Dairy operations emit trace gases such as ammonia (NH3), methane (CH4), and nitrous oxide (N2O) into the atmosphere.

Now, USDA Agricultural Research Service (ARS) scientists have quantified just how much of those gases are released from open-lot and open-freestal dairies in the western part of the country.

In this article at DAIReXNET, USDA-ARS researchers April Leytem, Robert Dungan and Dave Bjorneberg describe their findings from a study of three commercial dairies in southern Idaho.

They discuss when emissions tended to be lowest (in the late evening and early morning), as well as seasonal variation of emissions from wastewater ponds and animal-housing areas. They also describe the annual average emissions from the housing areas of the three farms involved in the study.

The researchers say their next step is to validate and improve tools that can be used to estimate emissions from dairy production systems, as well as identify management strategies to reduce on-farm emissions.