The following is an essay I wrote for Biology 150 at UVic in my first year in 1995. I only recently rediscovered this essay when I was going through some old digital files on a very old Atari ST computer that I grew up using. I’m not sure if it is a draft or the final thing I handed in. I’ve edited it a bit… I have no idea what mark I got on it. 🙂
Unfortunately I don’t have the image files that would have gone along with the essay as they were likely gathered from print sources, but I’ve tried to find online representations of the sources that I have listed.
It is incredible that in the 19 years since I wrote this paper, very little has changed in terms of global action on climate change though the world did take action on CFCs and the Ozone layer. That action is the same type of action we still must take on CO2.
Chris Alemany November 1995 95-02646
The effects of greenhouse gases on the biosphere of Canada
Global warming is a global problem. It affects every ecosystem, every species and every organism on this planet. Unfortunately the blame is ours. Since the start of modern industry concentrations of greenhouse gases in the atmosphere have risen dramatically (CO2″25%”, CH4″50%”(CDIAC 1991).
These greenhouse gases rise into our atmosphere and trap heat which would normally escape into space. As a result climates, weather patterns and ecosystems are changing all around the world. This essay will concentrate on the effects of greenhouse gases and global warming. It will reveal what the consequences of expelling such vast quantities of these gases have been in the past and will be in the future. Although the main focus is on the effects on Canada the global nature of this problem means that sources from all around the world must be considered and discussed at least in part.
One of the biggest reasons for the increase of carbon dioxide in the atmosphere is the explosion of the population of humans on the earth in the past century. As one can see from the pie charts below the human population doubled from 1950 to 1990 and is expected to nearly double again in the next thirty to forty years. This population increase means that there will be more industry, more cars, more burning of fossil fuel and more carbon dioxide in the atmosphere. Obviously if ways are not found now to prevent the release of greenhouse gases the problem will only grow with the number of people.
Figure 2: [Inserting from Wikipedia]
This is a map of the “Neartic Biogeographical realm” and its provinces which often stretch across Canada and the continental United States including Alaska. The provinces which lie within the territory of Canada are : (Francis, 1982) Sitkan (1) Alaskan Tundra (5) Arctic Archipelago (9) Yukon Taiga (2) Canadian Tundra (6) Artic Desert/Icecap (10) Canadian Taiga (3) Rocky Mountains (7) Great Lakes (11) Sierra-Cascade (4) Grasslands (8) Eastern Forest (12)
Canada, along with the rest of the world has a major problem when it comes to CO2 and other greenhouse gas emissions. Canada has already felt some of the consequences of those emissions in the form of unusually warm and violent weather. Many scientists believe that the horrible floods which wiped out parts of southern Saskatchewan and Manitoba along with most of the farm land down the Mississippi were caused by an overall increase in the global temperature of nearly half a degree Celsius (qtd. in Fantechi, Ghazi 215).
These floods were responsible for the destruction of thousands of hectares of farmland in the prairies or “grasslands”(Francis 1982). This is a major biogeographical province (see Figure 2) that extends from the foothills of the Rocky Mountains to the shores of the Mississippi and travels all the way to the gulf of Mexico. This is the first of many examples of the chaos which can and will happen if global warming continues unchecked. There are many more predictions of what might happen if global warming goes on unchecked.
It is revealed that an increase in mean temperature over the Canadian prairies could lead to drought. Canada contains only “1.44% of the world’s agricultural land” (Gregorich et al. 1991) and to lose even a fraction of that would be disastrous to the economy and ecology of Canada.
If the drought scenario did occur however, soil in the central and northern parts of the prairies could be freed from the grips of permafrost. One estimate indicates that if global trends continued “3.1 million hectares of organic soils”(Arthur, 1987) would be freed from permafrost. This is a major change in the ecosystem of the area. Instead of a barren land with sparse vegetation it might begin to show signs of supporting higher forms of plant and animal life. Changes like those could seriously disrupt current ecosystems.
Global warming can not only affect prairie ecosystems but also affect ecosystems along coastal shores. The rise in temperatures means that reduced annual accumulations of ice and snow on the poles and glaciers of the world are possible.
That means that less water is evaporating into the atmosphere from the sea than is melting or running off from land. As a result global sea levels could rise: by “2040: + 27 cm; 2080: + 46 cm; 2120: + 69 cm”(Fantehi, Gazhi 1986) Even though these numbers seem small the effect it could have on the present seashores could be devastating. All current intertidal zones would be fully immersed in water and the organisms which depend on the tidal action of the area would perish. Such organims include clams and gooeyducks which need sand to burrow through and tidal action to provide them with nutrients.If the sea level were to rise present day sandy beaches could be permanently flooded and the rocky shores which dominate much of coast of Canada could become intertidal.
Consequently the clams would have no place to burrow and receive nutrients and therefore would be required to emigrate to other locations. This could leave a large gap in the marine food web of the region and lead to reduced biological productivity in the area.
Not only do greenhouse gases trap heat some, such as chlorofluorocarbons (CFC’s), destroy the ozone layer that protects the earth from dangerous ultraviolet light. It has been found that an increase in harmful ultraviolet light (UV-B) have had “an adverse effect on phytoplankton populations”(Macdonald et al. 1992) in the Antartic Ocean, the area with the most prominent lose of ozone. Phytoplankton is a major component in the marine foodwebs of the world. Canada’s west coast has a large population of phytoplankton and has many species which depend on its presence. Therefore, if it is true that an “ozone hole” has developped “over populated regions of the Northern hemisphere”(Macdonald et al. 1992) then those populations of phytoplankton may be in danger.
As one can clearly see the effects of greenhouse gases on the biosphere of Canada and the world are both numerous and dangerous. Global warming and depletion of the ozone layer contribute to such things as thawing of the polar ice caps and extirpation of species from an area. These huge changes of environment lead to the break down of ecosystems and a change in the basic biogeographical boundries which have existed for milions of years.