D&D 5E Can a Fireball melt ice FOR REALZ?

[Agamon]

I think the more important question is "Can jet fuel melt steel beams?"

The MOST important question is, "Can lava melt falling bodies?"

 

[Ahglock]

When I saw "Swan Lake on Ice", they set fire to the ice before the interval, then proceeded to skate on it during the second half. Given that the ice in question wasn't particularly thick, and given that the fire lasted considerably longer than a fireball, I'm going to say that no, a fireball doesn't melt any significant amount of ice.

And people probably have skated right through the wall of fire with no ill effects like how you can wave your hand through a camp fire. Since they don't pop out the other side looking like uncle Owen and aunt Beru after meeting storm troopers I'm gonna say not really the same thing.

If that's your GM call get great, all gms make calls like this. But I would ask what I ask myself before a ruling. Is my decision based on what I think is possible when I have little actual knowledge on the subject or based on what would be most fun? In this case people keep using well I used a torch to try and melt things. Hey awesome. But in any of these cases there are s few variables the 2 biggest are the heat of the flame and the material you are trying to melt. With one of the biggest variables missing as I have no idea how hot 8d6 fire damage is I really have no idea what would happen. So in that case I feel comfortable going for a it's melts to this point that is fun style answer. Heck if breaking logical possibilities would be more fun I'd do that but I GM for too many science types to pull that off well.

Let's say they are trying to melt a ice wall to get into or out of a cave complex. Is there a reason they shouldn't get through it? If yes it's deceptively thick and while you are making progress it's going to take a lot more fireballs and plot hours to break through. Doable sure because if the players want out or in I'll wing it, but I'll give them a hint it's not a planned route. If I don't care if probably have it weaken but not break. And then the barbarian might make a strength check to shatter the now weakened ice wall. If I really wanted them then to break through anyways the thickness is such that it melts and then collapsed under its own weight.

All that being said. Every GM style is different and if people are having fun you are doing it right.

For cases like this I focus on things like this.

1. What would be the fun answer?
2. Am I being consistent. If not people usually stop having fun.
3. Is it absurd? Is it really absurd or am I just saying no because I don't think someone can do that physically? This usually comes up for more mundane things, it would be impossible to sneak here, or climb that, or maneuver past it. 99% of the time reality shows ordinary non dragon fighting humans actually being capable of what is think is impossible. So was it real and I mean really absurd and impossible?
4. Say go for it, roll them dice no that's impossible sucks to hear IMO.

I suck at a lot of things as a GM, I'm terrible at describing combat encounters past the numbers, I don't put in enough social scenes and my npcs have a narrow range of what I pull off well. But I'm pretty happy with how I pull off the I'm gonna melt the ice bridge with my fireball attempts. Though my style there may suck for some people and their groups.

 

[Mercule]

When I saw "Swan Lake on Ice", they set fire to the ice before the interval, then proceeded to skate on it during the second half. Given that the ice in question wasn't particularly thick, and given that the fire lasted considerably longer than a fireball, I'm going to say that no, a fireball doesn't melt any significant amount of ice.

For things like gasoline (and assuming whatever they used was in the same basic ballpark), it's actually the fumes that burn, not the liquid. That means the flame is actually slightly above the ice, not directly on it. Yes, there will be radiant heat that hits the ice and some melting will occur, but most of the heat will rise. Eventually, the ice would all go away (assuming sufficient fuel), but it's not quite the same thing as a fireball.

There are also a number of substances that burn relatively cool, many alchohols and acetatates, IIRC. It's been years and years since I was a chemical engineering undergrad (I'm now a computer programmer), but I do remember there being a lab where an idiot TA dipped his hand into something and lit it up, letting it burn until the fuel was gone. I don't think the flame was bright enough for a stage show, but it proves the theory.

 

[Lanliss]

Depending on the amount of ice, I would say yes or no. What some are not including is the "explosion" of the fireball in their equation. Can a fireball melt a 10 foot x 10 foot block? I would say no. However, it could shatter the block, if it meets the damage requirements. As they say, there is more than one way to destroy a giant block of ice. It doesn't have to melt.

 

[Tony Vargas]

To me the more interesting question is: What do you do when the DM and player disagree on what should happen?

The DM narrates what happens.

 

[Khisanth the Ancient]

How long would a glacier last if thrown into the sun? Is a fireball as hot as the sun? I doubt it, but it's also probably many many orders of magnitude hotter than a campfire or torch or whatever real world example used so far.

Well, technically, the sun is only one order of magnitude, or less, hotter than a campfire. The sun's surface is about 5800 Kelvin, and 580 Kelvin is only about 585 F. I don't know exactly how hot a campfire is, but definitely hotter than that, because I've seen reenactors melt lead over one to to make bullets.

And torches are not just wood but treated with other stuff, so probably burn hotter.

 

[AaronOfBarbaria]

...I don't know exactly how hot a campfire is...

Typically around 1,570 degrees Fahrenheit. That's about 1,128 Kelvin.

 

[Psikerlord#]

Not all ice is created equal. The thinner/more fragile the ice the more likely it will be susceptible to quick bursts of heat. A delicate ice sculpture might suffer some deformity but a wall of ice 5' thick might barely do anything other than get a bit more slippery from such a blast.

this!

 

[Ahglock]

Well, technically, the sun is only one order of magnitude, or less, hotter than a campfire. The sun's surface is about 5800 Kelvin, and 580 Kelvin is only about 585 F. I don't know exactly how hot a campfire is, but definitely hotter than that, because I've seen reenactors melt lead over one to to make bullets.

And torches are not just wood but treated with other stuff, so probably burn hotter.

Lol. Okay if you take my statement literal instead of figuratively as I intended I'll point out I did not specify the surface of the sun. The center reaches around 10 million degrees. Since its been 20+ years since I've had to work out math like that I won't try to figure out exactly how many orders of magnitude that is I think 3 orders 4 if we assumed 1000 degrees for the campfire instead of the 1500 below. But my memory sucks so I may be wrong.

Still my point stands. I've seen people fall into campfires and while they were burned it wasn't that severe due to wearing decently heavy clothes. A fireball is hot enough to turn them into a charred corpse. So a fireball actually might be as hot as the surface of the sun. And with its volume it does have a fairly large thermal mass at least compared to a campfire or torch.

 

[Khisanth the Ancient]

Lol. Okay if you take my statement literal instead of figuratively as I intended I'll point out I did not specify the surface of the sun. The center reaches around 10 million degrees.

A good point, but a piece of ice (or anything else) dropped into the sun wouldn't survive to reach the deeper layers

Still my point stands. I've seen people fall into campfires and while they were burned it wasn't that severe due to wearing decently heavy clothes. A fireball is hot enough to turn them into a charred corpse.

That's true... OTOH presumably those people weren't completely engulfed in fire.

A fireball is definitely hotter than a campfire, especially since it's brief.

But it doesn't melt metals, so that sets an upper limit, IMO. The actual temperature of the fireball might be above the melting point of, say, copper but the heat transferred isn't enough to raise the metal temperature high enough + provide the heat of fusion.

And the heat of fusion of water is *really high* even though the melting point is low.