Pollution from a Megacity in the Amazon: the Case of Manaus, Brazil

Fan, J., Pacific Northwest National Laboratory

Cloud-Aerosol-Precipitation Interactions

Cloud-Aerosol-Precipitation Interactions

Martin ST, P Artaxo, L Machado, AO Manzi, RA Souza, C Schumacher, J Wang, MO Andreae, HJ Barbosa, J Fan, G Fisch, AH Goldstein, A Guenther, JL Jimenez, U Poschl, MA Silva Dias, J Smith, and M Wendisch. 2016. "Introduction: Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5)." Atmospheric Chemistry and Physics, 16(8), 10.5194/acp-16-4785-2016.

Science

This special journal issue outlines the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) Experiment. The field campaign research sought to quantify how aerosol and cloud life cycles in a clean background in the tropics are influenced by pollutant outflow from a large tropical city. The team used ground-based research sites and aircraft measurement systems in wet and dry seasons in the environs of Manaus, Brazil for the study.

Impact

The experiment will enable the study of how aerosol and cloud life cycles, including cloud-aerosol-precipitation interactions, are influenced by pollutant outflow from a tropical megacity. The intended future legacy is that more accurate predictions, embedded in models, should be developed on how the present-day functioning of energy, carbon, and chemical flows in the Amazon basin might change, both due to global climate change and to past and projected economic development.

Summary

Published in a special issue of the journal Atmospheric Chemistry and Physics, the research outlined the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) Experiment, a field campaign that sought to quantify and understand how aerosol and cloud life cycles in a particularly clean background in the tropics were influenced by pollutant outflow from a large tropical city. The experiment was conducted by a large, multi-organization team, including scientists from the Department of Energy’s national laboratories, and was carried out in the environs of Manaus, Brazil, an isolated urban region of over 2 million people. There is natural forest outside the city for over 1000 km in every direction. The city, encompassing a large industrial zone, uses high-sulfur oil as its primary fuel for electricity generation and emits large quantities of soot. Particle concentrations increase 10 to 100 times in the pollution plume compared to when pristine conditions prevail. The intersecting research sites downwind of Manaus oscillated between one of the most natural continental sites on Earth and one in which the pollution emissions of a tropical metropolis interact with the natural emissions of the rain forest. These findings will help researchers understand how aerosol and cloud life cycles, including cloud-aerosol-precipitation interactions, are influenced by pollutant outflow from a tropical megacity. The goal is to provide data for a more accurate model of the Earth system to describe tropical regions and in particular the Amazon basin, where the hydrologic cycle is one of the primary heat engines of global circulation.