What do residents of Stanford, Emeryville and San Pablo have in common? They are among the Bay Area’s lowest emitters of carbon, helping slow the warming of our planet.
Portola Valley, Piedmont and Alamo residents have a more dubious distinction, ranking at the top of carbon emitters, according to a UC Berkeley analysis that offers a stark revelation of how each Bay Area neighborhood contributes to global warming.
As mayors from around the world commit to climate action plans this week at San Francisco’s Global Climate Action Summit, the first-of-its-kind interactive map exposes our local winners and losers in the race to limit the increase in warming to 1.5 degrees Celsius (or 3.6 degrees Farenheit) over pre-industrial levels, by 2020. It quantifies communities’ carbon footprint — the total amount of greenhouse gas emissions that come from transportation, energy use and other sources. The gases trap heat in the atmosphere, causing global warming.
The map covers census block groups – neighborhoods of several hundred to a few thousand households – in the nine-county Bay Area. Neighborhoods with relatively high emissions show up as red, while low-emission neighborhoods are green.
The researchers calculated the carbon footprints based on household consumption, regardless of where on the globe emissions occurred. For example, if a computer was made in China but bought by a Berkeley resident, all emissions from the production of the computer were allocated to the Berkeley neighborhood.
Because transportation is such a large source of emissions, some neighborhoods have footprints three or four times larger than others, said Christopher Jones of UC Berkeley’s CoolClimate Network and lead author of the study, sponsored by the Bay Area Air Quality Management District. The calculation is based on use of cars, trucks and other gas-powered vehicles by the residents in a particular neighborhood.
The research, published online, can be used to target policies and programs to help similar communities speed up their adoption of carbon-efficient technologies, said Jones, 47, a Davis resident who rides his bike to work and shares an electric car with his wife.
For example, some communities could build more environmentally friendly, high density housing near transit while others could install more solar panels or encourage a switch to electric cars.
The best way to reduce emissions in the Bay Area is to massively scale up electrification of our vehicles and our heating, said Jones. Those changes would reduce most cities’ carbon footprint by 30 percent, he said.
“Our goal,” he said, “is to provide the resources to local residents and governments to understand which options have the most potential to reduce greenhouse gas emissions — and what matters least.”
Cities are critical to the effort. Although they represent just two percent of the world’s land area, they account for more than 70 percent of carbon pollution.
In the Bay Area, transportation is the largest source of households’ emissions, representing 33 percent of the total, the team found. That was followed by food (19 percent), goods (18 percent), services (18 percent), heating fuels (5 percent), home construction (3 percent), electricity (2 percent) and waste (1 percent).
But in some urban cores like Oakland, where emissions from transportation are low, meat consumption contributes roughly an equivalent amount as vehicles, the researchers found, because livestock farming produces large amounts of greenhouse gases.
In suburban cities, such as Alamo, transportation-related emissions are upward of three times higher than in urban core areas. Surbanites tend to emit more greenhouse gases because they own more cars and larger homes, Jones said. Urban residents, on the other hand, tend to drive less and live in smaller homes and apartments. At Stanford, for instance, many students and faculty walk or bicycle to class.