Hadley Centre Coupled Model Version 3
Project DescriptionHadCM3 (abbreviation for Hadley Centre Coupled Model, version 3) is a coupled atmosphere-ocean general circulation model (AOGCM) developed at the Hadley Centre in the United Kingdom. It was one of the major models used in the IPCC Third Assessment Report in 2001.
Unlike earlier AOGCMs at the Hadley Centre and elsewhere (including its predecessor HadCM2), HadCM3 does not need flux adjustment (additional "artificial" heat and freshwater fluxes at the ocean surface) to produce a good simulation. The higher ocean resolution of HadCM3 is a major factor in this; other factors include a good match between the atmospheric and oceanic components; and an improved ocean mixing scheme (Gent and McWilliams). HadCM3 has been run for over a thousand years, showing little drift in its surface climate.
HadCM3 is composed of two components: the atmospheric model HadAM3 and the ocean model (which includes a sea ice model). Simulations often use a 360-day calendar, where each month is 30 days.
Summer provided by http://en.wikipedia.org/wiki/HadCM3