Estimating the Circulation and Climate of the Ocean (ECCO)

Estimating the Circulation and Climate of the Ocean (ECCO) was initially formed under the National Ocean Partnership Program (NOPP) with funding provided by the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), the Office of Naval Research (ONR), and now the National Oceanic and Atmospheric Administration (NOAA). Its long term goal is to provide a high resolution coupled ocean/sea-ice/biochemical (and ultimately, consistent atmospheric) state estimate to a wide community. In contrast to so-called numerical weather prediction, these estimates will include the ocean's history as well as predictions. ECCO's efforts toward this goal now include several projects, each of which is bringing ECCO closer to its long term goal, while providing significant scientific contributions.

ECCO1 -- The orignal ECCO) ECCO1 refers to the initial consortium formed in 1998 by a group of scientists at the Jet Propulsion Laboratory (JPL), the Massachusetts Institute of Technology (MIT) and the Scripps Institution of Oceanography (SIO). Within ECCO1 two formal estimation strategies were pursued for solving the least-squares model vs. data misfit problem.

(1) ECCO-SIO SIO and MIT have focused on the method of Lagrange multipliers (MLM), also known as the adjoint method (or related, 4DVAR in meteorology). Initial solutions covered the period 1992 to 1997 at 2 degree horizontal resolution (version 0), and have later been extended to 2002 at 1 degree.
(2) ECCO-JPL JPL has focused mainly on an extended Kalman filter and RTS smoother approach. Solutions are produced in near real-time covering the period from 1993 to present. Its grid telescopically increases from 1 deg. at mid-latitudes to 1/3 deg. near the equator with 46 vertical levels.

ECCO-GODAE -- ECCO-GODAE is the continuation of ECCO1 beyond 2004 under NOPP sponsorship in support of GODAE and CLIVAR with funding from NSF, NASA and NOAA. Additional partners now include Atmospheric and Environmental Research (AER).

GECCO -- German ECCO (GECCO) is an extension of ECCO-SIO, now based at the University of Hamburg's Institut fuer Meereskunde (IfM). It has shifted its focus to extending the estimation to cover the full 50-year NCEP/NCAR re-analysis period, as well as to regional higher-resolution estimates in the North Atlantic.

ECCO2 -- High-Resolution Global-Ocean and Sea-Ice Data Synthesis is Phase II of the ECCO project under the NASA Modeling, Analysis, and Prediction (MAP) program.

To increase understanding and predictive capability for the ocean's role in future climate change scenarios, the NASA Modeling, Analysis, and Prediction (MAP) program is funding a project called Estimating the Circulation and Climate of the Ocean, Phase II (ECCO2): High-Resolution Global-Ocean and Sea-Ice Data Synthesis. ECCO2 aims to produce increasingly accurate syntheses of all available global-scale ocean and sea-ice data at resolutions that start to resolve ocean eddies and other narrow current systems, which transport heat, carbon, and other properties within the ocean.

ECCO2 data syntheses are obtained by least squares fit of a global full-depth-ocean and sea-ice configuration of the Massachusetts Institute of Technology general circulation model (MITgcm) to the available satellite and in-situ data. ECCO2 data syntheses are being used to quantify the role of the oceans in the global carbon cycle, to understand the recent evolution of the polar oceans, to monitor time-evolving term balances within and between different components of the Earth system, and for many other science applications.