Geoscience Reference
In-Depth Information
Motel business can boom during major storms.
Surprisingly, garage stations record heavier business,
too, because people unable to reach work can still
manage to travel to the local service station to
complete delayed vehicle maintenance. For most
industries, a major storm means lost production.
Contingencies must be made by certain industries -
such as steelworks - to begin shutting down blast
furnaces before a storm affects the incoming shift of
workers. Unless production is made up, industry can
lose profits and contracts, workers can lose pay and
governments, income-tax revenue. Worker and student
absenteeism can overload domestic power demand, as
these people are at home during the day utilizing
heating and appliances not normally used at that time.
Severe, rapidly developing, or unpredicted snowstorms
may even prevent the workers required for snow
removal from reaching equipment depots.
Annually, many cities in North America budget
millions of dollars to remove snow from city streets.
Most cities have programs of sanding and salting roads
and expressways to keep the snow from being
compacted by traffic and turning into ice. For the cities
surrounding Lake Ontario, the volume of salt used on
roads is so large that increased salinity now threatens
freshwater life. Snow-removal programs necessitate a
bureaucracy that can plan effective removal of snow at
any time of day or night during the winter months.
Inefficiency in this aspect has severe economic
repercussions on industry and retail trading.
All of these disruptions depend upon the perception
of the storm. Cities experiencing large annual snowfalls
are generally more prepared to deal with them as a
hazard. Snowfalls under 10 cm - considered minor in
the north-east of the United States - will paralyze
southern states. However, an awareness of snowstorms
can be counterproductive. In the western United States
- where on a personal level snowfall is considered an
everyday element of winter life - large snowfalls can
cripple many major cities because they do not prepare
for these higher magnitude events. In the eastern states,
large storms are expected, but continuous small falls are
not. Here, snow clearing operations and responses are
geared to dealing with larger storms.
The variation in perception and response to the
snow hazard is best illustrated around the Great Lakes.
Because of their heat capacity, the Great Lakes remain
unfrozen long into the winter. Cool air blowing over
these bodies of relatively warm water can cause them
to reach their saturation point and lead to rapid accu-
mulation of snow downwind. As the prevailing winds
are westerly in the southern lakes, and northerly
around Lake Michigan and Lake Superior, snowbelts
develop on the eastern or southern sides of the Lakes.
In these snowbelts, average annual snowfalls can
exceed 3 m - double the regional average. Often this
snow falls during a few events, each lasting several
days. Cities such as Buffalo on the eastern side of Lake
Erie are prepared for the clearing of this type of
snowfall, on top of which may be superimposed major
mid-latitude storms. Cities such as Hamilton at the
western end of Lake Ontario have to cope only with
the irregular occurrence of mid-latitude storms. Each
city has built up a different response to snow as a
hazard, and each city allocates different sums of money
for snow-removal operations. Buffalo removes its snow
from roads and dumps it into Lake Erie; if it did not,
snow would soon overwhelm roadsides. Hamilton uses
sanding and salting operations to melt smaller amounts
of snow, and only resorts to snow removal for the larger
storms. These two cities, within 60 km of each other,
thus have very different responses to snow as a hazard.
However, these average winter conditions are not
guaranteed. Too many mid-latitude cells - even of
low intensity - tracking across the Great Lakes will
diminish the duration of westerly winds and increase
the duration of easterly winds. Hamilton then becomes
part of a localized snowbelt at the western end of Lake
Ontario, while Buffalo receives little snowfall. Buffalo
may end the winter with millions of unspent dollars
in its snow-removal budget, while Hamilton has to
request provincial government assistance, or increase
tax rates to cope with the changed conditions of one
winter's snowfall.
The winter of 1976-1977 was a dramatic exception
for Buffalo. Abnormally cold temperatures set records
throughout the north-east. Buffalo's well-planned snow
removal budget was decimated by a succession of
blizzards. On 28 January, one of the worst blizzards to
hit an American city swept off Lake Erie. The storm
raged for five days and occurred so suddenly that
17 000 people were trapped at work. Nine deaths
occurred on expressways cutting through the city,
when cars became stalled and people were unable to
walk to nearby houses before freezing to death. Over
3.5 m of snow fell. Winds formed drifts 6-9 m high.
For the first time in United States history, the federal
government proclaimed a disaster area because of a
