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《Global observations of nonlinear mesoscale eddies》

  • 来源专题：物理海洋学知识资源中心
  • 编译者： cancan
  • 发布时间：2018-11-14

  • Chelton, Dudley B.; Schlax, Michael G.; Samelson, Roger M.Global observations of nonlinear mesoscale eddies.

    来源: Progress in Oceanography, 2011, 91(2):167-216

    摘要: Sixteen years of sea-surface height (SSH) fields constructed by merging the measurements from two simultaneously operating altimeters are analyzed to investigate mesoscale variability in the global ocean. The prevalence of coherent mesoscale features (referred to here as “eddies”) with radius scales of O(100 km) is readily apparent in these high-resolution SSH fields. An automated procedure for identifying and tracking mesoscale features based on their SSH signatures yields 35,891 eddies with lifetimes ?16 weeks. These long-lived eddies, comprising approximately 1.15 million individual eddy observations, have an average lifetime of 32 weeks and an average propagation distance of 550 km. Their mean amplitude and a speed-based radius scale as defined by the automated procedure are 8 cm and 90 km, respectively.

    全文网址：https://www.sciencedirect.com/science/article/pii/S0079661111000036

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