| Contributors | Affiliation | Role |
|---|---|---|
| Johnson, Zackary I. | Duke University | Principal Investigator, Contact |
| Hunt, Dana | Duke University | Co-Principal Investigator |
| Rauch, Shannon | Woods Hole Oceanographic Institution (WHOI BCO-DMO) | BCO-DMO Data Manager |
Dissolved inorganic carbon (DIC; uM Carbon) from the Pivers Island Coastal Observatory (PICO) from 2010 to 2012.
Note: DIC was not measured at all time points, thus, some dates have no data ('nd') in the 'DIC' column.
Water was sampled using a 5 L niskin bottle centered at 1 m with a bottle length of 0.7 m. DIC was measured on mercuric chloride poisoned samples by acidification and subsequent quantification of released CO2 using a CO2 detector (Li-Cor 7000). DIC samples were collected following recommended procedures (Dickson et al., 2007) and measurements were calibrated against Certified Reference Materials provided by Dr. A. G. Dickson at Scripps Institution of Oceanography (SIO), University of California, San Diego (UCSD).
References:
Dickson, A.G., Sabine, C.L., and Christian, J.R. (eds) (2007) Guide to best practices for ocean CO2 measurements: PICES Special Publication 3.
Quality Scores (qflag) as follows:
1 = excellent (no known issues),
2 = suspect,
3 = poor (known reason to suspect data).
BCO-DMO Processing Notes:
- Created 'replicate' column and re-arranged data so that replicates are in rows, not columns.
- Modified parameter names to conform with BCO-DMO naming conventions.
- Replaced blanks with 'nd' to indicate 'no data'.
- Separated date into month, day, and year columns.
| File |
|---|
DIC.csv (Comma Separated Values (.csv), 84.11 KB) MD5:f1bcdb33a4ee8f95a43aefcd9f2c6df4 Primary data file for dataset ID 4031 |
| Parameter | Description | Units |
| deployment | Deployment name/id number. | text |
| lat | Latitude of sampling location. Positive = North. | decimal degrees |
| lon | Longitude of sampling location. Positive = East. | decimal degrees |
| year | Year (local time) of the sampling event. | YYYY |
| month_local | Month (local time) when the sampling event occurred. | mm (01 to 12) |
| PID_num | Unique, sequential "occupation" number for sampling. (The unique time/day when sampling occurred.) | dimensionless |
| day_local | Day of month (local time) when the sampling event occurred. | dd (01 to 31) |
| time_local | Time (local) when the sampling event occurred; 24-hour clock. | HHMM.mm |
| time_qflag | Quality score for time_local: | dimensionless |
| depth | Depth of water sampling. | meters |
| replicate | Replicate identifier. (All of the "A" DIC samples are from the same bottle, however "A" replicates for DIC are unrelated | text |
| DIC | Dissolved inorganic carbon. | micromolar Carbon (uM C) |
| DIC_qflag | Quality score for DIC: | dimensionless |
| yrday | Consecutive day of year for a specified year, as a decimal. The fraction of the value represents the time within the day (e.g. a value of 1.5 means January 1 at 1200 hours). | dimensionless |
| ISO_DateTime_Local | Date-time (local) formatted to ISO 8601 standard. | YYYY-MM-DDTHH:MM:SS.ss |
| Dataset-specific Instrument Name | LI-COR LI-7000 Gas Analyzer |
| Generic Instrument Name | LI-COR LI-7000 Gas Analyzer |
| Dataset-specific Description | DIC was measured on mercuric chloride poisoned samples by acidification and subsequent quantification of released CO2 using a Li-Cor 7000 CO2 detector. |
| Generic Instrument Description | The LI-7000 CO2/H2O Gas Analyzer is a high performance, dual cell, differential gas analyzer. It was designed to expand on the capabilities of the LI-6262 CO2/ H2O Gas Analyzer. A dichroic beam splitter at the end of the optical path provides radiation to two separate detectors, one filtered to detect radiation absorption of CO2 and the other to detect absorption by H2O. The two separate detectors measure infrared absorption by CO2 and H2O in the same gas stream. The LI-7000 CO2/ H2O Gas Analyzer is a differential analyzer, in which a known concentration (which can be zero) gas is put in the reference cell, and an unknown gas is put in the sample cell. |
| Dataset-specific Instrument Name | Niskin bottle |
| Generic Instrument Name | Niskin bottle |
| Dataset-specific Description | Water was sampled using a 5 Liter niskin bottle. |
| Generic Instrument Description | A Niskin bottle (a next generation water sampler based on the Nansen bottle) is a cylindrical, non-metallic water collection device with stoppers at both ends. The bottles can be attached individually on a hydrowire or deployed in 12, 24, or 36 bottle Rosette systems mounted on a frame and combined with a CTD. Niskin bottles are used to collect discrete water samples for a range of measurements including pigments, nutrients, plankton, etc. |
| Website | |
| Platform | Duke University Marine Lab |
| Start Date | 2010-06-28 |
| End Date | 2012-06-26 |
| Description | The PICO time series is sampled weekly (or more frequently) to capture physical, chemical and biological variability in the coastal ocean. This time series enables the investigator to collaborate with a number of researchers and will serve as a long-term research focus.
Project information: http://oceanography.ml.duke.edu/johnson/research/pico/ |
From the project website:
Carbon dioxide is rising at ~3% per year in the atmosphere and oceans leading to increases in dissolved inorganic carbon and a reduction in pH. This trend is expected to continue for the foreseeable future and ocean pH is predicted to decrease substantially making the ocean more acidic, potentially affecting the marine ecosystem. However, coastal estuaries are highly dynamic systems that often experience dramatic changes in environmental variables over short periods of times. In this study, the investigators are measuring key variables of the marine carbon system along with other potential forcing variables and characteristics of the ecosystem that may be affected by these pH changes. The goal of this project is to determine the time-scales and magnitude of natural variability that will be superimposed on any long term trends in ocean chemistry.
Other PICO-related projects in BCO-DMO:
Ocean Acidification: microbes as sentinels of adaptive responses to multiple stressors: contrasting estuarine and open ocean environments
| Funding Source | Award |
|---|---|
| NSF Division of Ocean Sciences (NSF OCE) | |
| NSF Ocean Sciences Research Initiation Grants (NSF OCE-RIG) |