Katie Pocock Hakai Institute
1713 Hyacinthe Bay Rd Heriot Bay, BC V0P 1H0
katie.pocock@hakai.org
Dr. Wiley Evans Hakai Institute
1713 Hyacinthe Bay Rd Heriot Bay, BC V0P 1H0
(250) 914-4055 wiley.evans@hakai.org
Hakai Institute 01/05/2024 Moored Buoy 187F20221129 -127.968 -127.968 51.650 51.650 20221129 20230506 KC_B Date Time Date and Time (UTC) xCO2 SW (wet) (umol/mol) Mole fraction of CO2 in air in equilibrium with the seawater at sea surface temperature and measured humidity. CO2 SW QF Flag for xCO2 sw (wet) H2O SW (mmol/mol) Mole fraction of H2O in air from equilibrator. xCO2 Air (wet) umol/mol) Mole fraction of CO2 in air from airblock, 4 feet above the sea surface at measured humidity. CO2 Air QF Quality Flag for xCO2 Air (wet) H2O Air (mmol/mol) Mole fraction of H2O in air from airblock, 4 feet above the sea surface. Licor Atm Pressure (hPa) Atmospheric pressure at the airblock, 4 feet above the sea surface. Licor Temp (C) Temperature of the Infrared Licor 820 in degrees Celsius. MAPCO2 %O2 The percent oxygen of the surface seawater divided by the percent oxygen of the atmosphere at 4 feet above the sea surface. Disclaimer: The oxygen measurement is made in the equilibrated air. We have found that the oxygen does not come to complete equilibrium so any rapid changes in oxygen do not get properly captured using this system. Therefore, we tend to use the oxygen data only as a qualitative sense of the biology. It is not a quantitative measure. SST (C) Sea Surface Temperature. Salinity (PSU) Sea Surface Salinity. xCO2 SW (dry) (umol/mol) Mole fraction of CO2 in air in equilibrium with the seawater at sea surface temperature (dry air). xCO2 Air (dry) (umol/mol) Mole fraction of CO2 in air at the airblock, 4 feet above the sea surface (dry air). fCO2 SW (sat) (uatm) Fugacity of CO2 in air in equilibrium with the seawater at sea surface temperature (100% humidity). Since the measurements are taken at the sea surface, warming calculations are not necessary. fCO2 Air (sat) (uatm) Fugacity of CO2 in air at the airblock, 4 feet above the sea surface (100% humidity). dfCO2 Difference of the fugacity of the CO2 in seawater and the fugacity of the CO2 in air (fCO2 SW - fCO2 Air). pCO2 SW (wet) (uatm) Partial Pressure of CO2 in air in equilibrium with the seawater at sea surface temperature (100% humidity) pCO2 Air (wet) (uatm) Partial Pressure of CO2 in air at the airblock, 4 feet above the sea surface (100% humidity). dpCO2 Difference of the partial pressure of CO2 in seawater and air (pCO2 SW - pCO2 Air pH SW pH of Seawater (total scale) pH QF Quality Flag for pH 14cm - 20cm Bubble Equilibrator N/A N/A ~600 cc/min Yes yes, 1hr cycle unused unused Absolute, non-dispersive infrared (NDIR) gas analyzer Licor LI-820 1hr cycle 0.7 uatm 2 uatm 0.6 uatm 1 uatm NOAA Earth System Research& #xD;Laboratory (ESRL) At the beginning of each sample, the instrument self-calibrates using a zero and high standard. The zero standard is generated by cycling a small amount of air through a soda lime chamber. The high standard is from a cylinder of calibrated standard reference gas, 900.67 umol/mol, from ESRL. ESRL standards are traceable to WMO x93 scale with a stated reproducibility of 0.06 micromole/mole. For more information on estimates of accuracy and precision of the MAPCO2 system, see Sutton et al. 2014 (reference below). Sutton, A.J., Sabine, C.L., Maenner-Jones, S., Lawrence-Slavas, N., Meinig, C., Feely, R.A., Mathis, J.T., Musielewicz, S., Bott, R., McLain, P.D., Fought, J., Kozyr, A., 2014b. A high-frequency atmospheric and seawater pCO2 data set from 14 open ocean sites using a moored autonomous system. Earth Sys. Sci. Data, 6, doi: 10.5194/essd-6-353-2014, 353-366. 