Multidecadal Intensification of Atlantic Tropical InstabilityWaves

Tuchen, F. P., Perez, R. C., Foltz, G. R., Brandt, P., & Lumpkin, R. (2022). Multidecadal intensification of Atlantic tropical instability waves. Geophysical Research Letters, 49(22), e2022GL101073.

Abstract: In the equatorial Atlantic, temperature, salinity, sea level anomaly, and ocean velocity variations on time scales of tens of days are dominated by the presence and westward passage of large-scale Tropical Instability Waves (TIWs). Several decades of satellite and surface drifter data as well as moored velocity observations show a long-term intensification of TIW activity in all of these variables in the tropical North Atlantic where TIWs are most pronounced. We find that increased high-frequency flow variability, and not long-term changes of the mean zonal current system, drives the TIW intensification. One consequence of increased Atlantic Ocean TIW activity is the corresponding intensification of the horizontal eddy temperature advection pattern in boreal summer leading to stronger cooling of surface waters north of the equator…

Read Full Paper.