During data review to troubleshoot negative fDOM values, NEON discovered that some fDOM values published in the Water quality (DP1.20288.001) data product are artificially low. According to the manufacturer, this resulted from hardware interference in probes manufactured before June 2017 that causes a non-linear response, especially at low ranges. The manufacturer corrected the defect and data from newer probes are not impacted. We are currently working to determine the scope of the problem by ascertaining sites and date ranges where older model probes were deployed. We are also determining whether equations provided by the manufacturer can be used to post-correct affected data after re-processing. Moving forward, we plan to replace older model probes so that the issue does not continue.
An update will be provided by the end of June, 2022 with more details on impact scope and resolution timeline. For more detailed information on the problem please use the data portal contact form. Select DP1.20288.001 in the Data Product dropdown list and include the term “INC0052659” in the body of your request.