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This Winter, explained.

Categories: Midd Blogosphere

Some of our winter weather is controlled by a weather oscilliation know as the North Atlantic Oscilliation, or NAO. This is defined by the difference in atmospheric pressure between an area above Iceland and above the Azores. Ordinarily, low pressure in the winter sits over Iceland, and high pressure over the Azores, and this creates the Polar Vortex, which is simply wind and weather spinning counter-clockwise around the north pole. Picture the two pressure systems as gate keepers, keeping the cold wind spinning around the pole. This strong low pressure over Iceland also draws air from the south west across Eastern North America, giving us somewhat more mild air. Weather scientists call this a teleconnection, or linking of pressure systems across broad geography.

This winter, extraordinary high pressure sat over Greenland, matched by high pressure over Alaska. This caused a breakdown in the polar vortex, causing cold arctic air to dump southward, on top of us. This cold air spilling south is replaced by warmer continental air. A similar event happened last winter as well. Scientists are blaming our colder than normal temperatures and our increased precipitation on this unusual pattern.  Much research is taking place now on this event, known as a Warm Arctic/ Cold Continent.

Average Pressure Pattern

High Pressure, February 2010

The reason for this is a disturbing lack of arctic ice. In January, there was a record setting amount of missing ice in the Arctic, about twice the size of Texas. In the summer, more heat is absorbed by the ocean, which releases in the fall, warming the air above and causing the high pressure. Ocean temperatures are well documented to influence weather patterns, such as the El Nino events, or even hurricane patterns in the Atlantic ocean. And most weather researchers are laying the blame of the lack of arctic ice right at the feet of global warming.

This weather pattern has been breaking down the last couple of weeks, as low pressure is forming in the arctic, creating more sea ice, keeping the cold air locked in the polar vortex. It may be that the groundhog was correct, and our exceptionally snowy and cold winter may be coming to an end.

Winter Carnival-Snow Sculptures

Categories: Midd Blogosphere

There is a lot more to snow sculpting than meets the eye. Our department does quite a few things, but probably one of the most unusual is making giant blocks of snow for the annual Winter Carnival snow sculpture contest.

Not this year, obviously, but some years the primary ingredient can be a little tricky. I’ve heard stories of past years: hauling snow from breadloaf, or moving it from Kohn Field. This year, we merely pushed snow up in piles right out in the quad near where we need them. Didn’t even have to push from any sort of distance.

We start with the box itself. Hopefully you’ll get a feel for the size from the picture-it’s about 7′ tall and about 6′ wide. 4 panels mate together, and then are held by ratchet straps.

We then start some mixing. Yes, with a backhoe. We’re talking quite a bit of snow here. By adding water to a fluffy snow it packs better, like the perfect snowman snow you used to wait for growing up. We blend it until it is about the consistancy of mashed potatoes. Some years this part of the process is miserable, what with the cold and all. This year, the day started in the teens, but quickly warmed into the upper 30′s.

Next, we start adding the snow to the molds. I’ve always been a big fan of the power of hydraulics, never more so than figuring out how to get several yards of snow 8 feet up in the air.

The snow gets placed into the molds in what civil engineers call ‘lifts’, or many individual layers each compacted to remove air pockets. This is a pretty important step. We work about 1′ of snow at a time, and carefully fill the edges of the crate, and use a tamper across the entire surface. Student volunteers are very helpful at this stage-that’s Grace (I never got her last name), she’s the organizer of the competition this year, working with Brian Paquette from our landscape department. And yes, that’s me behind the camera, not avoiding work, I took the next turn.

We fill the boxes to the top, wait for them to set up for a little bit, then take the ratchet straps off and move the contraption to the next location. This year we made 5 snow cubes, as only 5 teams entered. Then, later during winter carnival, the students have at it. We supply shovels, ice scrapers, and other implements of mass destruction.

Here’s one of the teams. Like I said, it was warm that day. This team wouldn’t tell me what they were making at the time. I had no idea the competition was so cut-throat. I came back briefly to campus over the weekend to photograph the finished sculptures, and, like most years, was impressed by the creativity. I never seemed to have progressed past snowman, or feeling expansive occasionally, snow fort.

This was what the team above made, couch and tv set. I’m hoping the antenna for the tv came from the ground, not a live tree.

One of my kids liked the ice cream cone best. It was about 10 degrees outside when taking this picture, so maybe this inspiration came from the middle 50′s of the previous day.

I liked the idea of the mini-Mead Chapel right below the larger version.

We don’t know what this is. Cobra head? Squirrel tail? Modern snow?

This was the winner, both by Grace the judge, and by my kids (not that they had any say in the matter.) Wine and cheese, obviously. Pretty cool.

Putty Knives

Categories: Midd Blogosphere

A couple of storms ago, I caught myself absentmindedly sticking our most important snow fighting tool into my pocket, and it occurred to me I’d left it out of the list of techniques and equipment I’ve written about in the past. Yes, for some storms, the most important tool in our kit seems to be the lowly putty knife. I prefer an inch and half blade myself.

