If one in five people in richer countries went near-vegan, and threw away a third less food than they currently do, while poor countries were assisted to preserve their forests and restore degraded land, the world’s agricultural systems could be absorbing carbon dioxide by 2050 instead of adding massively to global heating as they do at present.
Tree-planting and improving the fertility of soil through better farming practices would also be needed, according to a study of global forests, farming and food systems published in the journal Nature Climate Change.
Managing agricultural and other land in a more environmentally sound manner could take the world nearly a third of the way towards meeting the Paris agreement goals. “These [measures] are feasible now and deliver many other benefits,” said Stephanie Roe, environmental scientist at the University of Virginia and lead author of the paper.
“Recent reports on the state of our forests and food systems show a worrying lack of progress in the land sector, and our window of opportunity to deliver on the Paris agreement is getting smaller. However, I remain optimistic because we have all the tools we need, as well as increasing public pressure and political will to turn things around.”
The changes would also allow for healthier diets globally, improve livelihoods in poor areas, preserve wildlife and flora, and make for higher water and air quality. Many of the measures suggested, such as cutting food waste and shifting from excessive meat consumption, would also save money. For example, improving soil management through organic farming practices would cost about $57bn (£43.9bn) but save nearly $2tn over the period, according to one estimate used in the study.
Land accounts for about 25% of global greenhouse gas emissions, or 11 gigatons of carbon dioxide a year. With the right measures, according to the study, it would act instead as a carbon sink absorbing 3 gigatons from the atmosphere a year by 2050. That could give some scope for other sectors such as aviation to continue to use limited amounts of fossil fuels while staying within the global carbon budget needed to avoid a temperature rise of more than 1.5C (a rise of 2.7F) above pre-industrial levels.
The authors set out a roadmap for the six large-scale measures they propose, including: reducing deforestation, peatland burning and mangrove destruction by 70%; restoring forests, peatlands and coastal mangroves to generate enough carbon dioxide saving to cancel out China’s annual emissions; planting trees to save as much carbon dioxide as that emitted by the EU.
Improving farming practices, including moving to more organic practices, would mean better soil management that could cut carbon dioxide equal to India’s annual emissions. Consumer food waste in rich countries and big developing countries could be cut by a third, while the losses from food production in poor regions such as sub-Saharan Africa and south-east Asia could be cut drastically through simple measures such as more refrigeration and better transport. Moving a fifth of people to plant-based diets in developed and emerging countries, particularly the US, the EU, China, Brazil, Argentina and Russia, is seen as possible by 2030. These near-vegan diets would involve consuming less than 2,500 calories a day and no more than 60g of animal protein.
(January 1, 1959)
The physicist Edward Teller tells the American Petroleum Institute (API) a 10% increase in CO2 will be sufficient to melt the icecap and submerge New York. “I think that this chemical contamination is more serious than most people tend to believe.”
(January 1, 1965)
Lyndon Johnson’s President’s Science Advisory Committee states that “pollutants have altered on a global scale the carbon dioxide content of the air”, with effects that “could be deleterious from the point of view of human beings”. Summarising the findings, the head of the API warned the industry: “Time is running out.”
(January 2, 1970)
Shell and BP begin funding scientific research in Britain this decade to examine climate impacts from greenhouse gases.
(January 1, 1977)
A recently filed lawsuit claims Exxon scientists told management in 1977 there was an “overwhelming” consensus that fossil fuels were responsible for atmospheric carbon dioxide increases.
(January 1, 1981)
An internal Exxon memo warns “it is distinctly possible” that CO2 emissions from the company’s 50-year plan “will later produce effects which will indeed be catastrophic (at least for a substantial fraction of the Earth’s population)”.
(January 1, 1988)
The Nasa scientist James Hansen testifies to the US Senate that “the greenhouse effect has been detected, and it is changing our climate now”. In the US presidential campaign, George Bush Sr says: “Those who think we are powerless to do anything about the greenhouse effect forget about the White House effect … As president, I intend to do something about it.”
