Most of the global carbon emissions are used to support lifestyles of the world’s higher income population. An earlier blog post “Carbon inequality—the economic divide in greenhouse gas emissions” (https://understandclimate.com/?p=123) states: “The UN 2020 Emissions Gap Report presents a picture of worldwide carbon inequality… In 2015 the richest 1% of the world population emit 15% of the total carbon emission and about 83 tons/capita. While the poorest 50% emit 7% of the total emissions at about 1 ton/capita… [Also] the U.S. per capita emission is 3.4 times that of France, another advanced economy. The high U.S. emission is largely due to its citizens’ heavy reliance on cars, living in larger houses, and the amount of goods they consume.”
The U.S. annual per capita emission is about 16.5 tons. A study published in the Proceedings of the National Academy of Sciences (PNAS) reveals that in 2015, the highest U.S. income group (more than 200k annual income) has a per capita emission of 32.3 tons. This is about 2.6 times the per capita emission of 12.3 tons of the lowest income group (less than 15k annual income). This stark contrast points to lifestyles as having a significant impacts on climate change. Food, housing, and personal transport have the largest impact on climate change—representing about 4/5 of total lifestyle carbon footprints, compared to other areas like goods, leisure, and services.
As individuals, how do we modify our lifestyles in order to tackle climate change? The emission-reduction numbers below, based on the Cool Climate Network, show the tons of CO2-equivalent saved per year for each action.
Transportation:
Assuming driving 12,000 miles per year:
- Replacing a 25 mpg car with an electric car saves 4.4 tons of CO2 equivalent per year
- Replacing a 25 mpg car with a hybrid (55 mpg) saves 2.5 tons
- Replacing a 25 mpg car a fuel-efficient car (40 mpg) saves 2 tons
- Replacing driving (25 miles/week at 25 mpg) with bicycling saves 0.7 ton
- Taking public transportation instead of driving a 25 mpg car saves 0.5 ton
- Eliminating one cross-country round-trip flight per year saves 2.7 tons
Living space
The average U.S. home uses 3 to 4 times the electricity of a European one. That’s mostly due to inefficient appliances and lighting and insufficient insulation. Those are all things that home-owners can address. Assuming a household uses 10,700 kilowatt hours of electricity per year:
Assuming lights are on 5 hours per day:
- Replacing 10 incandescent lightbulbs with LEDs saves 0.7 tons
- Shutting five lights at 40 watts each for four hours per day saves 0.2 tons
Assuming a home is about 1,850 square feet, heated with electricity:
- Turning the thermostat up 5o F in summer saves 0.3 ton
- Turning the thermostat down 5° F in winter saves 0.3 ton
- Line drying two loads of laundry per week saves 0.2 ton
- Putting desktop computer in sleep mode nights and weekends and turn off monitor during those times saves 0.2 ton
- Installing low-flow showerheads saves 0.2 ton
Diet:
Agriculture is a major source of greenhouse gas emissions, and meat and dairy production are the big contributors. The biggest lever to cut food emissions is to stop food waste. UN estimates that the annual carbon footprint of global food waste is 4.4 gigatons of CO2 equivalent. Americans, specifically, waste about 25% of the food we buy. Even cutting back on animal products can make a difference. According to Project Drawdown, cutting five servings of meat a week saves 1 ton, adopting a vegetarian diet cuts emissions by about 63%, while going vegan can reduce by as much as 70%. (Please see my earlier post “How does our diet affect climate change?” https://understandclimate.com/?p=229)
Government policies needed:
Assuming that you belong to higher-middle income and your per capita emission is 30 tons per year (while the national average is 16.5 tons). Driving a hybrid car and adopting most of the above emission-reduction measures will reduce your emission by about 14 tons per year—reducing your emission by nearly 50%. But you are still more than 3 times the per capita emission of an average French citizen (at a per capita emission of 4.8 tons).
Individual behavior changes alone will not be enough to transition to a low-carbon society. Governments must establish policies to reduce “harmful” lifestyle options, for example, by heavily taxing high-carbon consumer habits like private jets, luxury yachts, excessive meat-consumption, and large homes; setting higher efficiency standards for automobiles and appliances; and providing generous funding for public transportation.