Britons should eat less beef and lamb and obtain more of their daily calories from vegetables to help to meet climate change targets, according to a government report.
Overall consumption of meat per person must fall by 40 per cent by 2050 if Britain is to emit only its “fair share” of global greenhouse gases.
The world can still “eat well, travel more and live in more comfortable homes” despite halving emissions and the population increasing from 7 to 10 billion by mid-century, according to the Department of Energy and Climate Change. It calculated the “global average lifestyle” consistent with preventing a dangerous rise in temperatures.
People in Britain would be able to live in slightly larger and warmer homes and own more televisions while adhering to the global average, but their diets and travel habits would need to be transformed. They would have to travel about 10 per cent fewer miles per year overall and a much larger share of their journeys would need to be by bus or bicycle compared with today’s car use.
The report says: “Switching from beef consumption, towards more poultry, pork, vegetables and grains can also significantly reduce the land required to produce food. Currently an area the size of a football pitch can be used to produce 250kg of beef, 1,000kg of poultry (both fed on grains and residues) or 15,000kg of fruit and vegetables.”
It says that if everyone switched to a daily diet of 160 calories of meat and a total of 2,100 calories, as recommended by the World Health Organisation for an “active and healthy lifestyle”, this would save 15 billion tonnes of carbon dioxide in 2050.
Land used for livestock production would be given over to growing trees to absorb CO2 and bioenergy would replace fossil fuels for burning.
A spokesman for the climate change department said: “UK meat consumption would have to fall by 360 calories today to 220 calories in 2050 if we were consuming our ‘fair share’.”
Consumption of beef and lamb would have to fall from 68 to 55 calories a day over the same period. Beef production would need to become more intensive, with the proportion of calves reared inside sheds rather than grazing in fields possibly more than doubling from 6 per cent to 15 per cent by 2050. Crop yields would need to rise by 40-60 per cent.
The department based its estimates on a “global calculator”, a computer-based modelling tool it developed with Imperial College London, the Met Office, China’s Energy Research Institute and several other scientific bodies.
The department said the tool, which is available from today on the internet, would allow governments, businesses and campaign groups “to consider the options for cutting carbon emissions and the trade-offs for energy and land use to 2050”.
To achieve the reduction in emissions, cars would have to become 50 per cent more efficient by 2050 and a third would need to powered by electricity or hydrogen. Up to half of homes globally would need to be heated “using electric or zero-carbon sources”.
Ed Davey, the energy and climate change secretary, said: “This global calculator shows that everyone in the world can prosper while limiting global temperature rises to 2°C, preventing the most serious impacts of climate change. Yet the calculator is also very clear that we must act now to change how we use and generate energy and how we use our land if we are going to achieve this green growth.”
Benny Peiser, director of the Global Warming Policy Foundation, a lobby group sceptical of climate change, said Mr Davey’s claim appeared to be based on optimistic assumptions that renewable energy would quickly become much cheaper.