The Climate Consequences of Ice Sheet Collapse in the Arctic

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The Climate Consequences of Ice Sheet Collapse in
the Arctic

• Clare Jones
• University of Sheffield

Supervisor Prof. Grant Bigg
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Rationale

• Kristoffersen et al., 2004. Seabed erosion on the
  Lomonosov Ridge, central Arctic Ocean A tale of
  deep draft icebergs in the Eurasia Basin and the
  influence of Atlantic water inflow on iceberg
  motion?

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Kristoffersen et al., (2004)

• Floating ice shelves verses deep draft icebergs
• Incomplete erosion of hemipelagic drape
• Topographic control of ice motion
• Iceberg plowmarks

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Kristoffersen et al., (2004)
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Kristoffersen et al., (2004)
Penultimate glaciation (150 kyr ago)
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Aim

• To investigate the impact of large freshwater
• fluxes entering a glacial Arctic in the form of
• giant icebergs

• Stages
• Ocean-only experiment
• Atmosphere, ocean and iceberg coupled
• Including ice sheet dynamics

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Progress so far

• Stage 1
• Ocean model required that has good resolution in
  the Arctic and realistic representation of
  processes in the central Arctic

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FRUGAL(Fine ResolUtion Greenland sea And
Labrador sea Model)

• North Pole located in Greenland
• Model horizontal resolution of 2 ? x 1.5 ? in the
  far field and 0.5 ? or less in the Artic.
• Variable time step length (340-2700 s)

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Model Runs So Far

• Simulating last glacial maximum and present day
• Runs
• 1000 year spin-up
• Adding 2-7 Sv of freshwater at Kara-Barents Sea
  margin for 50-400 years
• Continue simulation for several hundred years

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Preliminary Results

• Present Day
• 1000yr spin up, freshwater added for 100 years,
  model run for a further 100 years

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Preliminary Results
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Future work

• Stages 2 3
• Couple iceberg trajectory model (Bigg et al.,
  1997) with ocean model
• Add coupled model to current fabric of GENIE

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