High atmosphere-ocean Exchange of semivolatile aromatic hydrocarbons

B. González-Gaya, M.-C. Fernández-Pinos, L. Morales, E. Abad, B. Piña, L. Méjanelle, C.M. Duarte, B. Jiménez, J. Dachs
Nature Geoscience, 9, pp. 438-444, (2016)

High atmosphere-ocean Exchange of semivolatile aromatic hydrocarbons

Keywords

Atmospheric chemistry, Marine chemistry

Abstract

​Polycyclic aromatic hydrocarbons, and other semivolatile aromatic-like compounds, are an important and ubiquitous fraction of organic matter in the environment. The occurrence of semivolatile aromatic hydrocarbons is due to anthropogenic sources such as incomplete combustion of fossil fuels or oil spills, and other biogenic sources. However, their global transport, fate and relevance for the carbon cycle have been poorly assessed, especially in terms of fluxes. Here we report a global assessment of the occurrence and atmosphere–ocean fluxes of 64 polycyclic aromatic hydrocarbons analysed in paired atmospheric and seawater samples from the tropical and subtropical Atlantic, Pacific and Indian oceans. The global atmospheric input of polycyclic aromatic hydrocarbons to the global ocean is estimated at 0.09Tg per month, four times greater than the input from the Deepwater Horizon spill. Moreover, the environmental concentrations of total semivolatile aromatic-like compounds were 102–103 times higher than those of the targeted polycyclic aromatic hydrocarbons, with a relevant contribution of an aromatic unresolved complex mixture. These concentrations drive a large global deposition of carbon, estimated at 400TgCyr−1, around 15% of the oceanic CO2 uptake.

Code

Nature Geoscience, 9, pp. 438-444

Sources

Website PDF

See all publications 2016