November 5, 2020

expert reaction to study of Food System Emissions and Climate Change Targets

A study published in Science looks at the effect of food production emissions on our ability to achieve climate change targets.

Prof Pete Smith FRS, Professor of Soils & Global Change at the University of Aberdeen, said:

“This is not the first study to show that dietary change away from meat and dairy is needed to hit 1.5 or 2°C targets.  What this study shows nicely, though, is the contribution of different diets to Paris targets – and that even if fossil fuel emissions were immediately stopped, our current food system would push us past these targets.

“The study shows that plant-rich diets need to widely adopted, in addition to efficiency improvement and reduced waste. Importantly, if we are to hit the 1.5°C target, we need to have widespread adoption of all food system transitions (diet, production, waste reduction). In addition to a complete transition away from fossil fuels in the coming decades, we will also need dramatic food system transformation.”

Prof Dominic Moran, Professor of Agricultural and Resource Economics, Roslin Institute, University of Edinburgh, said:

“This is good research, mostly sensible projections and calculations of the mitigation potential of various demand-side measures to reduce food-related emissions (compared to a baseline of business as usual).  Getting a lot of these implemented to the necessary extent will be tricky.

“It tells us that food emissions will generally rise with population and livestock intensification to meet a meat transition in middle income countries.  It tells us that food emissions will rise relative to the share from other emitting sectors, which are more tightly regulated.

“This relative share story has been pointed out by others including the UK committee on Climate Change.  Others – me included – have pointed out that food and agriculture emissions are going under the regulatory radar (e.g. no emissions pricing) because governments are loath to wade into this sector and are still trying to coax rather than beat with a stick.  Spoiler alert: it’s not working (fast enough) with either producers or consumers.   We probably need to face up to the fact that emissions taxes need to extend to this sector and there needs to be a public debate about whom might be classed as a ‘polluter’ – the producer and/or the consumer. 

“The overall message is that governments cannot wish this problem away, and while dictating what we put in our mouths is tricky, sooner or later they will have to face up to the fact that it’s necessary if we want to meet targets.  It also has health co-benefits.”

Dr Joeri Rogelj, Director of Research and Lecturer in Climate Change and the Environment, Grantham Institute, Imperial College London, said:

“The paper elaborates in more detail what the IPCC Special Report on Global Warming of 1.5°C already highlighted in 2018: deep emissions reductions are required in all sectors for limiting warming to 1.5°C. No sector is off the hook. A steep decline of global CO2 emissions to net zero by mid-century needs to be accompanied by deep reductions in non-CO2 greenhouse gases such as methane and nitrous oxide. The planet has warmed by 1.2°C since the start of the industrial revolution – so we are very close to 1.5°C and future emissions of each and every sector will therefore have a strong impact on where we end up in terms of global warming.

“The overall findings of this study are therefore not very new, but the study’s look at how changes in food production can contribute to reductions in future non-CO2 greenhouse gases is informative and shows the challenges ahead.”

Prof Dave Reay, Professor of Carbon Management, University of Edinburgh, said:

‘We are quite literally eating our way through the last scraps of a Paris-compliant global carbon budget. The business-as-usual scenario described here – of ballooning emissions from the global food system – is not new. What is new are the stark numbers on just how effective changes, such as plant-rich diets, reduced waste and improved efficiency, could be in delivering on the Paris climate goals.

“The assumption is usually that food emissions will dominate our impact on the climate long after we’ve decarbonised global energy; that the so-called ‘unavoidable emissions’ from what we eat will require industrial-scale capture and storage to balance them. In fact, this study shows that the global food system has the potential to hit or even exceed net zero emissions by the end of the century.

“Ahead of the COP26 climate conference in Glasgow next year, many nations (including the UK) are preparing to announce their updated national commitments to tackle climate change. Our food, and rapid action to make it both low carbon and climate resilient, should be their bread and plant-based butter.”

‘Global food system emissions could preclude achieving the 1.5° and 2°C climate change targets’ by Michael A. Clark et al. was published in Science at 7pm UK TIME on Thursday 5 November 2020.

Declared interests

Prof Moran: “No interests.”

Prof Reay: “No interests.”

No others received.