.

The graph above shows the amount of CO2 emissions in kilograms per person. As you can see, travelers using privately owned vehicles to have someone to take them to the airport are emitting the most CO2 per person each time they come. These figures make sense because the vehicle will emit carbon dioxide going to the airport, dropping their traveler off and then driving back home. This is twice the amount of a taxi or parking because those vehicles aren't going back anywhere so they don't need to emit more CO2.

However, a method such as the Light Rail, Shuttle Express and parking are green methods. They emit very little amounts of carbon dioxide per person. It's less than 20% of the amount that drop off vehicles give off! The Port of Seattle and S.T.E.P. intend to decrease the amount of people using that method of transportation and increase the amount of people using more environmentally preferred methods.

Seattle-Tacoma Airport has already taken a few steps towards a more environmentally friendly airport with their recycling programs and usage of an oyster water filtration system. But they want to keep going on this pathway to become a sustainable, environmentally friendly and efficient airport.