GHG Accounting Uncertainty

From Open Risk Manual

Definition

GHG Accounting Uncertainty is the Uncertainty surrounding GHG Accounting[1], [2]

Project based GHG accounting involves many forms of uncertainty, including

  • uncertainty about the identification of secondary effects
  • the identification of baseline candidates
  • baseline emission estimates, and
  • the measurement of GHG project emissions.


The combination of quantitative uncertainty values is strongly linked to the equations used to estimate emissions and removals. Simple methods are based on equations that multiply Activity Data (AD) by an emission factor (EF). More generally, both AD and EF can be the result of several different parameters. Uncertainties associated with GHG reductions can be categorized into “scientific uncertainty” and “estimation uncertainty.”

Scientific Uncertainty

Scientific uncertainty arises when the science of the actual emissions and/or removal processes is not completely understood.

Estimation Uncertainty

Estimation Uncertainty arises any time GHG emissions are monitored and quantified, and can be further divided into “model uncertainty” and “parameter uncertainty.”

Mitigation

Where uncertainty is significant, lower and upper bounds or confidence intervals for all measurements should be identified.

Issues and Challenges

  • The GHG Project Protocol contains no explicit requirements for addressing uncertainty
  • The degree of conservatism that must be applied (if any) varies between different accounting frameworks and practices

See Also

References

  1. The GHG Protocol for Project Accounting, 2005
  2. 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories