Ocean Model Development (and relation to ice shelves)

• IPCC summarized top two impacts of physical climate change as (a) air temperature, and (b) sea level• Without any physical model of sea level, IPCC reported a seal level projection• Ocean models could be argued to be relevant to sea level change projections• Ocean modeling has no meaningful plan to address one of IPCC two main’s concerns

Relevance ofIce-Shelf Ocean Interaction

Sea Level Rise (SLR) projection 2100

Changes in SL will have some regional character:past -> ‘fingerprints’polar wanderingself gravityocean dynamic height

Contributions are Steric and Eustatic

Eustatic Component –Role of the Ice Sheets

Main concern is marine portions of Greenland and Antarctica

What’s happening inice shelf – ocean research

Observational programsamong the harshest /difficult environments to sample (ocean beneath kms of ice)

Theoretical developmentsamong the most challenging fluid dynamical behaviors (calving)

Modeling Initiativesrequires major reworking of ocean codes(kms of surface pressure, grounding line migration)

Ice Processes

Ocean Processes –Water Mass Transformation

Ocean Processes –Other Considerations

What have we observed in the last decade or so?

Any big changes?

Yes!

The perimeter of the ice sheets, where they are floating,

and where there exists warm ocean waters is undergoing dramatic change.

Greenland Change:Jakobshavn Isbrae

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Why Change @Jakobshavn Isbrae?

Antarctica Change:Pine Island Glacier (PIG)

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Why Change @Pine Island Glacier?

Some Recent Ocean Observations:Depths and Temperatures at

Jakobshavn, August 2009

Some Future Ocean Observations:2010-2015

Greenland – Modest Ice Tongues Jakobshavn, Helheim(From Boat or Helicopter:CTD, XCTD, Glider, AUV)

Antarctica – Massive Ice ShelvesPIG, WISSARDS

(From Icebreaker or Drilling:Profiling CTD, AUV)

… and now on to ice-shelf – ocean interaction theory and model(l)ing …