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Evolution of the East Greenland Current from

Fram Strait to Denmark Strait: Synoptic

measurements from summer 2012

Lisbeth Håvik

Robert Pickart

Kjetil Våge

Agnieszka Beszczynska-Möller

Waldemar Walczowski

The East Greenland Current

separated EGC

shelfbreak EGC

Data

8 densely sampled

sections across the

EGC (August 2012).

CTD and velocity

measurements.

Lack velocity section 10.

Data

3 sections from

IOPAS cruise

in northeastern

Nordic Seas

(July 2012).

CTD and

velocity

measurements.

Water masses

Kinematic structure

Absolute geostrophic velocities obtained by

referencing geostrophic velocities to the measured

velocities.

Kinematic structure

Shelf break East Greenland Current

Polar Surface Water jet

Outer East Greenland Current

Shelf break East Greenland Current

Shelf break East Greenland Current

Reduced surface transport south of the JMFZ, how

does this affect freshwater transport?

Freshwater transport

Freshwater transport

Separated EGC ~35% of the FWT.

PSW jet ~40 % of the FWT.

Outer EGC

Outer EGC

NwAFC WSC

Outer EGC

Outer EGC

Hypothesis: A direct recirculation of the

Norwegian Atlantic Frontal Current in the Fram

Strait resulted in the outer EGC.

Modification of Atlantic-origin water

Modification of Atlantic-origin water

Modification of Atlantic-origin water

Limited densification of the Atlantic-origin water

in the main core of the current along-stream.

The East Greenland Current system

separated EGC shelfbreak EGC

Summary

Three current cores detected in the EGC system:

• Shelf break EGC – Supply on average 2.2 Sv of

dense Atlantic-origin overflow water to the Denmark

Strait.

• PSW jet – carries ~ 40% of the FWT.

• Outer EGC - direct recirculation of NwAFC in Fram

Strait.

Atlantic-origin Water, and hence overflow water, is not

densified along-stream within the main current.