Current Retroflection from a Slanted Coastline

Recent proxies suggest that, at the end of the last
glacial, there was a significant increase in the
injection of Agulhas rings into the South Atlantic.
This event brought about a dramatic increase in the
salt influx helping to re-start the Atlantic
meridional overturning circulation. Until now the
mechanism through which such large variation in ring
production occurs has not been clear. In this book,
two semi-analytical non-linear models of current
retroflection from non-zonal coastline on the -plane
are developed to explain this phenomenon. The
critical value of the coastline slant is defined,
which implies restricted possibilities for ring
detachment from the retroflection area in the supercritical range of . In the case of Agulhas
region, rings can be injected only if the
retroflection occurs beyond specific latitude where
the angle is critical. This analysis should help in
understanding the regimes of ring shedding by
retroflected currents and should be useful for anyone
studying the dynamics of currents, meridional
overturning cell in the Atlantic and climate dynamics.

Autorentext

Volodymyr Zharkov, Ph.D.: Post-Doctoral Research Associate atGeophysical Fluid Dynamics Institute, Florida State University,Tallahassee, U.S.A.

Klappentext

Recent proxies suggest that, at the end of the lastglacial, there was a significant increase in theinjection of Agulhas rings into the South Atlantic.This event brought about a dramatic increase in thesalt influx helping to re-start the Atlanticmeridional overturning circulation. Until now themechanism through which such large variation in ringproduction occurs has not been clear. In this book,two semi-analytical non-linear models of currentretroflection from non-zonal coastline on the ß-planeare developed to explain this phenomenon. Thecritical value of the coastline slant is defined,which implies restricted possibilities for ringdetachment from the retroflection area in the'supercritical' range of . In the case of Agulhasregion, rings can be injected only if theretroflection occurs beyond specific latitude wherethe angle is critical. This analysis should help inunderstanding the regimes of ring shedding byretroflected currents and should be useful for anyonestudying the dynamics of currents, meridionaloverturning cell in the Atlantic and climate dynamics.