DESC0025190

Carbon dioxide removal using Enhanced Weathering is seen as a highly scalable means to mitigating the CO2 emissions of hard-to-abate sectors like agriculture. The largest challenge is seen in quantifying the carbon budget for enhanced rock weathering, because this decarbonization pathway leverages natural processes, like weather and soil acidification, that are inherently hard to measure with precision. This causes quantification to be both costly and uncertain, relative to the cost of the solution itself. We propose a method of measuring mineral weathering that reduces uncertainty and cost, and which enables the development of predictive models which could eventually replace the need for extensive soil sampling. This method uses immobile trace elements to estimate the carbon sequestration potential of the rocks that have been applied, the rate they dissolve, leaving the system along with CO2. Our first of a kind method of carbon quantification enables first principles models to be refined, which in the past have had very few methods for testing their performance. This can enable orders-of-magnitude lower cost in carbon quantification for enhanced weathering. While the key rationale for enhanced weathering is in managing the atmospheric CO2 budget, there are many other benefits as well, including leveraging rural communities in the supply chain, which brings liquidity into socially disadvantage regions. Additionally, enhanced weathering has been shown to improve crop yields, which increases farm incomes. Finally, value added farm products with lower carbon intensity scores improve American competitiveness by raising their value in the market, particularly with trading partners.