Hundreds of millions of people travel overseas each year, and a good many of them fly to other continents. The impact of tourism on the the Earth's environment has become massive, not least because air travel generates carbon dioxide. What's more, jet-aircraft contrails exacerbate global warming. Like clouds, they stop infrared radiation reflected by the Earth's surface from going off into space, trapping it in the atmosphere. But if you don't have a yacht and the time needed to sail it across an ocean, you probably have no choice but to take an airplane if you want to experience distant lands and cultures.

Qantas 747Credit: Wikimedia Commons

Don't forget the basics

Wherever you're going, the steps you should take to minimise the environmental impact of your vacation or business trip aren’t so different from what travellers everywhere should be doing. Each time you make a purchase, return bags or excess packaging.

In your hotel room, adjust the air-conditioning so energy consumption is reduced. There's also a selfish reason to do this: You're less likely to catch a cold; the smaller the difference between room temperature and outside temperature, the less of a shock it is to your body when you venture outside. If you're not going to use the refrigerator, disconnect it if possible - and suggest to the management that they keep all friges disconnected unless notified by guests who plan to make use of them. Try not to waste water ("If it's brown, flush it down. If it's yellow, let it mellow"). Additionally, separate your trash so as much as possible can be recycled. If there's only one garbage can, leave obviously recyclable items such as beer cans, wine bottles and newspapers on the floor next to it, so housekeeping staff can dispose of those items separately.

Green hotels which incorporate sustainable architecture and which follow ecofriendly principles now operate in many parts of the world.

BusCredit: Wikimedia CommonsPublic transportation is obviously better than driving a rental car or taking taxis. Buses and trains will also save you money but, of course, aren't so flexible. Consider walking or cycling - better for you as well as being the best possible option for the environment. What's more, you'll get more chances to interact with locals, and you'll likely see things you'd otherwise miss.

To minimize food miles, eat local foods rather than imported produce. This way, you'll also be bolstering local agriculture. In hot countries, it's essential to drink plenty of liquids. Instead of buying several bottles of mineral water each day, bring a nalgene bottle (good for hot as well as cold drinks) and refill it at public water fountains. In the Philippines there are places where you can fill containers with filtered water for a very small amount of money. Unfortunately, these are usually in residential areas rather than in neighborhoods frequented by tourists.

Do your homework

Before leaving home, try to find out if there certain types of food which you should avoid to protect local ecosystems. For instance, is the seafood taken from coral reefs? Is fishing done in a sustainable manner? Is all the beef imported, or is it possible for steak addicts to get a fix without adding thousands of food miles to their carbon footprint?Disposable chopsticksCredit: Wikimedia Commons

If the country still uses a lot of disposable tableware, such as the cheap bamboo chopsticks favored by eateries in many parts of Asia (the picture here shows a trash can full of them in Japan), do carry your own cutlery. If you're heading to Thailand, consider carrying a plastic box roughly the size of an iPad. The chopped fruit sold by streetside vendors in those countries is delicious and healthy, but always comes in a plastic bag. With your own box you can enjoy it morning and afternoon without a plastic bag being added to the garbage tip each time.

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