The Federation Aviation Authority limits how much dry ice can be on a plane because it releases carbon dioxide (too much can harm passengers and crew).

WSJ: How Would Santa Ship Chocolate Pears and Live Lobsters

Chile still has an unsettled border issue with Argentina, involving the limits of the southern Patagonian ice field.

BBC: Chile navy investigates 'xenophobia' in video

Speed skaters test human-performance limits--and smash records--with better training, better skates, faster ice.

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