In the course of developing agriculture and food production policy, experts aid policy makers by developing a lifecycle assessment (LCA) of an element of that policy as needed. An LCA is a tool for analyzing the environmental impacts and resources used throughout a product’s life.
An LCA is the outcome of a process that involves considering all relevant phases, such as extraction of raw materials, transport routes, manufacturing processes and disposal, and investigating the environment impact. The accuracy and relevance of this metric is often questioned – or even distorted – by those who may object to a specific production method or wish to raise questions about the impact of that method on the environment.
However, a team of nationally prominent scientists and researchers recently underscored the importance of objectively developed life cycle analyses. The experts working under the auspices of the Council for Agricultural Science and Technology (CAST) – an international consortium of scientific and professional societies, universities, companies, nonprofits, libraries, and individuals – concede that while an LCA is not a cure-all in addressing environmental issues, it is a tool that, if correctly and completely used, can logically and methodically examine environmental impacts for specific products, processes, systems, and even entire supply chains.
In its simplest form, the LCA method describes the inputs (e.g., energy, materials, and resources) to a process and all the resulting outputs including the emissions and losses to the environment. LCAs provides a modeling framework to link all processes together such that the sum of the inputs and outputs of all involved processes are included. A properly designed LCA provides a system perspective that while considering a product’s lifecycle, quantifies the relevant impacts caused by it.
A prominent example of LCAs in agriculture are those analyzing the methods used to grow a crop or produce livestock and quantifying the environmental and socioeconomic impacts associated with those activities. The purpose of LCAs is to develop a baseline understanding of the magnitude and distribution of resource demands and environmental impacts associated with production of a given commodity at a regional or national scale, along with key levers that can generate mitigation actions.
LCAs are also sometimes used for the purpose of comparing impacts between different kinds of commodities available in the marketplace in order to support prioritizing interventions or environmentally informed consumption choices.
When multiple analyses are applied to major commodity groups in the same regions, regulators can better learn how different sectors variously contribute to specific environmental concerns, whether at regional scales for issues like nutrient runoff into bodies of water or for global concerns such as greenhouse gas emissions (GHGs).
Among the most pronounced use of LCAs related to today’s agriculture sectors are those analyzing GHGs under the Renewable Fuel Standard. Lifecycle analysis – sometimes referred to as fuel cycle or well-to-wheel analysis – is used to assess the overall GHG impacts of a fuel, including each stage of its production and use
It is through these analyses that we find carbon dioxide (CO2) to be the most pervasive GHG produced since the beginning of the industrial age more than a century ago. EPA says CO2 represents 79 percent of our total climate warming emissions, a proportion that gives it the primary focus in discussions on how best to curb global warming. Much of agriculture, through efforts promoted by SfL and others, is doing its part to keep carbon in the ground during and after production.
Meanwhile, methane accounted for about 11 percent of all U.S. greenhouse gas emissions from human activities, including raising livestock and leaks from natural gas systems. It also comes from natural sources like wetlands. LCAs have shown that methane’s lifetime in the atmosphere is much shorter than carbon dioxide but is devastatingly more efficient at trapping radiation than CO2. Pound for pound, the comparative impact of methane is 25 times greater than carbon dioxide over a 100-year period.
The accuracy and relevance of LCA metrics are often questioned – or even distorted – by those who may object to a specific production method or wish to raise questions about the impact of that method on the environment. However, the findings from the prestigious CAST team underscore the importance of objectively developed lifecycle analyses – a key point that SfL respects and endorses.