Comments on: Boiling water turns into flash-frozen snow at -33C

By: Nathan Hornby

Nathan Hornby — Sat, 26 Jan 2013 14:42:00 +0000

“It all depends on how fast the cooling occurs, and it turns out that hot water will not freeze before cold water but will freeze before lukewarm water. ”

Good enough for me!

By: Paul Renault

Paul Renault — Sat, 26 Jan 2013 14:20:00 +0000

Not this again… ‘Not usually, but possibly under certain conditions.’:
https://www.scientificamerican.com/article.cfm?id=is-it-true-that-hot-water

By: Lurking_Grue

Lurking_Grue — Fri, 25 Jan 2013 22:58:00 +0000

Awesome… Still glad I am not in a place that cold.

By: Nathan Hornby

Nathan Hornby — Fri, 25 Jan 2013 18:18:00 +0000

“I doubt that boiling hot water, almost a gas energetically, is able to lose this much heat nearly instantaneously.”

FYI Boiling water freezes faster than room-temperature water.

By: Nathan Hornby

Nathan Hornby — Fri, 25 Jan 2013 18:16:00 +0000

Hopefully it was at least cold outside.

By: Nathan Hornby

Nathan Hornby — Fri, 25 Jan 2013 18:15:00 +0000

This was back in the day; 20,000 BC.

By: ratherbfishin

ratherbfishin — Fri, 25 Jan 2013 18:12:00 +0000

Mostly EVAPORATION. Check link below.
http://whyfiles.org/2011/ive-heard-of-people-throwing-boiling-water-in-the-air-on-cold-days-whats-happening-here/

By: Nathan Hornby

Nathan Hornby — Fri, 25 Jan 2013 18:12:00 +0000

“I personally disagree with people referring to the temperature as “-30″ when it’s really “-22 and windy” – those are not the same thing. You don’t dress the same for them…”

You certainly don’t. I live in a very windy place and on the odd day that the wind calms down it always feels so damned mild. You only have to go a mile inland and it feels like a totally different climate – on a windy day it’ll feel a lot milder, on a calm day it’ll be cooler (magic of a windy south-coast town). I live in the UK though, so it’s not ‘freezing’ as much as it is ‘meh’, but the effect the wind has should never be underestimated.

I hate the wind.

By: Nathan Hornby

Nathan Hornby — Fri, 25 Jan 2013 18:08:00 +0000

“If your ground is paved with a thick layer of aluminium” … as they often are.

By: showme

showme — Fri, 25 Jan 2013 16:33:00 +0000

You sure it wasn’t -40°C?

By: Xabaras

Xabaras — Fri, 25 Jan 2013 15:54:00 +0000

Nonna Maria needs to comment on this!

By: louisleblanc

louisleblanc — Fri, 25 Jan 2013 14:39:00 +0000

Mind you the very small droplets would lose heat very quickly to the air due to their large surface area with respect to their volume. Also the very large difference in temperature between the water and the air creates lots of convection increasing the heat transfer quite a bit. I tried it yesterday and it very well looked like snow, certainly solid by the time it hits the ground. I’ll try to get my boss to bring the high speed camera and shadowgraph outside today to try and get a better look at this.

By: Itsumishi

Itsumishi — Fri, 25 Jan 2013 13:46:00 +0000

True, but Phoenix was humid and raining this particular day.

By: Paul Renault

Paul Renault — Fri, 25 Jan 2013 12:52:00 +0000

Well, if your ground is paved with a thick layer of aluminium, that puddle’ll be ice in a few minutes.

By: Bakeca XincontriAdulti

Bakeca XincontriAdulti — Fri, 25 Jan 2013 07:16:00 +0000

This is awesome :D

By: Mike Fischer

Mike Fischer — Fri, 25 Jan 2013 04:08:00 +0000

I’ve been thinking very much the same thing this week as I’ve watched video after video of people creating large clouds of vapor and calling them snow. Where is the snow?!?

By: pjcamp

pjcamp — Fri, 25 Jan 2013 02:35:00 +0000

I was about to say that. It is not a temperature correction. If you set that pot of water on the porch instead of throwing it, it would reach a final equilibrium temperature of -25 C not -33 C. Wind can play a factor in how fast it reaches that equilibrium temperature but it has nothing whatsoever to do with the actual temperature.

Correcting the headline would be welcome. This is what comes of all those bananas in the same day.

By: Antinous / Moderator

Antinous / Moderator — Fri, 25 Jan 2013 01:02:00 +0000

Under 85° is cold to me. I wear my BB hoodie to go out to the mailbox in that weather. Super dry climates do make what you consider warm weather feel much cooler.

