Publication Date:
2012-03-26
Description:
Ocean biogeochemical models are routinely applied to assess the net global impact of ocean acidification and warming on pelagic CaCO3 cycling. As with respect to the net change of global air-sea carbon fluxes affected by the reduced calcification under future CO2 conditions, these models diverge by a factor of four. The standard method to evaluate modelled CaCO3 cycles is to compare alkalinity and CaCO3 saturation states with observations. In general, state-of-the-art models do feature strong deviations and it is unclear if, or to what extent, these are driven by a deficient representation of physics (ocean circulation) or a deficient representation of biogeochemistry. Here we apply the TA* method (developed to separates the signals of CaCO3 production and dissolution from the large, conservative alkalinity background in observations) to model output. The aim is twofold. First, to assess the method using additional explicit representations of preformed alkalinity, accumulated CaCO3 dissolution, and organic matter remineralisation. And second, we aim to disentangle deficiencies in the physical and biogeochemical module of an ocean biogeochemical model.
Type:
Conference or Workshop Item
,
NonPeerReviewed
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