By 2050, nearly 70% of people are expected to live in cities. This growing urbanization makes people like former New York Mayor Michael Bloomberg think that climate change can be overcome.

In a new book, “Climate of Hope: How Cities, Businesses, and Citizens Can Save the Planet,” Bloomberg and Carl Pope, the former executive director of the Sierra Club, join a chorus of other proponents making the case that cities are uniquely positioned to combat climate change for several reasons.

First, cities sharply feel the effects of climate change and pollution and are therefore incentivized to act.

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“Emotionally you can think of the polar bears and the warming Arctic, but when push comes to shove it still seems a bit distant,” John Rennie Short, urban policy expert at the University of Maryland Baltimore County, told Global Citizen. “But the air quality in your city is definitely a real issue.”

Cities throughout the world from Mexico City to Beijing are suffering from extreme air pollution and this is spurring citizens to call for action.

Image: Flickr: Josh

Many of the world’s cities are also located on coastlines that are endangered by sea level rise and erosion. Cities like New York, London, Shanghai, and Guangzhou could be submerged in the next several decades. These places hold tens of millions of people and are economic linchpins in national economies, making their future viability important to state and federal governments.

Second, cities in the world are both intensely competitive and collaborative.

All the major cities vie for the world’s best companies and workers and their competitive edge increasingly hinges on sustainability — the cleanliness of air and water and the eco-friendliness of infrastructure and transportation systems.

"Companies and investors recognize that the low-carbon economy is inevitable and necessary to avoid the most devastating impacts of climate change not just on our environment, but on our economy," said Katina Tsongas, senior manager of policy at Ceres, a nonprofit that promotes corporate sustainability. 

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Cities regularly trade best practices for managing emerging problems like climate change. Bloomberg, for instance, is the president of C40, a collective of 80 powerful cities that fosters innovation and collaboration.

“There’s a constant laboratory of examples,” said Short. “Different cities trying different things, and other cities learning from them. Technology is transferrable, knowledge is transferrable, consultants move around, there’s a global circulation.”

Image: Flickr- City Clock Magazine

Third, cities are able to act more swiftly than state or national governments because mayors are in more direct dialogue with citizens.

A mayor can more rapidly enact energy efficiency standards, promote the use of electric vehicles, and ban practices and systems that cause emissions.  

Finally, cities can also exert influence on supply chains. If a city insists that all of its energy comes from renewable sources, it pressures suppliers to invest in renewables.

While countries are working to increase the overall capacity of renewables, fossil fuels still provide the bulk of energy needs.

And it will likely be decades before renewables can plausibly overtake fossil fuels — by then, the damage already wrought on the environment will be enormous.  

That’s one of the criticisms lobbed against Bloomberg’s argument. In fact, many critics — from both the urban policy and environmental fields —  argue that cities aren’t in a position to credibly fight climate change and that the real focus needs to be on the national and international level.

Oftentimes, cities are occupied with mitigation rather than adaptation, two goals that aren’t always aligned. For example, preventing sea levels from flooding streets has nothing to do with halting emissions. The former saves the infrastructure of a city, the latter saves the planet, yet budgets are often allocated to the short-term rather than the long-term, as a trio of scholars recently argued.  

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Cities also have an unusual relationship to emissions.

“It’s important to understand that the carbon footprint of a city is quite unique, and quite heavily subsidizes carbon-intense activity elsewhere,” Oren Cass, a senior fellow focusing on energy and the environment at the Manhattan Institute, told Global Citizen. “When you hear a city showing off how low they can bring their carbon footprint, it’s important to understand what they are and aren’t counting. They’re essentially the low-hanging fruit, they’re not solving any of the underlying challenges.”

Oren said that nearly all the food, products, and infrastructure materials consumed in a city are produced elsewhere at enormous ecological cost. So, for instance, New York’s pledge to cut its emissions by 80% by 2050 isn’t as impressive as it seems.

Image: Unsplash/ Pixabay

“Something that makes New York’s pledges something of a PR pledge is it’s not really counting its emissions footprint appropriately,” Cass said. “The fact that you can do investment banking with a very low carbon footprint isn’t notable or impressive."

Perhaps the biggest blow to city-centric argument is the fact that most of the emissions in the future will come from developing nations.

About 80% of the energy capacity that the developing world needs by 2050 hasn’t even been built yet, according to Cass, and the bulk of this capacity is dependent on fossil fuels.

He believes that the Paris climate accords barely address this energy demand.

“It’s a perfect illustration of how hard this is to do,” Cass said. They all just committed to do business as usual. None of them actually committed to shifting their emissions trajectories at all.”

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That’s been the overarching critique of the accords. While they finally brought about a global framework for confronting climate change, there are no mechanisms in place to enforce the targets of keeping temperature rises from the industrial age under 2 degrees Celsius.

And emissions are not falling on their own.

But champions of the city model like Bloomberg are undeterred and think that cities have the ability to flip the status quo.

Currently, the world subsidizes the fossil fuel industry at a rate of $5 trillion each year.

If cities forced state and federal governments to shift these subsidies to industries that actually promote the health of the planet, then everything could change.

As Bloomberg wrote in a New York Times op-ed last year: “Washington will not have the last word on the fate of the Paris agreement in the US – mayors will, together with business leaders and citizens.”


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