General circulation model, a mathematical model of the circulation of the global atmosphere or oceans; (also) global climate model, a model of global climate (typically based on general circulation models).
noun
Mathematics
= greatest common measure.
Origin
1970s.
Definition of GCM in US English:
GCM
noun
Meteorology
General circulation model, a mathematical model of the circulation of the global atmosphere or oceans; (also) global climate model, a model of global climate (typically based on general circulation models).