NZ Herald science writer Jamie Morton has followed up on the just-released UN report on climate change and reported on its big implications for agricultural New Zealand.

The Intergovernmental Panel on Climate Change (IPCC) – he writes – has released its wide-ranging special report, Climate Change and Land, after two years’ work.

Its key takeaways include:

• The temperature over land has risen considerably more than the global average, rising 1.53C since pre-industrial times compared with 0.87C globally.

• Farming, forestry and other land-use activities combined accounted for around a quarter of human-caused greenhouse gas emissions.

• Since 1961, the consumption of meat has more than doubled, while emissions of methane from cattle and manure had increased by 1.7 times in the same period.

The Summary for Policymakers of the Special Report on Climate Change and Land is available here.

A Fact Sheet and Headline Statements are available at www.ipcc.ch

NZ’s greenhouse gas emissions profile is here.

The international science journal, Nature,  says the IPCC report describes plant-based diets as a major opportunity for mitigating and adapting to climate change ― and includes a policy recommendation to reduce meat consumption.

“We don’t want to tell people what to eat,” says Hans-Otto Pörtner, an ecologist who co-chairs the IPCC’s working group on impacts, adaptation and vulnerability.

“But it would indeed be beneficial, for both climate and human health, if people in many rich countries consumed less meat, and if politics would create appropriate incentives to that effect.” 

The IPCC report says the race to limit global warming to 1.5 degrees above pre-industrial levels ― the goal of the international Paris climate agreement reached in 2015 ― might be a lost battle unless land is used in a more sustainable and climate-friendly way.

In his report for the NZ Herald, Mr Morton has recorded comment from:

• Associate Professor Anita Wreford, of Lincoln University, who said the report was highly relevant to New Zealand as it grappled for trade-offs with reducing emissions – around half of which were contributed by agriculture.

“The report highlights the importance of carefully designed policies that do not contradict each other or lead to unintended consequences, and careful planning and consideration of the long term in decision-making,” she said.

“Early action will be less costly than delaying action, and will generate opportunities to address wider issues beyond climate, including sustainable livelihoods, maintaining biodiversity, addressing societal inequalities and improving our health.

“However, the report emphasises that while better land management can help to tackle climate change, it cannot do it all – we still need steep greenhouse gas reductions across all sectors.”

• Climate scientist Professor Jim Salinger, who argued the agriculture sector could not ignore calls for maximum reductions in methane and nitrous oxide emissions, “as the international focus will now be on New Zealand’s response”.

“Both methane and nitrous oxide have increased, and the main culprit is livestock farming globally.”

The globally averaged atmospheric concentration of methane showed a steady increase between the mid-1980s and early 1990s, slower growth thereafter until 1999, a period of no growth between 1999-2006, followed by a resumption of growth in 2007.

Biological sources made up a larger proportion of emissions than they did before 2000, Salinger noted.   Ruminant animals like cows and sheep, and the expansion of

• Associate Professor Bronwyn Hayward, from the University of Canterbury, who called the report a “stark reminder” that everything we do affected our climate.

“For New Zealanders, one immediate and striking recommendation is to change our diets, traditionally high in meat and dairy to ones more balanced around more plant-based food choices that require less land and water to produce and involve the emission of fewer greenhouse gases,” she said.

“The report also notes the value of moving towards more sustainable, less intensive farming in the global north.”

Greenpeace responded to the IPCC report, describing it as the most comprehensive scientific assessment ever done on food, farming, land and climate change.

Greenpeace says the report should serve as the defining moment for this Government, a clarion call for immediate action to curb emissions from New Zealand’s biggest polluters, the dairy and agricultural industries.

“This report makes the science crystal clear. Industrial dairy and livestock farming are a major driver of the climate crisis,” says Greenpeace agricultural campaigner Gen Toop.

“If this Government is serious about climate action, it must halve the herd, ban synthetic nitrogen fertiliser and invest significantly in a shift to plant-based regenerative farming.”

The IPCC report found that agriculture, forestry and other types of land use now account for 23% of global greenhouse gas emissions. This is estimated to be up to as high as 37% of if the emissions associated with pre- and post-production activities in the food system are included

Increased ruminant livestock numbers and increased use of synthetic nitrogen fertiliser were found to be key drivers of these emissions, Greenpeace says.

Dairy cow numbers in NZ have nearly doubled since the 1990’s and the use of synthetic nitrogen fertiliser has increased 600%. The dairy industry is now emitting more climate pollution than NZ’s entire transport fleet.

Greenpeace is encouraging the public to submit on the Government’s “Action on agricultural emissions” consultation, which closes next Tuesday at 5pm, through a submission tool on its website.

The Nature report cites researchers who also note the relevance of the report to tropical rainforests, where concerns are mounting about accelerating rates of deforestation.

The Amazon rainforests is a huge carbon sink that acts to cool global temperature, but rates of deforestation are rising, in part due to the policies and actions of the government of Brazilian President Jair Bolsonaro.

Unstopped, deforestation could turn much of the remaining Amazon forests into a degraded type of desert, possibly releasing over 50 billion tonnes of carbon into the atmosphere in 30 to 50 years, says Carlos Nobre, a climate scientist at the University of São Paolo in Brazil. “That’s very worrying,” he says.

“Unfortunately, some countries don’t seem to understand the dire need of stopping deforestation in the tropics,” says Pörtner. “We cannot force any government to interfere. But we hope that our report will sufficiently influence public opinion to that effect.”

Nature says fossil fuel burning for energy generation and transport garners the most attention, but activities relating to land management, including agriculture and forestry, produce almost a quarter of heat-trapping gases.

In this country, the Government is proposing a Zero Carbon Act that would carry a split target – aiming to reduce all greenhouse gas emissions, aside from biogenic methane, to net zero by 2050.

Biogenic methane – the emissions created from livestock such as sheep and cattle – is not completely exempt as the bill commits to reducing it to 10 per cent below the 2017 levels by 2030.   

The Government is seeking public feedback on two recommendations on how the sector could ultimately be managed under the Emissions Trading Scheme.