Study collects data on the emissions from burning in Amazonia

Study collects data on the emissions from burning in Amazonia

By Karina Toledo

Agência FAPESP – A group of Brazilian and British researchers began flying over Amazonia on September 12 to understand how the emissions from fires in the region are changing the local and global climate.

With the help of cutting-edge technology, scientists are collecting data on the chemical composition and physical properties of the smoke emitted. They are also verifying how gases and the solid particles released into the air modify the composition of clouds, change the atmospheric chemistry and interact with solar radiation.

“We have conducted 35 flight hours to date. Our target is to reach 60 to 70 hours through October 5, when the data collection phase ends,” comments Paulo Artaxo, professor at Universidade de São Paulo (USP) and one of the coordinators of the South American Biomass Burning Analysis (SAMBBA).

SAMBBA, the result of partnership between USP, the National Institute for Space Research (INPE), University of Manchester and UK-Met-Office, the British meteorological service, was highlighted in the weekly news segment of Nature magazine’s website.

The initiative is funded in part by the U.K.’s Natural Environment Research Council (Nerc), which provided support for the aircraft. Several British universities granted the equipment used to collect data.

In Brazil, the experiments are being funded by FAPESP through its Regular Research Grants programs, one coordinated by Artaxo and another by INPE’s Karla Longo.

“The project originated from the ongoing cooperation between INPE and UK-Met-Office over the past few years for development of climate forecast models,” explains Longo.

Both the British and Brazilian researchers felt the need to better the predictability of models for the Amazon region. “The impact of the burning on climate forecasting is still not very well known,” she explains.

Ben Johnson of UK-Met-Office stresses that Amazonia is among the world’s four largest regions for biomass burning. “We conducted similar experiments in countries such as Canada and South Africa. The forecasts of our meteorological service cover the entire globe, and we hope, with these South American data, to improve the quality of our forecasts,” he comments in an interview with Agência FAPESP.

Planning

A large team of scientists has participated in planning the data collection missions that cover the majority of the Amazon Basin, explains Artaxo.

To do so, scientists have analyzed satellite data, projections conducted by existing climate models and information from the Aerosol Robotic Network (Aeronet) – a network in partnership with USP and NASA that conducts frequent measurements of the aerosol column, the solid smoke particles over the Amazon.

“We combined all this information to decide where to fly and what type of flight to do. We can make measurements at an altitude of 150 meters to analyze the properties of recently emitted smoke or at an altitude of 12 kilometers to see the physical-chemical changes in older smoke that is transported by convection,” explains Artaxo.

The research plane, a large four-engine jet, is equipped with mass spectrometers, ozone monitors, greenhouse gas monitors and light absorption and light scattering photometers. There is also Lidar equipment, a laser device that measures the vertical distribution of aerosol particles each second.

“The equipment can make extremely precise measurements in high temporal resolution. In the case of greenhouse gases (CO₂, CH₄, N₂O), for example, the margin of uncertainty is 0.1%,” comments Artaxo.

According to the researcher, they are analyzing both the emissions resulting from deforestation and from burning in agriculture and for pasture maintenance.

“Although these two types of burning are concentrated in different regions of the Amazon –deforestation in the North, near northern Mato Grosso, and agriculture close to the border with the Cerrado – the emissions are relatively close and mix with the atmosphere,” he adds.

One of the study’s objectives is to evaluate the difference between these two types of emissions and the contribution of each to the greenhouse effect and climate change in the region. “We measured the quantity of sulfate, nitrate and organic material in smoke in real time. We also analyzed the physical properties of solid particles, such as sizes as small as 10 nanometers, and absorption coefficients and radiation scatter. All this is related to the impact of emissions on climate and on the Earth’s radiation budget,” explains Artaxo.

The group also measures the concentration of carbon monoxide, ozone, nitrogen oxides and volatile organic compounds. “There is an enormous range of volatile organic compounds, and many of them were never measured in burning in Brazil,” he affirms.

After completing data collection, scientists will begin the process of analyzing the large quantity of information and improving the climate models, which should take approximately 4 years by their estimates.

“Climate models are numerical representations of chemical and physical processes that occur in the atmosphere. It is necessary, however, to become familiar with the phenomena to build a set of equations that represent them in a precise manner,” highlights Longo.

Other members of the SAMMBA coordination team include researchers Hugh Coe and Saulo Freitas, of University of Manchester and INPE, respectively.