The Arctic Boreal Zone (ABZ) Rejects More Carbon

Syllabus: GS3/Environment

Context

• According to a new study published in Nature, the increasing ferocity of wildfires means that more than 30% of the Arctic Boreal Zone (ABZ) has now stopped capturing carbon and is instead releasing it.

About

• The findings align with the National Oceanic and Atmospheric Administration (NOAA’s) 2024 Arctic Report Card.
  • It also highlighted that the Arctic tundra, a treeless region, is becoming a net carbon source, largely due to warming temperatures and escalating wildfire activity in the Northern polar region.

The Arctic Boreal Zone (ABZ)

• ABZ is a critical region in the northern hemisphere, characterized by its unique ecosystems and significant role in regulating global carbon cycles. 
• Geographical Location:
  • The ABZ spans across the Arctic Circle, including parts of Alaska, northern Europe, and Siberia.
  • It includes tundra, coniferous forests, wetlands, and permafrost regions.
• Carbon Sink: The ABZ has historically acted as a significant carbon sink, absorbing large amounts of carbon dioxide (CO₂) from the atmosphere through its forests, soil, and permafrost.
  • The tundra and wetlands in the ABZ sequester carbon in the form of organic material frozen in permafrost, which helps mitigate global warming.

Recent Wildfires:

• Multiple U.S. states (Texas, Oklahoma, California) and Japan (Ofunato) faced severe wildfires in early 2025.
• India’s forest fire hotspots dropped, but the number of fires remains high, particularly in Uttarakhand, Odisha, and Chhattisgarh.
• Rising land temperatures and prolonged heat waves contribute to more intense fires.

Carbon Emissions:

• Wildfires in January 2025 released 800,000 tonnes of carbon, nearly four times the amount released a decade ago.
• Wildfires worldwide significantly contribute to carbon emissions, including 69 million tonnes annually in India. 

Carbon Sinks and the Arctic Boreal Zone (ABZ):

• Oceans, forests, and soil are carbon sinks, but wildfires have disrupted their ability to absorb carbon.
• The ABZ, once a significant carbon sink, has started releasing carbon, especially due to thawing permafrost and increased wildfires.
• Over 30% of the ABZ now releases carbon, reversing its long-standing role as a carbon sink.

Source: TH