ECCO and JPL Supercomputing

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• ECCO and JPL Supercomputing
• Dimitris Menemenlis
• October 31, 2007
• ECCO and ECCO-children
• JPL-ECCO Ocean Data Assimilation
• ECCO2
• JPL supercomputer usage by ECCO

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ECCO (1998-2004) ECCO-GODAE (2003-2009) ECCO2
(2006-2011) GECCO (German ECCO)
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ECCO Near Real-Time Analysis

• Near real-time global nowcasts every 10-days
  updated monthly.
• Plots _at_ http//ecco.jpl.nasa.gov/external
• SSH (T/P, Jason-1), Temperature profiles (XBT,
  TAO, ARGO, etc), time-mean sea level (drifters,
  GRACE) are assimilated.
• A hierarchical assimilation system is used
  (Greens function, Kalman filter Smoother,
  Adjoint method)

• Web-based circulation pathway tool using passive
  tracers their adjoint
• Results are available via ECCO LAS server from
  1993 to present http//www.ecco-group.org/las

I.Fukumori/JPL
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Applications of ECCO Estimates
Origin, pathway fate of El Niño Water
Particle trajectory (Gu and Philander, 1997)
Animation of Nino3 water pathway using a passive
tracer (yrs 010) and its adjoint (yrs -100)
Subtropical Cell (STC) (McCreary and Lu, 1994)
(Fukumori et al., 2004, J. Phys. Oceanogr.)
I.Fukumori/JPL
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DJF hindcast for March initial conditions
Initialization of seasonal climate forecasts
using the ECCO-JPL solution
ECCO
baseline
persistence
Anomaly correlation
ECCO
baseline
ESMF superstructure
persistence
Boezio, Menemenlis, and Mechoso. J. Climate, in
press.
Standard error
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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 improved estimates
and models of ocean carbon cycle, understand
recent evolution of polar oceans, monitor
time-evolving term balances within and between
different components of Earth system, etc.
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22-23 January 2007 ECCO2 meeting Early User
Applications
Subtropical mode water (Maze, MIT) Eddy
propagation velocity (Fu, JPL) GRACE data
constraints (Zlotnicki, JPL) Errors estimates
(Forget, MIT) Eddy parameterizations (Ferreira,
MIT) Arctic freshwater budget (Condron,
WHOI) Arctic sea ice budget (Kwok, JPL) Sea ice
data/model comparison (Nguyen, JPL) Carbon cycle
modeling (Manizza, MIT) Eddy variability in
Indian Ocean (Lee, JPL) Darwin project (Hill,
MIT) Southern Ocean (Schodlok, JPL) MITgcm
assimilation efforts (Cornuelle, SIO) Adjoint
assimilation efforts (Edwards, UCSC )
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Weddell Sea domain need sea ice open
boundaries!!!
Sea ice open boundaries (work in progress)
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Adjoint sensitivity of sea ice thickness to Fram
Strait ice volume transport
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• ECCO2 web site
• and data server
• 150 TB of local online disk storage available
  within JPL via nfs and outside JPL via ssh using
  JPL supercomputing account.
• 40 TB is made available via ftp and http outside
  JPL by JPL PO.DAAC.

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• JPL supercomputer usage by ECCO
• Long history of enabling cutting edge research
• Cray and HP-Examplar were instrumental in
  enabling original ECCO proposal.
• Origins were workhorse for JPL-ECCO
  quasi-operational analysis.
• Altix permitted development of cubed-sphere
  configuration, later ported to NAS, and helping
  to get ECCO2 underway.
• JPL supercomputing resources are currently used
  by ECCO for
• Debugging and preparing code, e.g., sea-ice open
  boundaries, adjoint sensitivities. Need quick
  turn-around large but short jobs.
• Science analysis of ECCO-GODAE and ECCO2
  results. Need large online storage, directly
  available to JPL workstations.
• Distribution of ECCO-GODAE and ECCO2 results.
  Need large online storage, accessible to outside
  users with few restrictions and some moderate
  processing.
• Smaller-scale computational studies, which it
  does not make sense to port to NAS or Goddard
  facilities, e.g., offline tracer, regional,
  coarse-resolution coupled, etc.