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Human Settlements, Energy, and Industry



Impacts of climate change in and around the Great Lakes will be experienced by this area with the greatest population density in Canada. This area is around the west end of Ontario from Niagara Falls to Oshawa. It is called the Golden Horseshoe. This area is the economic engine for Ontario with 66% of the Ontario GDP. It is predicted that by 2031 the Golden Horseshoe will add 4 million people.

The 3 maps below document the historic growth of the area and the projected growth in what is now called the Greater Golden Horseshoe – urbanized areas with dense population in 1967, 1992, 2004.











Source: Places to Grow: Better Choices, Brighter Future. Ontario Government – A Discussion

Paper, Summer of 2004

This area grew from a population of 5.4 million in 1981 to 7.8 million in 2001.
1. How many more million people? If 80 percentage of this growth occurred in the Greater Toronto Area (GTA) and Hamilton. How many people came here? Why?

Future Growth

Based on past and current growth trends, the future population of the Greater Golden Horseshoe is expected to grow by almost 4 million, bringing the region’s population to over 11 million by 2031. The map below represents the plan for meeting this growth in population.

Check the legend to understand the color code of the map features.
1. What percent increase is this over the next 25 years?
2. Approximately 75% of this growth is projected to occur in the GTA and Hamilton with most of the remaining growth expected to occur in the larger urban centers in the outer ring. How many more people will live in this area in 2031?
3. Since Canadians have an ecological footprint of 8 hectares of land per person that they depend on to meet their present lifestyle needs, what would be the ecological footprint for the population projected for this area in 2031?

ACTIVITY 3 Research
1. What would be 3 of the policies that Ontario could develop to ensure that the most environmentally friendly or sustainable designs were implemented for the growth projected for this area?
2. What housing design ideas would allow increased density with the most energy and space efficiency while having a friendly and green neighborhood?
3. Check Ontario government web sites for the conservation culture message the government is trying to convey.

Climate change can lead to increased heat stress and related air quality degradation in urban centres, such as Toronto. Increased frequency and severity of heat waves may lead to an increase in illness and death, particularly among elderly and frail people. These effects tend to be greatest when high heat levels occur early in the summer. Acclimatization may be slower than the rate of projected temperature change.

Respiratory diseases may also be exacerbated by warming-induced increases in the frequency of smog (ground-level ozone) events. See also Ground level Ozone (O3), Smog

1. Find the data that links asthma,smog, and hospital admissions for Ontario.
2. What causes smog ? Check the role of UV with ground level ozone and other air pollutants.

Industry and Shipping

Observations from 1846 to 1995 show both the length of ice cover season and the area of the ice cover have decreased in the Great Lakes Region. During this time the temperature also increased 1.2 C degrees per century. Ice Break up is now an average of 6.5 days earlier and freeze up 5.8 days later. In the last 150 years the lakes and rivers in Ontario have gained almost 2 weeks more of open water. See Albedo effect, Lake Snow effect.

Ports and commercial shipping schedules have changed. The Hudson’s Bay ice cover has decreased one-third since 1971. Shipping grain through Churchill as a port leading to the prairies and to the USA is cheaper than the ports on the St.Lawrence Seaway. Since 2002 one-third of all grains shipped have come through Churchill in spite of the fact that the port at Thunder Bay has an ice-free season that is twice as long. The change from Great Lakes ports to Churchill saved $10 million U.S. savings in 2002.

The good news is that Canada has developed better ice-mapping systems and better ice detection for safer navigation. We are changing our behavior due to reduced ice cover.

Both commercial shipping and recreation, such as ice fishing, are changing to meet the changing climate.

Source: International Joint Commission (IJC) Climate Change and Water Quality in the Great Lakes Region. May2003 www.ijc.org

1. What year was the Seaway opened?
2. What is the current total tonnage shipped in one season?
3. What does this table say about the costs of future Seaway activity?