1m SeaBird SBE 16 < 0.01 ~ Annually by SeaBird Temperature data are internally recorded and collected during the equilibration period. Data are not post-calibrated. Annual drift for this deployment was minimal and does not impact the fCO2 and pCO2 calculations (within the degree of accuracy of the CO2 measurement). Contact us if you would like the CTD post-calibration information. 1m SeaBird SBE 16 < 0.05 ~ Annually by SeaBird Conductivity data are internally recorded and collected during the equilibration period. Data are not post-calibrated. Annual drift for this deployment was minimal and does not impact the fCO2 and pCO2 calculations (within the degree of accuracy of the CO2 measurement). Contact us if you would like the CTD post-calibration information. Maxtec Oxygen Sensor 2.0% Full Scale over operating temperature range. 1.0% Full Scale @ constant temperature and pressure Max-250 0.01% Factory calibrated before purchase. Recalibrated to sea level atmospheric air every 7 days Sensirion Humidity Sensor > 0.01% SHT71 Measurement range: 0-100% RH Absolute. RH accuracy: +/- 3% RH (20-80% RH) Repeatability RH: +/- 0.1% RH Factory calibrated before purchase. None o All measurements are at sea surface temperature and atmospheric pressure. o During the equilibration cycle, a closed loop of air equilibrates with seawater for 10 minutes. Once the equilibration period is complete, the pump stops and the system opens to the atmosphere allowing the pressure to equilibrate with atmospheric pressure. Measurements are recorded for 30 seconds at 2 hertz and then averaged. o During the air cycle, fresh air is pumped through the detector for 1 minute. Once the pump stops, the system opens to the atmosphere allowing the pressure to equilibrate with atmospheric pressure. Measurements are recorded for 30 seconds at 2 hertz and then averaged. o The gas streams for both the air cycle and equilibrator cycle are partially dried before entering the detector. The values listed as wet xCO2 generally have relative humidity levels ranging from 40 to 80 percent. The humidity levels increase over the course of a deployment. o Sampling occurs once every hour. The infrared detector is calibrated at the beginning of every sampling period. Averaged data and standard deviations for each measurement are transmitted back daily. o To calculate the dry measurements, the water mole fraction in the Licor detector must be known. A relative humidity sensor is located immediately downstream of the detector. o During the QC process, an adjustment to the Licor pressure is also made based on each sensor' s bias to barometric pressure as measured in the lab. This system has Licor pressure bias of +0.000 applied. The standard reference gas ran out between 04/28/2023 23:00 and 05/06/2023 20:00. Missing reference gas coefficients were computed using the correlation between Licor temperature and the coefficients in the time range of good span values. xCO2 air and sw (wet) from 11/29/2022 18:00 to 05/06/2023 20:00 were then recalculated using these computed coefficients. Post calculation correlation between Licor temperature and coefficient is: Licor coef = -0.001193 * Temp + 0.7766 r^2 = 0.97 o No data = -999 o These data are made freely available to the public and the scientific community in the belief that their wide dissemination will lead to greater understanding and new scientific insights. The availability of these data does not constitute publication of the data. We rely on the ethics and integrity of the user to assure that Hakai Institute receives fair credit for our work. Please send manuscripts using this data to Hakai for review before they are submitted for publication so we can insure that the quality and limitations of the data are accurately represented. Evans, W. 2022. High-resolution ocean and atmosphere pCO2 time-series measurements from mooring KC_BUOY.