Record-high CO ₂ emissions from boreal fires in 2021

Abstract

Extreme wildfires are becoming more common and increasingly affecting Earth’s climate. Wildfires in boreal forests have attracted much less attention than those in tropical forests, although boreal forests are one of the most extensive biomes on Earth and are experiencing the fastest warming. We used a satellite-based atmospheric inversion system to monitor fire emissions in boreal forests. Wildfires are rapidly expanding into boreal forests with emerging warmer and drier fire seasons. Boreal fires, typically accounting for 10% of global fire carbon dioxide emissions, contributed 23% (0.48 billion metric tons of carbon) in 2021, by far the highest fraction since 2000. 2021 was an abnormal year because North American and Eurasian boreal forests synchronously experienced their greatest water deficit. Increasing numbers of extreme boreal fires and stronger climate–fire feedbacks challenge climate mitigation efforts.

A Plant Species Dependent Wildfire Black Carbon Emission Inventory in Northern Eurasia

“…Wildfires are rapidly expanding into boreal forests in response to emerging warmer and drier fire seasons (Zheng et al., 2023). Better characterizing biomass burning emissions, especially over high latitude areas, is of critical importance for improving the understanding of BC‐related climate effects.…”

Contrasting trends of carbon emission from savanna and boreal forest fires during 1999–2022

“…Biomass burning (BB), a process where living or dead vegetation is combusted by open or indoor fires, occurs pervasively across the globe and represents a vital emission source for many atmospheric trace gases and aerosols (Andreae, 2019; Crutzen & Andreae, 1990). BB has been identified as an important contributor to atmospheric greenhouse gases, including CO 2 , CH 4 , and N 2 O (Barker et al, 2020; Friedlingstein et al, 2022; Shiraishi et al, 2021; Zheng et al, 2023). The burning of biomass also serves as a major source of chemically active gases such as CO, NOx, and VOCs (Pouliot et al, 2012), affecting atmospheric chemistry (Chen et al, 2017).…”

On the Role of Continuing Currents in Lightning‐Induced Fire Ignition

“…Wildfires are a key element of the Earth system, producing significant emissions of carbon dioxide, methane, nitrous oxide, carbon monoxide, carbonaceous aerosols, and other gases including non‐methane volatile organic compounds (Akagi et al., 2011; Huntrieser et al., 2016; Zheng et al., 2023). Lightning is the main natural cause of wildfire ignition worldwide (Komarek, 1964; Latham & Williams, 2001; Pyne et al., 1998) and it represents the major ignition source in low populated areas (Calef et al., 2017; Coogan et al., 2020).…”

“…Lightning is the main natural cause of wildfire ignition worldwide (Komarek, 1964; Latham & Williams, 2001; Pyne et al., 1998) and it represents the major ignition source in low populated areas (Calef et al., 2017; Coogan et al., 2020). Projections of Lightning‐Ignited Wildfires (LIW) under climate change show a possible change of pattern (Krause et al., 2014; Pérez‐Invernón et al., 2023) and a significant increase in some areas, such as in polar regions (Chen et al., 2021; Zheng et al., 2023).…”