Columbia

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NASA oceanography from satellites to
supercomputers
SeaStar
TRMM
NSCAT
QuikSCAT
TOPEX
Terra
Jason
Seasat
SeaWinds
Columbia
Aqua
Explore
Cosmos
GRACE
Aquarius
ICESat
OSTM
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Ocean carbon cycle
(Sarmiento and Gruber 2002)
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ECCO Estimating the Circulation and Climate of
the Ocean
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Mechanisms of air-sea CO2 flux variability in the
equatorial Pacific and the North
Atlantic (McKinley, Follows, and Marshall, 2004)
Mean CO2 flux (mol/m2/yr)
Hovmoller diagrams of simulated Equatorial
Pacific anomalies
First EOF of air-sea flux of CO2 and of sea
surface temperature
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Carbon isotope evidence for the latitudinal
distribution and wind speed dependence of the
air-sea gas transfer velocity (Krakauer,
Randerson, Primeau, Gruber, and Menemenlis,
submitted)
Modeled latitudinal distribution of bomb
carbon-14 in the ocean, for a global mean gas
transfer velocity of 20.6 cm / hour and a
dependence on windspeed ranging from cubic to
none (n3, 2, 1 or 0).
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Robust estimates of anthropo-genic carbon uptake,
transport, and storage by the ocean (Fletcher,
Gruber, Jacobson, Doney, Dutkiewicz, Follows,
Lindsay, Menemenlis, Mouchet, and Sarmiento,
submitted)
Transport, storage (bold) and surface flux
(italics) of anthropo-genic carbon in Pg C
Estimates of anthropogenic carbon uptake (Pg C /
yr)
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Using ECCO estimates to simulate oceanic CFC
uptake
Zonal section of observed 1995 CFC-11
concentration ECCO simulation Difference
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The processes responsible for Antarctic Bottom
Water formation are poorly understood and poorly
represented in climate models.
(slide courtesy of Ilana Wainer)
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Sea-ice data products at NSIDC
What is still missing are direct observations of
sea ice thickness and snow cover.
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ASOR Arctic Sea ice - Ocean (Re)analysis (Steele
, Lindsay, Rothrock, Schweiger, Zhang, and
Menemenlis)
Arctic Ocean model configuration with 40-km
horizontal grid spacing developed by J. Zhang.
Configuration is being used to experiment with
adjoint-method estimation of coupled ocean and
sea ice system.
Adjoint-method based estimates will be compared
to ASOR optimal interpolation estimates.
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ECCO2 High-Resolution Global-Ocean and Sea-Ice
Data Synthesis
MIT Marshall, Heimbach, Hill Wunsch JPL Fu, Kwok,
Lee Menemenlis Zlotnicki GSFC Rienecker
Suarez ARC Henze, Taft HARVARD Tziperman GFDL Adcr
oft ARGONNE Hovland, Utke
Velocity (m/s) At 15 m depth
Objective synthesis of global-ocean and sea-ice
data that covers the full ocean depth and that
permits eddies. Motivation quantify role of
oceans in global carbon cycle, understand recent
evolution of polar oceans, monitor time-evolving
term balances within and between different
components of Earth system, etc., etc.
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Chaotic behavior of coupled ocean and sea-ice
models
(Kauker, Karcher, and Gerdes)
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Time-mean cost for sea ice area
Adjoint-model optimization with bulk formulae and
sea-ice
Baseline integration
Iteration 15
(Evangelinos, Heimbach, Menemenlis, and Wunsch)
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Climatology cost has been reduced by 65 in 3
iterations
High-resolution Southern Ocean state estimate
(Mazloff, Heimbach, and Wunsch)
Iter. 3 - Iter. 0
Iteration 0
Iteration 3
Temperature
Salinity
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Synthesis of the Arctic System Carbon
Cycle University of Alaska Fairbanks A.
David McGuire - lead PI Marine Biological
Laboratory Jerry Melillo Bruce
Peterson Jim McClelland Dave
Kicklighter MIT Ron Prinn Mick
Follows Purdue University Qianlai Zhuang


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Darwinian Models of Ocean Ecology and
Biogeography (M. Follows, MIT)
Single ensemble member (Iseed 5007) Modelled
annual mean surface phyto (uM P)
SeaWiFS mean Chl
SeaWiFS coccoliths (mar 03)
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Impact of high frequency variability on air-sea
gas exchange (McNeil and Menemenlis)
(Animation Henze, Hill, and Menemenlis)
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• Summary and concluding remarks
• Sea ice is relatively well observed compared to
  oceans.
• But application of sea ice data in support of
  global climate modeling is at early stage.
• For ocean carbon cycle, need improved estimates
  of water mass formation and transformation rates,
  especially in Southern Ocean and North Atlantic.
• In turn this requires increased resolution and
  improved representation of sea ice, ice shelves,
  and other high latitude processes in global
  climate models.
• Simulated coupled ocean and sea ice system
  exhibits chaotic behavior. Problem with current
  generation of models or intrinsic property of
  coupled ocean-ice system?
• Suggested estimation strategy is sequential
  estimation of uncoupled components. First
  results are promising but more work is needed.
• Back-up estimation strategies, also being
  considered but not discussed, are model Greens
  functions and multiscale approaches.