Why should we care about our carbon footprint?

In general it is a good way to see how we stack up, are we doing out part to reduce pollution. Everything we do, use, buy and consume has an impact on the planet, both in the resources used and the waste/pollution it creates. I haven't found a very accurate calculator yet, but I think many of the online calculators are a good place to start to see how various activities impact our contribution to global pollution.