Science·What on Earth?

How to track your carbon footprint

In this week's issue of our environment newsletter, we look at the pros and cons of nuclear power and what you can do to make better sustainable living choices.

Also: The pros and cons of nuclear power

(Sködt McNalty/CBC)

Hello, Earthlings! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This week:

  • You want to reduce your carbon footprint. How do you know what works?
  • Nuclear power: The pros and cons
  • Who uses the most energy in the world?
  • Mailbag: How you're living more sustainably

Clearing the air: How do you actually measure your carbon footprint?

(Patricia de Melo Moreira/AFP)

We've received a fair number of emails at What on Earth? from environmentally conscious consumers who want to do good, but just don't know how.

Finding trustworthy data on the carbon emissions or general eco-friendliness of things like air travel and grocery shopping can be a challenge. But the data is out there. is a UK company with an all-in-one calculator that measures all factors in your life that contribute to your footprint. On the site, you can input data from day-to-day activities, such as your commute to work or your laundry habits. is similar to many Canadian companies (like CarbonZero and Carbon Tree) that sell offsets and have their own calculators.

We sometimes forget that air travel is one of the biggest contributors to emissions. While there don't seem to be many up-to-date or precise databases, you can still get a decent estimate of the emissions caused by flying.

A site called Blue Sky Model compiled data on airplanes from U.S government sources in 2002. It breaks down the emissions on "1 air mile" from popular models of airplanes (primarily manufactured in the U.S.). The site acknowledges their information is outdated, and encourages visitors to help provide reliable new data.

If you're planning a vacation, you might want to calculate the emissions for your trip. The International Civil Aviation Organization (ICAO), a UN agency, has an online calculator that estimates the emissions released based on your departure and arrival cities. The calculator is also available as an application for iOS devices.

At the grocery store, you undoubtedly come across a lot of environmentally friendly approval stickers (e.g. Leaping Bunny, Dolphin Safe) — but what do these labels really mean? And are they legit? You can get a list of these labels and a short summary of their standards on a site called Eco Label Index. It provides a list of more than 400 labels and can be broken down by country. (Here's the one for Canada.)

One way to make better decisions about produce is to use Localize, founded by Meghan Dear in 2011. Localize is an Edmonton company that allows you to scan the unique Localize barcode at participating supermarkets across Canada to learn about where it comes from.

"I'd love to see consumers take a little more interest in what these [certifications] mean and what they stand for," said Polina Pinchevsky, the founder of RoundPeg Benefit, a U.S.-based marketing consultancy that helps companies become more socially and environmentally responsible.

For example, "if you care deeply about the animals, why not buy chocolate that's Rainforest Alliance-certified and support your issue with your purchase?" Pinchevsky said.

You actually don't need to put in much effort, either. The app CoGo (short for "Connecting Good") helps you find local, ethical and sustainable businesses that match your values. For more ideas on how to consume consciously, RoundPeg has an extensive list of companies working towards conscious consumerism.

Pinchevsky said that businesses work hard to meet the standards of most certifying organizations. "Consumers can play a bigger role in learning what these certifications mean and support companies that are certified."

Farhnaz Fazli

What's on your mind?

Our story on passive houses last week garnered a lot of interest, as well as some emails pointing out that we'd neglected to mention a key Canadian connection. During the 1970s oil crisis, the Saskatchewan government commissioned the building of a concept home that used solar power and was ultra-efficient. The result was the Saskatchewan Conservation House, which was studied by German engineers and helped propel the passive house movement.

Email us at

Weighing the environmental benefits of nuclear energy

(Richard Hertzler/LNP/LancasterOnline via AP)

Climate change is forcing us to find ways to produce clean energy — and fast. Though much attention has focused on renewable sources like solar and wind, some are touting nuclear power as another source to consider.

Last week, U.S. Energy Secretary Rick Perry referred to greater funding of nuclear power as the "the real green new deal." Those in favour of more nuclear power say it's much cleaner than burning fossil fuels, and that it's the only energy industry that takes care of its waste.

But it's not the whole story.

"Like any energy technology, it has aspects that are cleaner and aspects that aren't so clean," said Edwin Lyman, acting director of the U.S.-based Union of Concerned Scientists' nuclear safety project.

For one, it generates radioactive waste that can last for thousands of years. And getting rid of it isn't easy.

Nuclear power plants work by splitting uranium atoms, a process called fission. The uranium is in the form of pellets that are sealed into metal rods and stacked. The heat generated by fission converts water into steam, which in turn spins a turbine or generator that creates electricity.

