January 2011
Phone: 260-463-4901 • Fax 888-439-6528 • The Hometown Treasure
Page 30
SPOLTLIGHT ON NATURE — cont. from previous page
Where relatively warm water bodies are present,
for example due to water evaporation from lakes, lakeeffect snowfall becomes a concern downwind of the
warm lakes. Lake-effect snowfall can be locally heavy.
Thundersnow is possible within a cyclone’s comma
head and within lake effect precipitation bands. In
mountainous areas, heavy snow is possible where
upslope flow is maximized within windward sides of the
terrain at elevation, if the atmosphere is cold enough.
If the snow is on the ground, snow can be categorized
as powdery when fluffy, granular when it begins the
cycle of melting and refreezing, and eventually ice once
it packs down, after multiple melting and refreezing
cycles, into a dense mass called snow pack. When
powdery, snow moves with the wind from the location
where it originally landed, forming deposits called
snowdrifts which may have a depths of several inches
up to multiple feet.
After attaching to hillsides, blown snow can evolve
into a snow slab, which is an avalanche hazard on steep
slopes. The existence of a snowpack keeps temperatures
colder than they would be otherwise, as the whiteness
of the snow reflects most sunlight, and the absorbed
heat goes into melting the snow rather than increasing
its temperature. The water equivalent of snowfall is
measured to monitor how much liquid is available to
flood rivers from melted water which will occur during
the following spring.
Snow cover can protect crops from extreme cold.
If snowfall stays on the ground for a series of years
uninterrupted, the snowpack develops into a mass of
ice called glacier. Fresh snow absorbs sound, lowering
ambient noise over a landscape because the trapped
air between snowflakes attenuates vibration. These
acoustic qualities quickly minimize and reverse, once a
layer of freezing rain falls on top of snow cover. Walking
across snowfall produces a squeaking sound at low
temperatures. The energy balance of the snowpack
itself is dictated by several heat exchange processes.
The snowpack absorbs solar shortwave radiation that is
partially blocked by cloud cover and reflected by snow
surface. A long-wave heat exchange takes place between
the snowpack and its surrounding environment that
includes overlying air mass, tree cover and clouds.
Heat exchange takes place by convection between
the snowpack and the overlaying air mass, and it is
governed by the temperature gradient and wind speed.
Moisture exchange between the snowpack and the
overlying air mass is accompanied with latent heat
transfer that is influenced by vapor pressure gradient
and air wind. Rain on snow can add significant amounts
of thermal energy to the snowpack. A generally
insignificant heat exchange takes place by conduction
between the snowpack and the ground. The small
temperature change from before to after a snowfall
is a result of the heat transfer between the snowpack
and the air.
The term snow storm can describe a heavy snowfall.
A blizzard involves snow and wind, obscuring visibility.
Snow shower is a term for an intermittent snowfall, while
flurry is used for very light, brief snowfalls. Snow can
fall more than a inch at a time during a single storm in
flat areas, and meters at a time in rugged terrain, such
as mountains. When snow falls in significant quantities,
travel by foot, car, airplane and other means becomes
highly restricted, but other methods of mobility become
possible. Oh what fun it can be to use snowmobiles,
snowshoes and skis!
When heavy snow occurs early in the fall, significant
damage can occur to trees and buildings because of
the weight it carries.
Substantial snowfall can disrupt public facilities
and services, slowing human activity even in regions
that are accustomed to such weather. Air and ground
transport may be greatly inhibited or shut down entirely.
Basic utilities such as electricity, telephone lines, and
gas supply can also fail. In addition, snow can make
roads much harder to travel and vehicles attempting
to use them can easily become stuck.
The combined effects can lead to a “snow day”
on which gatherings such as school, work, or church
are officially canceled. In areas that normally have
very little or no snow, a snow day may occur when
there is only light accumulation or even the threat of
snowfall, since those areas are unprepared to handle
any amount of snow.
Snow can be fun at the same time, so get out as you
are able to and enjoy all the fun benefits of the snow!
“A gentle, caring approach to foot & ankle care.”
Dr. C. Cody Cull, D.P.M.
Foot & Ankle Specialist
260-577-4082 for Appt.
PRIMARY CARE
PODIATRY
Including treatment of ingrown
nails, heel pain. Diabetic, ulcer and
wound care. Corns, callus, and nail
debridement. Prescription orthotics.
Diabetic shoes & inserts.
Conservative Treatments Used First
Surgical Correction If Necessary
House calls available
— Medicare and Most Insurance Accepted —