全球海洋高频波动主振荡周期的纬向带状分布特征
The zonal distribution features of high frequency oscillations in the oceans derived from satellite altimeter data
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摘要: 基于1992年10月至2000年12月的TOPEX/Poseidon和ERS-1/2卫星高度计资料,分析了周期短于150d的高频波动及其能量的空间分布特征.在功率谱密度计算基础上,分析特定频段所含能量占周期短于150d的高濒波动总能量的百分比,发现该频段最强振荡(下文称主振荡)所对应的周期从近赤道的1个月逐步增加至南北纬30°附近的4个月,进一步分析表明主振荡周期的这种变化是连续的,与西向行星Rossby波的相速随纬度增加而变慢相对应.主振荡所对应的周期在全球海洋中呈显著的带状分布.进而表明在14°N(S)附近60d周期的振荡除通常所认为的由于潮汐混淆所造成的虚假信号之外,主要是行星Rossby波形态的真实信号.Abstract: Based on TOPEX/Poseidon(T/P) and ERS-1 and 2 satellite altimeter data between October 1992 and December 2000,high frequency oscillations with periods less than 150 d are analyzed and their spatial distributions are described.The ratio,instead of the energy itself,of the energy corresponding to certain frequency band from power spectrum relative to the total energy in the 20~143 d range is analyzed.The results show that the period of the most energetic oscillations in this band continuously increases with latitude fr om about 1 month near the tropics to about 4 months near 30b,in agreement with the latitudinal dependency of the phase speed of westward propagating Rossby waves,which dominate the variability in those latitudes.As a result,the global spatial distributions of the period of the dominant oscillations are largely zonal,with relatively small differences between different ocean basins.It suggests that the oscillations with periods around 60 d are mainly associated with Rossby waves except being often regarded as tidal aliasing.
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DUCET N,LE P Y. Traon global high-resolution mapping of ocean circulation from TOPEX/Poseidon and ERS-1 and-2 [J].J Geophy Res,2000,105:19 477-19 498. CHELTON D B,SCHLAX M G. Global observations of oceanic Rossby waves[J].Science,1996,272:234-238. KILLWORTH P D,CHELTON D B,SZOEKE R A. The speed of observed and theoretical long extratropical planetary waves[J].J Phys Oceanogr,1997,24:1 946-1 966. WHITE M A,HEYWOOD K J. Seasonal and interannual changes in the North Atlantic subpolar gyre from Geosat and TOPEX/Poseidon altimetry[J].J Geophys Res,1995,100:24 931-24 954. BOULAGER J P,MENKES C. Propagation and reflection of long equatorial waves in the Pacific Ocean during the 1992~1993 El Nino[J].J Geophys Res,1995,100:25 041-25 060. GIPOLLINI P,GROMWELL D,JONES M S,et al. Concurrent altimeter and infrared observations of Rossby wave propagation near 34°in the Northeast Atlantic[J].Geophys Res Lett,1997,24:889-892. LIL,XUJD,CAIRS. Trends of sea level risein the South China Sea during the 1990s:an altimetry result[J].Chinese Science Bulletin,2002,47(7):582-585. WUNSCH C. Global-scale sea surface variability from combined altimetric and tide gauge measurements[J].J Geopgys Res,1991,96:15 053-15 082. WUNSCH C,STAMMER D. The global frequency-wavenumber spectrum of oceanic variability estimated from TOPEX/Poseidon altimetric measurements[J].J Geophys Res,1995,100:24 895-24 910. FU L-L,CHENG B,QIU B. 25-day period large-scale oscillation in the Argentine basin revealed by the TOPEX/Poseidon altimeter[J].J Phys Oceanogr,2001,31:506-517. McPHADEN M J. Monthly period oscillations in the Pacific north equatorial countercurrent[J].J Geophys Res,1996,101:6 337-6 359. 刘秦玉,王启.热带太平洋海平面高度季节内振荡的空间分布特征[J].青岛海洋大学学报,1999,29(4):549-555. KURAGANO T,KAMACHI M. Global statistical space-time scales of oceanic variability estimated from the TOPEX/Poseidon altimeter data[J].J Geophys Res,2000,105:955-974. STAMMER D. Global characteristics of ocean variability estimated from regional TOPEX/POSEIDON altimeter measurements height data[J].J Phys Oceanogr,1997,27:1 743-1 769. SCHLAX M G,CHELTON D B. Aliased tidal errors in TOPEX/Poseidon sea surface height data[J].J Geophy Res,1994,99:24 761-24 776. ZANG X Y,WUNSCH C. Spectral description of low-frequency oceanic variability[J].J Phys Oceanogr,2001,31(10):3 073-3 095. YU Z,McCREARY J P,PROEHL J A. Meridional asymmetry and energetics of tropical instability waves[J].J Phys Oceanogr,1995,25:2 997-3 007.
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