DAAC Home > Resources > News

News

Methane Emissions from Dairy Sources in California

Submitted by ORNL DAAC Staff on 2021-06-06
Image Media
Total annual methane emissions in 2019 from dairy farms in California.
Image Media
Caption

Total annual methane emissions in 2019 from dairy farms in California. These values represent the sum of emissions from enteric fermentation and manure management practices. Units are Gg per square kilometer per year. Source: total_CH4_CA_2019.tif

The ORNL DAAC is pleased to announce the release of a new dataset associated with The North American Carbon Program (NACP) by Marklein, A.R. et al. (2021):

Methane Emissions from Dairy Sources (Vista-CA), State of California, USA, 2019

This dataset provides estimates of methane (CH4) emissions estimated from over 1,000 dairy farms in California for the year 2019. The sources of dairy CH4 emissions are enteric fermentation and manure management reported in gigagrams per square kilometer per year (Gg km-2 yr-1). Enteric emissions at each dairy were derived from the number of cattle, dry matter intake, neutral detergent fiber in the diet, and milkfat at the dairy. Estimates of herd numbers and demographic categories came from three sources, the Regional Water Quality Control Board, San Joaquin Valley Air Pollution Control Board, and the US Department of Agriculture National Agricultural Statistics Survey.  This dataset can serve as a planning tool for mitigation, as a prior for estimating atmospheric observation-based emissions, attribution of emissions to a specific facility, and to validate CH4 emissions reductions from management changes.

The North American Carbon Program (NACP) is a multi-disciplinary research program designed to obtain scientific understanding of North America's carbon sources and sinks and of the changes in carbon stocks needed to meet societal concerns, and to provide tools for decision makers. NACP began in 2002 and continues to date. The NACP data collection contains continental carbon budgets, dynamics, processes, and management of the sources and sinks of carbon dioxide, methane, and carbon monoxide in North America and in adjacent ocean regions.

Additional data from NACP and other relevant links can be found on the ORNL DAAC's NACP Project Page.

Citation: Marklein, A.R., D. Meyer, M.L. Fischer, S. Jeong, T. Rafiq, M. Carr, and F.M. Hopkins. 2021. Methane Emissions from Dairy Sources (Vista-CA), State of California, USA, 2019. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1882

Publication Date