Fahrenheit and Celsius are the same

[paulbk]

Michael,
I believe Fahrenheit = Celsius at -40°. I'm an engineer. I've worked with this stuff for +40 years. But I would gladly forget all I know about engineering if I could take one photograph as good as any of yours. I'm convinced that all the practice in the world will not best a naturally gifted artful eye.
p

[wolfnowl]

You beat me to it, Paul.  -40 is the crossover.

When I was doing environmental work for a pipeline construction job, if the thermometer was below -35 deg C in the morning we wouldn't work because the equipment would freeze up, but if it was -32 with a -80 windchill, it was just another day.  Ben, you might want to add not letting your car go much below 1/2 a tank og gas or so or the moisture can crystallize in the tank and freeze the lines.  Carrying a six-pack of gas line antifreeze is always a good idea.  If, like my friend, you leave your vehicle unplugged when you go home from Christmas, you might, like he did, have to get someone to crawl under it with a torch to thaw out the block.  We won't even mention taking the spark plug from a snowmobile and heating it in a frying pan before reinserting it to get the engine to turn over!  Ah, such happy memories...  At least with digital we don't have to worry about static sparks on the film, or having the film get so brittle it just shatters.

Like Paul said, though - beautiful photographic work.

Mike.

[Paulo Bizarro]

Very nice article, with beautiful photos. Luminous landscape indeed...

I found it interesting reading, as the only experience I have in photographing in cold places was a trip to Moscow about 10 years ago in February. It was minus 25 degrees centigrade. I do have experience of photographing in the other extreme of temperatures, in the Empty Quarter of Oman. Different problems of course.

Again, a very enjoyable reading.

[michael]

Correct. -40C/F. But once the temperature drops below about -20C it's all academic.  

Michael

[fredjeang]

Correct. -40C/F. But once the temperature drops below about -20C it's all academic.  

Michael

So Canada is half of the year academic then!  

[John Camp]

Correct. -40C/F. But once the temperature drops below about -20C it's all academic.  

I know what you're saying...but I respectfully disagree...

In my experience, from 0C to roughly -20C, it's just cold and getting colder. From about 20C to -28C, it's bitterly cold, but with decent gear, you're okay. But once you're below about -30C (roughly -20F) you get into weird territory, where you can't depend on equipment to work like you expect it to...even winterized equipment, including stuff like steel. Clothing can actually break. The additional problem is, at those temps, you can die very quickly, even when you're not far from safety. I've gone safely cross-country skiing in the minus teens F, but I would hesitate to do that once it got below minus 20 F.

At the other end of the thermometer, everything can be handled safely until you get a few degrees above 100F, or 40C. But that seems to be the breaking point, and above 40C, again, things get weird. If you have strenuous travel at temps above 40, it seems (at my age, at least -- in my 60s) that I can't drink enough water to stay hydrated. I've actually got nauseous from drinking too much water at extreme high temps, but I need the water to stay hydrated.

I drove up to Deadhorse a few years ago, arriving right at the summer equinox, and took some of those shots of the sun not going down...not too creative, but interesting. I gassed up at Coldfoot Camp, and busted both a tire and a windshield along the way. That can all be handled. But the mosquitoes...I wanted to take some shots of salmon fishing on the Yukon, but even with headnets, you felt so harassed by the mosquitoes that it was hard to work. I'm not sure, but I think you could be killed by mosquitoes in Alaska. Has anybody ever heard anything like that? Just curious.

One of the best cheap trips in the world has to be the ferry from Alaska back to Seattle...

JC

[B-Ark]

Just a slightly different take on the subject - its not the temperature - its the wind.
I've hiked at -45 with no wind, and was so warm that I had to take my gloves off to keep from overheating.
And then, I've hiked at -2 with a very stiff breeze, and frozen my tailfeathers off.

I've done the Dalton and ANWR  in June/July and truly enjoyed the trip. I'd love to do it again in autumn (Sept/Oct?). Tundra colours can be both subtle and spectacular.

[Robert Roaldi]

That can all be handled. But the mosquitoes...I wanted to take some shots of salmon fishing on the Yukon, but even with headnets, you felt so harassed by the mosquitoes that it was hard to work. I'm not sure, but I think you could be killed by mosquitoes in Alaska. Has anybody ever heard anything like that? Just curious.

I don't know, but I am certain that they can drive you nuts and eventually convince you to kill yourself, because it's the least obnoxious alternative.

[wolfnowl]

I drove up to Deadhorse a few years ago, arriving right at the summer equinox, and took some of those shots of the sun not going down...not too creative, but interesting. I gassed up at Coldfoot Camp, and busted both a tire and a windshield along the way. That can all be handled. But the mosquitoes...I wanted to take some shots of salmon fishing on the Yukon, but even with headnets, you felt so harassed by the mosquitoes that it was hard to work. I'm not sure, but I think you could be killed by mosquitoes in Alaska. Has anybody ever heard anything like that? Just curious.

