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UHDAS+ADCP Status: Monitoring from Shore

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UHDAS+ADCP Status: Monitoring at SeaΒΆ

At sea, there are three categories of monitoring:
  1. ADCP processing:

    The UHDAS web site at sea has a collection of figures that update regularly. They should be monitored to ensure that the timestamps are updating (i.e. the processing did not stall).

    At sea, these are on the Quick Links: Figures link on the UHDAS home page.

    • ADCP profile plots

      These are updated frequently at sea. Two annotated examples of the profile plots show cases with

      Note

      The profile plots should have a data timestamp not more then 10 minutes old.

    • ADCP contour plots

      These are updated every 30 minutes. In general, if the 5-minute profile plots are updating, the contour and vector plots will also update on time. These plots are most useful in providing context for science and operations.

      Plots like these are generated on land from a data snippet sent in the daily email, so a person on land or at sea can view the last 3 days of ADCP data.

      The contour and vector plots should have a data timestamp not more then 40 minutes old.

  1. health of the components:

    • heading correction

      If the ship has an accurate heading device as well as a gyro, UHDAS will keep track of the difference between the two, and plot it. An accurate heading device might be Ashtech, POSMV, Seapath, Phins, Mahrs, or other.

      There have been various generations of these plots, as we learn better how to display the heading correction in a way that will be useful with different devices. These are examples for

      Not all of these instruments have QC indicators, hence quality indicated from plots and statistics may be unrealistically optimistic. The daily text email includes an estimate of quality (summary statistics) for the accurate attitude devices specified. The exact format of the statistics generated varies slightly between UHDAS installations, as we try to better tune the information. An example of the statistics generated for the above three figures is here.

      Note

      The most likely failure for an accurate heading device is when an Ashtech loses its ability to track the satellites. If the Ashtech is yielding bad headings for more than 30-60 minutes, it may need to be reset. See this link for more detail about Ashtech errors and how to recognize them.

  1. data acquisition:

    • On the UHDAS computer console, “green is good” for the logging status.

      If a cable falls out or a feed quits coming in, the bar turns red (“red is rubbish”).

      Note

      Green only means a valid checksum was returned. There is no parsing or quality-checking done in the GUI. Example: Ashtech can have bad or missing data and a green bar