Foreshadowing may play a role. There could be small hints early in the story about what will happen later, perhaps related to the characters' fates or their discoveries in Antarctica. This helps to build suspense and engage the reader.
Metaphor is likely used as well. The journey in Antarctica could be a metaphor for a journey of self - exploration. The characters might be on a physical journey through the ice and snow, but it really represents their journey to understand themselves better.