(Test Drive: Carbon Footprint Calculator) Some scientists believe that carbon emissions, especially from the burning of fossil fuels, contribute significantly to global warming and that this can be combatted if individuals take steps to limit their use of carbon-based fuels .Organizations and individuals are increasingly concerned about their “carbon footprints.” Websites such as TerraPass www.terrapass.com/carbon-footprint-calculator/ and Carbon Footprint www.carbonfootprint.com/calculator.aspx