One especially important factor in creating a sustainable city and limit carbon emissions is to clean up and advance upon transpirational systems. One way of helping the transportation system would be to encourage the use of public transportation. In a sustainable city, it is important to have busses/trains not only for convenient and low cost travel but also to help lower the amount of people driving cars, which would help to keep carbon emissions low. To increase the amount of people using public transportation, a sustainable city should figure out city hotspots and create routes that travel through those areas. One city that works out this system quite efficiently is New York City. An article by NextCity titled "Can New York’s Transit Authority Lead the Way to a Carbon-Efficient Future?" states that "Each year New York City’s public transit system keeps millions of metric tons of greenhouse gases out of the atmosphere." A sustainable city should mirror or take example from this system in forming their own systems. Personally, when I was visiting New York City, I noticed that the public transit systems were even faster than driving as the city is highly populated and many people drive. Some methods that could be used to increase foot traffic in public transportation are advertising, cleaning, and increasing the size of trains and other methods of transportation. These transpirational ideas should be taken into account when creating a sustainable city.