Answer: In the context of oceans, thermal expansion is the increase in volume (or decrease. in density) of ocean water as a result of increased temperature of the water.
Explanation: But I'm guessing that you can find ocean expansion in any ocean? I mean... like it happens to EVERY ocean, not just one single ocean. So here are each of the oceans that ocean expansion might occur in: Arctic Ocean, Indian Ocean, Atlantic Ocean, Pacific Ocean, Meditarannian Ocean, and the Global Ocean.
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