By: ryuthrowsstuff

ryuthrowsstuff — Fri, 25 Jan 2013 00:28:00 +0000

That’s really a bit depressing. I have a friend who travels quite a bit for work. This is the first thing he does after arriving in the frigid part of Alberta during winter time. I now associate the whole concept with Canada in general.

By: Itsumishi

Itsumishi — Thu, 24 Jan 2013 23:39:00 +0000

The actual temperature is on both the title of the video (the youtube video, not Cory’s title) and the description below the video.

As to your second question, no it needs to be well below freezing to achieve this affect. Remember the larger the difference in temperature, the faster the transfer of heat energy. Throw a pot of boiling water into the air at negative 2 celcius and you’ll end up with very hot water on the ground. An hour or so later you might have a frozen puddle.

By: Itsumishi

Itsumishi — Thu, 24 Jan 2013 23:36:00 +0000

I’m sure these are the only two people to have performed this experiment in the history of man.

In all seriousness though, the video you’ve linked to is very cool simply due to the from the ground camera angle.

By: Itsumishi

Itsumishi — Thu, 24 Jan 2013 23:33:00 +0000

I recently spent a few months in Toronto, then flew to Vancouver from Chicago via Phoenix, Arizona. It amused me a lot to hear the workers at Phoenix complaining about how cold it was at 68 degrees.

By: Antinous / Moderator

Antinous / Moderator — Thu, 24 Jan 2013 23:28:00 +0000

You must hate the dew point. But it’s the most useful measure in hot weather. Because evaporative cooling actually changes the temperature of your surface. As do the component parts of windchill, which are best summed up as ‘windchill’.

By: ratherbfishin

ratherbfishin — Thu, 24 Jan 2013 22:14:00 +0000

Is this really snow, as in the SOLID form of water? It looks to me like the water was merely dispersed to small droplets which then rapidly vaporized to the gas phase of water, which is invisible. You can see this as the cloud of “snow” rapidly dissipates rather than persisting or falling to the ground as snow or ice solids around 22-26 seconds. The snow where I come from doesn’t spontaneously disappear from sight. Further, even small amounts, around 1mL , of room temperature water may take several minutes to freeze in a -80C freezer. I doubt that boiling hot water, almost a gas energetically, is able to lose this much heat nearly instantaneously.

By: BillStewart2012

BillStewart2012 — Thu, 24 Jan 2013 21:43:00 +0000

I went to college in upstate New York, and there’d usually be a few weeks of -20F weather in the winter. A rumor that I can neither confirm nor deny says that residents of some of the dorms used to make snow the opposite way – they’d turn the showers in the dorm bathrooms on hot, and once it got steamy enough, they’d open the windows to let in cold air and make the snow there.

By: robotropolis

robotropolis — Thu, 24 Jan 2013 20:39:00 +0000

An acquaintance’s kid just found out the hard way to check the wind direction before trying this one.

By: Paul Renault

Paul Renault — Thu, 24 Jan 2013 20:30:00 +0000

OK, so now do they measure windchill, eh? Answer: the same way they measure relative humidity..

http://www.slate.com/articles/news_and_politics/explainer/2005/01/how_they_measure_wind_chill.html

Edited to add: ..it’s a human-skin thing only.” Yup, it only affect humans….not lambs nor sloths nor carp nor anchovies nor orangutans nor breakfast cereals, and not fruit bats nor large chu…

By: Amorette Allison

Amorette Allison — Thu, 24 Jan 2013 20:30:00 +0000

Tossing boiling water out the door when it is -40°F straight — no wind chill considered –used to be a popular pastime in my Montana town. Now we are lucky to get below freezing some days! Can’t even keep the outdoor ice rink frozen.

By: dragonfrog

dragonfrog — Thu, 24 Jan 2013 19:53:00 +0000

Human skin is governed by pure physics, just like other things. When there is a lot of air movement, warm surfaces don’t maintain a layer of warmer air near them (smaller delta-T between object & adjoining air), resulting in greater heat transfer. This applies to all warm objects, not just humans (that’s why the upwind side of a building is often colder than the downwind side).

I personally disagree with people referring to the temperature as “-30″ when it’s really “-22 and windy” – those are not the same thing. You don’t dress the same for them, objects without internal heating do not settle at temperatures below ambient, etc.

By: Chris Bollinger

Chris Bollinger — Thu, 24 Jan 2013 19:49:00 +0000

Windchill does mean something with pure physics. It is a relative measure of heat loss. Which means that it effects everything, not just human skin. The demonstration at hand happens in a short enough time frame that wind is not a factor, yes.