Amazon forests are no longer acting as a carbon sink

ENVIRONMENT/ INTERNATIONAL

Topic:

• GS-2: Effect of policies and politics of developed and developing countries
• GS-3: Conservation, environmental pollution and degradation

Amazon forests are no longer acting as a carbon sink

Context: The Amazon forests in South America, which are the largest tropical forests in the world, have started emitting carbon dioxide (CO2) instead of absorbing carbon emissions

The Amazon basin

• Covering over 6 million square kilometres, it is nearly twice the size of India.
• The Amazon rainforests cover about 80 per cent of the basin 
• Also, it is home to nearly a fifth of the world’s land species and about 30 million people including hundreds of indigenous groups and several isolated tribes.
• The basin produces about 20% of the world’s flow of freshwater into the oceans

What changes are being witnessed in recent times?

Over the last few years, the forest has been under multiple threat 

• Forest fires have doubled since 2013. One reason that they happen is when farmers burn their land to clear it for the next crop. In 2019, fires in the Amazon were visible from space.
• Deforestation in the Brazilian Amazon, which comprises about two-thirds of the area of the rainforest, started in the 1970s and 1980s when large-scale forest conversion for cattle ranching and soy cultivation began
• State policies that encourage economic development, such as railway and road expansion projects have led to “unintentional deforestation” in the Amazon and Central America.
• Amazon is therefore teetering on the edge of functional destruction

New Research Findings

• Over the years as fossil-fuel emissions across the world have increased, the Amazon forests have absorbed CO2 from the atmosphere, helping to moderate the global climate.
• However, the eastern Amazon forests are no longer carbon sinks, whereas the more intact and wetter forests in the central and western parts are neither carbon sinks nor are they emitters.
• Another reason for the eastern region not being able to absorb as much CO2 as it did previously is the conversion of forests into agricultural land, which has caused a 17% decrease in the forest cover, an area that is almost the size of continental US.
• In the southeast region, which forms about 20 per cent of the Amazon basin and has experienced about 30% of the deforestation in the last four decades, scientists have recorded 
  • 25% reduction in precipitation 
  • Temperature increase of at least 1.5 degrees Celsius during the dry months of August, September and October.
• Not only the Amazon rainforests, some forests in Southeast Asia have also turned into carbon sources in the last few years as a result of formation of plantations and fires.

Conclusion

The study shows that if the ability of tropical forests to act as carbon sinks is to be maintained, fossil fuel emissions need to be reduced and temperature increases need to be limited as well.

Connecting the dots: