Im also a noob, I dove Dutch Springs at the end of summer and OMFG can you feel the water temp change. I think it was right around 40 feet if I remember correctly. I was looking down, saw the water shimmering....I was thinking ’thats odd’ and realized it was a thermocline. It literally felt like I had jumped into a cold pool, on a chilly morning. 53 degrees. I guess you could call it ’refreshing’.
Again, Im a noob and Im sure everyone here with any time underwater has experienced this phenomenon, but man was it unexpected.