The links between the carbon footprint and LCA
The carbon footprint of a product, or the inventory its life cycle GHG emissions, represents its impact on climate change. Hence, it is a subset of the life cycle assessment.
In fact, the LCA measures the potential environmental impacts of a product, process or service over its life cycle. In addition to GHG, the LCA takes into account all other material and energy inputs and environmental releases and assesses their potential impact on the environment.
The spectrum of impact categories is broad and includes: human health, ecosystem degradation, climate change and natural resource depletion. LCA is therefore a "multicriteria" analysis that assesses multiple impacts.
The carbon footprint is essentially "monocriterion" as it focuses on a single environmental impact, climate changes.
Both methods rely on functional approaches for impact assessment. In fact, a "functional unit", or quantified performance of a studied product, serves as the basis for analysis and enables comparability between products with similar functional units.