You probably already know that increased greenhouse gases in the air – like carbon dioxide – are linked to climate change. If you want to cut down on the greenhouse gases you put in the air, what’s the best way to do it? EarthSky spoke with Chris Jones, a University of California-Berkeley expert on consumer behavior. He said:
Every dollar we spend on transportation, energy, food, water, and waste, all of that leads to emission of greenhouse gases somewhere on the planet.
Jones is lead author of a study in the Journal of Environmental Science and Technology in 2011 that helps pinpoint the most effective actions people in the United States can take to reduce their contribution to greenhouse gas emissions. The study analyzed consumer data from thousands of households across the U.S. Jones told EarthSky:
Luckily, we found some rules of thumb. Transportation, it turns out, is the single largest contributor across all different locations. So buying a more fuel-efficient vehicle is the single most important action most households can take.
Food is also an important contributor for all household types. Reducing consumption of red meat and dairy is an important opportunity. Cows release methane, and that is a 25 times more potent greenhouse gas than CO2.
Curbing home energy use can be key to reducing your household’s greenhouse gas emissions if you live in a region that depends heavily on coal for power – but there’s no one-size-fits-all approach, Jones said. That’s why he and his colleagues built a personalized online carbon calculator. Plug in your location, answer a few questions about your household size and lifestyle, and get tips about how to limit your greenhouse gas emissions.
Jones referred to the unique contribution of individuals and households to global carbon emissions as “carbon footprints” – people make these “footprints” with their water use, energy use, food consumption, transportation, and sundry purchases.
In all, Jones said his study analyzed typical household carbon footprints in all 50 U.S. states, 28 regions, six household sizes, and 12 income brackets. The cities Jones studied included San Francisco, California, St. Louis, Missouri, and the New York metropolitan area. While he found that there were certain rules of thumb when it came to reducing a household’s carbon footprint, there were some generalizations that couldn’t be made across the board. He explained:
Home energy efficiency is important in reducing your carbon footprint, but it depends on where you live in terms of carbon benefit. So if your energy is produced with coal, there are much greater emission-reduction opportunities than if your energy is produce with relatively clean sources, like natural gas or hydro.
He gave more examples of some other typical differences between households’ contributions to carbon emissions.
We considered an upper-income two-person household living in San Francisco, and air travel and gasoline consumption were by far the largest contributors to that household’s carbon footprint. The middle income or lower-middle income five-person household living in the Midwest has a completely different carbon footprint. It’s not transportation – it’s household energy, and food.
He clarified that transportation is a large contributor to greenhouse emissions in the U.S. Midwest – it’s just that transportation represented a lower percentage of contributions to greenhouse gases per household, relative to other emissions contributions.
And so when we’re designing policies and programs aimed at these household types, we want to try to figure out what are the most important sources of emissions, and what would be the most attractive opportunities for this household to reduce their emissions.
His real hope, he said, is that his data – and the carbon calculator his team devised – are going to be used by local governments, communities, and schools.
I really believe that local community-based action is the greatest opportunity here because the barriers for people to take [emissions-reducing] actions depend on different locations. Community groups have the best ability to determine what those barriers are, which could be lack of access to public transit, lack of perceived community support for these measures.
Listen to the 90 second EarthSky interview with Chris Jones on the best ways to reduce your greenhouse gas emissions (at top of page.)
Beth Lebwohl researches, writes and helps produce science content in audio and video formats for EarthSky. She is one of the authors on EarthSky.org, a script-writer for our podcasts, and helps host our English science podcasts in 90-second, 8-minute and 22-minute formats. Beth came to EarthSky in 2006 from the American Museum of Natural History's Department of Astrophysics, where she was surrounded by some of the greatest telescope-building, equation-wielding, code-writing physicists of our time. And they made her think . . . this science thing . . . it's pretty cool.