[hsartoris]

Edit: don't look at this reply, look at the answer with a direct citation from the article.

Almost certainly Fahrenheit. 32F is only the freezing point for pure water; most impurities reduce that. Now 27F is still pretty low, as most seawater freezes around 28F, but could be done no problem with the right chemicals. The key is making sure no areas have pure enough water to crystallize and expand, which is what destroys cells and other small structures.

[peterwoerner]

I thought 0F was the temperature the Baltic Sea froze at. Which is why Dr. Fahrenheit chose that as his zero.

[siberianbear]

That can't be right, because salt water freezes at a point a few degrees below fresh water. Now, 0F is defined where fresh water freezes.

[dpoochieni]

That's patently false, 0C fresh water freezes 0F a specific brine freezes