From dimitris.menemenlis at jpl.nasa.gov Tue Mar 4 18:44:06 2025 From: dimitris.menemenlis at jpl.nasa.gov (Menemenlis, Dimitris (US 329B)) Date: Tue, 4 Mar 2025 23:44:06 +0000 Subject: [ecco-support] Inquiry on Vertical Advection Discrepancy in ECCO4 References: Message-ID: Forwarding a question to the list: I hope this message finds you well. My name is Yi Chen, and I am currently a doctoral student at Beijing Normal University. I am reaching out regarding my research on the mixed-layer temperature budget based on ECCO4. Recently, I have been using ECCO v4, which you were involved in developing, to analyze IOD events during specific years. However, I have encountered a discrepancy between ECCO and GODAS regarding vertical advection. Specifically, during positive IOD events, vertical advection in the western Indian Ocean is negative in ECCO but positive in GODAS, showing opposite behaviors. Could you provide some guidance on the possible reasons behind this inconsistency? Thank you very much for your time and assistance. I greatly appreciate any insights or recommendations you can provide. Best regards, Yi Chen -------------- next part -------------- An HTML attachment was scrubbed... URL: From dimitris.menemenlis at jpl.nasa.gov Tue Mar 4 19:09:13 2025 From: dimitris.menemenlis at jpl.nasa.gov (Menemenlis, Dimitris (US 329B)) Date: Wed, 5 Mar 2025 00:09:13 +0000 Subject: [ecco-support] Inquiry on Vertical Advection Discrepancy in ECCO4 In-Reply-To: References: Message-ID: <07484034-46BB-4F71-BD7E-1E2DA11408EF@jpl.nasa.gov> Dear Yi Chen, I do not know the answer to your conundrum but I make following two remarks: 1. ECCOv4 solutions (based on adjoint method) satisfy model equations while GODAS solutions (based on a sequential method) do not. So GODAS may contain some spurious vertical advection, which is not physical. 2. Scales that are not resolved in ECCOv4 are parameterized by a vertical mixing scheme (GGL90 in case of ECCOv4). So ECCOv4 will misrepresent vertical advection for scales that it does not resolve. Hopefully other ECCO users, who are more knowledgeable with your specific problem, can provide a better answer to your question. Cheers, Dimitris On Mar 4, 2025, at 3:44?PM, Menemenlis, Dimitris (US 329B) wrote: Forwarding a question to the list: I hope this message finds you well. My name is Yi Chen, and I am currently a doctoral student at Beijing Normal University. I am reaching out regarding my research on the mixed-layer temperature budget based on ECCO4. Recently, I have been using ECCO v4, which you were involved in developing, to analyze IOD events during specific years. However, I have encountered a discrepancy between ECCO and GODAS regarding vertical advection. Specifically, during positive IOD events, vertical advection in the western Indian Ocean is negative in ECCO but positive in GODAS, showing opposite behaviors. Could you provide some guidance on the possible reasons behind this inconsistency? Thank you very much for your time and assistance. I greatly appreciate any insights or recommendations you can provide. Best regards, Yi Chen _______________________________________________ ecco-support mailing list ecco-support at mit.edu https://urldefense.us/v3/__https://mailman.mit.edu/mailman/listinfo/ecco-support__;!!PvBDto6Hs4WbVuu7!OTrMph0fsmEcqrhHJvIwW7s4y5dvDG-p7nNsU9WillcE1wnitYdaKYwMCU0knCvslcZ5-zM-D6MMMhgT7fWNjwbTkhNf11Xm0xiRny-Ll19d$ -------------- next part -------------- An HTML attachment was scrubbed... URL: