Carbon & Environmental Import Tax
Carbon taxing your own industries while not taxing imports, makes no sense. Rewarding companies that don't produce in your own country and instead move offshore where there is little to no regulations is the opposite of being environmentally friendly. Inter country trade shouldn't be carbon taxed at all, import carbon taxes is what we should be focusing on. Rewarding companies and countries that move manufacturing offshore and then import all their goods is worse than a company or countries that produce at home under stricter environmental regulations. Focusing more on consumption instead of production makes more sense as well, although taxing Canadians to heat their homes is a bit ridiculous.
Environment import taxes is what we should be looking at, we should also be looking at more than carbon dioxide emissions. How a country keeps care of its natural habitat, its endangered species, how much they throw away, how they treat their waste water and how they treat their citizens should also be factored in. Taking all of this into account is the only way to make a government and their citizens act appropriately.
Having a real economic reason, that you can measure, is the only way to convince other countries, companies and governments to act in favor of the environment. This would also stop other countries from interfering with Canadian internal affairs aka, no foreign governments paying protestors to protect their own interests.
A global import environmental tax that is supported by many of the top countries would quickly slow down many of the worst offenders. It would also give countries real targets and real reasons to reach those environmental goals. It wouldn't matter that there is a lack of binding enforcement mechanism, because the import taxes would be incentive enough for most countries to get their shit together.
Carbon Import Tax
There is no maximum import rate, but most would be paying around 5% to 8% (excluding those with rampant human rights and environmental abuses). The starting (and minimum) import rate would be the same as the GST (5%), but that can be raised or kept the same depending on how the country keeps care of their environment and their people.
Human Rights: Any country that doesn't have reasonably fair laws, equal rights for their citizens or isn't a free country, would see their import rate double from the standard rate for each offense type. For example, if a country has a law that says you can have your wife stoned to death if she is raped, while killing members of a different religion and is ruled by a king, the initial import rate would start at 40% (5% x 2 x 2 x 2 = 40%). Seriously, I don't know how Canadians in the east can fill their gas tanks without vomiting a little in their mouths each time.
Wide spread genocide would automatically stop the country from importing into Canada.
Natural Habit and Protected Species: An import rate increase of 50% would occur for each large animal and/or fish that is either endangered or supposed to be protected, but is not being adequately protected. So, Japan's whaling would increase their environment import rate to 7.5% (5% x 150% = 7.5%).
For the habitat portion, a country will have their import rate increased by 100 basis points (1%) for every 35,000 hectares of land or for every 1% of land (whichever is greater). This is for either protected natural park land or forested land that isn't replanted. This rate is cumulative throughout the years. So, a country such as Brazil, that clear cuts their forests would have an ever-expanding import rate increase each year and it would increase each year until they start replanting their forests.
CO2 Emissions: The formula for calculating CO2 emissions would be (Industry value added of the country per capita) ÷ (CO2 (tons) emissions per capita). You do this so you don't punish countries that produce and you don't reward countries that only seem to consume. The import rate would decrease or increase depending on whether the ratio is higher or lower.
A production carbon import tax of $50+ a tonne should be added to high CO2 emission products such as crude oil and refined products. The CO2 emission import tax rate would either be the country rate or the production rate, whichever is higher.
How Much a Country Wastes: Was going to use the recycle rate, but went with how much ends up in the land fill per capita, because it rewards countries that also reduce or use less in the first place.