title: Ocean acidification and marine trace gas emissions.
abstract: The oceanic uptake of man-made CO(2) emissions is resulting in a measureable decrease in the pH of the surface oceans, a process which is predicted to have severe consequences for marine biological and biogeochemical processes [Caldeira K, Wickett ME (2003) Nature 425:365; The Royal Society (2005) Policy Document 12/05 (Royal Society, London)]. Here, we describe results showing how a doubling of current atmospheric CO(2) affects the production of a suite of atmospherically important marine trace gases. Two CO(2) treatments were used during a mesocosm CO(2) perturbation experiment in a Norwegian fjord (present day: approximately 380 ppmv and year 2100: approximately 750 ppmv), and phytoplankton blooms were stimulated by the addition of nutrients. Seawater trace gas concentrations were monitored over the growth and decline of the blooms, revealing that concentrations of methyl iodide and dimethylsulfide were significantly reduced under high CO(2.) Additionally, large reductions in concentrations of other iodocarbons were observed. The response of bromocarbons to high CO(2) was less clear cut. Further research is now required to understand how ocean acidification might impact on global marine trace gas fluxes and how these impacts might feed through to changes in the earth's future climate and atmospheric chemistry.
authors.affiliation: Laboratory for Global Marine and Atmospheric Chemistry, School of Environmental Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, United Kingdom. fhop@pml.ac.uk
authors.forename: Frances E
authors.initials: FE
authors.lastname: Hopkins
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Turner
authors.forename: Philip D
authors.initials: PD
authors.lastname: Nightingale
authors.forename: Michael
authors.initials: M
authors.lastname: Steinke
authors.forename: Dorothee
authors.initials: D
authors.lastname: Bakker
authors.forename: Peter S
authors.initials: PS
authors.lastname: Liss
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis*; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D002980:Climate; D057231:Climate Change; D005740:Gases / Q000032:analysis; D017752:Greenhouse Effect; D006847:Hydrocarbons, Iodinated / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D009664:Norway; D009792:Oceans and Seas; D010839:Phytoplankton / Q000254:growth & development; D012623:Seawater / Q000032:analysis*; D013452:Sulfonium Compounds / Q000032:analysis
chemical_list: D005740:Gases; D006847:Hydrocarbons, Iodinated; D013452:Sulfonium Compounds; D002734:Chlorophyll; D002245:Carbon Dioxide; C027946:methylene iodide; C068078:dimethylpropiothetin; C014055:methyl iodide; D000077194:Chlorophyll A