISPERSION |
| Issue Date | Feb-2021 |
| Publisher | ATMOSPHERIC RESEARCH |
| Abstract | In this study, observational data from the Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) in July 2008 were used to analyze the characteristics of the turbulence intermittency and its influence on the land-atmosphere turbulent transport over the complex terrain of the semi-arid region of the Loess Plateau in summer. Using the Hilbert-Huang transform (HHT), the local intermittent strength of turbulence (LIST) was calculated based on pure dynamics through an automated algorithm to characterize the turbulence intermittency in this region. But LIST misjudged the actual turbulence intermittency under the condition of weak wind and strong radiation. The thermal effects cannot be ignored in this situation and a thermodynamic intermittency correction factor LISTThermal is suggested to modify LIST. Then a new intermittent strength index LISTReviseis proposed, which is assumed to be the weighted average of LIST and LISTThermal according to the stability parameter z/L. LIST (LISTThermal) is closely related to the near-surface wind-speed (sensible heat flux). Most misjudgments of LIST to turbulence intermittency are corrected, and LISTRevise is more consistent with the general diurnal variation of turbulence intermittency. There are overestimations in turbulent standard deviations and fluxes calculated by conventional eddy covariance (EC) method due to sub-mesoscale motions and turbulence intermittency, producing inaccurate quantifications of turbulent mixing and transport in the planetary boundary layer parameterization schemes. After eliminating the influence of it, the relationship between the normalized standard deviations of different meteorological variables and z/L is more consistent with the Monin-Obukhov similarity rule under stable and unstable stratification. |
| URI | http://hdl.handle.net/20.500.11897/601902 |
| ISSN | 0169-8095 |
| DOI | 10.1016/j.atmosres.2020.105312 |
| Indexed | EI SCI(E) |
| Appears in Collections: | 物理学院 环境科学与工程学院 环境模拟与污染控制国家重点联合实验室 |
