Suburbs Stomp On City's Eco-Savings with their own Carbon Footprint
According to a new study by UC Berkeley researchers, population-dense cities contribute less greenhouse-gas emissions per person than other areas of the country. This reasoning seems to makes sense because of resources like public transportation that cut down carbon emissions and shared heating and electricity costs that save on energy. But with every city comes its suburbs and these areas essentially stomp out all environmental benefits that dense cities provide with their own carbon footprint.
According to a UC Berkeley study, suburbs in the United States account for about 50% of all household emissions even though they account for less than half of the US population.
The study uses local census, weather and other data to approximate greenhouse gas emissions resulting from the energy, transportation, food, goods and services consumed by U.S. households, so-called household carbon footprints.
"The goal of the project is to help cities better understand the primary drivers of household carbon footprints in each location," said Daniel Kammen, director of the Renewable and Appropriate Energy Laboratory. "We hope cities will use this information to begin to create highly tailored climate action plans for their communities."
"Metropolitan areas look like carbon footprint hurricanes, with dark green, low-carbon urban cores surrounded by red, high-carbon suburbs," said Christopher Jones, a doctoral student working with Kammen in the Energy and Resources Group. "Unfortunately, while the most populous metropolitan areas tend to have the lowest carbon footprint centers, they also tend to have the most extensive high-carbon footprint suburbs."
The UC Berkeley researchers found that the primary drivers of carbon footprints are household income, vehicle ownership and home size, all of which are considerably higher in suburbs. Other important factors include population density, the carbon intensity of electricity production, energy prices and weather.
As to which is better, increasing population density within cities versus increasing it in suburbs? Neither seems to be a solution as only a 10-fold increase in city density will yield only a 25 percent reduction in greenhouse gas emissions, and dense suburbs have an even higher footprint than less dense suburbs.
Instead, the authors say the focus should be on tailoring climate solutions to demographically similar populations within locations.
"Suburbs are excellent candidates for a combination of solar photovoltaic systems, electric vehicles and energy-efficient technologies," said Kammen. "When you package low-carbon technologies together you find real financial savings and big social and environmental benefits."
Read more at UC Berkeley News Center.
Suburb image via Shutterstock.