The Equilibrium Range of Wind Wave Spectra: an Explanation Based on White Noise  

作　　者：DAI Dejun WANG Wei QIAO Fangli YUAN Yeli 

机构地区：[1]Key Laboratory of Marine Science and Numerical Modeling, SOA, Qingdao 266061, P. R. China [2]The First Institute of Oceanography, SOA, Qingdao 266061, P. R. China [3]Physical Oceanography Laboratory, Ocean University of China, Qingdao 266003, P R. China

出　　处：《Journal of Ocean University of China》2007年第4期345-348,共4页中国海洋大学学报（英文版）

基　　金：This study was financially supported by the National Natural Science Foundation of China （Grant No. 40406008）;the Foundation for 0pen Projects of the Key Lab of Physical 0ceanography, the Ministry of Education, China （Grant No. 200309）.

摘　　要：Laboratory experiments and field observations show that the equilibrium range of wind wave spectra presents a – 4 power law when it is scaled properly. This feature has been attributed to energy balance in spectral space by many researchers. In this paper we point out that white noise on an oscillation system can also lead to a similar inverse power law in the corresponding displacement spectrum, implying that the – 4 power law for the equilibrium range of wind wave spectra may probably only reflect the randomicity of the wind waves rather than any other dynamical processes in physical space. This explanation may shed light on the mechanism of other physical processes with spectra also showing an inverse power law, such as isotropic turbulence, internal waves, etc.Laboratory experiments and field observations show that the equilibrium range of wind wave spectra presents a -4 power law when it is scaled properly. This feature has been attributed to energy balance in spectral space by many researchers. In this paper we point out that white noise on an oscillation system can also lead to a similar inverse power law in the corresponding displacement spectrum, implying that the -4 power law for the equilibrium range of wind wave spectra may probably only reflect the randomicity of the wind waves rather than any other dynamical processes in physical space. This explanation may shed light on the mechanism of other physical processes with spectra also showing an inverse power law, such as isotropic turbulence, internal waves, etc.

关 键 词：wind wave spectrum equilibrium range -4 power law white noise 

分 类 号：P732[天文地球—海洋科学]