SNL cold open screen shot
'Cold Open' has come to be synonymous with Saturday Night Live. A bit of the weeks news is satirized by the cast until they blurt out "And live from New York, it's Saturday Night." Then it's on to an hour and a half of commercials, skits and music. Or, so I've been told. I'm usually asleep by then.
SNL's been hit or miss fun for fifty years now. But there's another 'cold open' that's been going on for much longer. That's the opening of the new year when the first few weeks of January are usually the coldest of the year.
Cold may be no laughing matter but you could almost make a joke that begins "A physicist and a meteorologist walk into a bar..." The two scientific disciplines see cold in slightly different ways. Physicist are more interested in heat which they define as a form of energy that exists as kinetic energy, or motion, in particles of matter. This energy tends to transfer from warmer objects to cooler ones. It may be what drives atmospheric circulation but the TV weathergirl who talks about "the kinetic energy of particles of matter" isn't going to last long.
January is cold, July isn't. A pond you're skating on is cold. A pond you're skinny dipping in isn't. Alaska is cold, Hawaii isn't. We all know what cold is. Or do we? I went looking for a simple scientific definition of cold. Silly me. A couple of physics books and some web research sent me down a rabbit hole into a world of thermodynamics, entropy and Bernoulli's Derivation of Boyle's Law. Believe me. You don't want to go there.
A physicist view of heat (or cold if the thing slows down)
A meteorologist's view of a cold front moving in
Just a little research into the concept of 'cold' convinced me there was book length material there. With cows to feed and diesel fuel gelled (by the cold), that sent shivers down my spine. Better to just pull together a potpouri of interesting items about cold while waiting for spring.
* Temperature measures how much energy an object has. There are three scales in common use: Fahrenheit, Celsius and Kelvin. Fahrenheit is the odd man out, mostly just used in the United States. A Celsius degree is the same as a degree Kelvin but the latter scale starts at absolute zero making it useful to scientist. Absolute zero is the bottom of the thermodynamic system where fundamental particles have almost no motion and no heat. It's 0º Kelvin, -273.15º Celsius or -460º Fahrenheit.
* There is a chilling list of 'coldest places'...
-The Boomerrang Nebula is oft cited as the coldest place in the universe at 1º K, -272º C and -458º F. Watch a short video here. Problem is, scientists in Germany have cooled matter to just a few trillionths of a degree above absolute zero. No word on how the Boomerrang is taking the news
Surprisingly, our Moon seems to harbor the coldest spot in the solar system with some of its polar craters bottoming out at -233 C. I wonder if this could have anything to do with the difficulty of getting a thermometer to Pluto's moons? Anyone want to volunteer for the job?
Pluto's moon Charon
* Finally, back on Earth, it's got to be Antarctica. For years the coldest temperature ever recorded was at the Russian Vostok Station with -128.56º F. More recently, several spots on the East Antarctic Plateau have been remotely measured at -138º F. In places where people actually live, Yahutsk in Siberia recorded -80.9º F last winter. Two other Russian cities, Oymyakon and Verkhoyanck have recorded -90º F with the average January temperature being -56º F. Then there's Hell, Norway which freezes over for a third of the year.
Unless you're standing next to a volcano (residual heat coming to the surface), solar radiation is what determines how cold/hot it is. Even those nefarious fossil fuels are just solar energy captured and preserved. The biggest factor in temperature is the angle at which the Sun's rays strike the Earth's surface and this is caused by the 23 degree tilt of our axis to the plane of rotation. Obliquity (tilt) is what gives us our seasons and it changes slightly in a 41,000 year cycle. Other Milankovitch cycles of axial wobble and orbit shape contribute to long term changes in average temperature and are probably what leads to periods of glaciation. There is even a Snowball Earth theory that at about 650 million years ago all the water on the planet was frozen solid.
Artist's rendition of Snowball Earth
(web image)
We experience hot/cold within the thin layer of gases called our atmosphere. I assumed that the higher you went the colder it got. Wrong again. In the lower reaches the temperature does drop at a rate of about 4º F for every 1000' of elevation gain. The coldest I've ever been was on top of Whiteface Mountain after skiing up the toll road. At the tropopause (6 miles up) the temperature might be -70º F but then it starts rising in the stratosphere to as much as 40º F. Another drop follows down to as low as -130º F at 50 miles in height before a dramatic rise into the thousands of degrees F.
(web image)
People live at the very lowest levels of the atmosphere and the weather and temperature there is what we notice. Some terms you may hear include:
- polar vortex- A large area of low pressure and cold air at the Earth's poles that weakens in summer and strengthens in winter. It has a counter-clockwise circulation and occasionally surges south over North America, Europe and Asia.
- Siberian Express - An extremely cold air mass that originates over Siberia and the Arctic Ocean before migrating into the upper US.
- radiative cooling - The emission of infrared radiation (usually at night) of energy absorbed from visible sunlight during the day.
(web image)
- water density - Water has the unique property of becoming more dense as temperature lowers to 39º F and then less dense as it freezes into a solid at 32º F. This is what causes lake 'turnover', makes for skateable surfaces and sinks large oceanliners when they hit floating icebergs.
(web image)
Finally, let's finish up with ways cold can get under our skin:
- Wind chill - How cold living things (people/animals) feel. As wind speed increases it feels colder as more internal heat is removed from the skin.
- Frostbite- This is when skin and tissues freeze causing damage. Read Maurice Herzog's account of having his fingers and toes snipped off after dropping his gloves on Annapurna and you will forever prioritize avoiding frostbite.
- Hypothermia - Medical emergency when your body temperature drops below 95º F. From prolonged exposure to low temperatures or relatively short immersion in cold water. Frozen Alive, an archived article from Outside, tells of a hypothetical case of hypothermia in medically accurate detail. Also related is the case of 16 Danish fishermen plucked from the sea after over an hour's dunking. They all walked across deck under their own power and were enjoying a hot drink when each of them keeled over dead. Obviously, it's a good idea to avoid hypothermia.
In a piece about cold it seems appropriate to let someone named Frost have the last word:
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