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What's in a tonne?

It doesn't take much to make a tonne. I've often wondered what a tonne of greenhouse gas emissions looks like. It's easy to say that the average Edmontonian emits about 5.

It doesn't take much to make a tonne.

I've often wondered what a tonne of greenhouse gas emissions looks like. It's easy to say that the average Edmontonian emits about 5.47 tonnes of emissions a year, according to the City of Edmonton's office of the environment, but is that a lot? What does it do to the air?

Like a cloud of emissions, a tonne is a big, nebulous concept — I needed to make it real.

Ten minutes later at Canadian Tire, I had my reality — 85 five-litre gasoline jugs on the floor, covering an area the size of a small car. The 424 litres of gas that could fit in these jugs, if burned, would create a tonne of emissions, according to the U.S. Environmental Protection Agency (EPA). If I added four more layers, I'd have a year's worth of emissions for one person and a pile as high as my head.

A tonne of emissions is pretty big, but it can be caused by something as small as a light bulb. Understanding what goes into a tonne can help you come to grips with climate change.

It's a gas

I asked Andrew Weaver, the Canada Research Chair in climate modelling at the University of Victoria, what was in a tonne of greenhouse gas emissions.

Greenhouse gases trap heat radiated by the Earth, he says, warming it. There are lots of them, but the Kyoto Protocol singles out six that are closely associated with human activity — carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulphur hexafluoride.

CO2 is the biggest contributor to man-made global warming, Weaver says, responsible for about 3.5 times more warming than its nearest competitor, methane. "It's a quantity issue; there's just so much more of it." This is why nations usually convert the other gases into CO2 or carbon: one tonne of methane is equivalent to 21 tonnes of CO2, for example, while a tonne of CO2 equals about 0.27 tonnes of carbon.

A tonne of carbon will stick around for one to 1,000 years, Weaver says, and warm the Earth by an amount equal to the heat from 31 60-watt light bulbs. If you want to picture the effect of Canada's annual emissions (about 204 megatonnes of carbon), imagine adding about 6.3 billion bulbs to the sky, about 200 per Canadian.

It's half a hybrid

Researchers are working on carbon-capture techniques that can suck emissions out of the air, Weaver says, but they're years away from viability. "Right now, the only cost-effective way to remove a tonne of carbon [dioxide] is to not put it up in the first place." That means burning fewer fossil fuels through energy efficiency.

There are many ways to prevent a tonne of emissions, according to the Pembina Institute's onelesstonne.ca website, most of which pay for themselves. Replacing all the incandescent bulbs in a four-person home would prevent 1.5 tonnes, for example, and save you about $135 a year.

One good way to shed tonnes is through transportation. Vehicles account for about half of most Canadian's personal emissions, according to the federal One-Tonne Challenge guide, so you can reduce emissions by changing your car. A mid-sized car driven 200,000 kilometres emits about four tonnes, the guide says; a hybrid emits just two.

The hybrid emits less because it burns less gas, says Scott Wilson, who drives one regularly as an analyst with the Alberta Motor Association. "It's possible to get to the point where you're driving at four litres per 100 kilometres," he says, compared to about nine for an equivalent sized non-hybrid. "That's a significant difference."

My hybrid gets about 5.8 litres per 100 kilometres and, according to Google Maps, could get to Montreal and back on a tonne's worth of emissions (424 litres of gas). A typical Alberta car would burn twice as much gas on that trip, according to the 2007 Canadian Vehicle Survey, at twice the cost for twice the emissions.

You don't need to buy a hybrid to cut tonnes, Wilson notes. Proper braking and accelerating can shave 15 per cent off your mileage, he says, as can driving 90 instead of 110.

"Do I need to drive today?" Wilson asks. Taking a bus can cut your transportation emissions by up to 25 times, and a bike would all but eliminate them. Car-pooling five days a week will eliminate about a tonne's worth of emissions, according to the Pembina Institute, and save you about $269.

It's a year of solar

You can also get rid of a tonne by changing energy sources.

St. Albert's fire hall No. 3 is one example. The city spent $17,500 to put a kilowatt of solar panels on the hall in 2008, says city project manager Jon Cleland. Energy from the panels reduced the need to burn fossil fuels, keeping 2.5 tonnes of emissions out of the air. "That's not bad, considering the only power that's being supplied there is [enough] to run a kettle."

You can also switch to wind power through groups like Enmax and Bullfrog Power, as some St. Albert homes and businesses have done. I did so for about $140 a year, which has reduced my annual emissions by about six tonnes.

Wind power has big impact here in Alberta because our power is so carbon-heavy, according to Tim Weis of the Pembina Institute. "Coal is a really major problem in terms of greenhouse gases in Alberta," he says, and is the biggest emission source in the world. Since about 70 per cent of Alberta's electricity comes from coal, it doesn't take much to make a tonne of emissions — 18,000 60-watt bulbs burning for an hour would do it.

It's 26 trees

Trees are mostly carbon, and can remove tonnes of emissions through their growth. Planting about 26 tree seedlings and growing them for 10 years should trap about a tonne of emissions, according to the EPA.

St. Albert's Mission Hill is host to many such plantings, says city arborist Kevin Veenstra. "There's nothing like planting a tree to really get you in touch with the environment." Kids planted about 500 seedlings on the hill last Arbour Day, which will trap about 20 tonnes of emissions if they last a decade.

Unfortunately, not all of them have. A brief inspection by Veenstra reveals several that are dying because of bugs or drought, and one that's been run over by a vehicle.

That's one of the issues with using trees to offset emissions, say experts — permanence. "Preserving forest and planting trees is certainly an important thing we have to do to combat climate change," says Stewart Elgie, a professor of environmental law at the University of Ottawa, as deforestation accounts for about a quarter of all climate change. But if the trees die or get cut down, they cease to be an offset.

"The problem isn't the nature of the offset," Elgie says. "It's a failure of government."

Provided you have a really good regulatory framework, buying or planting trees or other offsets can make real emission reductions. Unfortunately, most frameworks aren't that good, which creates the risk of people buying bogus offsets.

It's one hour

Climate change is a huge problem, but breaking it down into tonnes helps make it manageable. Small actions, done by enough people, can chip away at that stack of 85 gas containers and make a tonne disappear.

Think about that when you shut off your lights tonight during Earth Hour: every 18,000 lights out in Alberta will mean one less tonne in the air.

Earth Hour

Earth Hour, an international event organized by the World Wildlife Fund, runs from 8:30 to 9:30 p.m. around the world on March 27. Residents are encouraged to turn off all non-essential lights during this time to raise awareness of climate change. For more, visit earthhourcanada.org.


Kevin Ma

About the Author: Kevin Ma

Kevin Ma joined the St. Albert Gazette in 2006. He writes about Sturgeon County, education, the environment, agriculture, science and aboriginal affairs. He also contributes features, photographs and video.
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