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Freshwater transport in the East Greenland Current in a realistic, high-resolution Model

MASTER’S THESIS IN PHYSICAL OCEANOGRAPHY

Eirik Kvamme

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Iceland Greenland Seas Project model run

Simulates one year (2017-09-01 to 2018-08-31)

Coupled ocean-ice model

6hourly time resolution saved

Up to 216 vertical layers

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34 psu

Mean horizontal Velocity at Z=50 m

Z= 11.5 m

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NJMR = Northern Jan Mayen Ridge

 

Feb

Aug

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Motivation

Hypotheses

Zonal FWT is dominated by eddy transport

JMC is purely eddy driven or IGP model run does not resolve JMC

Signs of Eddies being important in liquid FWT (Spall et al. 2023)

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Research question

DOES EDDIES TRANSPORT A SIGNIFICANT AMOUNT OF FW FROM THE GREENLAND SHELF INTO THE GREENLAND SEA?

IS JMC PURELY EDDY DRIVEN OR DOES THE MODEL FAIL TO RESOLVE JMC?

WHY DOES LARGE EDDY STRUCTURES FORM AT THE NJMR?

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Where is freshwater transported through the EGC?

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JMC

EGCC/EGC

NIIC

EIC

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EGSB = East Greenland Shelf Break

EIC

NIIC/(EIC?)

JMC

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?

?

Signs of eddy structures

?

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Eddy detection and tracking (WIP)

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Eddy detection

WIP

Local max/min SSH in 9x9 star search pattern

 

Area of outermost closed SSH contour

Method based on Yi et al. 2014; Matsuoka et al. 2016

Overlapping in time

 

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Anti-cyclonic

Cyclonic

Outer region

 

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Conclusions

Questions/feedback?

 

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Defining reference salinity

Method of Aagaard and Carmack 1989

Computed from weighted grid size

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Reference salinity from weighted monthly mean values

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How does the model results differ from observations?

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Model - observed

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Volume transport at boundaries

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Mean volume transport

Cumulated mean volume transport

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Mean volume transport

Cumulated mean volume transport

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Advective

Surface forcings

 

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Eddy method

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Ongoing

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Eddy duration

Unique ID’s: 7 494

Total eddies: 25 377

Anti-cyclonic

Cyclonic

Total

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All eddies

 

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