Science-based public policies are important to tackle an Amazon in transition

Paulo Artaxo, a professor at the University of São Paulo’s Physics Institute in Brazil, stresses the vital role played by research conducted in Amazonia for a deeper understanding of the global impacts of deforestation and the effects of climate change on the forest.

By Maria Fernanda Ziegler in Paris  |  Agência FAPESP – “The science produced in the Amazon is extremely important to the world. Moreover, the only way to implement the right public policies for the Amazon is on the basis of scientific evidence,” said Paulo Artaxo, a researcher at the University of São Paulo’s Physics Institute (IF-USP) in Brazil, in a presentation at FAPESP Week France, a symposium held on November 21-27 in Paris and Lyon.

Professor Artaxo is a member of the steering committee of FAPESP’s Research Program on Global Climate Change (RPGCC) and a lead author of several reports produced by the UN Intergovernmental Panel on Climate Change (IPCC).

For Artaxo, it is important to understand how to conserve the unique ecosystems in the Amazon, which is not only the largest tropical forest in the world but also the only forest that controls its own internal climate, with processes that impact the entire planet. Its unrivaled biodiversity enables the Amazon to maintain vital ecosystem services. The forest can also be a net sink of carbon dioxide (CO₂) from the atmosphere if effective conservation policies are implemented.

The forest is capable of regulating the hydrological cycle for much of South America. “The Amazon processes and exports water vapor to the atmosphere, conveying rain and humidity to various regions, including central Brazil, São Paulo State and northern Argentina, for example. Every tree processes and emits large amounts of water into the atmosphere. There are also emissions of gases, such as isoprene, and biogenic particles, which are essential to cloud formation. The entire system is integrated and optimized by nature,” he said.

Another important example of the impact of the Amazon Rainforest is its role as an enormous carbon sink. This is vital given the current state of climate change. “Amazonia accounts for 15% of the world’s primary productivity [photosynthesis], so it is a key element in the global carbon cycle. Its biomass stores between 100 billion and 130 billion metric tons of carbon. How much is that? Each year, we burn approximately 9 billion tons of fossil fuels. Therefore, it is equivalent to between ten and thirteen years of emissions from the burning of fossil fuels worldwide. It is an enormous amount and could make all the difference to global climate change,” Artaxo said.

Hydrological regulation and carbon storage, he continued, are part of a complex, nonlinear system of interaction between forest, atmosphere and soil. This system needs to be constantly studied, monitored and protected. “We know the biome and its ecosystems are under pressure from agriculture, deforestation and climate change, all of which feed into a series of important changes with regional and global impacts,” he said.

The forest is connected to the global climate in a mutually interactive manner, Artaxo explained. “Deforestation in the Amazon influences the global climate, and the global climate influences the forest very significantly. Because deforestation and climate change are impacts that are already occurring and that influence forest integrity, many studies have documented changes in the climate and carbon cycle. For this reason, it’s important to study in an integrated manner the processes and effects of these ecosystem changes,” he said.

One of the clearest impacts observed to date is the rise in average temperatures not only in the Amazon but also in other regions influenced by forest hydrology. “The annual average temperature in the Amazon is approximately 2 °C higher than at the start of last century. The global average in continental areas has risen by 1.5 °C. These increases may sound small, but they have major effects on ecosystem functioning,” he said.

The documented impacts include a longer dry season, intensification of the hydrological cycle, and a reduction in evapotranspiration by the forest, especially in the region known as the “arc of deforestation”.

Data from the scientific literature show deforestation expanding strongly. “In 1988, 5% of the Amazon had been cleared. By 2018, the proportion had jumped to 19%, and an additional 9,750 square kilometers were cleared in 2019. It is important to note that 90% of this deforestation is illegal. In a few decades, then, a major change has occurred in the Amazon Rainforest,” Artaxo said.

The impacts of environmental degradation are diverse and affect the entire country. “The most recent was widely reported by the news media. It was the river of black smoke that came from the Amazon via the states of Mato Grosso and Goiás, darkening the sky in São Paulo City [nearly 4,000 km southeast of Manaus, Amazonas State] at 3 p.m. This kind of phenomenon could become more common and can be seen in satellite images with varying intensities and frequencies,” he said.

“We’re altering the state of equilibrium that existed in the Amazon twenty to thirty years ago. Part of the biome is still in the forest stage, and part has been transformed into pasture, cropland or abandoned secondary forest.”

According to Artaxo, some studies show that if temperatures rise 4 °C or deforestation reaches 40% of the total area (up from 20% now), the remaining forest may not be able to sustain itself. If so, the impact on rainfall in South America would be enormous, as would the effect on the global climate.

Support for studies of the Amazon

FAPESP has supported many research projects designed to study the Amazon from differing and complementary perspectives. It funds several of these projects in partnership with other institutions, such as the Amazonas State Research Foundation (FAPEAM), the United States Department of Energy (DOE), the US National Science Foundation (NSF), the Belmont Forum, and the United Kingdom’s Natural Environment Research Council (NERC).

The importance of scientific research in and on the Amazon was also stressed at the symposium by Marco Antonio Zago, President of FAPESP. “FAPESP is the largest funder of research conducted in the Amazon and has one of the largest portfolios of research on climate change. For many years, the Amazon has been a strategic focus for FAPESP,” he said.

FAPESP funds more than 2,500 research projects in the Amazon and more than 2,300 research projects on climate change.

Many of these projects center on the Amazon Tall Tower Observatory (ATTO), which has been monitoring changes in ecosystem functioning since 2015 and is set to continue doing so for several decades. The ATTO is 325 m tall and located approximately 150 km northeast of Manaus. Its construction was funded by a partnership between Germany’s Max Planck Society and the Brazilian Innovation Agency (FINEP), an arm of the Ministry for Science, Technology, Innovation and Communications (MCTIC).

Brazilian state research funding agencies such as FAPESP and FAPEAM, as well as FUNPAR, the Federal University of Paraná’s foundation, are supporting research projects at ATTO. Among the ATTO projects supported by FAPESP are the Thematic Projects “GoAmazon: interactions of the urban plume of Manaus with biogenic forest emissions in Amazonia” and “Aerosol and cloud life cycles in Amazonia: biogenic emissions, biomass burning and ecosystem impacts”. Artaxo is the principal investigator for both.

Artaxo highlighted the importance of deforestation monitoring by Brazil’s National Space Research Institute (INPE) and the various satellites used to assess the carbon cycle.

“The Amazon is a laboratory where we can improve our understanding of how the climate and forest biology interact, a key factor in global climate change. We need to develop science and sustainable public policies for the use and conservation of this invaluable Brazilian heritage that is so important now and for future generations,” he said.

FAPESP Week France took place on November 21-27 thanks to a partnership between FAPESP and the Universities of Lyon and Paris. More news about the event can be found at www.fapesp.br/week2019/france.