Climate Smart Agriculture practices should be differentiated based on the measurability of their impact on the carbon intensity of fuels

The Clean Air Task Force (CATF) advises the US Treasury to distinguish between different Climate Smart Agriculture (CSA) practices when calculating carbon intensity (CI) scores under section 45Z. CATF argues that no-till farming and planting cover crops should not be credited because their effects on soil organic carbon (SOC) are difficult to measure empirically, take years to occur, and are reversible. In contrast, the use of enhanced efficiency nitrogen fertilizer may remain creditable as its emissions reductions occur within a single growing season and are more easily quantified. Additionally, CATF asserts that section 45Z does not permit SOC offsets because the required methodology, such as CORSIA, does not credit SOC improvements due to permanence concerns. The document suggests that harvesting cover crops for permanent underground sequestration should be treated as a separate, potentially creditable practice if robust verification is in place.

• Treasury should not provide carbon intensity (CI) credits for no-till farming and planting cover crops under section 45Z because their impact on soil organic carbon (SOC) stocks is characterized by high spatiotemporal heterogeneity, reversibility, and a requirement for long-term monitoring that makes empirical verification difficult on timescales under 5-10 years.
• The use of enhanced efficiency nitrogen fertilizer should be treated separately from no-till and cover cropping because it reduces reactive nitrogen losses, such as nitrous oxide, within a single growing season, making its impact on CI potentially quantifiable and creditable.
• Under section 45Z, Treasury is prohibited from using SOC practice offsets in the life cycle assessment (LCA) of sustainable aviation fuel (SAF) because the mandated CORSIA methodology does not credit SOC improvements due to a lack of scientific consensus on monitoring and mitigating non-permanence.
• Harvesting cover crops to extract and permanently sequester carbon underground should be differentiated from simply planting cover crops, as it can result in gross carbon dioxide removal and permanent emissions reductions if supported by robust measurement and reporting.

APA

Firth, S. (2024). Climate Smart Agriculture practices should be differentiated based on the measurability of their impact on the carbon intensity of fuels. Clean Air Task Force. https://www.catf.us/2024/08/45z-climate-smart-agriculture-practices-should-be-differentiated-based-on-the-measurability-of-their-impact-on-the-carbon-intensity-of-fuels/

Chicago

Firth, Sammie. Climate Smart Agriculture practices should be differentiated based on the measurability of their impact on the carbon intensity of fuels. Clean Air Task Force, 2024. https://www.catf.us/2024/08/45z-climate-smart-agriculture-practices-should-be-differentiated-based-on-the-measurability-of-their-impact-on-the-carbon-intensity-of-fuels/.

Wikipedia

{{cite press release |last1=Firth |first1=Sammie |title=Climate Smart Agriculture practices should be differentiated based on the measurability of their impact on the carbon intensity of fuels |publisher=Clean Air Task Force |date=19 August 2024 |url=https://www.catf.us/2024/08/45z-climate-smart-agriculture-practices-should-be-differentiated-based-on-the-measurability-of-their-impact-on-the-carbon-intensity-of-fuels/ |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@misc{firth2024climate, author = {Firth, Sammie}, title = {{Climate Smart Agriculture practices should be differentiated based on the measurability of their impact on the carbon intensity of fuels}}, publisher = {Clean Air Task Force}, year = {2024}, month = aug, url = {https://www.catf.us/2024/08/45z-climate-smart-agriculture-practices-should-be-differentiated-based-on-the-measurability-of-their-impact-on-the-carbon-intensity-of-fuels/}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }