Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6337238 | Atmospheric Environment | 2016 | 7 Pages |
Abstract
The Amazon rainforest in Brazil and the megacity of Beijing in China are two of the most strongly contrasting habitats on Earth. In both locations, volatile chemicals are emitted into the atmosphere affecting the local atmospheric chemistry, air quality and ecosystem health. In this study, the total reactivity in air available for reaction with the atmosphere's primary oxidant the OH radical, has been measured directly in both locations along with individual volatile organic compounds(VOC), nitrogen oxides(NOx), ozone(O3) and carbon dioxide(CO2). Peak daily OH-reactivity in the Amazon 72Â sâ1, (min. 27Â sâ1) was approximately three times higher than Beijing 26Â sâ1 (min. 15Â sâ1). However, diel ozone variation in Amazonia was small (â¼5Â ppb) whereas in Beijing â¼70Â ppb harmful photochemical ozone was produced by early afternoon. Amazon OH-reactivity peaked by day, was strongly impacted by isoprene, and anticorrelated to CO2, whereas in Beijing OH-reactivity was higher at night rising to a rush hour peak, was dominated by NO2 and correlated with CO2. These converse diel cycles between urban and natural ecosystems demonstrate how biosphere control of the atmospheric environment is subverted by anthropogenic emissions.
Keywords
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Atmospheric Science
Authors
Jonathan Williams, Stephan U. KeÃel, Anke C. Nölscher, Yudong Yang, Yue Lee, Ana Maria Yáñez-Serrano, Stefan Wolff, Jürgen Kesselmeier, Thomas Klüpfel, Jos Lelieveld, Min Shao,