Topographically Trapped Waves Around South America With Periods Between 40 and 130 Days in a Global Ocean Reanalysis

The South American continental slope hosts a variety of topographic waves. We use 27-year-long global ocean reanalysis (1/12° Spatial resolution) to examine trapped waves (TWs) around America at periods ranging from 40 130 days. propagate the Equatorial Pacific Tropical Atlantic (22°S) with phase velocities between 1.8 and 7 m/s according local background characteristics, such as stratification, steepness, latitude, mean flow shelf width. Madden-Julian Oscillation (MJO) plays key role in forcing TWs two ways (a) through an oceanic connection implying equatorial Kelvin reaching western Coast (b) atmospheric teleconnection enhancing southerly winds south-east Pacific. Furthermore, winds, not necessarily linked MJO, modulate trigger specific locations, Brazil-Malvinas Confluence. Trapped impact along-shore currents: during positive near-surface is enhanced by about 0.1 m/s.