Transcript zakrzewski bridget sol 2014 sm

Eddy-fying Research: Understanding
Properties of Southern Ocean Eddies
Intern: Bridget Zakrzewski
Mentor: Ivy Frenger
How can we combine surface and sub-surface
data to observe mesoscale eddies?
What Is An Eddy?
• Whirlpools
• Part of ocean turbulence
• Importance:
- Mixing and water-mass transport
- Tracer distribution & ocean dynamics
(Southern Hemisphere)
Drake Passage Eddy, NASA
How Can We Observe Eddies?
• Altimetry (AVISO – 1992)
(spatio-temporal coverage, no sub-surface data)
• In-Situ Data (Argo – early 2000s)
(Vertical structure, less spatio-temporal coverage)
• Both
(get the benefits of each!)
ACC Eddies
• Antarctic Circumpolar Current (ACC) surrounds
Antarctica
• ACC is largest current in the world
• Southern Ocean dynamics
South ACC
North ACC
North ACC
North ACC
Eddy anomalies shown above. Note: North of ACC = outside of ACC, South of ACC = inside of ACC
Eddies near South Western Australia
(or “Weird” Eddies)
• Cyclones with positive anomaly
• Maximum life span of 72+ weeks
(Courtesy of Ivy Frenger)
“Weird” Eddy Anomalies (3+ months)
(Sorted by eddy lifespan)
Bin1: <22wks
Bin2: 22-31wks
Bin3: 32-41wks
Bin4: 42-51wks
Bin5: 52-61wks
Bin6: 62-71wks
Bin7: 72-81wks
Bin8: >82wks
Possible Origins of “Weird” Eddies
• Warm surface boundary currents
• Eddy-rich currents
Potential Future Research
• Take a closer look at salinity anomaly
crossing
• Observe eddies near other boundary
currents
• Use absolute values, not anomalies
• Understand differences in slopes for
anticyclones vs. cyclones
Acknowledgements
For the continuous support throughout my summer
experience, I would like to thank:
Ivy Frenger, Mentor
Professor Jorge Sarmiento, Host
AOS/GFDL community, Support
Princeton Environment Institute (PEI)