Working group Trace Gas Biogeochemistry

Dissolved gases play an important role in the field of Marine Chemistry for various reasons.

For the greenhouse gases methane and nitrous oxide, the marine environment acts as a net source for the atmosphere; for carbon dioxide, it is a strong sink for man-made emissions. The processes that control the cycle of all these gases are subject to changes, particularly in coastal waters, where primary production is increased by enhanced nutrient loads (eutrophication) and increased demand of oxygen changes the cycling of redox-sensitive gases like methane and nitrous oxide, bearing the potential of unwelcome feedbacks. The carbon cycle is the major link between primary production at the surface and oxygen-demanding mineralization in the interior, and the key to the understanding of biogeochemistry in the marine realm.

Other dissolved gases, though environmentally not that important, can provide valuable information for rates of important processes or transport mechanisms. Examples are the use of N2/Ar ratio to quantify nitrogen fixation or denitrification, or the use of artificial gas tracers to assess vertical mixing or ventilation.

The Working Group Trace Gas Biogeochemistry operates within all Research Foci of IOWs Research Programme:

- Process studies shed light on important key processes regulating trace gas production, decay and transport mechanisms (Research Focus 1).

- Basin-wide fluxes and metabolic rates, and potential changes on various time scales, are investigated through continuous and long-term observations, in particular through the use of our instrumentation on VOS Finnmaid (Research Foci 2 and 3).

- Through technical development, we seek to prepare the way for a better and cost-effective environmental monitoring matching societal needs (Research Focus 4, Cross Cutting Activity Innovative Instrumentation).

- Our research field includes the marine water column as well as the sediment-water and air-sea interface.