近地层非平稳条件下地气湍流通量研究进展  

Progress in the Study of Turbulent Fluxes of Ground Gas Under Non-stationary Conditions in the Near-surface Layer

作　　者：吴宇杰 李煜斌[1] WU Yujie;LI Yubin(Nanjing University of Information Science&Technology,Nanjing 210044,China;Henan Institute of Meteorological Science,Zhengzhou 420002,China)

机构地区：[1]南京信息工程大学,江苏南京210044 [2]河南省气象科学研究所,河南郑州420002

出　　处：《地球科学进展》2024年第10期1009-1020,共12页Advances in Earth Science

基　　金：国家重点研发计划项目(编号:2023YFC3706300)资助.

摘　　要：在地表与大气间的物质和能量交换中,湍流发挥着至关重要的作用,它控制着输送给大气的热量,调节着大、中、小尺度运动的动能传递与耗散。当前在近地层中,大气湍流的研究通常被简化为具有均一性的平稳湍流,然而由于下垫面等因素的影响,真实大气中湍流通常会表现出非均一性的非平稳特征。通过对近地层非平稳条件下地气湍流通量的国内外相关研究进行归纳和综述,回顾了近地层非平稳湍流的特征,如间歇性、非对称性和非均一性等。非平稳湍流的出现机理主要为动力因素和热力因素。讨论了湍流时间序列平稳性检验的5种方法,以及目前使用的近地层非平稳湍流通量算法(小波分析法)。发现当前针对非平稳湍流通量的计算还有巨大的进步潜力,其中通过向湍流数据中增加已知非平稳信息从而获取“湍流通量真实值”的方法对后续的非平稳湍流研究提供了新的思路。Turbulence plays a crucial role in the exchange of mass and energy between the surface and the atmosphere,controlling the heat transfers to the atmosphere and regulating the transfer and dissipation of kinetic energy in large-,meso-and micro-scale motions.However,the current study of atmospheric turbulence in the surface layer is usually simplified to stationary turbulence with homogeneity.However,the turbulence in the real atmosphere usually exhibits the non-stationary characteristics of non-homogeneity due to multiple factors(e.g.underlying surface heterogeneity).In this study,we summarize and review the domestic and international research on turbulent flux under non-stationary conditions in the surface layer,and also review the characteristics of non-stationary turbulence(e.g.intermittency,asymmetry,and inhomogeneity).The mechanism behind the emergence of non-stationary turbulence can be attributed to dynamic and thermal factors.This paper discusses five methods for stationarity examination of turbulent time series and the currently used algorithm for nonstationary turbulent fluxes calculation in the near-surface layer(i.e.,wavelet analysis method).It finds that there is significant potential for advancement in current calculations of non-stationary turbulent fluxes.The method of introducing known non-stationary information into turbulent data to obtain the“true value of turbulent flux”offers new insights for future research on non-stationary turbulence.

关 键 词：非均匀下垫面 非平稳湍流 平稳性判定方法 湍流通量计算方法 

分 类 号：P425.2[天文地球—大气科学及气象学]