CMIP: a study of climate variability and predictability according to general circulation models

Coupled ocean-atmosphere general circulation models are used to predict future global changes, such as warming due to anthropogenic greenhouse gases (Houghton et al., 1996). In addition, coupled-GCM simulations of the natural climate (without human interference) can be compared with observations over the past century. Recent work along such lines concludes that an anthropogenic signal of global warming is emerging from natural variability `noise` (ibid.). More careful and systematic examination of the models seems warranted, however. Toward that end the World Climate Research Program has begun the Coupled ocean-atmosphere Model Intercomparison Project