A Fond Farewell to the Deep Cold

Yep. It's dang cold out there.

Cold enough to give an icicle frost-bite.

It’s spring! It’s spring! It’s spring! Tra-la-la-la-la!

Yes, spring temperatures have finally arrived in Edmonton after almost two weeks of January type weather stretching through the end of February and the beginning of March. I’m talking about lows of -29°C with a dollop of windchill on top, as Old Man Winter’s way of saying he’s not about to shuffle off quietly.

I have to admit to feeling somewhat trapped and claustrophobic going into  the last week of February with the weather forecast showing an unremitting deep freeze. Getting through the final freeze of the season is like slowly pedaling up a steep hill, while pulling a trailer filled with bricks, on a bike with under-inflated tires and with the brake pads rubbing on the rim. It takes me three times longer to layer up and get out the door. Furthermore, the commute is a slower one with added effort of moving my heaviest boots in circles, as well as the drag caused by the grease freezing in bike components. 

However, with a few years of Edmonton winter bike commuting under my belt, cycling through the deep cold has become just another routine. Properly prepared the riding can be comfortable and rewarding. 

In very cold weather, all the city buildings are sending out great plumes of condensing water vapour, as the moisture laden exhaust air from the hard-working heating systems mingles with the icy, bone dry air outside. The city looks like it’s on fire.

It doesn’t often snow when it’s very cold. There was a lot of brilliantly blue sky to be enjoyed. When it did snow, it was flurries of beautiful dry powder.

OLYMPUS DIGITAL CAMERAA real visual treat that you can sometimes spot during the deep cold are halos around the sun. These are caused as sunlight is reflected and refracted in tiny hexagonal ice crystals suspended in the air. On  one of my morning rides there was a faint haze of diamond dust crystals like a low-lying fog over the city. With the sun just over the horizon, a partial halo appeared in the form of two red and blue pillars flanking the sun. As I rode through Mill Creek ravine, an arc of halo seemed to spring directly up from the trees on the other side of the creek. It was like seeing the end of the rainbow. When I climbed back up to street level, depending on the conditions of light and shadow, the halo fragments sometimes seemed to be just a few feet away, but at other times to be as distant as the sun. Simply magical. Inevitably, my camera does not do it justice.

Ice Halo

Ice Halo

The coldest weather is hopefully now behind us, I’m looking forward to melting snow, bare asphalt and eventually speedy road bikes. With luck, I’ve donned my winter space suit for the last time this winter.

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Windchill & The Winter Cyclist

With the polar vortex instability this winter and the unusually cold weather our southern American neighbours have been experiencing, it’s not surprising that there has been a lot of chatter about windchill. A fellow Edmonton winter cyclist recently referred me to an article from Scientific American on the subject. The article contains some interesting facts about our bodies and how we perceive temperatures but incredibly seems to come to the conclusion that windchill isn’t real or useful value. I was pretty surprised to find this coming from Scientific American.

Windchill temperatures are an important consideration in a frozen country where your morning bike commute might be at -30°C with a brisk northerly wind. The sad truth is you can’t escape the first law of thermodynamics. It’s all about heat transfer. It can be a complicated subject but I’m going to address some of the basic facts.

Our bodies cannot measure temperature. You can’t stick your hand out the window and determine that it’s -28.5°C. It’s kind of similar to the fact that most of us mortals are not able to hear a musical note and determine that it’s A above middle C. With temperatures this means that we can only sense difference between the ambient temperature and the current temperature of the body part we’re exposing to the air (please be judicious in choosing the body part you expose). It’s like hearing two musical notes and being able to know the interval without knowing what the frequency of the notes are.

What our bodies actually sense is heat transfer: heat loss or heat gain. Mostly heat loss, actually. At about 37°C our body is almost always hotter than the surrounding air. Our chemical engine of a body is constantly producing heat that we need to get rid of.  If you ever find yourself in a situation where your body is actually GAINING heat  then you are in serious trouble – heat stroke is a life threatening emergency. On a hot summer day we are only able to slowly shed our excess heat and so we feel hot, on a cold winter day we are more rapidly losing heat and so we feel cold.

This is important when it comes to wind chill. Our sense of temperature is based on how fast we are losing body heat. On a windy day we lose heat faster, and feel colder.

This is why windchill calculations are used. For example, it might tell us that although the air temperature is -20°C, the wind will make us lose body heat at the same rate as if it were -30°C. This is a valid and useful piece of information for people who venture beyond the realms of house and car. The devil is in the details here, however, and determining that heat transfer equivalence  isn’t trivial. Most of the useful information in the Scientific American article speaks to this point.

The Scientific American article asks us to consider the dashboard thermometer of a car. Does it measure a different exterior air temperature when you drive faster? No, of course not, and so the the author dismisses the relevance of windchill. However, giving some consideration to the basic physics of windchill reveals this thought experiment to be flawed. True, the actual temperature of the air does not change as you vary the speed of your vehicle, but the rate at which your vehicle is losing heat IS changing with the airspeed. The vehicle is experiencing a windchill factor and the driver will have to crank up the heat in order to maintain a comfortable temperature inside the car. My house experiences windchill in this fashion – on a cold, windy night I turn up the thermostat, burn more gas and have a higher monthly bill as a result. One could imagine a specific windchill calculation for buildings. The heating engineers certainly already have one.

