Chemistry Reference
In-Depth Information
Fig. 1.
Research catamaran during 1997 Coastal Ocean Processes experiment.
The catamaran is shown here after deployment from R/V Oceanus in the North-
western Atlantic Ocean. The platform is manoeuvred autonomously and is con-
trolled remotely from the ship. During this experiment, the catamaran was
equipped to measure long and short wave spectra, sub-surface turbulence, chemi-
cal enrichment, and various meteorological parameters. A system to measure ver-
tical profiles of dimethylsulfide above the ocean surface was also incorporated
into the catamaran measurement suite
One of the most important findings of these studies and parallel labora-
tory efforts was that surface wave roughness (a parameter that can be re-
motely-sensed) was found to correlate well with gas-transfer rates across
the air-sea interface (Frew et al. 1995, Hara et al. 1995). Results obtained
in both laboratory and field experiments indicate that the range of wave-
lengths pertinent to gas transport may be restricted to wavelengths of mil-
limetres to centimetres. While the correlation between surface roughness
and gas transport is robust under differing environmental conditions, the
specific mechanisms of interfacial transport have yet to be adequately elu-
cidated and are the topic of recent research (e.g., McKenna 2004).
3 Mechanisms of air-water gas transport
The enhancement of air-sea gas transport (for waterside rate-controlled
gases), over that expected for pure molecular diffusion, is affected by sev-
eral interrelated mechanisms that can depend on the wind and wave condi-
