Resorts will begin to offer "eco-discounts" for guests who book rooms outfitted with low-flow toilets and showerheads, compact fluorescent lighting, and other energy-saving devices.

In 2008 Indianapolis opened a $1.1 billion international airport with electric runway vehicles and a massive sunroof to maximize natural light. Expect more eco-minded hubs to follow.

Metropolitan hotels like New York’s Grand Hyatt will set the benchmark for environmental best practices with organic banquet menus, nontoxic cleaning products, in-room coffee bar utensils made from potato starch, and more.

More travel industry heavyweights—including British Airways, Hilton Hotels, and Royal Caribbean Cruises—will commit to large-scale carbon emissions reduction.

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