Editor's note: Welcome to Grist's presentation of Alex Steffen's new book Carbon Zero. We'll be posting a new chapter every day till we're done -- here's the full table of contents. And this post will tell you a little more about the project. If you like what you read, you can order Carbon Zero from Amazon.
Urbanism: Why good walksheds mean lower emissions
How we build our cities determines how we live in them.
If we are going to imagine a carbon zero city, in most cases we need to start with a fresh understanding of how we get around in them. Transportation, after all, generates the largest share of humanity's greenhouse gas emissions. Cars account for most of that, but it's not just driving cars that's causing those emissions. Though the oil we burn driving is a catastrophic problem in its own right, those emissions are only part of the climate impacts of a huge set of systems that enables our driving. Factories and dealerships, roads and highways, parking lots and gas stations, road repairs and wrecking yards -- put them all together, and these "automotive systems" represent the single biggest contributor to global climate change worldwide.
So, getting a 90 percent reduction in transportation emissions is a serious job no matter where we live. But it’s a giant task in many North American and Australian cities, where car ownership and use (and thus emissions) are far higher than in cities elsewhere, and where most planning decisions were made with car traffic foremost in mind.
One thing is clear: We can’t get to new possibilities with old thinking. Turning the ignition key and starting our car -- no single act more defines the 20th century’s idea of prosperity, or offers a sharper contrast to the realities of the 21st century. Business-as-usual forecasts predict the world’s car fleets will double or even triple by mid-century. Car companies, with their old assumptions, see nothing but growth ahead. If their assumptions were right, there would be no way we could drop transportation emissions by the roughly 90 percent we seek.
What about electric cars, though? Can’t we just make all our cars electric and be done?