Details

Autor(en) / Beteiligte

• Bronselaer, Benjamin
• Winton, Michael
• Russell, Joellen
• Sabine, Christopher L.
• Khatiwala, Samar

Titel

Agreement of CMIP5 Simulated and Observed Ocean Anthropogenic CO2 Uptake

Ist Teil von

• Geophysical research letters, 2017-12, Vol.44 (24), p.12,298-12,305

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2017

Link zum Volltext

Quelle

Wiley Online Library

Beschreibungen/Notizen

• 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 3 Pg 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. Key Points Observations and model simulations of ocean anthropogenic carbon assume different start dates Once referenced to the same period, 1971–1995, models and observations of ocean anthropogenic carbon agree to within 4% A model bias in the mean position of Southern Hemisphere westerlies results in a bias in the pattern of Southern Hemisphere carbon uptake