I admit: we aren't 100% sure that human activity is causing global warming.

So let's all go home in our SUVs and join an "axe the tax" campaign. Come to think of it, we aren't sure our houses will be robbed, flooded, or burned to the ground, so let's cancel our home insurance while we're at it.

After all, the vast majority of the world's climate scientists will only admit to being 90% certain that our carbon emissions are causing global warming on such a scale that we face global catastrophe if we fail to change our ways.

If nine out of 10 doctors said your child needed an immediate operation, would you wait until all 10 agreed? James Hansen, a leading climate expert who raised the alarm about global warming to the U.S. Congress 20 years ago, says he's 99% sure, but that's still not 100%, so why should we pay more by way of a carbon tax to address a problem that may not exist?

Never mind that countries such as Sweden, which implemented a carbon tax in 1991, have proven such measures are effective and actually produce economic benefits; why should we change if we don't have to?

Consider this: If industry shills and their followers are right and global warming is not the threat we think it is, and we act anyway, the oil will still be there for future use and we'll also have cleaner air and greater innovation in green technologies - along with stronger economies. If the majority of the world's climate scientists are right and we fail to act, we face ecological, social, and economic catastrophe on a scale beyond anything we've experienced in modern times.

Consider also that carbon taxes such as B.C.'s and the one the federal Liberals have proposed are actually tax shifts.

The money collected from individuals, businesses, and industry will be returned in the form of cuts to personal and business taxes, and may help us move away from continued reliance on increasingly scarce and costly fossil fuels.

Whether it's called a tax shift, a revenue-neutral tax, or a new tax, it will get people worked up. No one likes taxes, but we like roads and schools and hospitals and police services, so we pay them. We also pay about $90 a tonne to put garbage into landfills, so why are we so concerned about having to pay to put garbage into the air?

Politicians have two ways to influence behaviour: regulation and taxation.

In the mindless mantra of anti-taxation groups, taxes are bad and we should always cut and never increase them. The ludicrous aspect is that these groups are silent about the enormous taxpayer subsidies to fossil-fuel and related industries that make windfall profits.

Together with measures such as a cap-and-trade program, a carbon tax can use money from industries that are not energy-efficient to create economic benefits and incentives for those that are wiser in their energy use.

The income generated by a carbon tax can be used to cut income taxes, build more public transit, upgrade trains, develop renewable-energy sources, and retrofit homes and buildings with energy-efficient technology.

For 20 years, scientists have warned of the need for urgent action to reduce greenhouse gas emissions. Leading economists have shown that the cost to bring emissions down will be about 1% of GDP annually, while the costs incurred if we don't reduce emissions could be economically catastrophic.

When politicians, business people, and citizens show leadership by proposing or implementing solutions to the very real problems facing the planet (yes, more than 90% certain is as real as it gets in science), they deserve our support, not mockery and politically motivated misinformation. Axe the tax, my ass!

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