This week, thousands of Manitobans have been leaving their cars at home as part of the Commuter Challenge ­ a week-long initiative that began June 1 and continues until June 7.

Coordinated locally by Resource Conservation Manitoba, the challenge runs in conjunction with Canadian Environment Week (yes, there is such a thing) and encourages people to find alternative ways to get to work or school.

It¹s a well-meaning endeavour for all the obvious reasons. Transportation accounts for a significant portion of Manitoba¹s greenhouse gas emissions -- in 2005, it represented 37% of our overall total -- which means that driving a car is one of the main ways individual citizens contribute to climate change and that, conversely, not driving a car is one of the main ways us regular folks can be a part of the solution.

There are other negatives associated with car use, too: air pollution, traffic congestion, excess wear and tear on our city¹s existing (and already crumbling) infrastructure, and a reduction in the amount of physical activity within our daily routines, just to name a few.

Last year, 12,881 people from more than 250 workplaces and schools across the province participated in the Commuter Challenge. Collectively, they prevented about 154 tonnes of GHG emissions from entering the atmosphere -- a noteworthy success, to be sure, and an encouraging sign -- particularly here in Winnipeg, a city that, historically, has been less than enthusiastic to embrace alternative transportation as a viable concept. (See: the kiboshing of rapid transit in 2004; the two years of foot-dragging prior to the adoption of our active transportation study last summer; and the lack of investment in commuter cycling infrastructure such as on-road bike lanes.)

Clearly, those attitudes are definitely changing. But, while the city may now be more willing to endorse drive-less initiatives such as the Commuter Challenge or the upcoming Bike to Work Day on June 20, and while increasing numbers of people may be more willing to participate in them, the fact remains that we citizens have yet to abandon our cars en masse.

This could be because the decks appear to be stacked against us. Our city is spread out, our current transit system is painfully slow and frequently inadequate, and prolonged bouts of freezing weather makes the idea of year-round cycling daunting, to say the least.

Still, I have a sneaking suspicion that our reluctance to change our behaviours has more to do with our unwillingness to inconvenience ourselves. We like our cars, we like the freedom they give us to get around quickly and with minimal effort, and we¹re just not prepared to sacrifice that -- even if we know we should; even if soaring gas prices have added a financial incentive to do so.

So what will it take for us to change our driving habits once and for all? What¹s the tipping point at which we finally say enough is enough -- and are we close to reaching it?

E-mail me at marlo.campbell@uptownmag.com and let me know your thoughts. Are you driving less nowadays -- or are you just feeling guiltier?