Greenhouse Gas Registry – A greenhouse gas (GHG) registry is an official repository to which an entity reports emissions of one or more GHGs or changes in emission levels, typically annually. Participants can include companies reporting entity—wide or on a project–by–project basis; all or parts of state government operations; individuals; or other parties responsible for emissions or emission reductions. A GHG registry is subject to reporting and verification requirements to ensure data consistency and quality, and registries can support voluntary or mandatory reporting requirements.