The 2020 wildfire season alone released more carbon dioxide than what California reduced through years of emission cuts.

By Marc Campopiano and Joshua Bledsoe

California is a recognized leader in climate policy, but a wildfire crisis is threatening to unwind progress towards the state’s ambitious climate goals. In 2006, with the passage of AB 32, California set a then-unprecedented target of reducing the state’s greenhouse gas emissions (GHGs) to 1990 levels by the year 2020. Having achieved this goal, California dramatically upped the ante with the passage of SB 32, requiring a 40% reduction of GHGs, and again earlier this year with AB 1279, which requires the state to become carbon neutral by 2045 or earlier. Despite notable progress to date, a recent university study found that GHGs emitted from California’s 2020 wildfire season alone equated to more than double of all the GHG reductions the state achieved since 2003.[1]

The 2020 wildfire season was California’s most destructive on record. Wildfires are a natural part of California’s ecosystem, but decades of poor land management, drought, and increasing temperatures from climate change have caused wildfires to become more extreme and destructive in recent years. Eighteen of California’s 20 most destructive fires have occurred since 2000, and five of those were in 2020 alone.[2] During the 2020 wildfire season, fires burned approximately 4.3 million acres, killed dozens of people, and destroyed thousands of structures.[3]

According to the study, these wildfires released about 127 million metric tons of carbon dioxide (CO2). For context, from 2003 to 2019,[4] California’s ambitious climate programs reduced approximately 65 million metric tons of GHGs — less than half the GHG emissions caused by the 2020 wildfires.

Historically, the California Air Resources Board (CARB) has not considered wildfire emissions when calculating the state’s progress toward GHG targets. CARB has focused on addressing human-caused emissions, and wildfires, although potentially caused or exacerbated by human activities, are currently considered natural sources of GHGs. Further, there is scientific debate about whether wildfires result in a net increase in GHG emissions because the emissions from a wildfire may be partially or fully recaptured when new vegetation growth occurs over time and sequesters atmospheric CO2.[5] However, in 2020, wildfires were the state’s second largest source of emissions, after and almost equal to the transportation sector, and since regrowth of vegetation can take several decades, the GHGs will remain in the atmosphere and drive global climate change in the meantime.[6]

CARB has recently shifted to considering wildfire emissions when assessing California’s plans to achieve carbon neutrality by 2045.[7] CARB has included strategies to reduce wildfire emissions in its updated draft 2022 Scoping Plan, which lays out a framework for California to obtain carbon neutrality by 2045. The updated plan, released on November 16, 2022, describes strategies for proactively managing California’s natural and working lands to reduce wildfire risk and create ecosystems that sequester carbon long term. Strategies include creating diverse and resilient forests that can recover quickly from wildfires; removing excess biomass in forests, shrubland, and grassland through harvest and prescribed burns; increasing compliance with defensible space requirements; and restoring shrublands, chaparral, riparian zones, and oak woodlands across California. Because wildfires are a natural part of California’s ecosystems, the Scoping Plan’s goal is not to eliminate wildfires completely, but rather to manage lands in a way that reduces the frequency of catastrophic fires, such as those seen in 2020.

CARB will vote on the final 2022 Scoping Plan during its December 15-16 meeting. Latham & Watkins will continue to monitor further developments.

This post was prepared with the assistance of Shawna Strecker.


[1]  Michael Jerrett, Amir S. Jina, and Miriam E. Marlier, Up in Smoke: California’s Greenhouse Gas Reductions Could be Wiped Out by 2020 Wildfires (October 2022).



[4] The study used data from 2003 to 2020 to maintain consistency across three wildfire emissions inventories: Global Fire Emissions Database, the Global Fire Assimilation System, and wildfire-specific emissions estimates from the California Air Resources Board (CARB).