Scientists in Brazil are flying through the clouds around the city of Manaus. They collect data on how air pollution affects rainfall. With this information they hope to influence national climate policy.
This is a pyrgeometer. It sees infrared radiation, which means it measures temperatures at a distance. Infrared has longer wavelengths than visible light, so it’s invisible to us, but not to the pyrgeometer.
Image: ARM Climate Research Facility
Scientists measure temperatures and also look for aerosols – tiny atmospheric particles of pollution. They attach the pyrgeometer and 30 other sensors to an aeroplane and fly through clouds to study them.
The way clouds develop changes where they go, and how much rain they drop. The plant, animal and human life of the Amazon below depends on this rain.
Video: Flickr/Denise Mayumi
Researchers are exploring how aerosol pollutants affect the development of clouds, as there isn’t much information about this yet. They will collect data over 2014 and 2015 to build accurate climate models.
Scientists will use these models to predict what will happen to the Amazon in the future. This is important to increase our understanding of the human impact on the environment.
Paulo Artaxo is Professor of Environmental Physics at the University of Sao Paulo in Brazil. He investigates air pollution from the city of Manaus in the Amazon. I asked him about his work…
What are you researching?
‘I study how the Amazonian ecosystem works and how urban air pollution affects it. Pollution changes atmospheric properties like cloud formation, rainfall and photosynthesis. The GO Amazon project puts numbers to the human impact on the rainforest. We do this with atmospheric sampling equipment around Manaus, the only source of air pollution in an otherwise pristine rainforest.’
Why are you studying this?
‘Having grown up in Brazil, the health of our rainforests is very important to me, and to everyone. The tropical areas of the world are changing fast due to human interference. Life is becoming increasingly more urban, with people around the world moving to cities and expanding them. We need to understand how the ecosystem responds to these changes.’
What is significant about this location?
‘I study the air above Manaus and the surrounding rainforest – the “green ocean”. When you’re upwind of the city, the air is so clean it matches pre-industrial levels. But if you test clouds above the rainforest when downwind, you sense large quantities of aerosol pollutants. It’s this contrast between clean and polluted air that makes the area an ideal laboratory.’
What challenges do you face?
‘It’s not easy working in tropical forests. The ecosystem is far too complex for us to fully understand. Flying to Manaus from my home in São Paulo takes hours, so every small problem becomes a long and expensive trip for me. Also the high temperatures and humidity make life difficult for the instruments, computers, and for us!’
How is this work important?
‘Our work may reveal ways to delay climate change. If we don’t act quickly, global temperatures could sky-rocket this century, which would increase some climatic extremes such as floods, droughts or even hurricanes. This would have drastic economic and social impacts on future generations. I feel it’s our generation’s responsibility to avoid this as much as possible.’
What will be done with your research?
‘Governments need to preserve tropical forests with policies that are scientifically sound. Otherwise they will not survive economic pressures or changes in political systems. Governments, businesses and people in general have a great responsibility in helping to preserve tropical forests. Our research will help us know how to accomplish this.’
GO Amazon is an ambitious project, I asked some experts for their thoughts…
Damian Fleming, WWF
‘The Amazon rainforest is immense. It contains so much plant life that it effectively regulates the amounts of oxygen and carbon dioxide in the atmosphere. But it also strongly influences rainfall across Latin America, including areas that grow food for over half a billion people. I feel it’s critical to improve scientific understanding of climate processes.’
Monica Niermann, Planet First
‘Businesses share responsibility for the environmental challenges we face. There is growing demand in both developed and emerging economies for businesses to act on issues such as pollution. The use of data, from projects like GO Amazon, would encourage greener ways of doing things and show what we are doing towards getting cleaner air.’
Martin Sanzana Calvet, UCL
‘Cities such as Manaus are growing fast, which increases demand for public constructions such as roads and sanitation. Research shows large-scale urban and industrial development causes massive environmental damage. Manufacturing, transport, agricultural and energy industries also use scientific data to be more sustainable. Sharing this knowledge means governments can make better decisions that benefit everyone.’
Diana Mitlin, University of Manchester
‘I have visited Brazil before. The environment is more than just the rainforest. It is about safe places for children to play, clean water, sanitation and good air quality. Reducing urban poverty means improving access to these basic things. So with good urban planning, the government can improve people’s living conditions and help the environment too.’
This article was originally published as an interactive document in the Antenna gallery at the Science Museum.