Observation and Modeling of Satellite-Sensed Meanders and Eddies off Vancouver Island

Abstract

Dep. Oceanogr., Univ. British Columbia, Vancouver, B.C., V6T 1W5, Canada J (Journal-Article) M (Marine) A long time series of satellite infrared images spanning the period 21 July-8 October 1980 reveals the evolution of long (160 km) and short (80 km) wavelength meanders of the California Current System off Vancouver Island. Midway in the series, strong interactions occurred between the two meander scales. Although the shorter meanders were initially more energetic, they were eventually dominated by the longer meanders. Near the end of the time series, detached mesoscale eddies were formed from the longer meanders. Current meter data from the period before meander growth clearly indicates the presence of a strong vertical shear near 150 m, which consists of a southeastward surface current and a northwestward undercurrent. It is argued in this paper that the observed shear flow is the energy source for the meanders and eddies seen in ...