I was introduced to this my first winter at Middlebury, during the Valentine’s day storm of 2007. The roads were impassable- I’d tried with a friend in a four wheel drive truck, and we’d turned around and went back to the college to spend the night. This was no ordinary storm, but a a blizzard, so strong we couldn’t keep up with it, either by shovel, tractor, or plow. The most important work of the night remained, though, so we broke into teams of two or three, shovels and putty knives in hand, and trudged from building to building, closing doors.

A plumber told me Middlebury has 110 buildings. I asked him how many exterior doors were on campus, and got a look like I’d lost my mind. Fire codes dictate at least two per building, and some many, many more, so let’s say there is 500. Most of these buildings are heated centrally with steam, from the Service Building. The operators in there work wonders, 24/7, heating the entire campus. Ever had snow block your main door at your house, preventing it from closing? Even if you don’t notice immediately, I bet you quickly figure it out as the draft quickly goes through the house. Some storms seem block doors better than others. Now imagine if even a couple of doors on campus are like that. The magicians in the heating plant notice. Now imagine those storms where even 10% of the doors are stuck part way open. The steam can’t compete,alarms in the plant go off, and precious steam and heat literally goes out the door.

So we go out, putty knives in hand, cleaning door thresholds, making sure the door is re-sealed against the building. The knives scrape the snow from the threshold, and from the underside of the door. It builds up against the door frame as well. If you’re really unfortunate, or in the right storm, hot air from the building is melting the snow in the way, and it re-freezes to rock hard ice.

We’ll gladly do the shoveling, plowing, and salting. Save us some time, though, and close the door behind you. What, did you grow up in a barn? Snow stuck in the threshold? Grab a knife from the dining hall if you have to, I won’t tell Aunt Des.

Snow Days

Categories: Midd Blogosphere

Luther Tenny (Facilities Snow Guru, and master of the Snow Plan) keeps much better track of snow storms than I. The weather station down at the track records liquid precipitation year round, thanks to a small heater melting snow in the rain guage. This has recorded .91″ so far in January, compared to 1.35″ to date last year. In December, 1.92″ of precip. fell, as compared to 1.5″ in 2009. The difference this winter seems to be frequency.

Luther reports 11 snow events so far this year, a snow event being one all of facilities needs to respond to. An average winter contains 18 snow events in total. He also states 19 of the last 20 days in January has seen some snow, and 24 of the 31 days in December.

I never got around to posting this, but here’s a great satellite picture of the nor’easter that hit us on January 12. I’ve lost the name of the site it came from, but I remember it’s from the National Weather Service. We’re in a break from snow now, as the bottom seems to be dropping out of the thermometer. Some of the coldest arctic air we’ve seen in 2-3 years is plunging south, so stay warm.

Snowy Scenic Sauntering on a Sunny (Almost) Solstice Sunday

Categories: Midd Blogosphere

I had hoped that by this time in December, I would be sharing new ski touring adventures.  While there is some cross country skiing to be enjoyed, the cover is a little too thin to get out of well-groomed fields and into the more uneven terrain of the woods.  That said, I have no objection to trail running in the snow, at least shallow snow, and on this gorgeous sunny day, it seemed a great day for a run on paved road, dirt road, and trail.

For this run, I am revisiting a segment of a run I first described two summers ago entitled “Secret Meadow” where I described an infrequently visited meadow up on the hillside above Upper Plains Road on the Middlebury/Salisbury border.  Today’s run started on the road, however, at the parking lot by the playground on Schoolhouse Hill Road in East Middlebury.  Heading east up the Middlebury Gap Rd. past the Waybury Inn brought me to what ended up as the hardest part of the run – the short steep road ascent of Sand Hill.  Shortly after topping out this challenge, I took the right turn on Upper Plains Rd., which was not surprisingly snow-covered.  Looking through the normally thick woods enveloping  the road, I spied a variety of trails which remained largely hidden in the undergrowth during the summer, and made a mental note of their location for future exploration.  After a little over a mile on Upper Plains Rd., there is an obvious trail heading to the left on the other side of a forest service gate.  A few yards up the trail, the main trail bore left, with a steeper, more narrow trail to the right.  Curiously, there was a sign directing ATV’s to this trail, but guess which way the tire tracks went?  Guess which way I went?

Wrong Way Tire Tracks

A short steep ascent brought me to the Secret Meadow itself, which looks quite different in the wintry landscape than it does during summer runs! While it was all blue sky overhead, haze and clouds to the west obscured the often spectacular Adirondack views from this hillside. Turning around, and gazing uphill to the east, I was impressed by rugged appearance the low rounded hills behind me took on when snow covered and devoid of foliage.

Westerly Views

Returning down the gentler route chosen (apparently inappropriately) by the previous ATV’er, and retracing my steps in descent brought me back to the start, for a slightly less than 5 mile run with a very sane 550 ft of climb and and descent. Have a great Christmas, and hope for more snow!

