Ontario-Great Lakes Region



Ontario in Context

Global impacts and concerns include Ontario

Human-induced climate change is causing dangerous interference with the natural global climate system. Human-caused climate changes have the potential to trigger extreme weather events. In this sense, humans are pulling the trigger on our planet!

Here is a key example of global climate change that affects Ontario.

1. Greater increases in temperature in global north cause more rapid melting of the Greenland/Arctic ice sheet. This affects ice cover in Hudson Bay and changes the North Atlantic thermohaline* that affects ocean circulation. Changes in the Atlantic gulf stream are a weather system factor for Ontario. The projections for climate change show that the greatest warming will be in the Arctic. More rapid melting is already being seen there. The figure below shows the shrinkage in area recorded by satellite for the same site over 24 years. The area of ice cap lost is shown within the dotted line. Note that the ice cap is also becoming thinner. The thinning of our Arctic ice has been measured for the last few decades by submarine runs. Peter Calamai , The Star (Science), August 11, 2004

Arctic Ice Cap Changes 1979-2003


Source: NASA http://www.gsfc.nasa.gov/topstory/2003/1023esuice.html

1. Compare the area covered by ice and estimate the percentage lost in the last years.
2. List the differences in density of ice, freshwater, and marine or saltwater.
3. a) What is the difference in reflectivity or albedo between ice or snow and ocean surfaces?
b) How will this difference in albedo affect the rate of melting the ice/snow cap?

The deep ocean boundary, the thermohaline, where circulating surface and deepwater temperatures meet is affected by the differences in density of freshwater vs. salt water. As the Arctic ice sheet melts the colder and less dense freshwater flows further south. Riding over the warmer, denser salt water flowing to the northern latitudes, the cold melt waters force the warm Gulf Stream water further south than its normal site to cool, sink, and recirculate. Climate patterns are changed by the different location of the warm surface water sinking. See Section 5.2.2b Ontario Ecosystems.

Ontario as Part of North America

Climate change is the long-term trend or overview of differences in historic climate.

Weather is what we experience in the short term, hourly or daily. Weather delivers the climate.

Notice on the weather map below that there is a lot of activity. For example, check the weather fronts over Ontario. This is because, in Ontario, the daily weather we experience is the result of 2 pairs of major systems vying for dominance. Four systems act as 2 pairs of contestants:

  • Polar cold dry vs. Tropical warm, moist
  • Atlantic cold wet vs. Pacific warm
  • Pacific vs. Atlantic struggle for dominance although westerly winds prevail.
  • Polar vs. Tropical air masses meet to deliver weather from north to south. The battle moves west to east due to the prevailing winds created as our planet turns.

Through a system of highs and lows of atmosphere pressure, fronts are formed where battles between the systems rage over Ontario 24 hours a day. The Ontario Meteorological Service tracks the fronts and tries to predict the weather as these systems fight to deliver our local weather. Prediction of even tomorrow’s weather winners is further complicated

  • by the effects of our large bodies of water, the Great Lakes and Hudson Bay
  • by elevations of land such as the Niagara Escarpment
  • the heat island effects of large cities.

A map of a one day weather report. Note the weather in action over Ontario.


Source: Environment Canada. www.weatheroffice.ec.gc.ca

1. What are the boundaries of Ontario with reference to:
a. the northern boundaries of the western Canadian provinces (60oN)?
b. the American states on the international boundary of the Great Lakes? c)in Ontario ?

2. Clip the weather maps for North America for two weeks. Study the Ontario weather forecasts for highs meeting lows over these two weeks. Climate studies use a minimum of 20 years as well as hundreds and even thousands of years of data as a base line to predict future climate.
3. Based on understanding these conditions, forecast the local weather for the next three days and then check your accuracy after the three days have passed.

Weather models may predict trends but the short-term or daily forecasts require human interpretation of situations causing daily local weather. Predictions of weather conditions cannot be exact for any specific location. Inaccuracies emerge when applying information from a continental scale to a smaller Ontario scale for the specific location. See scientific uncertainty*

The temperature graph below helps put Ontario into context for the global picture as region of Canada. Departures from the average mean are used as a method of documenting change.

The dark wavy line smooths out the average for all departures plotted.

Departures from the average mean temperature in oC 1990-1999 for southern Canada

(south of 60oN) based on 1961 -1990 temperatures.


Source: Zhang et al., Environment Canada, 2000

1. What is the range of degrees being documented in this study?
2. Examine the graph to understand why the dark line can represent the mean.
3. What is the overall trend from 1900 to 2000? Research: find and plot Ontario only data for this period.

This graph is important because a pattern of departures from a mean indicates change in climate. The greater the change in climate, the greater the instability and the unpredictability of climate, the greater the vulnerability to the impacts of climate change. Both natural and human or built environments are vulnerable to these impacts.