An unheated inanimate object will experience wind chill until it cools to the same temperature as the surrounding air. A cup of coffee left outside will cool quicker in the wind  than if there was no wind. The coffee will continue cooling until it’s the same temperature as the surrounding air and after that it doesn’t matter how hard the wind blows – the coffee is already at equilibrium. But until that point, you could do a wind chill calculation for the coffee cup.  If your human body reaches the same temperature as the surrounding air when it’s -20°C outside then it also cannot be affected by windchill – besides which, you’d be dead.

Considered from a cycling point of view it then becomes crucial to consider the wind direction when interpreting windchill temperatures. Suppose, Environment Canada tells me that it’s -20°C outside with a windchill of -30 and the wind is coming from the north a 18 kph. Lets consider three basic scenarios that might then happen during my morning commute.

First, if I pedal south at 18 kph then I am travelling at the same speed and direction as the wind and so I experience no windchill. I will only lose heat at a rate for the actual temperature of -20°C.

Second, if a red light causes me to sit unmoving on my bike at an intersection, then I am losing heat at the same rate as on a -30°C calm day.

Thirdly, if I suddenly remember that I forgot my lunch and then turn around head back north INTO the wind then I increase my windchill above the one in the forecast and I lose heat at even faster rate  – and I freeze my stem off if I’m not properly dressed.

I actually consider these factors when I leave the house to go to work each winter day and I use the information to choose my clothing.

 This is why the windchill temperatures are indeed relevant and useful information, and not a figment of a meteorologists imagination. It can be vital to know when you are moving around in dangerous temperatures.

You can read the Scientific American article that put the bee in my bonnet here:

http://www.scientificamerican.com/article/fact-or-fiction-is-wind-chill-real/

Coyotes & Songbirds

Winter Morning Ride

Winter bike commuting can be a very fine thing. If you were to head down to Mill Creek and conceal yourself in a snowdrift, and patiently wait, peaking out with a periscope, you just might spot me happily cycling past while whistling a jaunty tune or singing a song. On the other hand, you might not want to do that as the warble of this winter cyclist is often off-key. Despite the pleasures of commuting, it’s nice to actually get out for a purely recreational ride sometimes. On Saturday morning I finally managed to do this for this for the first time in a month.

The weather forecast had showed that Saturday was likely going to be the last of day of our two week long unseasonable thaw. We’ve had temperatures as high as +8°C when the normal temperature range for this time of year is between -18°C and -8°C. Knowing this gave me the necessary motivation to set my alarm for early Saturday morning. More importantly, it gave me the motivation to not press the snooze button a dozen times, ultimately ignoring the alarm, sleeping in and then annoying everyone around me by bemoaning the missed cycling opportunity. Shortly before dawn, I was out on the ravine bike and happily zooming down Kinnaird Ravine.

The thaw-freeze cycle has added a slick, icy crust to the boot-tromped, hard-packed snow on the trail. It’s probably treacherous to walk on, but it didn’t bother me much as I did my very best to let the studded tires do all the work. I did travel a bit slower than I normally would. I headed along the north side of the river towards the Capilano pedestrian bridge.

Winter Morning Ride

As I approached the bridge, I could hear some coyotes yipping somewhere ahead. Peering down the river, I thought I could see some shapes moving about on the ice. I rushed onward to get a better view. From the bridge I could see two coyotes scampering around on the river, chasing each other playfully. This was the high point of the ride, and I stopped to watch for a good 15 minutes, breaking out the thermos of tea as well. I tried to take a picture of the animals, but they were a fair distance away, and my rugged little point-and-shoot camera has wretched zoom ability.

Yes, those little black dots on the ice are coyotes. With effort, you can almost make out that they have legs.  National geographic photography awards, here I come!

Yes, those little black dots on the ice are coyotes. With effort, you can almost make out that they have legs. National geographic photography awards, here I come!

Also visible from the bridge, and equally majestic, was the Goldbar wastewater treatment facility that looked to be flaring off an excess of methane. Ah, the poetry of urban life!

Also visible from the bridge, and equally majestic, was the Goldbar wastewater treatment facility that looked to be flaring off an excess of methane. Ah, the poetry of urban life!

On the South side of the bridge, I headed back upstream and into some trails with a bit more climbing. There were a few comic moments along this segment. At a couple of spots I spun out and stalled out on a steep, icy climb and had to put my feet down…but it was too icy to walk or even stand easily. In the past I have been reduced to crawling to the side of the trail dragging my bike along. Today I was close enough to the crests to stand and lock the breaks, then use the bike as an anchor, shuffle ahead a few inches, then gingerly slide the bike ahead and repeat the process. Sheer cycling elegance, that’s my style.

