Edad de hielo vs. glaciación
When discussing periods of extreme cold in Earth's history, Spanish distinguishes between pop culture and science. Edad de hielo is the colloquial phrase used in everyday life, while glaciación is the technical term preferred by scientists.
Edad de hielo
B1Literally translating to Age of Ice, this is the informal term for Ice Age. It is used in movies, fiction, casual conversation, and general knowledge contexts. It usually conjures images of woolly mammoths and cavemen rather than geological data.
A mis hijos les encanta la película La edad de hielo.
(My children love the movie Ice Age.)
Los mamuts lanudos son el símbolo más famoso de la edad de hielo.
(Woolly mammoths are the most famous symbol of the Ice Age.)
Hace tanto frío aquí que parece que estamos en otra edad de hielo.
(It is so cold here it feels like we are in another Ice Age.)
Los humanos tuvieron que adaptarse para sobrevivir a la edad de hielo.
(Humans had to adapt to survive the Ice Age.)
Glaciación
C1This word translates to glaciation. It is the formal, scientific term used in geology, geography, and climatology. It refers specifically to the process of ice sheets expanding or a specific period within a geological timeline.
La última gran glaciación terminó hace aproximadamente diez mil años.
(The last major glaciation ended approximately ten thousand years ago.)
Los científicos estudian el impacto de la glaciación en el nivel del mar.
(Scientists study the impact of the glaciation on sea levels.)
Durante una glaciación, los casquetes polares se expanden considerablemente.
(During a glaciation, polar ice caps expand considerably.)
El profesor explicó las causas astronómicas de cada glaciación.
(The professor explained the astronomical causes of each glaciation.)
Summary
If you are talking about the animated movie or casually mentioning the cold, use edad de hielo. If you are writing a geology paper or discussing climate cycles, use glaciación.