A radical form of “offsetting” carbon dioxide emissions to prevent climate change is proposed today – having fewer children. Each new UK citizen less means a lifetime carbon dioxide saving of nearly 750 tonnes, a climate impact equivalent to 620 return flights between London and New York*, the Optimum Population Trust says in a new report. Based on a “social cost” of carbon dioxide of $85 a tonne**, the report estimates the climate cost of each new Briton over their lifetime at roughly £30,000. The lifetime emission costs of the extra 10 million people projected for the UK by 2074...