“Carbon Offsets Burning: A Major Fire in Oregon Illustrates the Challenges of Managing Forest Carbon Permanence”, 2020-09-17 (; backlinks):
In the middle of a record fire season on the US West Coast, the Lionshead Fire in Oregon burned through one of the largest forest carbon offset projects participating in California’s carbon market. Beyond the tragic effects on local communities and hazardous regional air quality, the expected carbon losses from this fire illustrate how California’s approach of using forests to mitigate climate change may need re-evaluation.
Here we analyze how future fires might affect California’s offset program and compare these likely consequences to its “buffer pool” insurance mechanism designed to protect against forest carbon loss. While quantifying the full carbon impact of the Lionshead Fire will require additional information, the available evidence highlights the risks to forest carbon permanence, many of which are accelerating in a warming climate.
…Public records from the offset program provide context for the potential scale of carbon loss from this project. ACR260 has received 2,676,483 carbon credits to date—with each credit equal to 1 metric ton of CO2—which makes it the largest credited forest offset project in Oregon and among the 15 largest forest projects in California’s carbon offset market.
Estimating forest carbon losses due to fire first requires estimating the area burned. We do this using satellites. Preliminary analysis of NASA FIRMS data, a standardized satellite product that detects and tracks fires across an array of satellites, shows that ~72% of the ACR260 project area has been burned by the Lionshead Fire through September 17, 2020.
…So is the forest buffer pool robust enough to handle the inevitable fires of the future? To explore this question, we built a simple model that asks what the experience with ACR260 means if future years have similar levels of carbon reversals…Under a scenario in which carbon loss is 50% in burned areas and events of this magnitude occur once every 4 years, fire alone could consume the entirety of the buffer pool by 2100, despite the fact that the buffer pool is intended to insure against many other non-fire risks.
…The scenarios examined here strongly suggest under-capitalization of the buffer pool and the urgent need for California to update how climate risks are treated by the forest carbon buffer pool. The already unprecedented—and on-going—fire year provides a sobering example of the importance of considering risk and permanence in a scientifically rigorous way in the context of forest carbon, carbon removal, and climate policy.