Climate models predict abrupt intensification of northern wildfires due to permafrost thawing

Phys.org  September 24, 2024 Climate change will accelerate Arctic-Subarctic permafrost thaw which can intensify microbial degradation of carbon-rich soils, methane emissions, and global warming. To better understand the impact of permafrost thaw on future Arctic-Subarctic wildfires and the associated release of greenhouse gases and aerosols an international team of researchers (South Korea, Japan, Norway, USA – National Center for Atmospheric Research, University of Colorado) presented a comprehensive analysis of the effect of future permafrost thaw on land surface processes in the Arctic-Subarctic region using large ensemble forced by the SSP3-7.0 greenhouse gas emission scenario. Analyzing 50 greenhouse warming simulations, which […]

Scientists uncover hidden source of snow melt: Dark brown carbon

Phys.org  September 6, 2024 Deposition of wildfire smoke on snow contributes to its darkening and accelerated snowmelt. Recent field studies have identified dark brown carbon (d-BrC) to contribute 50–75% of shortwave absorption in wildfire smoke. d-BrC is a distinct class of water-insoluble, light-absorbing organic carbon that co-exists in abundance with black carbon (BC) in snow across the world. However, the importance of d-BrC as a snow warming agent relative to BC remains unexplored. Researchers at Washington University in St. Louis addressed this gap using aerosol-snow radiative transfer calculations on datasets from laboratory and field measurement and showed that d-BrC increased […]