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<div style="direction: ltr; font-size: 12pt; color: rgb(0, 0, 0);"><span style="font-family: Aptos, Arial, Helvetica, sans-serif;">Hi
</span><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif;">JeongHyun,</span></div>
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There are essentially no differences between V4r4 and V5 interns of containing data and the methodology/production process. </div>
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References:</div>
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V4r4: </div>
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<span style="text-transform: none;">Forget, G., Campin, J.-M., Heimbach, P., Hill, C. N., Ponte, R. M., and Wunsch, C.: ECCO version 4: an integrated framework for non-linear inverse modeling and global ocean state estimation, Geosci. Model Dev., 8, 3071–3104,
https://doi.org/10.5194/gmd-8-3071-2015, 2015.</span></div>
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<span style="font-size: 12pt; text-transform: none;"><i>ECCO Consortium, Fukumori, I., Wang, O., Fenty, I., Forget, G., Heimbach, P., & Ponte, R. M. (2021, February 10). Synopsis of the ECCO Central Production Global Ocean and Sea-Ice State Estimate (Version
4 Release 4). </i></span><span style="font-size: 14.4px; text-transform: none;"><a href="https://doi.org/10.5281/zenodo.4533349" data-outlook-id="a6a65137-fb13-4df7-b20c-3eb42317505c"><i>https://doi.org/10.5281/zenodo.4533349</i></a></span></div>
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<span style="text-transform: none;">V5 Alpha:</span></div>
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Hong Zhang, Dimitris Menemenlis, Ian Fenty (2018) ECCO LLC270 Ocean-Ice State Estim.
<span style="text-transform: none;"><a href="http://hdl.handle.net/1721.1/119821" target="_blank" data-outlook-id="03a127c1-750d-4cc7-840d-e11c37d6034d">http://hdl.handle.net/1721.1/119821</a></span></div>
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Best regards,</div>
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Ou Wang</div>
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<b>From: </b>ecco-support <ecco-support-bounces@mit.edu> on behalf of JeongHyun Kim <jeongk@stanford.edu><br>
<b>Date: </b>Tuesday, June 30, 2026 at 3:29 PM<br>
<b>To: </b>ecco-support@mit.edu <ecco-support@mit.edu><br>
<b>Subject: </b>[EXTERNAL] [ecco-support] Inquiry about differences between ECCO V4r4 and V5 Alpha<br>
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Dear ECCO Support Team,</div>
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Hi, I am currently using both ECCO V4r4 and ECCO V5 Alpha in my research. While the website lists V4r4 as the latest released model, I have also downloaded V5 Alpha from ECCO Drive to utilize the higher-resolution data.</div>
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I would like to better understand the differences between these two products. I understand that they cover the same time period but differ in spatial resolution. Beyond resolution, I am particularly interested in knowing:</div>
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<div class="elementToProof" role="presentation">Are there differences in the observational data used to constrain the model between V4r4 and V5 Alpha?</div>
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<div class="elementToProof" role="presentation">Are there differences in the methodology or production process between the two versions?</div>
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Could you provide information or direct me to resources that explain these differences in detail?</div>
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Thank you for your assistance.</div>
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Best regards,</div>
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JeongHyun Kim</div>
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PhD Candidate</div>
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Department of Earth System Science</div>
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Stanford University</div>
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