permafrost

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Across
  1. 2. kaboom
  2. 5. pickaxe
  3. 7. where this is happening
  4. 8. people have discovered this with help from the permafrost
  5. 10. fart gas
Down
  1. 1. a _____ of ice
  2. 3. ice melting underground
  3. 4. the underworld
  4. 6. where this is happening
  5. 9. turns into water