A Method for Separation and Extraction of Ocean First Mode Rossby Wave Signal

Abstract

The invention discloses that the invention relates to a Rossby wave signal separation and extraction technology and algorithm of the ocean's first baroclinic mode. The algorithm is based on the fusion product of altimeter satellite sea surface height anomaly data from 2016 to 2019 and the altimeter vortex identification algorithm, and is based on a series of 2D-FIR filters designed theoretically. The invention confirms the true existence of the Rossby wave in the ocean, and realizes the quantitative evaluation of the proportion of the real Rossby wave signal in each ocean by introducing the initial vortex field signal. It is found that the dominant wave signal in the ocean is the two-year and annual cycle Rossby wave signal, which is most prominent in the Pacific Ocean (up to 25% in mid-latitude), the Indian Ocean has the most significant annual cycle Rossby wave signal, and the Rossby variable wave signal in the Atlantic Ocean is relatively weaker. This invention realizes the quantitative evaluation of ocean Rossby wave energy for the first time, which can provide data reference for updating ocean numerical models, and contribute to the promotion of sea-atmosphere interaction and climate change research.

Description

technical field [0001] The invention relates to the technical field of physical ocean monitoring and analysis, in particular to a method for separating and extracting Rossby wave signals in the first marine mode. Background technique [0002] Oceanic Rossby waves and mesoscale eddies, as the two main manifestations of ocean response to atmospheric driving, play a crucial role in the momentum balance and material circulation of the global ocean. The eddies have prominent ocean current characteristics. In the horizontal direction, it presents an annular structure with closed streamlines, and the flow velocity is one to two orders of magnitude larger than that of the background circulation in the ocean; in the vertical direction, the cyclonic and anticyclonic eddies correspond to the thermocline The upwelling and downwelling generated by the uplift and depression are also one to two orders of magnitude larger than the vertical velocity of the background circulation. The time ...

AI Technical Summary

Problems solved by technology

However, limited by the low spatio-temporal resolution of the single-point sampling mode of contemporary satellite altimeters, co-propagating eddies can be displayed as wave-like structures in the sea level anomaly (SLA) field

Based on potential vortex conservation, vortices and Rossby waves have similar intrinsic westward propagation speeds, so vortices can also be disguised as Rossby waves in low-resolution altimetry data fields, which seriously hinders the clear extraction of oceanic Rossby waves , making the signal separation of oceanic Rossby and mesoscale eddies a century-old problem

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