The United Nations estimates around 70 percent of the world's greenhouse gas emissions are produced in urban areas.
Its latest Climate Change report warns changes are needed to how cities are designed - to reduce emissions and improve resilience to severe weather events.
It's a transport system that is still in the works in Wellington - light rail.
It is just one solution in a multi-billion dollar transformational plan to fix congestion and reduce emissions.
"Let's get Wellington moving is the key project that we have to deliver in order to reduce our carbon emissions and meet our climate targets we've agreed to," Wellington City Council's Environment and Infrastructure chair Tamatha Paul told Newshub.
The climate targets include reducing the city's gross emissions by 57 percent by 2030 and eventually becoming net zero by 2050.
A key goal to combat climate change is an issue council are grappling with.
"The climate change story is [about] how to best use our spaces to serve all people. That looks like an efficient public transport system, high-density housing on good transport corridor routes. It's about having our green belt and nature all around us to act as a sponge," Paul said.
It's because urban areas contribute 70 percent of the world's carbon dioxide emissions.
"Basically it's because where all the people live. I think currently half of the world's population lives in urban areas," University of Waikato's climate change lecturer Luke Harrington told Newshub.
"By 2050 that's going to go up to two-thirds of the world's population."
Among the solutions highlighted in the IPCC report are supporting public transport and encouraging people to walk or bike, making new buildings - or retrofitting old ones to be more energy efficient. Reducing energy use and adopting low emissions sources of energy and planning communities so they're more densely populated to avoid urban sprawl - and people to be able to live close to where they work.
"Making cities more compact so you can access things to live a good life makes sense. one of the things that is really important to also remember though is that we need to make space for other things other than just the buildings," Harrington said.
"We need to make sure there is plenty of room for urban green spaces for example. that's really really important for a huge for a whole bunch of reasons. Some of which is building resilience to climate change."
For the good of our cities and the planet.
