Carbon Tetrachloride Emissions from the Amazon Forest

Kolby Jardine, Lawrence Berkeley National Laboratory, Earth and Environmental Sciences Area, Berkeley, United States, Jeffrey Q Chambers, University of California Berkeley, Department of Geography, Berkeley, United States, Kolby Jardine, National Institute for Amazon Research (INPA), Forest Management Laboratory, Manaus, Brazil, Angela B Jardine, INPA National Institute of Amazonian Research, Climate and Environment Department, Manaus, Brazil, Scot T Martin, Harvard University, Department of Earth and Planetary Sciences, Cambridge, MA, United States and Antonio O Manzi, Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil
Abstract:
As a chemically inert greenhouse gas in the troposphere with lifetimes up to 50 years but active in ozone destruction in the stratosphere, carbon tetrachloride (CCl4) plays a major role in the atmospheric chlorine budget and is widely considered strictly of anthropogenic origin deriving from numerous industrial processes and products. However, satellite remote sensing studies have shown higher concentrations at the Equator, and earlier work has suggested possible biogenic sources. Here we present highly vertically-resolved atmospheric gradients of CCl4 within and above a primary rainforest ecosystem from three towers in the Central Amazon. The observed buildup of CCl4 mixing ratios near the top of the main canopies provides new evidence for a potentially large biogenic source from the Basin. By demonstrating the need to represent tropical forests as biogenic sources of CCl4, our study may help narrow the gap between remote sensing observations of CCl4 and emission, chemistry, and transport models and therefore lead to improved predictions of its role in atmospheric chemistry and climate.
Back to: Anthropogenic-Biogenic Interactions Affecting the Atmospheric Chemistry and Physics over Tropical Rainforests I