Michael wme:Sea water can freeze, Fahrenheit set zero on his pioneering thermometer at that temperature (winter on a mountain top with acetone, the lowest he could get with the technology of the time. It is just a bit difficult to get it at sea level, but not impossible. North pole is sea level and sea ice – or at least still was the last time anyone checked.
Michael wme:Sea water can freeze, Fahrenheit set zero on his pioneering thermometer at that temperature (winter on a mountain top with acetone, the lowest he could get with the technology of the time. It is just a bit difficult to get it at sea level, but not impossible. North pole is sea level and sea ice – or at least still was the last time anyone checked.