Altitude Profile

Magic (Salt)

Categories: Midd Blogosphere

We’ve had quite the snow week, even though it rapidly disappeared in the rain Sunday. I’ve written about how we remove snow in the past, it’s one of my favorite posts. And what I said certainly still holds true, that a job well done means that no one really noticed we did anything at all. Presto, the roads and sidewalks are clear. This year, we’ve made it a little easier for ourselves, and for the environment, with clearer and safer surfaces to boot.

The issue with snow and ice is always one of traction. Getting rid of most of the snow is relatively easy. Shovels, plows, snow blowers, brooms, even backpack blowers are all used, depending on conditions. The challenge in the winter is the last 1/4″ or so, the snow or ice remaining that doesn’t want to go anywhere. The problem is warmth, and the fact that the very first snow that falls on sidewalks or roads bonds to the surface, and can be very hard to scrape away and remove. This is what makes winter treacherous, and what makes walking and driving difficult.

In the past, Facilities Services has used sand, and a lot of it. Spread on top of this bonded snow/ice hard pack, the sand gives traction on top, making the walk or road a little less slippery. Most of the time. Sand comes with costs, though, some obvious, some not so much. Sand use in winter is linked to phosphorous loading in streams, sedimentation buildup in catch basins, retention ponds, and waterways, and even airborne pollution, as the cars and trucks driving across the sanded surface grind the particulates into finer particles and allow them to become airborne. But the worst part of sand? The carbon footprint, not only in spreading a heavy product, but repeated trips to refill, the continual scraping of the surface to try and remove the leftover hardpack repeated over days, and worst of all, the massive amount of work and fuel required in the spring to clean all the sand up. After all that work, there is still snow and ice left on the walk. The sand seems to disappear, moving off the hardpack to the edge, and the walks are slippery again.

The other solution to the ice problem is to get rid of it, frequently by melting it. In a bulk scale, this usually involves rock salt. Ever make homemade ice cream? Rock salt lower the freezing point of ice, so that it stays liquid at a colder temperature, allowing the milk to freeze. Applied to a road, the salt thaws the ice or snow hardpack, where it runs off as water, drying the road. This certainly has it’s problems too, not only in the carbon footprint to get salt across the country, but in effects both in water and soil of excessive salts. There are other ice melter products, from calcium chlorides to magnesium blends used on airport runways, but most bulk applications still rely on plain old salt.

Facilities wasn’t satisfied with sand, as anybody walking across our sidewalks in the past might attest to, but we weren’t sure about salt, not wanting to make an environmentally worse choice. (It’s neck and neck, actually, between sand and salt, if you actually take the time to weigh the pros and cons.) A couple of years ago we started using Ice Ban as a pretreatment. This liquid is the byproduct from food manufacturing (I believe our source is actually from beer), and sprayed on sidewalks and roads before a storm can prevent the dreaded bond from forming, allowing the snow to be completely removed. This is tricky, though, as conditions need to be perfect in order to apply, and this only seems to be about 2/3-3/4 of our snow events. Then we discovered magic.

Magic Salt is ordinary rock salt treated with ice ban, or an equiviant. This agricultural by-prodcut gets sprayed on the salt, turning it brown and giving it a somewhat funky smell. It makes the freezing point of water drop even lower, meaning less treated salt is needed to melt the equivalent amount of snow or ice. Some estimates claim 30-50% less. And much much less sand/salt mix, up to 3 times less. Less product=less carbon. And we’ve got cleaner sidewalks. This is our first year of trying Magic Salt, and so far we’re impressed. But don’t take my word for it, the proof is in the pictures.

Here’s a sidewalk treated conventionally with ordinary rock salt (not by the college). Yes, the sidewalk is clear, but note not only the chunks of excessive salt remaining, but the white residue of the salt on the walk. It’s very easy to over apply salt.

This is one of our walks, treated with Magic Salt. Very clear, but notice there is no excess salt on the surface, and no white buildup of salts on the sidewalk either.

One night this week it snowed on top of cleared sidewalks in the middle of the night, and night time temperatures were in the single digits. Temperatures this cold are below the effectiveness of straight salt, it just won’t melt the snow. The sidewalk above was treated with straight rock salt the day before, and you can see the bond that formed between the walk and the snow. There are footprints in the snow above. Compare it to the the picture below.

This sidewalk was treated with Magic Salt the day before, and, while it has received more foot traffic than the walk above, you can still see how there is no bond formed. Even walking on this sidewalk was more pleasent, and not as slippery as if the snow had bonded down. And with this type of surface we can…

Sweep the walk clear. A broom on one of our tractors came along and in no time at all discovered the bare surface again.

It’s Snowing, and it’s almost May

Categories: Midd Blogosphere

April 27th, and there is a couple of inches of snow on the ground. Enough so I’m wondering if the Montery School needs any landscaping help. It’s not the snow that’s disconcerting, it’s the 3-7 ” additional forecast for tonight. The temperatures yesterday were in the 60’s, and now it’s about 36.

Here’s a slideshow of some pictures of the snow. Click on them for a larger, colder, and slightly more depressing view.