# Presentation: 525186

## ECCO and JPL Supercomputing

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

## ECCO (1998-2004)

**ECCO (1998-2004)**
**ECCO-GODAE (2003-2009)**
**ECCO2 (2006-2011)**
**GECCO (German ECCO)**

## ECCO Near Real-Time Analysis

- I.Fukumori/JPL

- Near real-time global nowcasts every 10-days updated monthly.
- Plots @ 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 (Green’s 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

**ECCO Near Real-Time Analysis**

**Notes:**
ECCO websites.

The ECCO near real-time ocean analyses are updated regularly and are available via the ECCO Live Access Server.  The latest fields are highlighted at the JPL-ECCO home page. The web-sites are continuously being expanded to provide additional tools and results available for the general oceanographic and climate community. 

The ECCO near real-time analysis assimilates T/P (Jason-1), XBTs, TAO, & WOCE hydrography.  The model resolution is 1-deg, except in the tropics where meridional resolution decreases to 1/3-deg.  Near surface resolution is 10m down to 150m depth.  Filtered, smoothed, and unconstrained (simulation) model results are available from January 1993 to present. 

The assimilation method is based on a hierarchical approach that consists of a time-mean Green’s function method, approximate Kalman filter and smoother, and the adjoint method.   

## Applications of ECCO Estimates

**Origin, pathway & fate of “El Ni****ño**** ****Water”**

- Particle trajectory
- (Gu and Philander, 1997)

- Subtropical Cell (STC)
- (McCreary and Lu, 1994)

- Animation of Nino3 water pathway
- using a passive tracer (yrs 0~10) and its
- adjoint (yrs -10~0)

*(Fukumori et al., 2004, J. Phys. Oceanogr.)*

- I.Fukumori/JPL

**Applications of ECCO Estimates**

## Initialization of seasonal climate forecasts  using the ECCO-JPL solution

**Initialization of seasonal climate forecasts  using the ECCO-JPL solution**

**ESMF superstructure**

**DJF hindcast for March initial conditions**

**Anomaly correlation**

**Standard error**

**ECCO**

**baseline**

**persistence**

**ECCO**

**baseline**

**persistence**

**Boezio, Menemenlis, and Mechoso.**
***J. Climate*****, in press.**

## ECCO2:  High-Resolution Global-Ocean and Sea-Ice Data Synthesis

**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**
- Adcroft
**ARGONNE**
- Hovland, Utke

- 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.

- Velocity (m/s)
- At 15 m depth

## 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 )**

## Weddell Sea domain: need sea ice open boundaries!!!

- Sea ice open boundaries (work in progress):

## Adjoint sensitivity of sea ice thickness to Fram Strait ice volume transport

- 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.

## 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.