Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 1 1 2004 10.5194/bg-1-101-2004 http://www.biogeosciences.net/1/101/2004/ http://www.biogeosciences.net/1/101/2004/bg-1-101-2004.html http://www.biogeosciences.net/1/101/2004/bg-1-101-2004.pdf 101 111 2004-11-16 Coastal upwelling fluxes of O₂, N₂O, and CO₂ assessed from continuous atmospheric observations at Trinidad, California T. J. Lueker Scripps Institution of Oceanography, UCSD, La Jolla, CA. 92024-0244 USA Continuous atmospheric records of O₂/N₂, CO₂ and N₂O obtained at Trinidad, California document the effects of air-sea exchange during coastal upwelling and plankton bloom events. The atmospheric records provide continuous observations of air-sea fluxes related to synoptic scale upwelling events over several upwelling seasons. Combined with satellite, buoy and local meteorology data, calculated anomalies in O₂/N₂ and N₂O were utilized in a simple atmospheric transport model to compute air-sea fluxes during coastal upwelling. CO₂ fluxes were linked to the oceanic component of the O₂ fluxes through local hydrographic data and estimated as a function of upwelling intensity (surface ocean temperature and wind speed). Regional air-sea fluxes of O₂/N₂, N₂O, and CO₂ during coastal upwelling were estimated with the aid of satellite wind and SST data. Upwelling CO₂ fluxes were found to represent ~10% of export production along the northwest coast of North America. Synoptic scale upwelling events impact the net exchange of atmospheric CO₂ along the coastal margin, and will vary in response to the frequency and duration of alongshore winds that are subject to climate change.