4 documents found, page 1 of 1
Molecular composition of organic aerosols in central Amazonia: An ultra-high-re...
Kourtchev, Ivan N.; Godoi, Ricardo Henrique Moreton; Connors, Sarah; Levine, James G.; Archibald, Alexander Thomas; Godoi, Ana Flávia LocateliThe Amazon Basin plays key role in atmospheric chemistry, biodiversity and climate change. In this study we applied nanoelectrospray (nanoESI) ultra-high-resolution mass spectrometry (UHRMS) for the analysis of the organic fraction of PM2.5 aerosol samples collected during dry and wet seasons at a site in central Amazonia receiving background air masses, biomass burning and urban pollution. Comprehensive mass s...
Airborne observations reveal elevational gradient in tropical forest isoprene e...
Gu, Dasa; Guenther, Alex B.; Shilling, John E.; Yu, Haofei; Huang, Maoyi; Zhao, Chun; Yang, Qing; Martin, Scot T.; Artaxo, Paulo; Kim, SaewungIsoprene dominates global non-methane volatile organic compound emissions, and impacts tropospheric chemistry by influencing oxidants and aerosols. Isoprene emission rates vary over several orders of magnitude for different plants, and characterizing this immense biological chemodiversity is a challenge for estimating isoprene emission from tropical forests. Here we present the isoprene emission estimates from ...
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...
Urban pollution greatly enhances formation of natural aerosols over the Amazon ...
Shrivastava, Manish K.; Andreae, Meinrat O.; Artaxo, Paulo; Barbosa, H. M. J.; Berg, Larry K.; Brito, Joel F.; Ching, Joseph; Easter, Richard C.One of the least understood aspects in atmospheric chemistry is how urban emissions influence the formation of natural organic aerosols, which affect Earth’s energy budget. The Amazon rainforest, during its wet season, is one of the few remaining places on Earth where atmospheric chemistry transitions between preindustrial and urban-influenced conditions. Here, we integrate insights from several laboratory meas...