15.3.2.5. Great Lakes-St. Lawrence Subregion
Scenario-based studies in the Great Lakes-St. Lawrence basin conducted over
the past 15 years (see Section 15.2.1) have indicated
consistently that a warmer climate would lead to reductions in water supply
and lake levels (Cohen, 1986; Croley, 1990; Hartmann, 1990; Mortsch and Quinn,
1996; Mortsch, 1998). Observed low-level events have been rare during the past
several decades, but when they have occurred (e.g., 1963-1965, 1988), conflicts
related to existing water diversions and competing stakeholders have led to
legal challenges and political stress (Changnon and Glantz, 1996).
In 1998-1999, dry and record warm weather combined to reduce ice extent
and lower water levels (Assel et al., 2000). In November 1998 and again
in spring 1999, cargo limits were placed on ships travelling through the Great
Lakes and the St. Lawrence Seaway when water levels fell by more than 25 cm.
Some commercial ships ran aground. Lower water levels significantly increased
the distance between docks and waters at some tourism facilities and marinas.
Recreational boaters had access to fewer waterways. In addition, hydroelectric
facilities are very dependent on water flows and have expressed concern about
maintaining production (Mittelstaedt, 1999). These observed impacts are similar
to the impact scenarios described earlier. The reduction in ice cover did provide
some offsetting benefits by reducing the need for icebreakers during the winter
and spring (Assel et al., 2000).
Water resources management, ecosystem and land management, and health concerns
are highlighted in the Great Lakes-St. Lawrence Basin Project (GLSLB) and
the Toronto-Niagara Region Study (TNR). The former is a binational exercise
that used analogs and model-based scenarios to assess impacts and adaptation
responses. Reduced lake levels continue to be projected, leading to potential
conflicts over water regulation and diversions, water quality, and rural water
use (Mortsch et al., 1998). The TNR exercise is in its initial stages.
Within the GLSLB region, the TNR represents a highly urbanized area that has
a significant impact on surrounding agricultural and forest landscapes. Urban
influences on land use, air quality, and human health will be a major focus.
In addition, concerns about vulnerabilities of the built environment (transportation
and energy infrastructure, etc.) have been identified as high-priority research
questions (Mills and Craig, 1999).
There also have been studies of alternative scenarios for lake-level management.
Decision support systems can facilitate this process (Chao et al., 1999).
15.3.2.6. North Atlantic Subregion
Severe winter storms combined with a loss of power can have devastating consequences,
even in a highly developed region such as Ontario-Quebec and the northeast United
States. In January 1998, a severe winter storm struck; instead of snow, some
areas accumulated more than 80 mm of freezing rain—double the amount of
precipitation experienced in any prior ice storm. The result was a catastrophe
that produced the largest estimated insured loss in the history of Canada. The
same storm ran across northern New York and parts of Vermont, New Hampshire,
and Maine in the United States (see Table 15-5).
The basic electric power infrastructure, with its lengthy transmission lines,
was severely damaged, stranding some residents and farmers without power for
as many as 4 weeks. Almost 5 million people were without power at some point
during the storm, and consideration was given to evacuation of Montreal. In
Canada, there were 28 deaths, and damages were US$2-3 billion (CDN$3-4 billion)
(Kovacs, 1998; Kerry et al., 1999). The same storm caused 17 deaths in
the United States, as well as damages exceeding US$1 billion in New York and
the New England states—one-third of which was from losses to electric utilities
and communications (DeGaetano, 2000). Combined Canadian and U.S. insured losses
stood in excess of US$1.2 billion as of October 1, 1998. Total Canadian insured
and uninsured economic losses were approximately US$4 billion (CDN$6.4 billion).
The ice storm produced more than 835,000 insurance claims from policyholders
in Canada and the United States. This was 20% more claims than were created
by Hurricane Andrew, the costliest natural disaster in the history of the United
States.
The event served as a grim learning laboratory for the insurance and disaster
recovery communities. It revealed the wide spectrum of insured and noninsured
losses that can materialize from a single natural catastrophe, including:
- Property losses (e.g., roof damages and destruction of perishable goods
as a result of loss of electric power)
- Business interruption losses (19% of the employed Canadian workforce was
unable to get to work)
- Health/life losses (including losses incurred during recovery operations)
- Additional living expense costs for people relocated to temporary housing
- A host of agricultural losses, ranging from livestock deaths, to interrupted
maple syrup production, to milk production
- Disruption and damage to recreation and tourism infrastructure
- Disaster recovery costs, including personnel and overtime expenses, provision
of backup electric generators and fuel, debris clearing, temporary shelter
for displaced citizens, and disaster assistance payments to victims.
Ice storms occur regularly in North America, although severe and prolonged
damage is rare. Several urban centers are vulnerable to major storms, including
Minneapolis, Winnipeg, Chicago, Detroit, Toronto, Buffalo, Montreal, Boston,
and even New York. Many communities are not prepared for an extreme winter storm,
particularly combined with the loss of electric power. In the 1998 storm, total
losses exceeded insured losses by a substantial margin. The event also raised
questions about the connection between such events, the El Niño phenomenon,
and global climate change.
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