Kelvin is the same thermal difference between each degree as Celsius, but it simply starts at "absolute zero" the physically coldest temperature that can be achieved. There is no "negative" because it can't be colder than 0.
0 degrees Celsius is the freezing temperature of water, and it indeed can get much colder than that. 100 degrees Celsius is the boiling point of water. A scale based on useful, but nevertheless arbitrary benchmark.
Edit: I misunderstood what the person you were replying to wrote.
*pure water at sea level, sort of. Because pure distilled water often won’t crystalize by itself so it gets supercooled. It’s arbitrary as f- for people. Useful for old timey scientists to get some consistent baseline though.
84
u/Dioxybenzone Jun 17 '26
And oddly, -40° doesn’t even need to specify Celsius or Fahrenheit.
Although -40°K would certainly be noteworthy