{"id":558,"date":"2025-11-24T13:37:32","date_gmt":"2025-11-24T18:37:32","guid":{"rendered":"https:\/\/research.american.edu\/carbonremoval\/?p=558"},"modified":"2025-11-24T13:37:32","modified_gmt":"2025-11-24T18:37:32","slug":"if-a-tree-grows-in-the-forest-and-no-one-is-there-to-measure-it-does-it-capture-any-carbon-keelings-descent-with-ryan-davidson","status":"publish","type":"post","link":"https:\/\/research.american.edu\/carbonremoval\/2025\/11\/24\/if-a-tree-grows-in-the-forest-and-no-one-is-there-to-measure-it-does-it-capture-any-carbon-keelings-descent-with-ryan-davidson\/","title":{"rendered":"If a tree grows in the forest and no one is there to measure it, does it capture any carbon? – Keeling’s Descent with Ryan Davidson"},"content":{"rendered":"

KD #2: A few thoughts on MRV and additionality<\/strong><\/p>\n

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It\u2019s an age-old question, and it\u2019s perhaps more philosophical than anything: If a tree falls in the forest and no one is around to hear it, does it make a sound?<\/p>\n

I\u2019ve always argued that it does not. By definition, sound waves need eardrums to hit for them to constitute sounds,<\/em> as opposed to merely vibrations moving through the air. (Of course, I\u2019m assuming no squirrels, rabbits, chipmunks, or other forest-dwelling, eardrum-possessing creatures are present, either.)<\/p>\n

But a newer question, more relevant to our physical world, might be: If a tree grows<\/em> in the forest and no one is around to measure it, does it capture any carbon?<\/p>\n

The answer might not be as straightforward as you think.<\/p>\n

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Image courtesy of Tiia Monto under the Creative Commons Attribution-Share Alike 3.0 Unported license<\/a>.<\/figcaption><\/figure>\n

Let\u2019s set the stage<\/strong><\/h4>\n

Additionality and MRV (monitoring, reporting, and verification) are distinct concepts, but in many ways, they walk hand-in-hand.<\/p>\n

According to the World Resources Institute<\/a> (WRI), a \u201cCDR activity is additional<\/strong> when it can prove that it would not have otherwise happened\u201d without the influence of an organized project and the credit revenues that funded it.<\/p>\n

Also according to WRI, MRV<\/strong> is \u201ca process for tracking the outcomes of climate mitigation activities. It includes measurement, reporting, and verification to quantify and transparently share information on the outcomes of a variety of climate actions, as well as ongoing monitoring to ensure that outcomes are maintained over time.\u201d Required to verify the delta between a system\u2019s emissions (or negative emissions) with and without the desired intervention, performing robust MRV is the only way for a developer (or country, or whoever wishes to understand their emissions) to have high confidence \u2013 and any evidence \u2013 that their intervention has removed as much CO2<\/sub> from the atmosphere as they said it would.<\/p>\n

Without this robust MRV, developers don\u2019t know how much CO2<\/sub> they\u2019ve removed. Without knowing how much CO2<\/sub> they\u2019ve removed, they can\u2019t issue carbon credits. Without carbon credits, corporate buyers can\u2019t apply removals to their respective carbon budgets while developers lose the backbones of their capital stacks. Without capital, projects fall apart.<\/p>\n

MRV and additionality today are so central to the carbon removal ecosystem that sometimes it feels like we talk about the carbon removal credits<\/em> more than the carbon removal itself.<\/p>\n

Despite what The Guardian<\/em> says<\/a> (or, conversely, what it\u2026 also says?<\/a>), carbon credits aren\u2019t going anywhere. I want to be clear on that. However, I do think it\u2019s worth asking: Do we over-index on credits?<\/p>\n

How did we actually get here?<\/strong><\/h4>\n

Credits and offsets for carbon dioxide, or pollutants in general, are not new. Their history<\/a> goes back decades:<\/p>\n