Can I travel without expanding my carbon footprint?

African Animal Image Gallery Ecotourists can stay at ecolodges, but how do they offset the emissions created by their flight to South Africa? See more pictures of African animals.
Clive Mason/­Getty Images

­In the last decade, ecotourism has exploded as a travel trend, now accounting for an astonishing 11.4 percent of consumer spending worldwide [source: GDRC]. Ecotourism is short for "ecological tourism," and it's a type and style of travel that has two primary, related goals: to minimize the environmental cost of tourism in general, and to actually provide ecological benefit to the travel destination.

Imagine, for example, a two-week African safari. An ecotourist might choose a housing destination that uses "green energy," recycles trash, has access to a water-treatment facility so it can reuse wastewater, uses only locally grown food (so it doesn't have to be shipped in from far away) and perhaps even donates a certain percentage of tourism profits to community-improvement projects. That would reduce the environmental cost of a typical African vacation. Going a step further, into benefiting the destination community, that ecotourist might choose to participate in those very community-improvement projects as part of the vacation.

­There's an inherent problem with even this high-level type of ecotourism: power requirements. Even with partially green-powered lodging, planes still fly on greenhouse-gas-emitting fuel. And the round trip flight from, say, New York to Tanzania is very long -- about 15,000 miles (24,000 kilometers). Then add in the gas-powered Jeep rides from the airport into the jungle and then from spot to spot within that huge tract of land, seeking out zebras and giraffes. We're talking about a whole lot of carbon dioxide emissions during that two-week trip.

This is where travel green tags come in. Green tags are carbon offsets -- the same thing you can buy from your power company to help reduce the environmental effects of your household power consumption. In the last five years or so, more and more travel companies have gotten in on the green tag trend to help travelers reduce the ecological effects of their trips.

In this article, we'll take a look at how green tags work and how they fit in with ecotourism. What exactly are you buying when you buy a carbon credit, anyway? And can they really make a gas-guzzling, 15,000-mile trip to Africa "carbon neutral?"