Agreement of CMIP5 Simulated and Observed Ocean Anthropogenic CO2 Uptake

• Published in: Geophysical Research Letters
• Main Authors: Bronselaer, Benjamin, Winton, Michael, Russell, Joellen, Sabine, Christopher L., Khatiwala, Samar
• Other Authors: Univ Arizona, Dept Geosci, Geophysical Fluid Dynamics Laboratory; Princeton NJ USA, Department of Geosciences; University of Arizona; Tucson AZ USA, NOAA Pacific Marine Environmental Laboratory; Seattle WA USA, Department of Earth Sciences; University of Oxford; Oxford UK
• Format: Article in Journal/Newspaper
• Language: English
• Published: AMER GEOPHYSICAL UNION 2017
• Subjects: ocean carbon; CMIP5; anthropogenic carbon; impulse response function; observations; Indian; Pacific; Southern Ocean
• Online Access: http://hdl.handle.net/10150/626555; https://doi.org/10.1002/2017GL074435

Previous studies found large biases between individual observational and model estimates of historical ocean anthropogenic carbon uptake. We show that the largest bias between the Coupled Model Intercomparison Project phase 5 (CMIP5) ensemble mean and between two observational estimates of ocean anthropogenic carbon is due to a difference in start date. After adjusting the CMIP5 and observational estimates to the 1791-1995 period, all three carbon uptake estimates agree to within 3Pg of C, about 4% of the total. The CMIP5 ensemble mean spatial bias compared to the observations is generally smaller than the observational error, apart from a negative bias in the Southern Ocean and a positive bias in the Southern Indian and Pacific Oceans compensating each other in the global mean. This dipole pattern is likely due to an equatorward and weak bias in the position of Southern Hemisphere westerlies and lack of mode and intermediate water ventilation. NSF's Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) under NSF [PLR-1425989]; NOAA; NASA 6 month embargo; published online: 18 December 2017 This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [e-mail].