Variations in Wave Energy and Amplitudes along the Energy Dispersion Paths of Nonstationary Barotropic Rossby Waves  

作　　者：Yaokun LI Jiping CHAO Yanyan KANG 

机构地区：[1]College of Global Change and Earth System Science,Beijing Normal University,Beijing 100875,China [2]National Marine Environmental Forecasting Center,Beijing 100081,China [3]Beijing Meteorological Observatory,Beijing 100089,China

出　　处：《Advances in Atmospheric Sciences》2021年第1期49-64,共16页大气科学进展（英文版）

基　　金：This study was jointly funded by the National Natural Science Foundation of China(Grant Nos.41505042 and 41805041);the National Program on Global Change and Air−Sea Interaction(Grant No.GASI-IPOVAI-03);the National Basic Research Program of China(Grant Nos.2015CB953601 and 2014CB953903);the Fundamental Research Funds for the Central Universities.

摘　　要：The variations in the wave energy and the amplitude along the energy dispersion paths of the barotropic Rossby waves in zonally symmetric basic flow are studied by solving the wave energy equation,which expresses that the wave energy variability is determined by the divergence of the group velocity and the energy budget from the basic flow.The results suggest that both the wave energy and the amplitude of a leading wave increase significantly in the propagating region that is located south of the jet axis and enclosed by a southern critical line and a northern turning latitude.The leading wave gains the barotropic energy from the basic flow by eddy activities.The amplitude continuously climbs up a peak at the turning latitude due to increasing wave energy and enlarging horizontal scale(shrinking total wavenumber).Both the wave energy and the amplitude eventually decrease when the trailing wave continuously approaches southward to the critical line.The trailing wave decays and its energy is continuously absorbed by the basic flow.Furthermore,both the wave energy and the amplitude oscillate with a limited range in the propagating region that is located near the jet axis and enclosed by two turning latitudes.Both the leading and trailing waves neither develop nor decay significantly.The jet works as a waveguide to allow the waves to propagate a long distance.

关 键 词：barotropic Rossby waves energy dispersion wave ray theory wave energy AMPLITUDE 

分 类 号：P43[天文地球—大气科学及气象学]