Announcing a New-generation, Global, Bi-decadal State Estimate: ECCO Version 4[Feb-2014] Following the ECCO meeting in January at MIT, the JPL/MIT/AER ECCO-Production team is happy to announce the release of a new-generation, global, bi-decadal state estimate (ECCO-Production, release 1). The product covers the period 1992 to 2011. Several aspects of this new product were highlighted already during the ECCO meeting. To re-iterate, some of the features include a fully global grid (LLC90) with the inclusion of the Arctic Ocean, telescoping from 1 to 1/3 degrees in the tropics, a doubling in vertical resolution (from 23 to 50 levels), forcing with the ERA-Interim atmospheric reanalysis, and improved treatment of data sets in terms of resolved vs. unresolved scales. The state estimate is being made available on its native grid on the DODS/OPeNDAP server. The sub-directory ancillary_data have some extra information, including our standard analysis (standardAnalysis.pdf) that documents model-data misfits and physical variables of general interest. A copy of the matlab codes used to generate the standard analysis is also provided (gcmfaces_MITprof_r1.tar). As with releases of previous estimates, we think that many aspects of this release are mature (and improvements from previous versions), but further improvements of some aspects are to be expected in subsequent releases. Gael Forget has played a leading role in developing ECCO V4 and producing the released estimate.