loading page

Revisiting Mesoscale Eddy Zonal Propagation: Addressing the Long-Wave Approximation Limitation for Improved Global Estimates
  • +2
  • Ran Liu,
  • Yan Wang,
  • Xiaoming Zhai,
  • Dhruv Balwada,
  • Julian Mak
Ran Liu
The Hong Kong University of Science and Technology
Author Profile
Yan Wang
The Hong Kong University of Science and Technology

Corresponding Author:[email protected]

Author Profile
Xiaoming Zhai
University of East Anglia
Author Profile
Dhruv Balwada
Columbia University
Author Profile
Julian Mak
HKUST
Author Profile

Abstract

Mesoscale eddies play a crucial role in the transport and mixing processes of the global ocean. Their zonal propagation has routinely been predicted using the theoretical phase speed of long baroclinic Rossby waves. However, this long-wave speed is known to be too fast to quantify the eddy zonal propagation equatorward of ~35 latitudes. To address this fundamental issue, this study takes the local eddy wavelengths into account for estimating the eddy zonal propagation globally, whose accuracy is then significantly improved, particularly across mid- to low-latitudes. This improvement hinges upon the observation that mesoscale eddies across mid- to low-latitudes have length scales comparable to the local deformation scales and do not satisfy the long-wave approximation. Additionally, the observed eddy radii from satellite altimetry can be readily used to estimate the local eddy wavelengths. These findings have significant implications for long-range mesoscale eddy propagation behaviors and eddy-driven mixing throughout the global ocean.
07 Aug 2024Submitted to ESS Open Archive
08 Aug 2024Published in ESS Open Archive