14 documents found, page 1 of 2
The Amazon Tall Tower Observatory (ATTO): Overview of pilot measurements on eco...
Andreae, Meinrat O.; Acevedo, Otávio C.; Araüjo, Alessandro Carioca de; Artaxo, Paulo; Barbosa, Cybelli G.G.; Barbosa, H. M. J.; Brito, Joel F.The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, and biodiversity. It has already been changed significantly by human activities, and more pervasive change is expected to occur in the coming decades. It is therefore essential to establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, and atmospheric cond...
Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, bore...
Yáñez-Serrano, Ana Maria; Nölscher, Anke C.; Bourtsoukidis, Efstratios; Derstroff, Bettina; Zannoni, Nora; Gros, Valérie; Lanza, Matteo; Brito, Joel F.Methyl ethyl ketone (MEK) enters the atmosphere following direct emission from vegetation and anthropogenic activities, as well as being produced by the gas-phase oxidation of volatile organic compounds (VOCs) such as n-butane. This study presents the first overview of ambient MEK measurements at six different locations, characteristic of forested, urban and marine environments. In order to understand better th...
CCN activity and organic hygroscopicity of aerosols downwind of an urban region...
Thalman, Ryan M.; Sá, Suzane S. de; Palm, Brett B.; Barbosa, H. M. J.; Pöhlker, Mira L.; Alexander, Michael Lizabeth; Brito, Joel F.; Carbone, SamaraDuring the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) campaign, size-resolved cloud condensation nuclei (CCN) spectra were characterized at a research site (T3) 60 km downwind of the city of Manaus, Brazil, in central Amazonia for 1 year (12 March 2014 to 3 March 2015). Particle hygroscopicity (κCCN) and mixing state were derived from the size-resolved CCN spectra, and the hygroscopici...
Observations of Manaus urban plume evolution and interaction with biogenic emis...
Cirino, Glauber G.; Brito, Joel F.; Barbosa, H. M. J.; Rizzo, Luciana Varanda; Tunved, Peter; Sá, Suzane S. de; Ji?enez, José Luis; Palm, Brett B.As part of the Observations and Modeling of the Green Ocean Amazon (GoAmazon 2014/5) Experiment, detailed aerosol and trace gas measurements were conducted near Manaus, a metropolis located in the central Amazon Basin. Measurements of aerosol particles and trace gases were done downwind Manaus at the sites T2 (Tiwa Hotel) and T3 (Manacapuru), at a distance of 8 and 70 km from Manaus, respectively. Based on in-p...
Influence of urban pollution on the production of organic particulate matter fr...
Sá, Suzane S. de; Palm, Brett B.; Campuzano-Jost, Pedro; Day, Douglas A.; Newburn, Matt K.; Hu, Weiwei; Isaacman-VanWertz, Gabriel A.; Yee, Lindsay D.The atmospheric chemistry of isoprene contributes to the production of a substantial mass fraction of the particulate matter (PM) over tropical forests. Isoprene epoxydiols (IEPOX) produced in the gas phase by the oxidation of isoprene under HO2-dominant conditions are subsequently taken up by particles, thereby leading to production of secondary organic PM. The present study investigates possible perturbations...
Long-term study on coarse mode aerosols in the Amazon rain forest with the freq...
Morán-Zuloaga, Daniel; Ditas, Florian; Walter, David; Saturno, Jorge; Brito, Joel F.; Carbone, Samara; Chi, Xuguang; Hrab? de Angelis, Isabella<p>In the Amazonian atmosphere, the aerosol coarse mode comprises a complex, diverse, and variable mixture of bioaerosols emitted from the rain forest ecosystem, long-range transported Saharan dust (we use Sahara as shorthand for the dust source regions in Africa north of the Equator), marine aerosols from the Atlantic Ocean, and coarse smoke particles from deforestation fires. For the rain forest, the coarse m...
Isoprene photochemistry over the Amazon rainforest
Liu, Yingjun; Brito, Joel F.; Dorris, Matthew R.; Rivera-Ríos, Jean C.; Seco, Roger; Bates, Kelvin H.; Artaxo, Paulo; Duvoisin, Sérgio JrIsoprene photooxidation is a major driver of atmospheric chemistry over forested regions. Isoprene reacts with hydroxyl radicals (OH) and molecular oxygen to produce isoprene peroxy radicals (ISOPOO). These radicals can react with hydroperoxyl radicals (HO2) to dominantly produce hydroxyhydroperoxides (ISOPOOH). They can also react with nitric oxide (NO) to largely produce methyl vinyl ketone (MVK) and methacro...
Strong sesquiterpene emissions from Amazonian soils
Bourtsoukidis, Efstratios; Behrendt, Thomas; Yáñez-Serrano, Ana Maria; Hel?en, Heidi; Diamantopoulos, Efstathios; Catão, Elisa Caldeira PiresThe Amazon rainforest is the world's largest source of reactive volatile isoprenoids to the atmosphere. It is generally assumed that these emissions are products of photosynthetically driven secondary metabolism and released from the rainforest canopy from where they influence the oxidative capacity of the atmosphere. However, recent measurements indicate that further sources of volatiles are present. Here we s...
Biogenic cloud nuclei in the central Amazon during the transition from wet to d...
Whitehead, James D.; Darbyshire, Eoghan; Brito, Joel F.; Barbosa, H. M. J.; Crawford, Ian P.; Stern, Rafael; Gallagher, Martin; Kaye, P. H.The Amazon basin is a vast continental area in which atmospheric composition is relatively unaffected by anthropogenic aerosol particles. Understanding the properties of the natural biogenic aerosol particles over the Amazon rainforest is key to understanding their influence on regional and global climate. While there have been a number of studies during the wet season, and of biomass burning particles in the d...
Atmospheric aerosols in Amazonia and land use change: From natural biogenic to ...
Artaxo, Paulo; Rizzo, Luciana Varanda; Brito, Joel F.; Barbosa, H. M. J.; Arana, Andréa A.; Sena, E. T.; Cirino, Glauber G.; Bastos, WanderleiIn the wet season, a large portion of the Amazon region constitutes one of the most pristine continental areas, with very low concentrations of atmospheric trace gases and aerosol particles. However, land use change modifies the biosphere-atmosphere interactions in such a way that key processes that maintain the functioning of Amazonia are substantially altered. This study presents a comparison between aerosol ...