LCA tracks emissions, which are substances released into the air, water or soil. Of key importance are greenhouse gas (GHC) emissions, which contribute to the disruption of the global climate.
The many names of "carbon"
The following is a list of terms that are often used somewhat interchangeably to refer to the emissions associated with climate change or global warming :
- Carbon footprint
- Carbon dioxide (CO2)
- Carbon dioxide equivalent (CO2e or CO2eq)
- Greenhouse gas (GHG) emissions
- Fossil fuel emissions
- Global warming potential (GWP)
- Climate change (CC) potential
These terms do not share the exact same meaning. Even though the term "carbon" is commonly associated with climate change, it is technically not elemental carbon that contributes to climate change, but carbon dioxide gas along with many other substances such as nitrous oxide and methane. Nevertheless, "carbon" is often used as an abbreviation to refer to global warming potential.
Embodied and operating carbon
LCA can assess many environmental impacts, but GWP is often the focus of LCA studies. Embodied carbon commonly refers to the GWP attributed to materials and energy used in the construction and maintenance of buildings. Operating carbon refers to the GWP attributed to operation and use of the building.
Carbon Leadership Forum - Life Cycle Assessment of Buildings: A Practice Guide