The FarmAC model


The FarmAC model was developed as part of the EU AnimalChange project. It simulates the flows of carbon (C) and nitrogen (N) on arable and livestock farms, enabling the quantification of greenhouse gas emissions, soil C sequestration and N losses to the environment. It also simulates crop and livestock production. The model uses Tier 2 methodologies describe flows in livestock and manure management and Tier 3 methodologies for crops and soil. The model relies on inputs and parameters. Inputs are entered via a web-based interface and are of a type that should be available to educated, competent farmers or farm advisors. Parameters are specific to a particular agro-ecological zone (AEZ); default values are available for a range of AEZs or location-specific values can be used, if local expert knowledge is available.


The model can be used to investigate a range of farm management options on production, greenhouse gas emissions and C or N flows. It can also be used to investigate management options to compensate for negative effects of climate change or take advantage of positive effects. This is achieved by the user designing a baseline scenario and then one or more additional management scenarios.



Examples of the user interface

Try the model

User guidance

Guidance for parameterisation



Farm carbon flows






Farm nitrogen flows







User interface


Farm-scale information




Cropping sequences



Crop production potential



Ruminant livestock production



Livestock manure management



Manure and fertiliser applications



Farm commodity balance




Nitrogen flows




Carbon flows




Greenhouse gas global warming potentials and indicators





Try the model


You can try the model by going to and logging in as gs1 (password = gs1gs1). This gives you full access to the model. However, please note the following:

·         In the unlikely event that more than one person is using this guest account at the same time, there is the possibility that  the website will respond unpredictably.

·         Please create your own model farms, by starting with an empty farm or by copying a standard or existing farm.