Carbon footprint

A carbon footprint is an estimate of the climate change impact of activity – such as making a product, living a lifestyle or running a company.
Typically, a carbon footprint is calculated by estimating not just the CO2 emissions that the activity in question causes, but also any emissions of other greenhouse gases (such as methane and nitrous oxide) and in some cases other types of climate impacts as well, such as vapour trails from aeroplanes. For simplicity, all these impacts are added together and expressed as a single number in terms of carbon dioxide equivalent (CO2e): the amount of CO2 that would create the same amount of warming.
Here you can calcuate your carbon footprint: http://www.carbonfootprint.com/calculator.aspx
(Hungarian average carbon footprint is 3.1 ha. In Etopia it is 0.5, in the USA 10.3 ha.)