| Great
Snow! It's the single most important ingredient at a ski/snowboard
resort and the #1 priority at Nub's Nob. Without great snow,
nothing else matters. While our natural snowfall average hovers
around the 130” per year mark, artificial snowmaking
is still the lifeblood of the area. Our experience, commitment
and dedication to producing the finest man made snow surfaces
is the cornerstone of our mission.
The Basics of Snow
First, a fundamental: artificial machine-made snow is REAL
snow. There's nothing artificial about it. Snow crystals —
however they're produced — are simply small crystals
of frozen water. In nature, evaporation of water from the
ground, lakes, rivers and the oceans creates moisture in the
atmosphere. Under the proper conditions, this moisture condenses
- and when the weight of the moisture exceeds the capacity
of the air to keep it aloft, it falls to the ground. If the
air above the ground is cold enough, it falls as snow. Often
the crystals pick up more moisture as they fall, resulting
in the myriad shapes for which snow crystals are famous.
The Basics of Snowmaking
Machine snow shortcuts the process. There's no evaporation
phase; the water is pumped as a liquid from our pond which
is replenished by six wells dedicated to snowmaking. This
high pressure water (350 to 400 PSI) is forced into a ring
of specialized nozzles mounted on the front of a large volume
fan. This ring of nozzles breaks the water into very small
particles making them easier to freeze. In the center of this
ring we inject a smaller stream containing a mixture of highly
pressurized air and water. This compressed air/water mixture
freezes instantly as the compressed air expands after it leaves
the nozzle and “nucleates” or seeds the water
coming from the ring. We are so particular about the way this
process happens we invented and patented our own gun after
we got it just right. We use only Nub's Nob snow guns built
right here in our shop.
From here, the process is similar to Mother Nature's: the
small droplets of water mix together, freeze and fall to the
ground as snow crystals. The only difference is that the water
doesn't have as much time to freeze before it hits the ground.
It takes a massive snowmaking system managed by an experienced
crew to make the great snow you are used to at Nub’s.
Physics lesson: What makes water freeze?
In terms of pure physics, there is no such thing as cold.
There is only heat - more heat, and less. Heat always tries
to reach equilibrium - so it will flow from an area of more
heat ("warmer") to less heat ("colder").
When liquid water freezes, the water gives off heat until
it reaches the point at which it crystallizes. We generally
assume this will happen at precisely 32 degrees Fahrenheit
- which it in fact does only under highly controlled circumstances.
When we look out the window at our thermometer, we see what
meteorologists refer to as dry bulb temperature. It may give
us guidance on how to dress, but when it comes to the physics
of freezing water droplets, it doesn't tell the whole story.
The amount of moisture in the air - relative humidity - also
impacts how quickly a water droplet will give off heat and
become "cold".
The way the human body is affected by heat and humidity gives
some insight. On a summer day with an 80 degree temperature
and a 95 percent relative humidity, we feel hot. That's because
our bodies are cooled by sweating - giving off warm moisture
into the atmosphere. On a humid day, the air won't absorb
as much moisture, so our bodies simply can't lose heat as
fast as we can on a 90 degree day with 20 percent relative
humidity. That's why we can feel cooler on a "warmer"
day. When people say "it's not the heat, it's the humidity"
- they're not fooling.
The speed with which a droplet of water radiates heat into
the atmosphere and becomes snow is affected by relative humidity
in exactly the same way.
As a result, modern snowmakers have less interest in the
dry bulb temperature than the wet bulb temperature, which
is a mathematical function of dry bulb temperature and relative
humidity. When the atmosphere is saturated and cannot hold
anymore moisture, the dry bulb and wet bulb temperatures are
exactly the same. This is also known as the dew point. But
when humidity is extremely low, the wet bulb temperature may
be subfreezing - less than 32 degrees Fahrenheit - when the
dry bulb temperature is as high as 40 degrees. This makes
it occasionally possible to make snow at temperatures well
above "freezing," and can prevent us from making
snow on some nights when the temperature is below freezing
but the humidity is high.
It takes a lot of water to make snow.
Our wells can pump over 5000 gallons of water per minute into
our supply pond. Five high pressure pumps then feed over 23
miles of underground piping, from 14” diameter main
lines to 4” return lines, to all of our 46 slopes we
make snow on. This water system is larger than most communities
in Northern Michigan!
It takes a lot of snow guns to make snow.
250 of our patented Nub’s Nob snow guns are used to
cover the entire area. Each of these guns was built right
here at Nub’s and can turn over 50 gallons of water
per minute into snow at temperatures below 29 degrees and
over 100 gallons of water per minute in snow at temperatures
below 17 degrees. We like it cold!
It takes a lot of electricity to make snow.
All of the snowmaking equipment, from supply wells and high
pressure pumps to the snow guns themselves, are powered by
480 volt, 3 phase electrical power. At full capacity we are
using over 5200 horsepower of electric motors!
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