We replace our document from 3 weeks ago about estimating carbon dioxide removing (CDR) by enhanced rock weathering (ERW) utilizing measurements of alkalinity in leachate waters.
After we continued to work with the info for follow-up articles, we sadly discovered a mistake in a single calculation. For full transparency we’re documenting this error and a few enhancements to the uncertainty estimates in our replace.
The 2 substantial updates are as follows:
-
We have now improved our statistical strategy to calculate cheap estimates of the error ranges for the collected alkalinity information and added a nerd-note that explains this new strategy intimately. This transformation in calculation of the info uncertainty didn’t have an effect on the unique outcomes of our paper.
-
We discovered a bug in our code that converts the outcomes of the alkalinity measurements (in mmol over time) into the equal CO₂ captured in tCO₂/ha over time: the preliminary model confirmed values x10 too excessive. Though the relationships between experiments didn’t change, absolutely the numbers of captured carbon at the moment are significantly decrease (0.1-0.5 tCO₂/ha as a substitute of 1-3 tCO₂/ha over 10 or 11 months).
The truth that neither considered one of us, nor anybody who learn the primary model and gave suggestions on it, realized that the numbers of captured CO2 had been one order of magnitude off exhibits how unsure all of us appear to be concerning the precise numbers of observable CDR impact we are able to anticipate over brief time intervals (right here 11 months), and therefore how essential this work is.
There have been no modifications to the principle speculation, principle or sensible work in addition to these mathematical modifications. Nonetheless, since we had been updating the doc we additionally added the most recent information from December to this report and edited the textual content for readability right here and there.
Please excuse our fake pas. On our mission “to speed up negative emissions” we’re pushing for early, clear and high-frequency publishing of our information in order that they can be utilized by the complete ERW neighborhood. Which means that we take the chance of getting to appropriate ourselves as we study extra with time, however this danger appears cheap as now it occurred for the primary time in 3 years.
Please obtain the brand new model of the paper from our original blogpostfor full transparency there’s additionally a PDF with marked modifications accessible.
To obtain the subsequent replace of this story, please subscribe to our newsletter.
