Authors: Fukumori, Ichiro; Wang, Ou; Fenty, Ian; Forget, Gael; Heimbach, Patrick; Ponte, Rui M.


Version 4 Release 4 (V4r4), covering the period 1992-2017, represents ECCO's latest ocean state estimate. This product is an updated edition to that described by Forget et al. (2015, Geosci. Model Dev.). Version 4 is the first multi-decadal ECCO estimate that is truly global, including the Arctic Ocean. The Release 4 edition includes improvements in time-period (1992-2017), model (e.g., sea-ice), observations (e.g., GRACE, Aquarius), and constraints (e.g., correlated errors).

[Image at right] Global mean time-series of sea level and ocean bottom pressure (in equivalent sea level) of V4r4 in comparison to observations.

ECCO Drive:

Due to NASA's mandate to disallow the use of the ftp protocol for data access, ECCO's anonymous ftp server has been replaced by a WebDAV server called ECCO Drive. Each user must first register for an Earthdata account at https://urs.earthdata.nasa .gov/users/new in order to access the ECCO products. ECCO Drive offers a familiar interface for users to browse and download data through their browser. Additionaly, ECCO's WebDAV interface allows one to connect to ECCO as if it were a local drive. It also allows users to access data via a command line interface, enabling scripted data extracting. A detailed help page can be found at

Command line example:

To use wget to download ECCO v4r4's monthly SSH on the native grid:

wget -r --no-parent --user YOUREARTHDATAUSERNAME --ask-password

When prompted for password, you need to enter your ECCO Drive's WebDAV password, not your Earthdata account's password. To get the WebDAV password, log in with your Earthdata account from a web browser to Once successfully log in, you will be re-directed to the page of your WebDAV/Programmatic API credentials. Your ECCO Drive's WebDAV password is in the second box from top. This is the password that you would use for the wget command.

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Download Daily Fields

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Period: Jan 1992 - Dec 2017
Grid & Resolution: LLC90 (1 deg)
Domain: Global
Variable: Ocean State (temperature, salinity, velocity, sea level, bottom pressure), Fluxes (temperature, salt, volume)
Temporal Resolution: Monthly, Daily, Hourly
Data Used: Satellite Altimetry, ARGO, GRACE, Aquarius, CTD, XBT
Type of Estimation: Adjoint
Data Format(s): NetCDF, Binary
Version: Release 4
Contact Person: Ian Fenty, Ichiro Fukumori, Ou Wang
Last Updated Date: October 24, 2019


As a condition of using this product, you must cite the use of this product using the following citation.

Fukumori, I., O. Wang, I. Fenty, G. Forget, P. Heimbach, and R. M. Ponte, 2019: ECCO Version 4 Release 4, Avfailable at

Forget, G., J.-M. Campin, P. Heimbach, C. N. Hill, R. M. Ponte, and C. Wunsch, 2015: ECCO version 4: an integrated framework for non-linear inverse modeling and global ocean state estimation. Geoscientific Model Development, 8, 3071-3104, doi:10.5194/gmd-8-3071-2015

For more information, see our Use and Copyright Web page.

User Guide

A detailed description of available files and their content are summarized in a "User Guide" in the link below. Although written for the previous release (V4r3), the User Guide, in addition to other files that folllow, apply equally to the present Release 4 estimate.

Read the User Guide

Analysis Tools

ecco_v4_py: A Python package and tutorial for V4r3

gcmfaces: A general Matlab/Octave toolbox for analyzing V4r3

Guide for calculating budgets with V4r3 output

Guide for reproducing V4r4 results with MITgcm

Technical Reference


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