More people are beginning to move to urban centers and away from rural towns. With this, comes a large flow of migrants coming in to previously established cities. The more people that become a part of a city's population the more need there is to have a sustainable and therefore "happier" city. To achieve this increased sustainability, there are several possible avenues in which governments can explore. 

The first of which is the mass investing in public transportation. Looking at transportation, its quite clear that without a centralized system a city cannot function at full capacity. As a result, most cities are built around public transit. Without public transport, working class individuals would need other ways in which to travel from home(usually in the suburban area) to work(usually in the cities). Unfortunately, the only when they see fit is to buy a Car and drive to-and-from work everyday. This a fundamental issue that needs to be slowly eradicated as the carbon emissions per person is much less if a group of people take a bus or train rather than each individual taking their respective car. Furthermore, the revenue received from these services can either be invested back into the infrastructure of the city or improving/expanding the public transportation to make it even more sustainable. The importance of a pubic transportation is, in most places, considers as an essential service rather than an amenity.

Another idea is green infrastructure. In Colorado, there is something called a "Green Roof Initiative" where residents plant greens/plants on top of the building. The effect is such that it reduces flooding and increases water availability for the city. 

Quick Explanations

1. Reduces Flooding:

The soil in the green roofs work as a sort of sponge that absorbs the water that would normally be wasted or flood onto the streets. 

2. Reduces the Urban Island Effect:

The Urban Island Effect is essentially the fact that Urban cities are warmer than rural ones due to human activities and modifications to the land. By implementing a green roof, the added vegetation  can reduce temperatures and moderate the heat effect. 

As we look into the future, it's important to incorporate more green infrastructure within our cities since it's another opportunity for us to demonstrate our resilience to climate change and begin to tackle it city by city.