By: Yasmin Ajirniar
At COP21, 196 parties signed the Paris Agreement. Considering it is the first legally binding act against climate change, the international treaty is monumental. It sets a goal: keep global warming temperature change below 2 degrees Celsius. In order to do so, countries must commit to reducing greenhouse gas emissions (GHGs). Individual plans to cut back GHGs are called nationally determined contributions (NDCs). However, collaboration is encouraged to help countries meet their goals.
This is where carbon accounting, a process to quantify carbon dioxide equivalents of emissions, plays a role. The effectiveness of climate action relies on effective carbon accounting measures, especially to avoid double counting (when two countries report the same emissions reductions). Understanding these acronym helps understand how the numbers are crunched and how they stack up:
The Intergovernmental Panel on Climate (IPCC) is a United Nations body. Although it doesn't perform its own research, it complies and revises reports (e.g. Special Reports, Method Reports). Based on these reports, it objectively determines the current state of climate change. For its most recent report, check out its sixth assessment, AR6.
Internationally transferred mitigation outcomes (ITMOs) are a form of trading that is allowed under Article 6 of the Paris Agreement. Since cooperation between nation states is allowed, it is important to avoid double-counting emissions reductions.
The global warming potential (GWP) is a metric to calculate emission. It does so by using the amount of heat absorbed by greenhouse gases to quantify emissions. While gases each absorb heat differently and have different atmospheric lifetimes, the effects of different gas on global warming can be compared using the GWP. For these calculations, carbon dioxide is a reference with a value of one; other values are then calculated (and tabulated in the EPA’s Inventory of Greenhouse Gas Emissions and Sinks).
Since its adoption in 1997, modifications have afforded more accurate standards (e.g. GWP* and GTP). Although similar, the differences between carbon accounting methods demonstrates the importance of data science. Combatting the climate crisis demands collaboration between policy makers, scientists, and researchers.