The simulation of SST, sea ice extents and ocean heat transports in a version of the Hadley Centre coupled model without flux adjustments

• Published in: Climate dynamics Vol. 16; no. 2-3; pp. 147 - 168
• Main Authors: GORDON, C, COOPER, C, SENIOR, C. A, BANKS, H, GREGORY, J. M, JOHNS, T. C, MITCHELL, J. F. B, WOOD, R. A
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.02.2000; Berlin Springer Nature B.V
• Subjects: Atmosphere; Climate change; Earth, ocean, space; Exact sciences and technology; External geophysics; Heat budget; Ice; Marine; Meteorology; Oceanography; Physics of the oceans; Sea ice; Sea surface temperature; Sea-air exchange processes; Simulation; Sea surface; Observation data; Numerical simulation; Surface temperature; Comparative study; Heat transfer; Sea ice; Ocean atmosphere interaction
• ISSN: 0930-7575; 1432-0894
• DOI: 10.1007/s003820050010

Results are presented from a new version of the Hadley Centre coupled model (HadCM3) that does not require flux adjustments to prevent large climate drifts in the simulation. The model has both an improved atmosphere and ocean component. In particular, the ocean has a 1.25 degree 1.25 degree degree horizontal resolution and leads to a considerably improved simulation of ocean heat transports compared to earlier versions with a coarser resolution ocean component. The model does not have any spin up procedure prior to coupling and the simulation has been run for over 400 years starting from observed initial conditions. The sea surface temperature (SST) and sea ice simulation are shown to be stable and realistic. The trend in global mean SST is less than 0.009 degree C per century. In part, the improved simulation is a consequence of a greater compatibility of the atmosphere and ocean model heat budgets. The atmospheric model surface heat and momentum budget are evaluated by comparing with climatological ship-based estimates. Similarly the ocean model simulation of poleward heat transports is compared with direct ship-based observations for a number of sections across the globe. Despite the limitations of the observed datasets, it is shown that the coupled model is able to reproduce many aspects of the observed heat budget.