What kind of different standards and methodologies exist?

The are many different standards and related methodologies used in the certification of offsetting of greenhouse gas emissions. These can be divided into three rough groups, on the basis of their robustness:

  • UN Framework Convention on Climate Change (UNFCCC) acknowledged methodologies such as the Clean Development Mechanism (CDM). These methodologies can be found here. UN certified projects generate tradable certificates (such as CERs).
  • Voluntary carbon market (VCM) methodologies. Such standards often also attach importance to additional criteria such as biodiversity (Climate, Community and Biodiversity Alliance standards, CCB) and/or social standards (SOCIALCARBON Standard). Certificates generated by the VCM projects (which are not CDM certified) are called Verified Emission Reductions (VER), because the emissions are (externally) verified but not officially (UN) certified.
  • In-transparent carbon standards and methodologies. Many of these exist(ed) in the USA, which also led to the collapse of the Chicago Climate Exchange (CCX). In many cases the reduction of greenhouse gases was only partially or inexactly measured and very approximate assumptions were used. During the last three years, however, considerable standardization has taken place.