VON NEUMAN: CYBERNETICS AND CLIMATE CHANGE IN 1955

Climate models are older than generally realized.
The ones FORTUNE  credited in 1955 for   

"new meteorological understanding 
that may aid climate control"
ran on vacuum tube computers with 
hand-woven magnetic core memory

CORE MEMORY STILL WORKS, BUT A TERABYTE  WOULD  WEIGH A MEGATON

Kudos to William Connolley for resurfacing this blast from the past !