Quantitative Climate Science Seminar | Katja Fennel, Marine Carbon Dioxide Removal (mCDR): The good, the bad, and the ugly

Approaches for a deliberate removal of CO2 from the atmosphere by manipulating the ocean's chemistry or ecosystems (also referred to as "marine Carbon Dioxide Removal" or mCDR) are rapidly gaining attention. None of the proposed approaches are currently technologically mature enough for deployment and significant research efforts are required. In this presentation, I will share general background and some personal thoughts about this rapidly developing field before diving into currently ongoing work on ocean alkalinity enhancement (OAE) in Halifax Harbour. OAE, the deliberate increase of ocean alkalinity, is an emerging technology that is considered comparatively scalable and promises to deliver durable carbon removal. A major challenge to the successful implementation of OAE (and any other mCDR technology) is the difficulty in reliably quantifying how much CO2 is being removed from the atmosphere and for how long. Observations are inherently sparse and therefore they alone cannot provide a comprehensive quantification of the effects of OAE. Numerical models are important complementary tools that can help guide fieldwork design, provide forecasts of the ocean state, and simulate the effects of alkalinity additions on the seawater carbonate system. I will describe a coupled circulation-biogeochemical model in a nested grid configuration that reaches a very high spatial resolution in Bedford Basin and model applications in support of OAE field work.

This event is part of the NSERC CREATE-funded Quantitative Climate Science summer school. More information about this initiative can be found at https://qcs-create2024.github.io/