Postdoctoral Fellowship: OCE-PRF: Quantifying the effects of ocean alkalinity enhancement on costal ecosystems and atmospheric carbon dioxide

Rapidly increasing investment over the past two years into carbon dioxide removal technologies from the tech industry has accelerated the creation of ocean alkalinity enhancement (OAE) companies which are already acting in natural ecosystems. However, our understanding of olivine dissolution on atmospheric carbon dioxide (CO2) is still in its infancy.

Moreover, no studies have quantified the impact of olivine induced OAE on the benthic reef communities which populate the OAE test sites. The goal of this proposal is to characterize the effects of OAE on the functioning of the coral reef benthos and water microbial community to design a framework for measurement, reporting and verification. This proposal will evaluate the potential impacts on both the environment and atmospheric CO2, through chemostat experiments, field surveys of natural olivine beaches and biogeochemical modeling.

Controlled chemostat experiments will enable direct measurement of the olivine dissolution products including secondary mineral precipitation and their effect on reef community dynamics. The proposed research will contribute novel, fundamental knowledge to understand: 1) quantification of the dissolution rate of olivine in an ecologically relevant seawater system; 2) flux and rate of atmospheric CO2 in response to olivine OAE; 4) impact on coral reef community function.

Although multiple studies have identified plausible off-target effects such as the creation of toxic nickel as well as shifting the particle-associated microbial community composition. Before more OAE companies are created and begin impacting these vital reef ecosystems, these uncertainties and ecosystem impacts must be quantified. This proposal aims to: 1) characterize the impact of OAE on dominant reef benthic primary producers, their associated microbial communities, and dissolved organic matter cycling; 2) quantify olivine dissolution rate in reef ecosystems and the resultant drawdown of atmospheric CO2; 3) develop a biogeochemical-hydrodynamic coupled model to predict the efficacy of olivine OAE in open-ocean systems and quantify atmospheric CO2 removal on a regional scale; 4) develop new methodologies and criteria for measurement, verification and reporting for OAE.

This work has the potential to make transformative advances in OAE and guide the scaling of this new industry to systems which are best equipped to capture the most atmospheric CO2 without impacting other vital ecosystems. This project addresses challenges addressed in the National Academies of Sciences, Engineering, and Medicine: Development of an empirical framework for OAE, Assessment of the relationship between approach and environmental impact development of robust measurement, reporting, and verification strategies.

Due to the immediate need of data and accurate models for effective implementation of AOE, all data, field studies, and models will be readily available through a github repository as soon as any data becomes available, prior to publication.

This project is jointly funded by GEO/OCE Postdoctoral Fellowships Program and the Established Program to Stimulate Competitive Research (EPSCoR).

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.