Equatorial Kelvin waves are geostrophically balanced, eastward-propagating disturbances whose pressure/height and horizontal wind perturbations are symmetric about and trapped near the equator, distinguishing them from the antisymmetric (across the equator) structure of Rossby and mixed Rossby-gravity waves.
The depicted low (L) and high (H) pressure/height perturbation cells are centered directly on the equator with symmetric circulation patterns flanking each cell, consistent with...
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