Using COMET Tools to Help Farms Plan for the Future


Climate change presents real threats to U.S. agricultural production, forest resources and rural economies. Producers and land managers across the country are experiencing climate impacts on their operations through shifting weather patterns and increasingly frequent and severe storms, floods, drought and wildfire. However, producers and land managers also have an opportunity to help address climate change by mitigating greenhouse gas emissions and sequestering soil carbon.

NRCS Conservation Practice Standards have been used for decades by farmers and ranchers to enhance agricultural lands by reducing soil erosion, improving water quality, creating habitat for wildlife and a number of other benefits. In addition to these benefits, many of these practices may reduce greenhouse gas emissions and sequester carbon in woody biomass and soils. As farms look to the future, USDA’s CarbOn Management Evaluation Tools (COMET) can help estimate climate benefits of adopting certain conservation practices for cropland, pasture, rangeland, livestock operations and energy.

What Did We Do?

COMET-Farm provides a complete analysis for site-specific assessment of greenhouse gas emissions and carbon sequestration. COMET-Farm utilizes peer-reviewed greenhouse gas inventory methods sanctioned by the U.S. Department of Agriculture. Results are provided for carbon dioxide, nitrous oxide, methane and soil carbon. COMET-Planner is a web-based tool designed to provide approximate greenhouse gas mitigation potentials of implementing NRCS conservation practice standards.

The COMET tools were developed through a partnership between USDA NRCS and Colorado State University. There is more than a decade of model development experience reflected in COMET. COMET-Farm uses information on management practices on an operation together with spatially-explicit information on climate and soil conditions from USDA databases (which are provided automatically in the tool) to run a series of models that evaluate sources of greenhouse gas emissions and carbon sequestration. By integrating NRCS SSURGO database and site-specific climate data, locality-specific results are presented to COMET-Farm users. There are several modules nested within the model (i.e., Croplands, Livestock, Agroforestry, Energy), and the model relies on biogeochemical process models, IPCC methodologies, and a number of peer reviewed research results.

What Have We Learned?

Put generally, farmers, ranchers, and others can use COMET to easily estimate farm-scale GHG emissions and to explore the impacts of alternative management strategies on their net emissions. The COMET tools have a variety of additional stakeholders and users, including USDA, state governments, companies, carbon finance groups, non-governmental organization and educational institutions. There are many ways the tools can advance climate smart farming for individual farms, such as: use as part of traditional NRCS conservation planning assistance, evaluation of opportunities for farms to participate in carbon markets, as part of development of a carbon farm plan, or to quantify climate benefits for use in direct consumer marketing of farm products. Additionally, other organizations have advanced climate smart farming principles through the use of COMET, both via private industry and state government programs to incentivize conservation practices based on GHG emission reductions quantified with the tool. For examples of success stories using the COMET tools, see the links under Additional Information.

Future Plans

We look forward to continued use of the COMET tools to advance implementation of climate smart agriculture and forestry practices across the U.S.


Allison Costa, Air Quality Engineer, United States Department of Agriculture

Corresponding author email address

Additional Information

The COMET tools are available online at: and

The COMET help desk, YouTube training videos, a calendar of upcoming training events and other resources can be accessed at

Example of COMET-Planner use by Ben & Jerry’s:

Example of COMET-Planner use by the California Healthy Soils Program:


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