The greenhouse gas (GHG) Protocol Corporate Standard classifies a company’s GHG emissions into three categories or “scopes.” Scope 1 emissions are direct emissions from owned or controlled sources. Scope 2 emissions are indirect emissions from the generation of purchased energy (including but not limited to electricity, steam, heating and cooling) consumed by the reporting company. Scope 3 emissions are all indirect emissions (not included in scope 2) that occur in the value chain of the reporting company, including both upstream and downstream emissions.
Product life cycle emissions
As defined by the Greenhouse Gas Protocol, product life cycle emissions are “all the emissions associated with the production and use of a specific product, from cradle to grave, including emissions from raw materials, manufacturing, transport, storage, sale, usage, and disposal.” The product life cycle emissions standard accounts for emissions at the level of a specific product.
Net zero and limiting global warming to 1.5°C
According to the Intergovernmental Panel on Climate Change (IPCC), limiting global temperature increase at any level requires global CO2 emissions to reach net zero at some corresponding point in the future and reducing non-CO2 radiative forcing as much as possible. In model pathways that limit global warming to 1.5°C, with no or limited overshoot, global net anthropogenic CO2 emissions decline by about 45% from 2010 levels by 2030, reaching net zero around 2050.
IPCC Model Pathways that limit warming to 1.5°C with no or limited overshoot use carbon dioxide removal (CDR) to some extent to offset emissions from sources that are difficult to abate and, in most cases, also to achieve net negative emissions to return global warming to 1.5°C following a peak. In case of delays in reducing CO2 emissions toward zero, the longer the delay, the larger will be the likelihood of exceeding 1.5°C, and the greater will be the reliance on net negative emissions after mid-century to return warming to 1.5°C.
Sources: Greenhouse Gas Protocol, IPCC Special Report “Global Warming of 1.5°C,” and IPCC Sixth Assessment Report