Today I found myself in a precarious situation. After discovering my emergency burrito had been eaten from the work freezer, I conducted an investigation. In that investigation I had to drink a cup of coffee in order to find out who made the pot of coffee. (Each person in the office brews a completely different pot using the same ingredients)
Once I tasted the coffee, I instantly knew this particular batch would be much better iced. But with only 4 ice cubes remaining in the tray I needed to get creative. If I added the cubes, they would melt and I'd suffer a sordid cup of room-temp bitterness. If I added my creamer first, it might help, but those cubes just wouldn't last as long as I desired.
Thankfully, a big part of weather is thermodynamics. This means all of my years of nerding would help me cool my cup in the best way possible.
Milk First or Ice
It's a dilemma we've all had, and interestingly enough, one the internet hasn't chimed in on. Thankfully, the answer is actually pretty simple.
First off, we have to establish a goal. The goal is twofold. First, we want a cold drink. Second, the most ice possible still in the cup— nobody wants their ice to melt, diluting the drink.
Now, water in it's states behaves differently. We are only concerned with the liquid and ice states for this article. And thankfully, the specifics of what we are concerned about can be simplified greatly.
What we want to know is how much energy it takes to raise the temperature of a substance by 1 degree. We then get a better idea of which ingredient will, in fact, do more cooling. It's easy to assume the ice, because it's colder– but that's not the case.
The specific heat capacity, or amount of energy it takes to raise the temperature of a specific substance by 1 degree, is greater for water in its liquid form than it is in its solid form. In fact, it's almost double. This means it takes double the energy (heat from your cup of coffee) to warm the creamer you pour into your coffee than it does to warm those ice cubes*.
So if your goal is the coldest possible drink with the least amount of ice meltage... add the creamer, wait, then add the cubes!
Want that cup even colder? Hate creamer? Don't want to mess with ice?
Don't worry there is another way to rapidly cool that cup-o-joe!
Simply grab a second cup and pour the contents of your first cup back and forth between the two cups until your desired temperature is reached!
(It'll happen a lot faster than you think) Simply by mixing in the cooler air you get the hot water to cool rapidly— more surface area is exposed to the relatively cold air.
You could also use a metal spoon to stir it for a slow, more controlled result.
Even blow on it, if you like spit in your coffee.
*Disclaimer– For simplicity sake, we are just assuming the creamer behaves like water. There are seemingly endless variables at play in each different creamer. Like sugar content, salt content (yeah there's salt in there), fat content... you name it!
For WeatherNation — Meteorologist Jeremy LaGoo