Life Cycle Analysis: The Science for Quantifying Green
Using natural wood products instead of fossil fuel intensive building products sharply reduces carbon emissions.
Sustainable forestry can play a major role in carbon sequestration and help to mitigate global climate change.
Through Life Cycle Analysis (LCA), scientists analyze the total environmental impact of products based on all steps, beginning with gathering raw materials to create products, and ending when all materials are discarded and returned to the earth. All raw material inputs and product outputs are measured at every stage in the product life cycle, with the perspective that all stages are interdependent. Careful analysis then considers the environmental impacts of each of these inputs and outputs to identify the net environmental impact of a particular material or product.
Wood used in long-lived products provides the greatest reduction in fossil fuel use and emissions. On average, for
every opportunity when we substitute wood for energy-intensive building products, we offset two tons of carbon
emissions for every dry metric ton of wood used. This occurs because we are displacing fossil fuel emissions that
would have been released into the air had we used more energy intensive materials, thus adding to the net benefit
of wood. Coupling this with the fact that the net carbon stored in wood products is far greater than alternative
materials it becomes clear wood has the lowest carbon impact among building materials. Builders, therefore, have
a great opportunity to mitigate carbon emissions by choosing wood products over steel, concrete and plastics.
Additional findings from CORRIM underscore the importance of sustainable forest management in mitigating carbon emissions. As trees reach maturity and growth slows, the amount of carbon removed from the atmosphere diminishes. However, the rate of removal of atmospheric carbon can be sustained by harvesting trees before their growth slows and thereby moving the carbon into wood products for permanent storage. Replacing harvested areas through reforestation with younger trees that have more vigorous carbon-storing capabilities further adds to the impact of forests' net carbon benefit.
The Consortium for Research on Renewable Industrial Materials (CORRIM) is a study group made up of fifteen research institutions. Over the last decade, CORRIM has measured the carbon input and output of forests and other building materials at every stage of their life cycle through a process called Life Cycle Analysis (LCA) and determined that forests are an integral part of the green economy. The full report containing a complete summary of CORRIM's recommendations is available here.
For more information visit the Athena Institute and explore the Environmental Protection Agency's Life-Cycle Assessment Research
Carbon Cycle: Forests and Wood are Carbon Stores
Carbon Dioxide is one of the main greenhouse gases contributing to global warming. Sustainably managed forests play
a vital role in reducing the amount of carbon dioxide released into the atmosphere. That's why it is so important
to understand the role of forests in the carbon cycle and mitigation of climate change.
Healthy, growing trees remove carbon dioxide from the atmosphere, store carbon in tree biomass and release oxygen back into the air through the photosynthesis process. The natural removal of carbon from the atmosphere is a part of the carbon cycle known as carbon sequestration. Trees accumulate and sequester carbon as they grow and when harvested, continue to store carbon in lumber, wood and paper products. Because wood products are easily recycled, carbon storage is extended beyond the life of the original product. In fact, about one-half of the weight of dry wood is stored carbon. Wood is also energy efficient for building because it requires only small amounts of energy to harvest and process. Using wood as a substitute for more energy-intensive building materials provides the greatest reduction in fossil fuel use and emissions.
Why is this important? Storing carbon in the forests and in wood products is highly effective in combating global warming. Wood has a smaller carbon footprint compared to other building materials. After it has been used as a product, wood can be combusted to produce energy that can replace fossil fuels, thereby reducing greenhouse gas emissions produced by fossil fuel consumption.
Policy: Private Forests Combat Climate Change
Private forest landowners throughout Washington State are performing an important environmental benefit to the planet, each and every day. Public policy should encourage and provide incentives for the practice of sustainable forestry, because of its role in removing carbon from the environment and storing it—both in a tree's natural and processed state.
Unnaturally overcrowded and unhealthy forests often suffer from insect and disease outbreaks, making them more susceptible to catastrophic,
destructive crown fires. For every 21,000 acres that burn, you would have to take a million cars off the road for a year to offset the emissions.
In addition, these unnatural fires can burn so hot that soil turns into clay. By actively restoring unhealthy forests, we can return the natural
forested conditions. When the natural fire cycle occurs, the emissions are going to be very minor by comparison to a forest that is so overcrowded
with trees that it burns catastrophically.
Greenhouse gas emissions from wildfire and decay are very simple to understand. The amount of biological material, biomass, wood in a particular forest dictates the emissions. In other words, the more trees you have, the greater the emissions when it burns.
Video: The Forest Factor
Policy: Avoid Catastrophic Wildfire
In 1999, the Government Accounting Office recommended that a strategy was needed to remove surplus fuel loads on federal forests. Two-thirds of the U.S. forest health problem is on federal forests.1 As Agricultural Secretary Tom Vilsack notes, " We must dramatically accelerate the scale and pace of forest stewardship here on both public and private lands. On our national forests, we must restore more acres more rapidly if we are to prevent catastrophic fires, insect outbreaks, and other threats, particularly as climate change makes those threats more potent."2
- Rummer, B. et al. 2003. A Strategic Assessment of Forest Biomass and Fuel Reduction Treatments in Western States USDA Forest Service, Research and Development and the Western Forestry Leadership Coalition.
- Vilsack, Tom. National Forest Policy address. Seward Park. Seattle, 14 Aug. 2009.