While it may be an extreme move for some, quitting or refusing to fly when travelling is said to lessen one's carbon (dioxide) footprint, thereby helping to mitigate the release of carbon dioxide into the atmosphere. Some environmentalists have pushed for a reduction in flights and have suggested other means of transportation. Germans, for instance, have been advised to substitute exotic travel destinations for more local and less exotic Baltic sea destinations. "In the near future, people are going to become increasingly aware that aircraft emit vast amounts of greenhouse gases, far more than cars or trains," said Manfred Stock, a climate researcher in Potsdam near Berlin.
Still, even if you take a ship or a car to get from point A to point B, you would still use fuel and release carbon dioxide, unless the vehicle you're riding in is some kind of next-generation transport that does not use fossil fuel.