Similar to the AOS Greenhouse Gas Monitor (AOSGHG) and the Precision Gas System (PGS), the Precision Gas System Isotope Analyzer (PGSISO) is designed to measure the concentration of select primary greenhouse gases relevant to atmospheric study. Like those two systems, the PGSISO measures concentrations of carbon dioxide (CO2) and methane (CH4). It also additionally measures a host of additional relevant greenhouse gases - carbon monoxide (CO), nitrous oxide (N2O) and isotopes of carbon dioxide. These measurements are made at a range of heights - 2, 4, 25 and 60 meters - through the use of the tall tower at the SGP C1 facility.
As of now, please monitor the b1-level pgsiso datastream for the PGSISO DQA assignment. When submitting DQPRs for the PGSISO, please use the PGSISO instrument class. Because there is a processing delay with this instrument, it is also important to delay these DQAs by 2 weeks so that there will be a full week of data available when you go to review it. For example, don't fill out DQA week May 2nd - May 8th, 2020 until the current DQA week is May 16th - May 22nd, 2020.
For more information, please see the PGSISO Instrument web page.
In the metrics table below, the primary PGSISO measurements are outlined in red; all other measurements are diagnostic in nature. Those primary fields are:
Note that you may see some very short duration (< 5% of every hour) missing or not available QC highlighted in the PGSISO metrics tables. You can simply ignore these instances; no need to take further DQ action on them.
Daily and weekly greenhouse gas mole fractions
The PGSISO's primary greenhouse gas mole fraction measurements are plotted on both daily and weekly timescales. These include carbon dioxide (CO2), methane (CH4), water vapor (H2O), and isotopes of carbon dioxide, among others. Different colors indicate the different height levels on the tower, with cooler colors indicating lower heights and warmer colors indicating higher heights.
You may notice some diurnal and vertical variation in the greenhouse gas mole fractions. From a physical and scientific standpoint, why might we expect these variations to occur?
Daily and weekly Diagnostic data
In addition to the primary greenhouse gas mole fraction measurements, a number of diagnostic fields are also plotted to assist in monitoring overall instrument health. These include a number of diagnostic instrument temperatures, pressures and dewpoint temperatures (the sample air should be dried as part of the measurement process).
The PGSISO is located at SGP C1.
List of the behavioral quirks of this instrument that DO NOT require DQPRs nor mentions in your DQAs:
Document some here
List of the known past problems that DO need to be mentioned in your DQAs and/or DQPRs:
Document some here