(January 2, 1988)
A confidential report prepared for Shell’s environmental conservation committee finds CO2 could raise temperatures by 1C to 2C over the next 40 years with changes that may be “the greatest in recorded history”. It urges rapid action by the energy industry. “By the time the global warming becomes detectable it could be too late to take effective countermeasures to reduce the effects or even stabilise the situation,” it states.
(January 1, 1989)
Exxon, Shell, BP and other fossil fuel companies establish the Global Climate Coalition (GCC), a lobbying group that challenges the science on global warming and delays action to reduce emissions.
(January 1, 1990)
Exxon funds two researchers, Dr Fred Seitz and Dr Fred Singer, who dispute the mainstream consensus on climate science. Seitz and Singer were previously paid by the tobacco industry and questioned the hazards of smoking. Singer, who has denied being on the payroll of the tobacco or energy industry, has said his financial relationships do not influence his research.
(January 1, 1991)
Shell’s public information film Climate of Concern acknowledges there is a “possibility of change faster than at any time since the end of the ice age, change too fast, perhaps, for life to adapt without severe dislocation”.
(January 1, 1992)
At the Rio Earth summit, countries sign up to the world’s first international agreement to stabilise greenhouse gases and prevent dangerous manmade interference with the climate system. This establishes the UN framework convention on climate change. Bush Sr says: “The US fully intends to be the pre-eminent world leader in protecting the global environment.”
(January 1, 1997)
Two month’s before the Kyoto climate conference, Mobil (later merged with Exxon) takes out an ad in The New York Times titled Reset the Alarm, which says: “Let’s face it: the science of climate change is too uncertain to mandate a plan of action that could plunge economies into turmoil.”
(January 1, 1998)
The US refuses to ratify the Kyoto protocol after intense opposition from oil companies and the GCC.
(January 1, 2009)
The US senator Jim Inhofe, whose main donors are in the oil and gas industry, leads the “Climategate” misinformation attack on scientists on the opening day of the crucial UN climate conference in Copenhagen, which ends in disarray.
(January 1, 2013)
A study by Richard Heede, published in the journal Climatic Change, reveals 90 companies are responsible for producing two-thirds of the carbon that has entered the atmosphere since the start of the industrial age in the mid-18th century.
(January 1, 2016)
The API removes a claim on its website that the human contribution to climate change is “uncertain”, after an outcry.
(January 1, 2017)
Exxon, Chevron and BP each donate at least $500,000 for the inauguration of Donald Trump as president.
(January 1, 2019)
Mohammed Barkindo, secretary general of Opec, which represents Saudi Arabia, Kuwait, Algeria, Iran and several other oil states, says climate campaigners are the biggest threat to the industry and claims they are misleading the public with unscientific warnings about global warming.
Prof Thomas Crowther, founder of the Crowther Lab, who was not involved with the study, said: “This is an excellent review of the many carbon drawdown solutions that the land can provide. There are immense benefits of restoring natural ecosystems like forests, wetlands and peatlands. Managed ecosystems can also be critical through effective agroforestry, biochar techniques and regenerative agriculture that can increase soil carbon sequestration. The review also reveals the considerable uncertainty and challenges that we face in realising this carbon drawdown potential, highlighting the need for more quantitative research into the scale and dynamics of carbon storage on land.”
Developing nations are hoping that the forthcoming UN meeting on the climate emergency, COP25 in Santiago, will encourage rich countries to focus on helping them cut emissions through better land use and management of the oceans. A spokesperson for the UK’s Department for International Development said: “Cutting carbon emissions by helping developing countries change how they use and farm land is a priority for UK aid. We are fighting illegal deforestation and supporting poor farmers to make their practices greener. By making farming practices more efficient, we reduce the amount of land needed to produce food.”
Nancy Harris of the World Resources Institute, a co-author of the study, said: “The longer we delay action to protect forests, the more difficult it will be to achieve the Paris agreement targets and the more we will need to rely on unproven negative emission technologies.”