Continuous measurements of atmospheric oxygen and carbon dioxide on a North Sea gas platform

摘要

A new atmospheric measurement station has been established on the North Seaoil and gas production platform F3, 200 km north off the Dutch coast(5°51' N, 4°44' E). Atmospheric concentrations of O₂ andCO₂ are continuously measured using fuel cell technology and compactinfrared absorption instruments, respectively. Furthermore, the stationincludes an automated air flask sampler for laboratory analysis of theatmospheric concentrations of CO₂, CH₄, CO and O₂ and isotopemeasurements of δ13C, δ18O and Δ14Cfrom CO₂. This station is the first fixed sea based station withon-site continuous O₂ and CO₂ measurements and therefore yieldsvaluable information about the CO₂ uptake in coastal marine regions,specifically the North Sea. This paper presents the measurement station andthe used methodologies in detail. In comparison to land-based stations, thedata show low day-to-day variability, as they are practically free ofnightly inversions as well as human influences, due to the station'sremoteness. Therefore, the data set collected at this measurement stationserves directly as background data for the coastal northwest Europeanregion. Additionally, the first data are presented showing the seasonalcycle as expected during August 2008 through June 2009. Furthermore, someshort-term O₂ and CO₂ signals are presented. The observations atthe platform include several large and fast changing negative atmosphericO₂ excursions without an accompanying change in the CO₂ signal,which most likely indicate marine O₂ uptake.