minus-squareDerPlouk@lemm.eetoCollapse@lemmy.ml•In 1990, the US Navy predicted that the Earth would warm by as much as 4 degrees Celsius by 2040linkfedilinkEnglisharrow-up15arrow-down1·edit-21 year agoYou’ve converted the absolute value, not the delta. The quickest in your head conversion of a delta °C --> delta °F is to simply multiply by 2. +4°C --> +8°F To be accurate, remove 1/10th of the °C value before the multiplication. +4°C --> (4 - 0.4) = 3.6 —> +7.2 °F For absolute values, I personally do, for a quick ‘in your head’ approximation the other way round (°F --> °C) : remove 32 °F (78°F --> 46) divide by 2 (46 --> 23°C; I may stop there for a very rough approximation) add 1°C per decade (if you got 23°C, add 2°C --> 25°C; I usually stop there) add 0.1°C per unit (25 --> 25.5°C; it’s not the exact result but not too far) linkfedilink
You’ve converted the absolute value, not the delta.
The quickest in your head conversion of a delta °C --> delta °F is to simply multiply by 2. +4°C --> +8°F
To be accurate, remove 1/10th of the °C value before the multiplication. +4°C --> (4 - 0.4) = 3.6 —> +7.2 °F
For absolute values, I personally do, for a quick ‘in your head’ approximation the other way round (°F --> °C) :