The free interactive Department for Energy and Climate Change (DECC) tool can be used by individuals and organisations to explore different options to reduce their greenhouse gas emissions.
One of its most significant illustrations is the extent to which high-meat diets are at odds with the drive to limit global temperature rises to the magic 2°C mark, beyond which the effects of climate will accelerate.
Insights from the calculator form the basis a DECC report that states that if the world cut its meat intake to the “healthy” level recommended by the World Health Organisation (160 calories of a daily 2,100 calories) it could save 15 gigatonnes of CO2 in 2050 – a third of all the CO2 emissions in 2011.
Prosperous Living for the World in 2050 also spells out the extent to which meat-eating contributes to destroying forests, which play an important role in storing carbon. Over the past decade almost 200 million hectares of virgin forests have been felled, partly to create grazing land and to grow feed crops, the report says.
Felling needs to stop and forest areas expand by 5-15 per cent by 2050 to absorb more carbon, it adds, something that – if current population and meat-eating trends continue – is incompatible with an expected rise of 45 per cent in global food demand.
Indeed, if forests are to be protected and expanded then smaller agricultural areas will need to yield 40-60 per cent more crops. Highlighting the bizarre and dangerous mathematics of meat-eating, the Global Calculator shows that on land the size of a football pitch, farmers can raise just 250 kg of beef – or grow 15,000 kg of fruit and vegetables.
Energy Secretary Ed Davey said the Global Calculator showed that it would be possible to limit global temperature rises to 2°C, but that it was “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”.
A report published last year by Chatham House, Livestock – Climate Change’s Forgotten Sector, disclosed how little the public were aware that meat-eating contributed to global warming. One of the authors of the independent policy institute’s report, Laura Wellesley, has called the Global Calculator “an invaluable means of broadcasting a message that has largely gone unheard. And with such powerful evidence, the need for urgent action on diets will be difficult to ignore.”