Climate change occurs when changes in the climate system result in new weather patterns and is one of the major challenges facing the global population and the natural environment.
Greenhouse gas (GHG) emissions released into the atmosphere in ever rapidly growing volumes are recognised to be responsible for this change. A carbon footprint measures the total greenhouse gas emissions caused directly and indirectly by a person, organisation, event or product.
Carbon footprint quantification analysis and reduction are key to preventing this change by, for example, enhancing energy efficiency, mitigating carbon emissions by means of green energy and then compensating for remaining GHG emissions by investing in carbon offsets, with a final goal of being carbon neutral.
The carbon footprint is the fastest growing part of humanity’s overall ecological footprint – it accounts for 54% of the overall ecological footprint.
What is a Carbon Footprint?
A carbon footprint (CF) – also named carbon profile – is the overall amount of carbon dioxide (CO2) and other greenhouse gas (GHG) emissions (e.g. methane, laughing gas, etc.) associated with a product. A carbon footprint comprises the entire supply chain, sometimes including the use and recycling or the disposal of the product.
Causes of greenhoue gas emissions are, for example, electricity production in power plants, heating with fossil fuels, transport operations and other industrial and agricultural processes.
A carbon footprint is quantified using indicators such as the Global Warming Potential (GWP). As defined by the Intergovernmental Panel on Climate Change (IPCC), a GWP is an indicator that reflects the relative effect of a greenhouse gas in terms of climate change considering a fixed time period, such as 100 years (GWP100). The GWPs for different emissions can then be added together to deliver one single indicator that expresses the overall contribution to climate change of these emissions.
Understanding Carbon Footprint – What is Global Warming Potential (GWP)?
Carbon Footprint and LCA
A carbon footprint is a sub-set of the data covered by a more complete Life Cycle Assessment (LCA).
LCA is an internationally standardized method (ISO 14040, ISO 14044) for the evaluation of the environmental burdens and resources consumed along the life cycle of products; from the extraction of raw materials, the manufacturing of goods, their use by consumers or the provision of a service, recycling, energy recovery and ultimate disposal.
One of the key impact categories considered in an LCA is climate change, typically using the IPCC characterization factors for CO2 equivalents. Hence, a carbon footprint is a life cycle assessment with the analysis limited to emissions that have an effect on climate change.
Suitable background data sources for the footprint are therefore those available in existing LCA databases. These databases contain the life cycle profiles of the goods and services that you purchase, as well as of many of the underlying materials, energy sources, transport and other services.