Winter Morning Ride

Morning Winter Ride

Down in the riverside trails there was plenty of evidence of our recent unusually windy day. I will forgo my usual sneering at what Edmontonians think qualifies as a windstorm, and admit that it actually was pretty gusty that day.

Winter Morning Ride

Hmmm...should I bunny hop this obsatcle, shoulder my bike cyclocross style and hurdle it, or just heroically slink around it.

Hmmm…should I bunny hop this obstacle, shoulder my bike cyclocross-style and hurdle it, or just heroically slink around it.

As I was rolling along the path below the golf course, I startled a flock of little songbirds that flew up into the branches of a decrepit old tree and then started crying out a storm of protest at my intrusion. Suddenly suffering from an attack of a sort of digitally induced neo-pavlovian conditioning, I emulated a certain Langholm blogger and got out my camera and attempted to take a photo of the little birds. It turns out that this was actually really difficult to accomplish; the little creatures were in constant motion and my camera is at its worst in low light conditions. Once they decided I wasn’t some sort of bird-eating Sasquatch, they returned to feasting on the frost-wizened berries on the little stand of rowan trees. I found their choice of food to be a dubious one. The local rowan, or American mountain ash is, I think, the same species of tree that we call dogberry back on the east coast. Folks back there make a country wine using these berries. I’ve never yet had a drink of the stuff that I would describe as pleasant, though it certainly “does the job”.

Winter Morning RideAfter this, little of note happened during the ride (other than, ya know, exuberant enjoyment of the beautiful river valley trails and warm weather). I eventually headed back up out of the valley to city street level and headed off to Bikeworks to squeeze in some time at the shop before my family was up and about. The streets were a swampy slurry of water and slush covering lunar ridges of ice. Perfect conditions for creating roadway chaos when the temperature drops.

Winter Morning Ride

Twenty-four hours after taking this picture the temperature had plummeted from  +6°C to -16°C.

Twenty-four hours after taking this picture the temperature had plummeted from +6°C to -16°C.

Clinton’s Winter Cycling Lexicon

Local winter cycling veteran and fellow Bikeworks volunteer Robert Clinton has written a detailed lexicon naming the various snows and ices that winter cyclists encounter in Edmonton. There is also a heaping helping of winter cycling philosophy and  tips on dealing with these assorted conditions described. I’ve added this document to a new winter cycling tab at the top of my blog and I hope to add some photos of the various snows and ices at some point. Check it out if you ride in winter conditions, are thinking of doing so, or are just morbidly curious about the mindset that produces a winter cyclist. It’s a detailed treatise, so get a hot beverage before you settle down to read.

Winter Update : November 2013

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Idyllic winter riding.

This year November was a wintry month: from the early snowfall at the beginning of the month, to the subsequent sheets of ice, to the later heavy snowfalls. The river valley was blanketed with a heavy layer of beautiful, sparkling powder and there was some truly wonderful winter bike commuting. For a brief, but glorious time my trips to and from work coincided with stunning sunrises and sunsets. I was late for work two mornings in a row to due gawking at the sunrise. There was also a cold snap that lasted nearly a week with morning commuting temperatures as low as -24°C. That felt a bit unfair so early in the winter. I have lodged a formal complaint with the authorities.

The cold snap did allow the snow on the roads to be packed down into a hard surface resulting in easy cycling. Unfortunately, the following week the temperature was near or above the freezing point most days, causing all that lovely hardpack to loosen up into a deep morass of brownish, oatmeal-like snow. It stubbornly refused to repack, resulting in a weary week of paddle-wheeling my way to work. That kind of riding is actually pretty fun in small doses. A full week’s worth, on the other hand…not so much.

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The city crews had their hands full with the snow clearing. In one week alone we had more snow come down than we usually average for the entire month. Main roads were cleared only to be promptly buried again. The side roads mostly had to wait. Of course, a lot of my commute is on side roads. On the bright side, the multi-use trails were very promptly and consistently cleared.

I was very happy to see this notice on Thursday night. It refers to snow-clearing rather than something more sinister.

I was very happy to see this notice on Thursday night. It refers to snow-clearing rather than something more sinister.

My neighbourhood streets have now been well cleared of snow, just in time for the major snowstorm expected to hit tonight. Wheeeee!

The winter conditions wore me down a bit in November, and I spent very little time reading blogs and almost none writing them. In December I hope to be a bit more active. Also, as a new feature, there will be a series of guest blogs by Edmonton winter cycling vetran and EBC stalwart, Robert Clinton.

Pros and Cons of Winter Cycling

PRO: A Winter Wonderland!

PRO: A Winter Wonderland!

CON: Long stretches of pure ice.

CON: Long stretches of pure ice.

Yes, here we are again with a blog post inaugurating a new season of winter cycling in Edmonton. Saturday night’s snowfall transformed the landscape into a mix of winter wonderland and tortuously icy roads. I’ve been for a few rides in the new conditions and I think I’m getting my winter cycling mojo back a bit more quickly than last year. Of course, we haven’t yet had a really big snowfall yet, or a real blast of arctic temperatures…