Model metrics for the seasonal ocean pCO2 cycle

MUGLIA, JUAN; BRODY, SARAH; BRONSELAER, BEN; JOHNSON, LEAH; PILCHER, DARREN

Honolulu

Conferencia; 2014 Ocean Sciences Meeting; 2014

AGU-ASLO-TOA

Constraining processes that control the seasonal cycle of pCO2 in the surface ocean improve our understanding of the interannual variability of ocean pCO2 and the consequences for ocean uptake of anthropogenic carbon. Earth system models present a potentially valuable tool for understanding drivers of the ocean carbon cycle. However, before these models can be used for diagnostic and predictive purposes, it is essential to evaluate their ability to replicate the distribution and annual fluctuation of carbon at the ocean-atmosphere interface. This study assesses the ability of CMIP5 models to reproduce the seasonal cycle of surface ocean pCO2. A model skill metric is developed to account for characteristics of the seasonal cycle, the inhomogeneity of pCO2 observations throughout the global ocean, and the interannual variability of the modeled pCO2. This metric is then applied to different ocean biomes. We discuss how CMIP5 models vary in their ability to reproduce the seasonal pCO2 cycle and present the strengths and weaknesses of each model in capturing the spatial and temporal distribution of observed surface pCO2 in the world?s oceans.