We need to talk about the most effective ways to reduce our carbon footprint

Current science textbooks and government documents about climate change are promoting relatively ineffective strategies for individuals to reduce their personal carbon footprint, according to an analysis published last week in Environmental Research Letters. Moreover, these sources mostly avoid discussion of the changes that would really make a difference in reducing emissions.

Today, the average person living in the United States is responsible for emissions of greenhouse gases equivalent to 16.4 tons of CO₂ every year. Per-capita annual emissions are equivalent to 16.3 tons of CO₂ in Australia, 13.5 tons in Canada, and 6.7 tons in the European Union. In order to keep the global average temperature increase under 2 °C, per capita annual emissions must fall to the equivalent of 2.1 tons CO₂ by 2050.

Seth Wynes and Kimberly A. Nicholas, of Lund University in Sweden, tallied up the emissions-reduction suggestions in Canadian science textbooks, as well as in government publications from Australia, Canada, the European Union, and the United States. These sources mostly emphasize low- and medium-impact actions that reduce a person’s carbon footprint by less than 0.8 tons of CO₂ per year, like hanging laundry to dry rather than using an electric clothes dryer, driving a more fuel-efficient vehicle, recycling, and replacing household light bulbs with more energy-efficient versions.

In contrast, when the researchers surveyed previously published literature to determine which actions make the greatest difference in reducing an individual’s carbon footprint, they found four high-impact strategies: eating a plant-based diet (saves 0.8 tons CO₂ per year), avoiding air travel (saves 1.6 tons CO₂ per round-trip transatlantic flight), living car-free (saves 2.4 tons CO₂ per year), and – the really big one – having one fewer child (saves 58.6 tons CO₂ per year).

The textbooks contain only 6 mentions of car-free living and 2 of avoiding air travel. Of the government documents, only the EU and Canadian guides suggest avoiding air travel, and only the Australian one mentions car-free living. None of the sources recommend having fewer children as a strategy to fight climate change.

But the new study has its own blind spots. One of them is the “have fewer children” strategy. It’s based on calculations from a 2009 study that assigned projected carbon emissions from future generations to people living now (a parent is responsible for half the lifetime emissions of each child, one quarter of the emissions of each grandchild, and so on – all divided over the years of the parent’s lifetime).

Those calculations make for some dramatic graphics. But “crediting” people today for emissions avoided many decades in the future is deeply misleading about how to achieve the massive near-term emissions cuts necessary to keep climate change in check. For example, if the average person in the United States is responsible for 16.4 tons of CO₂ emissions per year, the idea that having “one fewer child” saves 58.6 tons of CO₂ per year suggests that avoiding procreating yields negative carbon emissions to the tune of 42.2 tons of CO₂. This framing risks letting people with fewer children than average off the hook for their carbon emissions in the here and now.

A second misleading piece has to do with urban living. Although the researchers acknowledge that structural factors may affect people’s ability to make lifestyle changes, they frame their high-impact behaviors as choices largely within an individual’s control. For example, they write that going car-free has “the potential to contribute to systemic change” because it “reduces the need to build more roads and parking spaces, and supports higher-density urban design.”

This is backwards. With few exceptions, people don’t give up their cars and then demand greater urban density. They give up their cars when the availability of affordable housing in compact neighborhoods that are well served by public transit enables them to do so.

The researchers argue that in focusing on low-impact actions that are broadly palatable and relatively painless to achieve, textbooks and government publications risk trivializing the problem of climate change. That seems right. But the same is true of glossing over structural barriers to action – it makes reducing one’s personal carbon footprint seem easier than it actually is. We need to be honest about not just the behavioral changes that will make the biggest difference in reducing emissions, but about what it will take to get there.

Source: Wynes S and KA Nicholas. “The climate mitigation gap: education and government recommendations miss the most effective individual actions.” Environmental Research Letters. 2017.

Image: Ray Dumas via Flickr.