A study by Lund University researchers in the journal Environmental Research Letters has identified four of the most effective actions individuals can take to reduce greenhouse gas emissions.
We recognize these are deeply personal choices. But we can’t ignore the climate effect our lifestyle actually has.
The authors of the study, Kimberly Nicholas and Seth Wynes, examined 39 peer-reviewed papers, carbon calculators and government reports, and analyzed a range of individual lifestyle choices and their potential impact on the reduction of greenhouse gas emissions. The findings revealed that four lifestyle choices have a higher impact than others. These include: eating a plant-based diet, avoiding air travel, living car-free, and having smaller families.
Each of these four actions was determined to be high impact because each reduces greenhouse gas emissions by at least 0.8 tons of CO2-equivalent per year per individual. The study also identified these actions to be “best in class” compared to others because they have the potential to contribute to systemic change: for example, if more people lived car-free, there would be less of a need to build roads and parking lots. The researchers applied a life-cycle analysis to the actions to assess the emissions released from cradle-to-grave, taking into account factors like production, transportation, storage, packaging, etc.
“There are so many factors that affect the climate impact of personal choices, but bringing all these studies side-by-side gives us confidence we’ve identified actions that make a big difference,” said Wynes in Science Daily. “Those of us who want to step forward on climate need to know how our actions can have the greatest possible impact. This research is about helping people make more informed choices.”
An important part of the study also included examining the actions and interventions recommended to reduce an individual’s carbon footprint in government reports in the EU, USA, Canada and Australia, as well as 10 Canadian high school textbooks.
High school textbooks were examined because the researchers identified adolescents as an important target group due to their potential to adopt life-long habits and influence behavior in the households they live in. Five textbooks recommended living car-free, only two suggested avoiding air travel, and none advocated eating a plant-based diet or having one child less.
As for the advice published in government reports, these were judged to be insufficient to tackle the Paris Agreement goal of keeping the global average temperature increase under 2° C.
Oft-cited recommendations included replacing standard light bulbs with energy-efficient ones, recycling and buying energy-efficient products but these practices only result in a low to moderate impact. The study concluded that government recommendations tend to focus on “incremental changes with a much smaller potential to reduce emissions,” and none of the reports examined mention any of the four high-impact actions identified by the study.
The study has determined that eating a plant-based diet (defined as entirely meat-free) is four times more effective than recycling while changing household light bulbs to energy-saving ones is eight times less effective.
The study points out that a reduction of 2.1 tons of CO2 per person per year is required to meet the Paris agreement’s 2° C climate target by 2050. Here are a few examples of the amount of CO2 saved per action:
- Replacing light bulbs: less than 0.2 tons saved per individual per year
- Eating plant-based: 0.8 tons saved per individual per year
- Avoiding air travel: 1.6 tons saved per round-trip transatlantic flight
- Living car free: 2.4 tons per individual per year
- Having one child less: an average for developed countries of 58.6 tons per year
“We recognize these are deeply personal choices. But we can’t ignore the climate effect our lifestyle actually has,” said Nicholas in Science Daily. “Personally, I’ve found it really positive to make many of these changes. It’s especially important for young people establishing lifelong patterns to be aware which choices have the biggest impact. We hope this information sparks discussion and empowers individuals.”