California Air Resources Board

Principal Investigator/Author: William Horwath

Contractor: University of California, Davis

Contract number: 23RD017

Project Status: Active

Relevant CARB programs: AB 32 Climate Change Scoping Plan, Nitrous Oxide Emissions from California Lands

Topic areas: Climate Change, Greenhouse Gas Emission Inventory Program, Greenhouse Gas Inventory

Research Summary:

This project will evaluate the current state of the science on nitrogenous emissions from soils in California, emphasizing agricultural regions where synthetic nitrogen fertilizers and organic nitrogen materials are applied. Researchers will work with the Subject Matter Expert Review Panel on nitrogenous emissions from soils to comprehensively review available scientific literature, pertinent databases, and emission estimation methodologies that improve the understanding of the accuracies and uncertainties associated with nitrogenous emission predictions for soils. This project will also identify potential research gaps in this area. The research team will be answering specific questions posed in the project tasks and providing quantitative evidence and comprehensive justifications that support the responses and conclusions set out by the Panel. They will conduct additional modeling and sensitivity analyses to corroborate the findings as appropriate. 

Tasks include:

• Coordinate with Panel members and hold meetings twice a month to answer a series of questions about California-specific nitrogenous emissions from soil;
• Conducting a comprehensive review of nitrogenous emissions from soils using scientific literature, relevant databases, and emission estimation methodologies; and
• Formulate future research, air monitoring recommendations, and responses to questions into a Final Report.

Keywords: nitrous oxide (NOx), soil, nitrogenous emissions, soil emissions, nitrogen