Agriculture is a large contributor to global greenhouse gas emissions, accounting for about 10% of all U.S. emissions according to the EPA. Enteric fermentation in cattle, residue management in crops, and even the properties of soil affect emissions. While we have learned a lot as a society about how to make our agricultural systems more sustainable, there is still much room for improvement. Many farmers and corporations want to improve their environmental footprint, but it can be difficult and cumbersome to accurately measure the emissions from their farms. Life Cycle Assessments (LCAs), which analyze the environmental impact of an entire operation, can be expensive and time-consuming, so they are not ideal for repeated use in order to consistently monitor emissions.
However, there are other options that can be used to estimate agricultural emissions. There are several online greenhouse gas estimation tools available to the public, which use data input by the user to output estimates of their emissions. The existence of these tools and people’s eagerness to use them gives me hope, as I am reassured that those in the agricultural sector care about furthering their efforts to help the environment.
However, while the mere existence of these tools is a positive step, they have been around for years without reliable baseline datasets or accuracy claims. Thus, farmers and companies have likely been using a tool without knowing how accurate their results truly are, or even using multiple tools interchangeably year after year and not accounting for the differences between them. At the World Wildlife Fund (WWF), I have been working on quantifying the comparative accuracy and performance of these tools in order to help bring this important issue to light.
Different tools ask for different data and measurements and utilize different underlying methods to produce results. In my internship, I initially delved into many academic papers in order to find sufficient data to enter into the tools. I was surprised to find that the majority of these papers, which conducted detailed LCAs on dairy and crop systems, were missing crucial pieces of data, as many of these measurements can be difficult to attain. Of the few papers that I was able to enter into the tools, I found that the results given by the tools were not only different from each other, but they did not match the results in the paper either. I used a lot of trial and error in changing different metrics to try to understand how each tool was determining its results, since it was suspicious that the tools came up with different results than the papers.
Ultimately, the lack of clarity in why the results from the tools and the papers did not match up led my supervisor and I to decide to input data from hypothetical farms, in order to have all the necessary information and to create a fair comparison between tools. Currently, I am working on researching and developing hypothetical crop and dairy farm datasets to run through several tools. This will provide us with a clear comparison between different tools, without having to worry about how we interpreted the information in a paper or having to improvise certain information. Based on the initial findings of the project, I expect these trials to show that the tools produce different results for the same farm.
This project at WWF will help bring light to the imperfections of these tools, and hopefully inspire their developers to improve them, or at least help make the agricultural community aware of their lack of accuracy and comparability. I am excited that WWF recognizes the importance of this issue, as we cannot make progress in sustainability and climate change if we do not have an accurate way of estimating emissions. Even small changes in emissions make a difference, so it is important that farmers and companies have an accurate way of estimating their footprint. I am also inspired by the many well-intentioned people who have used these tools even in just a small effort to improve their agricultural practices. The tools may not be perfect, but when used with caution and a bit of skepticism, they can be an amazing asset in our fight to save the planet.