The Green Ocean Amazon Experiment (GoAmazon2014/5) Observes Pollution Affecting Gases, Aerosols, Clouds, and Rainfall over the Rain Forest

Abstract

The Observations and Modeling of the Green Ocean Amazon 2014–2015 (GoAmazon2014/5) experiment took place around the urban region of Manaus in central Amazonia across 2 years. The urban pollution plume was used to study the susceptibility of gases, aerosols, clouds, and rainfall to human activities in a tropical environment. Many aspects of air quality, weather, terrestrial ecosystems, and climate work differently in the tropics than in the more thoroughly studied temperate regions of Earth. GoAmazon2014/5, a cooperative project of Brazil, Germany, and the United States, employed an unparalleled suite of measurements at nine ground sites and on board two aircraft to investigate the flow of background air into Manaus, the emissions into the air over the city, and the advection of the pollution downwind of the city. Herein, to visualize this train of processes and its effects, observations aboard a low-flying aircraft are presented. Comparative measurements within and adjacent to the plume followed the emissions of biogenic volatile organic carbon compounds (BVOCs) from the tropical forest, their transformations by the atmospheric oxidant cycle, alterations of this cycle by the influence of the pollutants, transformations of the chemical products into aerosol particles, the relationship of these particles to cloud condensation nuclei (CCN) activity, and the differences in cloud properties and rainfall for background compared to polluted conditions. The observations of the GoAmazon2014/5 experiment illustrate how the hydrologic cycle, radiation balance, and carbon recycling may be affected by present-day as well as future economic development and pollution over the Amazonian tropical forest.

Power plant fuel switching and air quality in a tropical, forested environment

“…S3. The ozone plume spreads downwind from Manaus carried by the easterlies of the equatorial trade winds, in agreement with observations reported by Kuhn et al (2010) and Martin et al (2016Martin et al ( , 2017. The map shows that the pollution associated with Manaus emissions not only affects local air quality of the urban population but also reaches other regional downwind population centers, such as Careiro, Iranduba, and Manacapuru.…”

Elemental Mixing State of Aerosol Particles Collected in Central Amazonia during GoAmazon2014/15

“…The coatings of organics around the soot cores seen in this cluster are much thinner compared to other soot containing clusters which suggests that particles in this cluster are less aged [66]. The vast majority of particles from this cluster type are from site T3; given that T3 is downwind of Manaus, this suggests fresh urban soot emissions as this cluster's source [35].…”

“…The ZF2 site is located about 140 km directly downwind of the ATTO site. The final site, T3, is 70 km downwind of Manaus and often experiences the pollution plume from Manaus [34,35]. Site locations and characteristics are presented in Martin et al 2016 [34].…”

Overview: Precipitation characteristics and sensitivities to environmental conditions during GoAmazon2014/5 and ACRIDICON-CHUVA

“…The GoAmazon observations, collected over 2 years, have delivered a wealth of data on aerosol-cloudprecipitation (ACP) interactions . During the two intensive operation periods (IOPs) conducted during the wet and dry seasons, additional airplane data were collected by the IARA (Intensive Airborne Research in Amazonas), Martin et al (2017), and the ACRIDICON campaign . The data collected under the umbrella of the GoAmazon campaign also include the CHUVA project and several other initiatives, which have compiled the most complete dataset in Amazonas associated with atmospheric chemical and physical interactions.…”