The North-Atlantic is a vital component to the global carbon sink. It is estimated about one third of the global anthropogenic CO2 emissions are taken up by the ocean, with the North-Atlantic responsible for up to half of that budget. Unfortunately, exact estimates are lacking. The uncertainty in quantifying the North-Atlantic carbon sink is primarily because we lack ocean carbon measurements. Rising CO2 levels are not just a concern in the atmosphere. In the ocean, rising CO2 levels have implications for the marine carbonate system, notably ocean acidification. The effects on the ocean are already visible in Newfoundland regions near the Gulf of St. Lawrence and elsewhere in Atlantic Canada, with reduced growth rates in calcifying organisms and benthic fora.
The primary source for ocean CO2 data is from ship-based water samples. Nonetheless, sensor developments have advanced and matured over the past 20 years, and now allow year-around in-situ time series of marine carbonate levels at the stability and accuracy required for long time records. Memorial researchers have several such sensors to measure marine pH and dissolved CO2. At the recent COP26 meeting, the establishment of a North-Atlantic carbon observatory was discussed as a necessary step to monitoring and understanding the role of the North-Atlantic for future climate scenarios and managing our future emission scenarios. We propose to use the existing ocean infrastructure in Holyrood Marine Observatory to establish a local, Newfoundland shelf carbon observatory using sensors purchased as part of the recent CFI-funded DAMOS project. Sensors for this purpose have already been purchased including a Seabird Scientific Deep SeapHOX pH-CTD-DO and a Pro Oceanus Ltd. CO2-Pro CV dissolved CO2 sensor.
The development of the Holyrood Carbon Observatory would be a steppingstone for the global carbon observing community as well as a testbed for developing best practices around using in-situ autonomous CO2 sensors. There are other efforts are Memorial, led by Dr. deYoung through Ocean Frontier Institute (OFI) funded projects to establish Glider AUV-based pH sensing capabilities as well as work by Dr. Uta Passow (OSC) and Dr. Heather Reader (Chemistry) to quantify the organic and inorganic marine carbon sink in coastal shelf zones of the Newfoundland and Labrador Shelf regions. Data from the observatory would directly benefit these projects with accurate real-time data to estimate fluxes and changes in CO2 levels. There are also cross-linked activities with Fisheries and Oceans through their AZMP program, with discrete sampling of DIC, TA and other carbonate parameters on the shelf as well as Station 27, near St. John’s, with pH records going back to 2014. The Holyrood data would allow to extend the data from those sampling efforts as well as provide further insight into the changes observed in the region. There are also several HQP working on the North-Atlantic Carbon sink project in Memorial and Dalhousie, that would use these data for their research.
In a wider global context, having both a pCO2 and pH sensor at a sheltered deep coastal location with strong gradients in physical ocean properties (Temperature, Salinity and Oxygen) would provide a good place for testing of new Biogeochemical (BGC) sensors such as those used in the BGC Argo Program. There are discussions underway and Memorial could become a testbed for such sensor testing and development.