Interannual sea–air CO2 flux variability from an observation-driven ocean mixed-layer scheme

[摘要] Interannual anomalies in the sea–air carbon dioxide (CO₂) exchangehave been estimated from surface-ocean CO₂ partial pressuremeasurements. Available data are sufficient to constrain these anomalies inlarge parts of the tropical and North Pacific and in the North Atlantic, insome areas covering the period from the mid 1980s to 2011. Global interannualvariability is estimated as about 0.31 Pg C yr⁻¹ (temporal standarddeviation 1993–2008). The tropical Pacific accounts for a large fraction ofthis global variability, closely tied to El Niño–Southern Oscillation(ENSO). Anomalies occur more than 6 months later in the east than in thewest. The estimated amplitude and ENSO response are roughly consistent withindependent information from atmospheric oxygen data. This both supports thevariability estimated from surface-ocean carbon data and demonstrates thepotential of the atmospheric oxygen signal to constrain ocean biogeochemicalprocesses. The ocean variability estimated from surface-ocean carbon data canbe used to improve land CO₂ flux estimates from atmospheric inversions.

[学科分类] 地球化学与岩石