These are all terms thrown about in today's world in response to global warming admonitions. All across the globe, "green" is the new trend, and everyone from corporations to business and leisure travelers is considering "carbon offsetting" as a way to reduce their "carbon footprint."

What is it?

Carbon offsetting is part of a carbon neutral lifestyle to send the right message and do good and go green. According to Wikipedia, carbon offset is a financial instrument representing a reduction in greenhouse gas emissions, and in 2006, about $91 million of carbon offsets were purchased in the voluntary market, representing about 24 million metric tons of CO2e reductions.

According to Brian Mullis is President and Co-founder of Sustainable Travel International (STI), a non-profit global leader in sustainable tourism development. STI takes a holistic approach to addressing sustainable development within the travel and tourism industry, providing tangible, solutions-oriented programs. According to Mullis, "Supporting legislation that requires mandatory greenhouse gas reductions is a first best solution, reducing CO2 emissions (such as driving more efficiently and using less electricity) is a second best solution, and offsetting unavoidable emissions is a third best solution."

How does it work?

Carbon is typically generated from greenhouse-gas emissions, like that which is emitted by airplanes, motorized vehicles, hotels, etc. Your "carbon footprint" is your impact on the environment based on those emissions, and carbon offsets are what you purchase to reduce that impact. Over 200 types of projects are suitable for generating carbon offsets, which are grouped into broad categories. The most common categories are renewable energy, methane abatement, energy efficiency, and fuel switching. Carbon offsets basically help you neutralize the pollution (greenhouse gases) you cause. Although there are six categories of these gases, in essence, one carbon offset equals the reduction of one metric ton of carbon dioxide, or its equivalent in other greenhouse gases.Carbon offsetting works by calculating the impact of your travel through a series of programs. Offsets are purchased based on that calculation. For example, an airline offset program provides a Web calculator that estimates a traveler's carbon dioxide emissions from the flights they book. The formula takes into account distance traveled and how much fuel is burned, which determines the amount of carbon emitted. Besides non-profit organizations like STI, hotels, airlines and other transportation companies are providing calculators and/or options to purchase offsets.

What is the actual benefit?

The actual benefit produced by carbon offset companies is difficult to judge as so many factors figure into the final results. Take tree planting, for instance. Trees theoretically absorb carbon dioxide from the atmosphere, including jet engine exhaust. However, environmental experts state that trees absorb carbon at different rates depending on location, weather, climate zones, possible disease and natural disasters - basically the impact of Mother Nature.

What does it cost?

Carbon offsets are surprising affordable and simple to calculate. Ecobusiness gives several examples of price points. For instance, driving a mid-sized car 12,000 miles per year creates 3.55 tons of CO2 per year. The carbon calculator tallied a cost of only $1.63 per month to offset that price.

Environmental Saver or Wallet Drainer?

There is no debate among scientists about the basic facts of global warming, according to the Environmental Defense Fund. In fact, the most respected scientific bodies have stated unequivocally that global warming is occurring, and people are causing it by burning fossil fuels (like coal, oil and natural gas) and cutting down forests.

When you buy offsets, you are paying someone to reduce or remove global warming pollution in your name.According to the Environmental Defense Fund, the prices range from $4 to $8 per metric ton.

Recommended Carbon Offset Sources

Besides STI (Web: http://www.sustainabletravelinternational.org/ Skype: sustainabletravel), a team of experts from The Environmental Defense Fund evaluated offsets and offers the following list that met their standards for credible, high-quality offsets:

• Natsource LLC - DuPont - Blue Source

• e-BlueHorizons SM

• Carbonfund.org

• AtmosClear Climate Club

• Carbon Calculator for Personal Impact

Just like any major purchase, it's best to first shop around, ask questions, and get referrals.

The Bottom Line

Offsetting your carbon emissions is really not the primary goal. Everyone agrees that we need to prevent and reduce our overall your emissions. Whether you are a frequent or infrequent traveler, or never leave your city, STI's Mullis says that we can all help. "We can all travel more thoughtfully, conserve electricity and generate less waste, but some CO2 emissions are unavoidable. This is when investing in credible renewable energy and energy efficiency offset projects to offset our emissions makes sense. Addressing the challenge of global climate change will require a sustained effort for many years to come."