This is getting off topic, sort of, but a number of years ago a group of Canadian Wildlife Service biologists bared their arms and legs and had someone running around counting mosquitoes... the final tally was as many a 9,000 bites/ minute, which is enough to cause total exsanguination in roughly four hours.  Of course you'd go mad before then.  The bugs do cause caribou stampedes...

This is sort of related to photography because when the bugs are bad the only way you can make an image is to set the camera on a tripod, set the timer, walk away and have your personal cloud of mosquitoes come with you.  Personally I don't mind the cold that much!

Mike.

[Robert Roaldi]

This is sort of related to photography because when the bugs are bad the only way you can make an image is to set the camera on a tripod, set the timer, walk away and have your personal cloud of mosquitoes come with you.  Personally I don't mind the cold that much!

Yup, I'll take cold over bugs anytime.

[JeanMichel]

Michael,
I believe Fahrenheit = Celsius at -40°. I'm an engineer. I've worked with this stuff for +40 years. But I would gladly forget all I know about engineering if I could take one photograph as good as any of yours. I'm convinced that all the practice in the world will not best a naturally gifted artful eye.
p

Nope.
Minus 40 in either scale is balmy in my 'when I was your age I had to (insert horrible action) to school...
Or, "when I was your age I had to know the formula for converting Celsius to Fahrenheit, and know who came up with each scale and why, and if I did not know I had to look it up in some textbook or other. Today I felt lazy and simply entered 'Celsius, Fahrenheit, formula' in Google and voila:

Fahrenheit to Celsius: C= (F - 32) * 5/9


Celsius to Fahrenheit: F= (C * 9/5) + 32

 
Temperature Scales

The degree Fahrenheit (°F) is a unit of temperature named for the german physicist Gabriel Fahrenheit (1686 - 1736). In the Fahrenheit scale of temperature the freezing point of water is 32 degrees and the boiling point is 212 degrees placing the boiling and melting points of water 180 degrees apart. Zero degrees Fahrenheit indicates the lowest temperature Fahrenheit could obtain by a mixture of ice and salt.

The degree Celsius (°C) is a unit of temperature named for the Swedish astronomer Anders Celsius (1701-1744) who first proposed it. The Celsius temperature scale was designed so that the freezing point of water is 0 degrees and the boiling point is 100 degrees at standard atmospheric pressure. Since there are one hundred steps between these two reference points the original term for this system was Centigrade (100 parts).

Examples

How many degrees Celsius are 68 degrees Fahrenheit?
Replace Fahrenheit with 68 and solve for Celsius:
C = (68 - 32) * 5/9,
C = 36 * 5/9,
C = 20
20 °C = 68 °F

At what temperature are Celsius and Fahrenheit temperatures equal?
Replace both temperatures with "T" in one of the equations above and just solve for T:
T = T * 9/5 + 32,
-32 + T = T * 9/5,
-32 = T * 4/5,
-40 = T
-40 °C = -40 °F


HOMEWORK
Now class, without the help of any web based search engine or that of any high school student:
1. list all other temperature scales;
2. describe the uses of those scales;
3. explain colour (color for those who learned to spell south of my border) temperature.

Successful students will be permitted to gloat 'when I was your age....'

By the way, it is a fine 25 degrees C in my dungeon and I really should get back to paying work!

Jean-Michel

[PierreVandevenne]

In any case, one of the best recent article. Great pictures, enjoyable read. Thanks!

[Zerui]

Just a small scientific point.  Pure water freezes at -40° (C or F).  Ice melts at 0°C.
A brief explanation.  In order to freeze, water needs to contain an ice-like object that persists for long enough to accrete other water molecules from the liguid.
Pure water is a curious substance containing transient ice-like structures that last for longer when the water is colder.  At -40° C they persist for long enough to grow and form ice. So the water freezes.
Silver Iodide particles do the same at about -4°C  They are much used by weather mofication organisations as nucleation particles for freezing cloud droplets.
Clouds above the melting level in the atmosphere (0°C) comprise mainly super-cooled droplets.
Sorry about the lecturette. My PhD was in Cloud Physics in the early 1960s.  Best wishes, Zerui

[paulbk]

Just a small scientific point.  Pure water freezes at -40° (C or F).  Ice melts at 0°C.

Pure water freezes at 32°F (or 0°C). The triple point for water is very near the same temperature. Source: United States National Institute of Standards and Technology (NIST). Whether ice is melting or water is freezing depends on the current state and which way the latent heat of fusion is going. I'm not going to argue with you about nucleation sites or super cooled fluid. These are very unstable conditions.

[deejjjaaaa]

we still did not discuss the remaining 75% of scales

[Zerui]

I REPEAT:  Pure ice melts at 0°C.  Pure water freezes at -40°C. Water is in a state of supercooling when it is liquid at temperatures below 0°C. Weather on our planet would be very different if that were not the case. The physics of water is complex. It is not adequately described by classical engineering parametrizations such as a "triple point".  Zerui

[stamper]

It is fantastic what you can learn on a photographic site.