The more greenhouse gases that are in the atmosphere, the more heat gets trapped, and as the temperature rises, the result is climate change. Scientists predict that as the climate changes, the spread of diseases will increase, agricultural production will decline, and extreme weather such as floods and tornadoes will become common.
Carbon dioxide is one of the most problematic greenhouse gases as far as climate change goes. The amount of carbon in the atmosphere increases as fossil fuels are burned, so the use of coal, oil, and gas for heat and transportation means that carbon dioxide is released into the atmosphere in excessive amounts, at very fast rates, and the Earth does not have the capacity to absorb it. The effects on the climate are now becoming obvious. The northern hemisphere is warmer than it has been at any point in the past 1000 years, natural disasters including hurricanes and floods are increasing, and changes in lake and river levels mean that food supplies are threatened.
In order to stall or turn back global warming, we need to dramatically reduce the amount of fossil fuels we emit, and ensure that carbon sinks are protected. Unfortunately, by developing the Alberta tar sands, oil companies are doing precisely the opposite.
Tar sands development is the single largest contributor to the increase in climate change in Canada, as it accounts for 40 million tonnes of CO2 emissions per year, and means that thousands of hectares of ancient Boreal Forest are clearcut and destroyed. These numbers are increasing: by 2011 it is expected that the tar sands will emit 80 million tonnes of CO2 emissions. Please note that these numbers only take into account the production of oil from the tar sands. Once tar sands oil is burned as fuel, it does create further “end-use” emissions.
Canada made an international commitment to meeting GHG emissions reduction targets outlined in the Kyoto Protocol – the goal was to reduce emissions to six per cent below 1990 levels by 2010. Unfortunately, Canada has been unsuccessful at achieving even this small number so far. As of 2004 emissions levels had significantly increased. In order to meet the targets, emissions must go down by 280 million tonnes per year. If the tar sands continue to operate as predicted, there is no hope of accomplishing this.
Why do the tar sands cause so many emissions?
The oil that is being sought from the tar sands is literally stuck in tar and it is very difficult to separate them. Huge industrial machines are needed to dig the mineable tar sands out of the earth, and these burn a lot of fuel. As two tonnes of tar sands must be moved in order to create a single barrel of oil, this means that 35 kg of CO2 equivalent is emitted, making oil from the tar sands the most energy intensive type of oil available.
If the tar sands are located deeper than 100 metres from the Earth’s surface, and cannot be mined, they are extracted by a process called steam-assisted gravity drainage (SAGD), which creates even more emissions than mining: 55 kg of CO2 per single barrel of oil. In SAGD operations, steam is injected into the tar sands to make it flow, and then it is pumped to the surface. Heating the water for the steam greatly increases the amount of fossil fuels that are burned.
As mentioned above, bitumen is the heaviest and worst quality oil available. It has to be processed and refined heavily to be turned into synthetic crude oil, which involves further use of steam and energy.