After the uranium is expended, the rods are placed in a cooling tank of water for anywhere between seven and 10 years. After that, they are placed in dry storage containers of reinforced high-density concrete, which seals against radiation leakage. The problem is, those containers only have a lifespan of 50 years. According to Canada's Nuclear Waste Management Organization (NWMO), after that, the container may have its life extended or the fuel could be repackaged.

According to the Canadian Nuclear Safety Commission, Canada has five plants (and a total of 22 nuclear power reactors), which produce roughly 15 per cent of Canada's electricity. As of June 30, 2017, Canada had about 2.8 million used nuclear fuel bundles, which NWMO says could fill eight hockey rinks from the ice to the top of the boards.

Then there's the concern over leaks, or worse. Radiation from the worst nuclear disaster in history — in Chernobyl, Ukraine, in 1986 — forced 220,000 people to leave their homes. It's still unknown how many people died as a result. The World Health Organization estimated in 2005 that it could be up to 4,000 people, but an updated study released in 2016 estimates it could be much higher — thyroid cancer alone could account for close to 11,000 deaths.

Aside from leaks and explosions, there's also concern over terrorism, and countries using the uranium to make nuclear weapons.

Lyman noted that all energy technologies come with risks and consequences, but acknowledged that "nuclear power has some unique aspects compared to renewable energy technologies that make it less desirable."

The Nuclear Energy Institute in the U.S. says the public doesn't understand how safe the technology is. But Lyman said that "a lot of experts have their own biases that they can't see past."

He said members of the public should ensure they're getting good information, and consider all options, including risk.

"It doesn't make sense to say, by fiat, 'no nuclear power,'" Lyman said, but "you have to value it and consider its risks appropriately."

Nicole Mortillaro

The Big Picture: Global per capita energy use

This weekend is Earth Hour, in which people worldwide are encouraged to switch off their lights for 60 minutes as part of a larger effort to raise environmental awareness. It led us to wonder: Just how much energy do we use, globally? According to 2014 statistics from the International Energy Agency, the biggest consumer per capita is ... Iceland? Indeed. The country is rich in hydro and geothermal energy, and apparently not shy about using a lot of it. In Iceland's defence, its energy sources are 100 per cent renewable.


Hot and bothered: Provocative ideas from around the web

  • The Danish city of Copenhagen wants to be carbon-neutral by 2025. It's an ambitious target, and not without its challenges. But this article points out that as more and more human beings choose to live in cities, urban areas will be forced to embrace bold carbon-cutting initiatives.

  • There is much talk in Canada about the need to help workers in carbon-intensive industries transition to clean-energy jobs. This beautiful New York Times photo essay relates the stories of a number of Americans employed in the coal and petroleum industries who, as a result of economics, health or climate conscience, now work in renewables. As one man puts it: "Pursuing my family background in oil was not the way to go."

  • Alberta has a new wildland park: Kitaskino Nuwenëné. This 161,880-hectare area north of Fort McMurray is intended for traditional use by Indigenous peoples, and was established after negotiations with Indigenous groups and the Alberta government prompted three major oil and gas companies to give up their leases.

How you're living a greener life

(Romeo Gacad/AFP/Getty Images)

Around the new year, we asked readers what sorts of resolutions they had made to live more sustainably. Here are some of your responses.

"I'm bothered by all of the plastic packaging and produce bags in grocery stores," wrote one reader. "I always go for the fruits and vegetables that aren't in any packaging, and I bring my mesh produce bags and reusable grocery bags with me every time."

This reader also made a larger point: "How do we get grocery stores to make the change? I tag them in Instagram posts all the time on articles on zero waste and bulk buying, etc. But I don't see change. People are unconscious and/or lazy, so they continue to use and buy foods in plastic, so I think the grocery stores need to take those options away from them."

Andrea McFadden said foregoing plastic packaging has become natural for her.

"It is actually not difficult to say, 'No, thank you' when you are offered bags [at a store], to choose not to purchase foods wrapped in plastic and on Styrofoam trays or beverages in plastic jugs." She said she has also returned to using "laundry soap in paperboard boxes."

Liz French wrote to say she has been "using reusable produce bags (available on Amazon) while shopping for fruit and vegetables, instead of the plastic bags supplied at the store."

She also made an effort to reduce plastic bag use at home. "We have been keeping our wet garbage (meat and vegetable scraps, meat packaging, etc.) in the fridge or freezer during the week, so that we only have to use one plastic bag per week. I'm not sure if this would work for a larger family due to fridge space, but it works well for the two of us."

Stay in touch!

Are there issues you'd like us to cover? Questions you want answered? Do you just want to share a kind word? We'd love to hear from you. Email us at

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Editor: Andre Mayer | Logo design: Sködt McNalty


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