I noticed again the other day that bottled water does not freeze in my deer stand.We had a night where it got down to 19f and high of 34 the next day, and then a night of 14f. I had two bottles of water in my deer stand, with sides of 1/2 inch plywood. Windows left open, 1 foot tall by 4 feet long, on all sides. Bottles were sitting on a 2x4 over the windows. Metal roof on the stand and the floor of the stand is 16 feet above the ground. This is not the first time that I have noticed that the bottled water does not freeze in pretty cold weather for Arkansas. Same brand of water froze in the bed of my pickup, with a cover on it. Puzzles me. miles
From your resident meteorologist: the air temperature 16' above the ground can be several degrees warmer than the air at the surface, particularly during the winter. In fact, it is USUALLY 3-4 degrees warmer at that height than at the ground during the winter. Google nocturnal inversion for reading pleasure.
Heck, let's have some fun with weather data trivia today.
1) when air temperature is reported at your local airport or National Weather Service Station, what height above the ground is the reading taken and why is it taken at that height?
2) why are wind speed and direction readings taken at 10 meters above the surface, rather than the same height that the temperature readings are taken?
It's easy to get water down to 32° but you have to cool it a lot more to make it into ice. So anything that could slow the cooling might keep enough heat in so it stays liquid. Works conversely too. You can get water to 212°F quickly but seems to take forever to boil. IIRC takes six times the heat to change 212°F water into steam than room temperature water to 212°F.
State changes are like that. They once made a hand warmer (probably still do) that had a salt in it. You put it into boiling water and it turned into a liquid and stayed liquid after cooling. Give it a sharp shocl ((plastic pouch had a metal disk clicker) and you could watch the liquid quickly change back to a solid. And it got uncomfortably hot while it did.
I've never seen anything like that before. Damn, you learn something new everyday. I wonder why it does that. If I remember correctly from school, I think the molecules need to get in line. That's why they say that hot water will freeze quicker or some such schit. The molecules are moving around more and get in line quicker.
I carry my water out there, so it's relatively warm. If it's real cold, my water bottle will begin to freeze before I'm done hunting that morning or afternoon in a couple of hours.
Heck, let's have some fun with weather data trivia today.
1) when air temperature is reported at your local airport or National Weather Service Station, what height above the ground is the reading taken and why is it taken at that height?
2) why are wind speed and direction readings taken at 10 meters above the surface, rather than the same height that the temperature readings are taken?
I'll take a stab at it, just for grins...
1) No idea at what height exactly, but off the ground enough to not have the ground temperature corrupt the air temperature?
2) To avoid deflection that may occur when wind hits the ground?
Had forgotten about that, you usually don't see that except in very pure water. Here's an explanation. There's also a converse corollary. Some years ago there was an Internet buzz about exploding microwaved water. Pure water was microwaved past the boiling point without actually boiling until a tea bag or something was put in the water. Then the excess heat was suddenly released as steam.
Weird stuff, water. Most solids are denser than the liquid and sink. If water did that every winter ice would form and sink to the bottom of the lake where insulated at depth it would never melt. Bad for fishing.
Had forgotten about that, you usually don't see that except in very pure water. Here's an explanation. There's also a converse corollary. Some years ago there was an Internet buzz about exploding microwaved water. Pure water was microwaved past the boiling point without actually boiling until a tea bag or something was put in the water. Then the excess heat was suddenly released as steam.
Weird stuff, water. Most solids are denser than the liquid and sink. If water did that every winter ice would form and sink to the bottom of the lake where insulated at depth it would never melt. Bad for fishing.
From that article.
Even if you don't apply pressure and don't add anything to the water, you can still have liquid water at temperatures below zero degrees Celsius. In order for water to freeze to ice, it needs something to freeze onto to start the process. We call these starting points "nucleation centers". In most situations, a little bit of dust, impurity, or even little vibrations in the water provide nucleation centers for the water to freeze onto. But if your water is very pure and very still, there is nothing for the water molecules to crystallize onto. As a result, you can cool very pure water well below zero degrees Celsius without it freezing. Water in this condition is called "supercooled". At standard pressure, pure water can be supercooled to as low as about -40 degrees Celsius. Supercooled water is kept from freezing only by the lack of nucleation centers. Therefore, once nucleation centers are provided (which could be as simple as a vibration), the supercooled water quickly freezes. Freezing rain is a natural example of supercooled liquid water. Once freezing rain hits an object on earth's surface, that object provides nucleation centers, and the rain freezes to ice.
It's a joke, son. Look up Carlin's "Hippy Dippy Weatherman" bit if you haven't seen it. Hilarious, must be on You Tube somewhere. Oh yeah.
