Emissions from Amazonia increased substantially in 2019 and 2020 at the same time as large-scale, illegal deforestation was expanding across the fragile ecosystem.
Over the same period, the number of fines paid for environmental crimes dropped by almost 90%.
The figures are revealed in a study - Increased Amazon carbon emissions mainly from decline in law enforcement - by an international team of scientists and published on Wednesday 23 August in the scientific journal Nature. Professor Emanuel Gloor, from the School of Geography at the University of Leeds, was among the authors.
The Amazon represents 50% of the world’s remaining tropical rainforest, storing 90 billion tonnes of carbon in above and below-ground biomass, which can be released quickly if the ecosystem is disturbed.
A decade’s worth of environmental regulations was rolled back by the government of President Jair Bolsonaro when he took office in January 2019, having previously called the system of environmental enforcement “an industry of fines”.
The research compared carbon emissions from the Amazon between 2010 and 2018, and 2019 and 2020. Using data collected on aerial surveys of four representative sections of the rainforest, as well as satellite imaging, the team observed an increase in carbon emissions, deforestation and fires.
“Once gone, Amazonian forests will not easily regrow and even if regrown, will never be the same.”
Professor Emanuel Gloor
Deforestation rapidly increased in 2019 and 2020, up by 82% and 77% on the 2010-18 average, respectively. The result was an area of 10,129 square kilometres, just under half the size of Wales, being cleared in 2019, the highest level since 2008.
The area of land burned increased by 14% and 42% over the two years, respectively, and a greater amount of land was also used for farming and cattle grazing for the first time.
The researchers also observed that the number of infringements of laws designed to protect the rainforest decreased by 30% in 2019 and 54% in 2020 – with the number of fines paid as a result 74% and 89% below the average of the preceding eight years.
Professor Gloor said: “Altogether our results suggest that the lack of law enforcement had deleterious effects on the Amazon forests with measurable large-scale effect on atmospheric CO2.
“Once gone, Amazonian forests will not easily regrow and even if regrown, will never be the same.”
Comparable to the effect of El Niño on the Amazon
The largest increases in deforestation were seen in the 10 municipalities which already had the highest level of logging, a consequence of the Brazilian federal government removing its previously effective inspection strategy, which had focused on the most-at-risk areas.
Deforestation in the Amazon causes a regional change in temperatures and makes the dry season longer, hotter and drier, disrupting the relationship between photosynthesis and respiration.
It also makes the trees much more flammable, risking even more devastating fires in the remaining forested areas.
The regional effects also contribute to global warming, which in turn mutually reinforces heating across Amazonia.
The total amount of carbon emitted from the Amazon in 2019 and 2020 was comparable to the impact of the record El Niño weather event of 2015-16, which resulted in extremely hot temperatures and where increases in CO2 levels caused by drought in large parts of the tropics was one of the highest observed.
The study involved an international team of researchers from universities in the UK, Brazil, the United States and New Zealand, as well as the Brazilian state space agency INPE and the US’s National Oceanic and Atmospheric Administration (NOAA).
Further information
Email University of Leeds Press Officer Ben Johnson at b.johnson2@leeds.ac.uk.