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The Interaction of Anticyclonic Eddies with
Deep Convection
Fiammetta Straneo (WHOI), Jonathan Lilly (ESR),
T. Rykova (MIT/WHOI)
An increasing
amount of observational evidence now points to intense, often
long-lived, anticyclonic eddies as one of the outstanding
dynamical features in the deeply convecting regions of the
world ocean. Yet modeling studies, informed by the more
limited observations available in the past, have tended to
focus on precisely the opposite case, cyclonic eddies that
rapidly disintegrate when subjected to strong surface cooling.
Anticyclonic eddies could interact with deep convection in a
variety of ways, but their net effect on convective water mass
transformation is far from obvious; their influence must
therefore be considered an important unresolved element of the
global thermohaline circulation. We propose to investigate the
interaction between anticyclonic eddies and convection using a
combined modeling and data analysis approach. Through an
hierarchy of numerical models, we will examine the detailed
behavior of anticyclonic eddies subject to strong surface
buoyancy loss throughout a broad range of parameter space.
With the aid of newly-developed mathematical and statistical
techniques, we will systematically identify and describe
coherent eddies in several key convection areas using a
variety of high-quality datasets. The net result should be a
significant step towards a more complete understanding of deep
convection in a realistic setting.

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Anticyclonic eddies observed from a mooring in the
central Labrador Sea - temperature is shaded and velocity
is overlaid in white. Left: anticylonic lense containing
recently convected water (formed by convection). Right:
Warm, salty anticyclone of boundary current origin.
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Presentations and Posters
Seasonal
and Interannual Variability of the West Greenland Current
System in 1992-2008, T.
Rykova, F. Straneo, A. Bower,
AGU
Ocean Sciences 2010, Poster.
Did
the Great Salinity Anomaly really prevent deep convection in
the Labrador Sea from 1968 to 1971 ? R.
Gelderloos,
F. Straneo, and C. A. Katsman, EGU Meeting, Vienna, 2010,
Poster.
Why
are the densest waters in the North Atlantic formed in the
Nordic Seas? F.Straneo, Session in honour of F. Schott,
EGU Meeting, Vienna, April 2009, Presentation.
Impact
of a barotropic boundary current on eddies in a convective
basin. Deshayes,J.,M.Spall and F.Straneo, Clivar Workshop
on Mesoscale Eddies, Exeter, April, 2009, Poster.
Irminger
Current Anticyclones in the Labrador Sea Observed in the
Hydrographic Record, 1990-2004. Rykova,T.,F.Straneo, J.
Lilly and I. Yashayaev, Ocean Science 2008 Presentation.
On
the effect of a sill on dense water formation in a marginal
sea. Iovino,D., F.Straneo, M. Spall, Ocean ScienceS 2008
Poster.
Why
are the densest waters in the North Atlantic formed in the
Nordic Seas? Straneo, F., AGU Ocean Sciences 2008
Presentation.
Analysis
of Irminger Anticyclones from Hydrographic Data (Rykova
Master of Science Thesis).
Contribution
of Warm Salty Anticyclones to the Convection in the Labrador
Sea. Rykova and Straneo, AGU Ocean Sciences, 2006,
Poster.
Papers
Irminger
Current Anticyclones in the Labrador Sea Observed in the
Hydrographic Record, 1990-2004. Rykova,T.,F.Straneo, J.
Lilly and I. Yashayaev, J. Mar. Res., 67, 361-384.
Mechanisms
of variability in a convective basin. Deshayes,J.,
F.Straneo, M. Spall, J. Mar. Res. (67), 273-303.
On
the effect of a sill on dense water formation in a marginal
sea. Iovino,D., F.Straneo, M. Spall, J. Mar. Res. 66,
325-345.
Lilly, J.M.
and J.C. Gascard, 2006. Wavelet ridge diagnosis of
time-varying elliptical signals with application to an
oceanic eddy Nonlin. Processes
Geophys.,13, 467— 483.
This
project is supported by the National Science Foundation Ocean
Sciences Division.
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