Time Series of Autonomous Carbonate System Parameter Measurements in Tampa Bay, Florida, USA

OCS Description: The Ocean Carbon System (OCS) consists of 5 sensors, 1 pump, 2 batteries, and 1 STOR-X submersible data logger. The equipment models and serial numbers (s/n) are: Pro-Oceanus CO2-Pro (s/n 049) for measurement of carbon dioxide concentration; Sea-Bird/Satlantic SeaFET pH sensor (s/n 31) for measurement of pH on the total scale; Sea-Bird SBE 16plus V2 SeaCAT C-T (P) recorder (s/n 16P40144-4781) for measurement of conductivity, temperature and depth; Sea-Bird/WET Labs ECO-PAR (s/n PARS-307) for measurement of photo-synthetically active radiation (PAR); Aanderra Oxygen Optode 4831 (s/n 116) for measurement of dissolved oxygen; Sea-Bird/Satlantic STOR-X (s/n 133) and a Sea-Bird SBE-5P submersible pump (s/n 6679). Sensor resolution is as follows: Pro-Oceanus CO2-Pro 0.01 ppm; 1mb for PRESS(IRGA); SeaFET +/-0.05 pH; Sea-Bird SBE 16plu V2s SeaCAT 0.0001 degrees C for temperature; 0.00005 siemens for conductivity and 0.002% of full scale range of 7000 meters; ECO-PAR 14-bit digital output resolution; and Aanderra Optode <1 micromol/L for concentration.
The sensors were packaged as a single unit in a custom designed platform that was mounted within a Miniaturized Trawl Resistant Bottom Mount (MTRBM). The Sea-Bird SBE-5P submersible pump pulls water through a stainless steel mesh strainer and pumps the water to the CO2-Pro for pCO2 measurement before flowing into the SeaFET for pH analysis. The sensors not requiring flow are located in close proximity to the pump intake and measure ambient water. The MTRBM has multiple openings to allow mixing with ambient water. The STOR-X is powered by two removable Satlantic Panasonic Industrial Alkaline AM-1PI battery packs, each consisting of 7 parallel sets of 10 cells in series in a factory shrink-wrapped package.
The STOR-X distributes power to the attached sensors according to a custom schedule. The OCS operates 24 hours per day, with a sampling acquisition period once every hour at the half-hour mark prefaced by a 20 minute warm up period for the CO2-Pro. The sampling acquisition period runs for 00:01:10. The CO2 sensor re-zeros every 8 hours and collects 21 CO2 and PRESS(IRGA) measurements during each sampling period. The Aanderra sensor collects 6 or 7 dissolved oxygen measurements per sample period. The ECO-PAR sensor collects approximately 30 PAR measurements per sample period. The SeaFET collects 10 pH measurements per sample period. The SBE 16Plus collects 1 conductivity, temperature and pressure measurement per sampling period.
Data Storage and Preprocessing: Data are managed and stored by the STOR-X data logger. Acquired data are saved into sensor-specific .raw files that contain the information for each Julian day. Downloading this data from the site occurs at regular intervals to ensure the sensors operational status. Downloading these .raw files from the STOR-X requires the use of STORXCom software to communicate between the STOR-X and a computer. Once the data are downloaded, SatCon version 1.5 Data Conversion program converts the .raw files into .dat files and applies any processing required. Individual sensor Julian day .dat files are then combined into one large multi-day dataset per sensor. These files are opened in Microsoft (MS) Excel 2010 and saved in the .xlsx format. The combined multiday files contain headers for each individual day file that are strung together; these must be manually removed in MS Excel leaving only the top header line. Multi-day files are then processed through a custom averaging code written in Pearl, designed by David Zawada (USGS). This code averages the multiple measurements from each sensor per sampling period to generate a single averaged value for each sensor per sampling period, reported at the start time of the sampling period and day. In addition to averaging parameter values, the code also provides the mean, standard deviation, minimum and maximum for each sampling period. Averaged data for each sensor parameter are then manually merged into a single .xlsx file for further processing. Data files are deleted from the STOR-X after confirmation of successful download and storage of parameter data.
Advanced Data Processing: Preliminary QA/QC of sensor data are performed after averaged data are compiled into .xlsx files and after advanced data processing is performed. The SeaFET pH data are corrected for salinity and temperature, using Sea-Bird SBE 16plus SeaCAT C-T (P) recorder data through a MS Excel macro provided by Satlantic. The Satlantic macro is also used to calibrate the SeaFET pH data to discrete pH measurements determined in- situ and concurrently with OCS sample acquisition using, spectrophotometric pH methods. Aanderra dissolved oxygen (DO) data are corrected for temperature, salinity, and pressure using the Sea-Bird SBE 16plus SeaCAT C-T (P) recorder data and a MS Excel macro provided by Aanderra. Once corrections have been completed, parameter data are plotted to examine sensor performance and identify non-trending outliers. Cross validation of sensor parameters is performed to further analyze outliers and identify questionable or bad data points. Preliminary QA/QC does not include validation of sensor data against discretely measured parameters and are, thus, considered preliminary, non-validated data.

Added keywords section with USGS persistent identifier as theme keyword.