Actually I know that when it's calm it's about 5 degrees warmer at the house owing to we're higher in elevation and heat island effect. So the app I wrote for the desktop that shows current conditions has meaning. Even though "current" conditions are updated only hourly.
Heck, let's have some fun with weather data trivia today.
1) when air temperature is reported at your local airport or National Weather Service Station, what height above the ground is the reading taken and why is it taken at that height?
2) why are wind speed and direction readings taken at 10 meters above the surface, rather than the same height that the temperature readings are taken?
I'll take a stab at it, just for grins...
1) No idea at what height exactly, but off the ground enough to not have the ground temperature corrupt the air temperature?
2) To avoid deflection that may occur when wind hits the ground?
I'm glad you wanted to play along and enjoy learning some trivia. And congratulations, you are partially correct in both cases - both of your reasons were considerations that were taken into account when developing the standards.
So, 1) temperature: Many of you Old-Timers may recall seeing the little white weather box stations back in the day that were located at airports and agricultural research farms, etc. Those boxes housed the instruments and were louvered to allow air flow to help keep the temperatures "honest" and not biased high. They were also the height of the typical person said that the person could walk up to them and open them up to take readings and make recordings without having to bend or stoop or use a ladder. Thus, this height eventually became the "standard" that is still be used on computer controlled automated stations today - approximately 4.5' heigh if I recall correctly.
2) winds: One of the primary focuses of collecting and reporting meteorological data has long been the support of of the aviation industry. It's one reason why the National Weather Service falls under the Department of Commerce. One of the most important pieces of meteorological information that a pilot wants to know is what the winds are doing near the surface just before his plane touches down. The wings on a typical airliner (generally-not exactly for every plane, obviously) are around 30-something feet above the ground just before touchdown. So, collaboratively with other countries and such, it was decided that 10 meters (since everyone else in the world uses the metric system) or 33 feet should be the standard recording height. (This did indeed help eliminate some of the bias with the wind's interaction with the ground due to friction.
Perhaps the container itself has just enough insulating properties to slow down the freezing properties?
Geographic location doesn't matter. If it's cold enough, it will freeze. Haven't you seen the movie Trading Places? The concentrated orange juice was not affected by the hard freeze in Florida.
This wild assed guess has no basis in science or firsthand knowledge.
I don't remember the answer to the temperature part but you have to measure wind some distance off the deck to avoid turbulence. Saw a good example of turbulence at the trap range, There are 40 ft. or so poplar at the archery range. When those poplar are upwind the little clay birdies dance even though those poplar look too far away to have any effect. Gotta shoot extra fast on those evenings.
One of the few things I learned at Iowa State, there is a mirre climate, and micro climate, or something like that. The one they report is at about four foot high, the other at ground level. It's colder close to the ground.
I don't remember the answer to the temperature part but you have to measure wind some distance off the deck to avoid turbulence. Saw a good example of turbulence at the trap range, There are 40 ft. or so poplar at the archery range. When those poplar are upwind the little clay birdies dance even though those poplar look too far away to have any effect. Gotta shoot extra fast on those evenings.
Yep. That's what my job as a meteorologist with our State's division of air quality does - model the interaction of air pollutant plumes with nearby buildings, terrain, and vegetation. Been doing that stuff for 30+ years now.
One of the few things I learned at Iowa State, there is a mirre climate, and micro climate, or something like that. The one they report is at about four foot high, the other at ground level. It's colder close to the ground.
Micro and macro, perhaps? My specialty is "boundary layer micro-meteorology".
I was disappointed along with thousands of others here locally when the NWS weather station at the regional airport failed during the hurricane in 2017.
You would think that they could get a formidable weather station to record vital information in an event like that.
Now that data is lost forever... Rainfall and wind speeds were all lost.
My specialty is "boundary layer micro-meteorology".
Might find this place interesting. To the west is prairie and hills left by glacier. Elevation drops quickly a couple thousand feet from 6 miles west of town to the SD/MN border 10 miles east. So the prairie weather gets moderated at the hills, and we're on the edge of systems moving up through Minnesota. We're typically warmer in the winter and cooler in the summer and miss most blizzards. Always fascinating to watch thunderstorms approach from the west, hit the hills and then slide around us, either to the north or south.
Then there was the winter we had snow with a strong wind riding down the hills to the west. Warmed the air enough to form freezing rain over about 20 miles of Interstate.Not forecast, the rest of the Interstate was good driving, but lots of cars in the ditch here.
NWS products have improved for here over the last decade. But a Fargo TV station has a degreed meteorologist who has been watching this area long enough to accurately forecast this area for all its quirkiness.
