From: Esther Kennedy Date: Tue, Aug 29, 2023 at 5:07 PM Subject: Update to NCEI 0277984 To: Alex Kozyr - NOAA Affiliate Hello Alex, I have two updates and requests related to our MOCHA dataset (NCEI Accession 0277984). First, we recently discovered a years-old quality-control error with a few of the total alkalinity measurements collected by the MOCHA author team, associated with autotitrator runs that had poor standard precision and accuracy. We have dropped all affected total alkalinity observations. In total, this issue impacted a subset of three small datasets and has led us to entirely remove a fourth (dataset 38) pending further review. These updates amount to very small changes to the full MOCHA dataset, our total alkalinity review only encompassed 1500 observations and the affected total alkalinities comprised about 25% of the total reviewed, but we would like to update our NCEI materials with these changes as soon as possible. Unfortunately, this discovery has also required minor updates to our abstract (to update the number of datasets included), dataset subsets, and dataset metadata file. Aside from pulling impacted total alkalinity measurements, we have made no further updates to the MOCHA dataset. At the request of our manuscript reviewers, we would also like to add a summary dataset that's been aggregated and averaged by location, depth, project, and day. This aggregated dataset is only 1.5 million rows, rather than 13.7 million rows, and could provide a useful alternative for users to the data subsets we have already made available. I have updated our abstract to include this aggregated dataset and have included it here with our updated submission materials ("aggregated_daily_dataset.csv"). When possible, could you update our NCEI materials with these updated materials? Is there any further information or material I should provide? Thank you very much for your help, - Esther Kennedy Attachments: NCEI_submission_update_v2.zip