Human responses to these impacts can be to adapt to these environmental impacts and to reduce emissions to reduce the impacts. Some reports state that the key environmental impacts will be changes in temperature, precipitation, and water availability, and disease vectors.

The IPPC lists 5 major global concerns of climate change with respect to impacts, adaptation and vulnerability:

  • unique and threatened systems
  • total impacts
  • distribution of impacts
  • extreme weather event
  • large-scale single events

Note that climate change increases the changes, both in frequency and range, away from normal climate. More highs and lows differing from the mean increase the vulnerability to damage from the extremes and changes in climate patterns everywhere on the planet, including Ontario.

According to BBC News Online series Autumn 2004, humanity faces potential crises in 6 areas:food, water, energy, climate change, biodiversity and pollution. As the rest of this document shows -all of these will affected by climate change!

No matter which list is used, all of these concerns must be considered for Ontario’s future.

It’s a matter of scale (See Section 2.3, Climate Models)

Global research and predictions for climate change can be applied to Ontario but with less scientific certainty.The smaller the area used with global data for global modeling to develop scenarios for future conditions, the greater the level of difficulty for accuracy in predictions. This applies to the change in scale between a large area of the globe and a smaller area such as Ontario.

Global projections and scenarios for environmental impacts applied to Ontario thus have built-in loss of accuracy or become more unpredictable. Regional data,fjor example, for an area like Ontario, is more predicable at the regional scale. Hence provincial studies need to check the global data and then look for the same trends in Ontario, based on Ontario data.

Climate change has both beneficial and harmful effects which means good news /bad news for Ontario or, stated differently, both opportunities and challenges. The global predictions for climate change continue to apply.

Ontario predictions will be local variations of the global predictions. The size and number of maximums and minimums different from the average for any measurements will be increased, for example, highs and lows of temperature, precipitation, and water levels.

There are both challenges and opportunities in our future because of increased temperature and decreased water availability. Climate change will alter the timing or average start and finish dates of normal seasonal events such as ice cover, spring flowers. Changes in the length of any season, such as the number of frost-free days or the number of low stream flow days, will be also be seen as the trends,already observed, continue. Use the species at risk (SAR) map below to answer questions on Canada in general and Ontario in particular.


Part A
1. Canada has the second largest land mass on the globe – 9, 970,610 square kilometers.Ontario has 1,076,395 square kilometers.
2. What percentage of Canada’s land mass is Ontario?Ontario has 158,654 square kilometers of fresh water. What percentage of Ontario’s area is water surface?
3. What percentage of Canada’s population lives in Ontario? What percentage of the GDP is from Ontario?
Part B
1. Find the boundaries for Ontario. Note that 60oN is the latitude of the prairie provinces northern limit.
2. What is the total of threatened/endangered terrestrial species for Ontario? marine? freshwater?
3. What is the combined total of all threatened species in Ontario for 2001?

The map below indicates the 3 ecozones of Ontario with major highways and cities.

Source: Environmental Commissioners Office, About Ontario, 2004. www.eco.on.ca

1. Check an atlas and determine the latitude and longitude of
a) Ontario’s boundaries
b) Mixed Wood Ecozone
c) Algonquin Park.

Northern Ontario human populations and ecozones will experience greater impacts of climate change.

Changes in water levels and permafrost area affect all natural and built ecosystems. These changes will also have an impact, although indirect, on southern Ontario, for example loss of ice cover in Hudson Bay influences shipping volume and daily weather in southern Ontario.

The tiny land mass of Southern Ontario makes accurate predictions even more difficult on an even smaller scale. Global scale averages do not show local variations such as those due to local elevation, for example the Niagara Escarpment and large bodies of water, the Great Lakes.

The International Joint Commission was formed to deal with all matters relating to the sharing of the Great Lakes. The international boundary runs through the lakes. Check out the boundary lines on other Ontario maps.

1. Use a map of Ontario and calculate the percentage of Ontario covered by this watershed.
2. Assume that all waters in the yellow area flow into the Great Lakes. Draw a line on your Ontario map to represent a general boundary line for waters to flow north to drain into Hudson’s Bay.
3. Large landscape features influence local changes in climate . Draw a line to show where Southern Ontario begins. Draw lines to show the Niagara Escarpment and the Oak Ridges Moraine. See the previous maps.
4. Draw a line on your map to show the Golden Horseshoe. It was named for the dense population producing the greatest percent of GDP for Ontario. What predictions are being made for population growth here?
5. Locate the largest city in Canada, Toronto, on this map. What is the population? Energy used? Fossil fuels burned? Ecological Footprint? What are some of the new policies being recommended by this city government?




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