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EARTH SCIENCE > CRYOSPHERE > SEA ICE > ISOTOPES

Definition:
Isotopes are a form of an element with a certain number of neutrons, for
example carbon exists in three isotopes: C12, C13, and C14. Some isotopes are
naturally unstable and spontaneously decay at a fixed rate; other isotopes are
stable.


Reference:
Glossary of Ice Age Terms. http://academic.emporia.edu/aberjame/ice/gloss.htm