Limnology and Oceanography: Methods
A method for quantifying the diffusive air-sea exchange of gaseous organic carbon (OC) was developed. OC compounds were separated into two operational pools-those that were kinetically air limited in diffusion across the air-sea interface and those that were water limited-during simultaneous air/water sampling. The method separates OC compounds into low Henry's law constant (low-H) semivolatile OC (SOC) and high Henry's law constant (high-H) volatile OC (VOC) pools that can be categorized by relating diffusion kinetic parameters to Henry's Law constant. Air limited (low-H; H << similar to 0.1 L atm mol(-1)) compounds were collected in pure water traps and were quantified as dissolved OC, whereas water limited (high-H; H >> similar to 0.1 L atm mol-1) compounds were collected on solid sorbent tubes downstream from the water traps and were analyzed by gas chromatography-flame ionization detection (GC-FID). Separating OC based on H, rather than measuring OC as one bulk pool, allows improved estimates of OC concentration gradients and fluxes. A 10-month field study in the York River Estuary in Gloucester Point, VA revealed an average VOC flux of 138 µg C m-2 d-1 and an average SOC flux of 832 µg C m-2 d-1 (positive fluxes denote sea to air transfer).
Original Publication Citation
Hauser, E. J., Dickhut, R. M., Falconer, R., & Wozniak, A. S. (2013). Improved method for quantifying the air-sea flux of volatile and semi-volatile organic carbon. Limnology and Oceanography: Methods, 11, 287-297. doi:10.4319/lom.2013.11.287
Hauser, Emily; Dickhut, Rebecca M.; Falconer, Renee; and Wozniak, Andrew S., "Improved Method for Quantifying the Air-Sea Flux of Volatile and Semi-Volatile Organic Carbon" (2013). Chemistry & Biochemistry Faculty Publications. 139.