Observed Warm Filaments from the Kuroshio Associated with Mesoscale Eddies

Qian Shi,Guihua Wang

doi:10.3390/rs12183090

Abstract

Based on high resolution satellite observations of sea surface temperature (SST), warm filaments near the Kuroshio around the Luzon Strait were systematically identified. These filaments extend an average length of about 200 km from the Kuroshio. The occurrence and features of the warm filaments are highly associated with both mesoscale eddies and the intensity of the SST gradient of the Kuroshio. Warm filaments are formed by heat advection from the warm Kuroshio into the colder interior Pacific Ocean by anticyclonic eddies (∼58%), cyclonic eddies (∼10%), and the dipole eddies (∼16%). The large temperature gradient near the Batanes Islands may also contribute to the high frequency of warm filaments in their vicinity. This study will help elucidate the role of zonal heat transport associated with the Kuroshio–eddy interaction during filament formation.

Highlights

Warm filaments are long, narrow horizontal belts of higher sea surface temperature (SST) than their surroundings, which have been referred to as warm tongues, plumes, and squirts respectively [1]
680 warm filaments from the Kuroshio were identified over the 12 years between 2006–2018
It is interesting to see a similar trend of mesoscale eddies, which indicates a linkage between warm filaments and mesoscale eddies

Summary

Introduction

Narrow horizontal belts of higher sea surface temperature (SST) than their surroundings, which have been referred to as warm tongues, plumes, and squirts respectively [1]. They are typically observed to extend from strong, warm, ocean boundary currents, and are strongly associated with mesoscale eddies that are interacting with the current [2,3]. Modern technologies of remote sensing, including high resolution satellite observations of sea surface temperature and sea level anomalies, make it possible to detect warm filaments and study the underlying mechanisms. Cold filaments are often associated with strong offshore currents, and are found to contribute significantly to cross-shelf material exchange [14]

Results

Discussion

Conclusion