Organizing all the CDR standards? (Data)Based.
In this blog, we dive into the why, the how, and the what of the CRSI Quantification Resources Database.
Our goal
The Carbon Removal Standards Initiative (CRSI) provides technical assistance and capacity building for CDR policy, specifically focused on quantification standards. We believe that carbon removal is a tool for climate justice, and justice requires accountability. That means, at a basic level, we must be able to quantify any carbon removed from the atmosphere, and we must do so in a way that is transparent, scientifically rigorous, and fit-for-purpose within a given use case or regulatory context.
This sounds straightforward in theory. In practice, quantification of any CDR process is made up of numerous little steps that each require some degree of standardization. We need to calibrate sensors, baseline carbon stocks, sample fields at the appropriate spatial and temporal frequency, and a hundred other things. How do we organize all of this information into a format that is logical, searchable, and maps to real physical processes?
The Quantification Resources Database is our answer to this question.
Our approach: reservoirs and fluxes
Carbon removal refers to anthropogenic activities that result in a net flux of carbon dioxide from the atmosphere to another storage reservoir in the earth system. So, when we talk about quantifying carbon removal, we’re talking about quantifying fluxes in and out of reservoirs and adding them up to assess net removal.
As a starting point for this work, we needed a map of the geophysical fluxes relevant to carbon removal. We built this in our Carbon Reservoir and Flux Framework. We stress-tested the framework by mapping different commercial carbon removal solutions to the reservoirs and fluxes contained in our model. This taught us a lot of important lessons like, “CDR is complicated” and “We need more arrows.”
It also forced us to grapple with tough questions like, “How do we represent the carbonate chemistry system?” and “Is a wastewater facility the same type of anthropogenic, engineered carbon reservoir as a wood vault?”
If you’re curious:
For the first question, we tried variations of the framework that included bicarbonate and carbonate ions or used alkalinity as a proxy for carbonate species before we landed on our current approach using dissolved inorganic carbon.
For the second question, we decided to create two separate industrial reservoirs, wet and dry, to reflect the different chemistry involved in aqueous systems.
The Carbon Reservoir and Flux Framework in its current form reflects months of research, expert interviews, and continuous iteration. We’re excited about where we’ve landed. The flux-based approach allows us to shift our mental model from the process specifics embedded in most crediting standards (documents that provide guidance on generating a carbon removal credit to trade in the voluntary carbon market) and focus on the full climate impact of the carbon removal industry. A broader perspective is valuable when designing CDR policies that apply not just to individual project sites but across entire jurisdictions.
For example, an individual enhanced weathering technology developer might set their accounting boundary around a farm field or a set of fields, while the US Department of Agriculture might take a much broader county, state, or regional approach as appropriate for its policy goals and existing monitoring infrastructure. (Curious about this approach? Check out our blog on jurisdiction-level monitoring of enhanced weathering.)
The flux-based approach also gives us flexibility. A flux by definition is the rate at which a quantity passes through an area in a unit of time. Depending on the use case of the carbon removal process, project, or policy, we can integrate over the appropriate area (spatial boundary) and time interval (temporal boundary) to arrive at a mass of carbon removed and stored.
Equipped with the Framework, we were able to break down big documents, like 200-page crediting standards, into bite-size components and build our Quantification Resources Database.
Our Database
The Database has 3 components:
The Flux table, which lists every flux in the Framework.
The Source Document table, which contains every document, tool, and database we’ve found so far that is relevant for carbon removal quantification.
The Quantification Resources table, where every entry (or quantification resource) is uniquely identified by the source document it came from and the fluxes it describes.
As of publication, the Database contains 445 quantification resources, mapped to 156 unique fluxes, drawn from 296 source documents. You can read more about the structure and logic of the Database here.
The Database is the technical backbone of CRSI’s work. We designed it to help our team understand what quantification guidance exists in and beyond the CDR ecosystem, identify gaps, and prioritize where we can help bring consensus and consistency to CDR policy implementation. For example, we see a gap in quantification standards that take a jurisdictional approach – similar to the methodologies developed by the IPCC for national greenhouse gas inventory reporting – and an opportunity to expand the scope of CDR quantification to a broader set of use cases.
We’re sharing the Database publicly because transparency is one of our core values. We also hope that these resources will be useful for others across the CDR sector, from suppliers to buyers, registries, and market-enablers.
Looking forward
In building version 1 of the Database, we prioritized ingestion of a large volume of existing documents, breaking them down into quantifiable fluxes or combinations of fluxes. In the coming months, we will work to bring the pieces back together, building more sophisticated tools for pathway-level analysis.
We’re interested in questions like:
For a given carbon removal pathway, which fluxes are required to calculate net removal?
How many combinations of quantification resources exist for an end-to-end pathway?
How do those resources assess uncertainty individually and in combination?
What are the cost and practicality trade-offs of implementing different quantification methods?
Where are the gaps, and who is best placed to fill those gaps?
We’re not the only ones asking these deep technical questions. We’re excited to incorporate our work into ongoing efforts, in and outside of government, to increase rigor and transparency in CDR quantification.
Thank you!
Last, but certainly not least, we want to give a huge thank you to everyone who provided feedback on the Carbon Reservoir and Flux Framework and Quantification Resources Database over the last few months.
The Framework and the Database are living documents and we plan to keep iterating and learning alongside the broader CDR community.