I have, many times,I also recall had bottled water which would be liquid but turn to slush if you shook the bottle. Same thing with soft drinks. I also recall watching water which was at 30 degrees but liquid, freeze solid around my water intake pipe. I remember this because it resulted in me having to carry water for 200 yards, on snowshoes, for 2 months (and another 3 months without the shoes) until the damn waterline thawed out. Good times. GD
I kicked a bottle of water out of a combine cab years ago. It bounced as high as the cab, it did not stop for several bounces' picked it up and read the label. "SPRING Water"
The bars in Angeles City used to cool their San Miguel beer in a salt and ice bath. Pop the cap, and watch the ice crystals form in a matter of seconds! Jerry
I usually keep a case of 24 bottled water in rear seat of my truck. I have found that different bottles freeze at different rates. When it is in the 20s for several nights some of the bottles will freeze solid, some totally liquid. Into the teens and a few more will freeze, some will stay liquid. Single digits almost all will freeze, but usually a couple will say liquid. Placement (whether they are in the outer ring or inner) doesnt seem to be a factor. Some will solidify when shaken, some will stay liquid when shaken. Always baffled me what the difference was that affected the temp they would freeze at.
Deer camp in Idaho this year, coldest morning was 3 degrees. It was a race when making coffee. Open the water bottle and dump as much into pot as possible before water freezes in bottle. Fun game early in the morning...I need a friggin wall tent...
There are several principles at work for this to happen. Air above the ground is warmer. Not necessarily much, but warmer. Latent heat of fusion takes more energy to freeze the water. Nucleation can be a significant issue with pure water. Lastly, as water cools it becomes denser until it hits 39.5 degrees. As it cools further it expands significantly. Depending on how long the water has been in the bottle and the temperature at which the water went into the bottle and the ambient temperature of it's storage, that expansion after passing 39.5 degrees F can pressurize the container and reduce the freezing point significantly. In all probability simply loosening the cap enough that the expansion will not build pressure will be sufficient to freeze the water and is a simple way the determine which properties are most critical to the explanation.
Supercooling (as low as -20 °C) of large volumes of water (up to 100 ml) for extended periods (as long as 100 days) simultaneously can be achieved by the surface sealing of the water by an oil phase [3233]. Many factors can cause supercooled water to crystallize, including vibration, particulate initiators, and neutrons but not electromagnetic irradiation [3402]. The freezing process, for supercooled water, takes place in two stages. The first stage produces a distinct peak of infrared emission (heat release) with the rapid but short-lived appearance of dendritic needles inside a spongy ice-water mixture [3638].. This is followed by the slower freezing of the bulk.
One obvious example of supersaturation are rain clouds. Seeding clouds provides a nucleation site around which supersaturated water vapor collects and makes rain drops. Saw this once as a kid and was pretty amazing. Heavy, grey clouds covered the area including the old steam powered wood mill a couple blocks away. The mill released a plume of black smoke which it did occasionally. Smoke found it's way to the clouds and very shortly thereafter there was a cloudburst type of downpour.
I kicked a bottle of water out of a combine cab years ago. It bounced as high as the cab, it did not stop for several bounces' picked it up and read the label. "SPRING Water"
I kicked a bottle of water out of a combine cab years ago. It bounced as high as the cab, it did not stop for several bounces' picked it up and read the label. "SPRING Water"
I thought surveyors at least had to be civil engineers. And in that, there'd be at least 2 semesters of chemistry and 1-2 semesters of physics, just in your B.S. undergrad.
My specialty is "boundary layer micro-meteorology".
Might find this place interesting. To the west is prairie and hills left by glacier. Elevation drops quickly a couple thousand feet from 6 miles west of town to the SD/MN border 10 miles east. So the prairie weather gets moderated at the hills, and we're on the edge of systems moving up through Minnesota. We're typically warmer in the winter and cooler in the summer and miss most blizzards. Always fascinating to watch thunderstorms approach from the west, hit the hills and then slide around us, either to the north or south.
Then there was the winter we had snow with a strong wind riding down the hills to the west. Warmed the air enough to form freezing rain over about 20 miles of Interstate.Not forecast, the rest of the Interstate was good driving, but lots of cars in the ditch here.
NWS products have improved for here over the last decade. But a Fargo TV station has a degreed meteorologist who has been watching this area long enough to accurately forecast this area for all its quirkiness.
I can appreciate a seasoned meteorologist who knows the local quirks. Forecasting is lots of science with some "art" thrown in.
I thought surveyors at least had to be civil engineers. And in that, there'd be at least 2 semesters of chemistry and 1-2 semesters of physics, just in your B.S. undergrad.
A liquid in any form can be in a state of super-cooled, this state is where the liquid is below it's freezing point but remains in liquid form. The more stable the liquid the longer it is able to remain in a super-cooled state.
