I read these sentences in a chapter in my book which was Journey to the end of the Earth:
Either way, Antarctica is a crucial element in this debate - not just because it's the only place in the world which has never sustained a human population and therefore remains relatively pristine in this respect but more importantly because it holds in its ice- cores half million year old carbon records trapped in its layers of ice.
I can't help myself figuring out what the word "record" mean when used with carbon.