The greatest impact individuals can have in fighting climate change is to have one fewer child, according to a new study that identifies the most effective ways people can cut their carbon emissions.
The next best actions are selling your car, avoiding long flights, and eating a vegetarian diet. These reduce emissions many times more than common green activities, such as recycling, using low energy light bulbs or drying washing on a line. However, the high impact actions are rarely mentioned in government advice and school textbooks, researchers found.
Carbon emissions must fall to two tonnes of CO2 per person by 2050 to avoid severe global warming, but in the US and Australia emissions are currently 16 tonnes per person and in the UK seven tonnes. “That’s obviously a really big change and we wanted to show that individuals have an opportunity to be a part of that,” said Kimberley Nicholas, at Lund University in Sweden and one of the research team.
The new study, published in Environmental Research Letters, sets out the impact of different actions on a comparable basis. By far the biggest ultimate impact is having one fewer child, which the researchers calculated equated to a reduction of 58 tonnes of CO2 for each year of a parent’s life.
The figure was calculated by totting up the emissions of the child and all their descendants, then dividing this total by the parent’s lifespan. Each parent was ascribed 50% of the child’s emissions, 25% of their grandchildren’s emissions and so on.
“We recognise these are deeply personal choices. But we can’t ignore the climate effect our lifestyle actually has,” said Nicholas. “It is our job as scientists to honestly report the data. Like a doctor who sees the…