We must urgently revolutionise what we eat, how we grow it and the way we use land if the world is to combat dangerous climate change, according to the Intergovernmental Panel on Climate Change (IPCC) report published on Thursday.

Key points: Land sector produces around a quarter of global emissions

Land sector produces around a quarter of global emissions Diets need to move to low emissions sources

Diets need to move to low emissions sources Desertification will hit poorest and arid nations hardest

Transforming to clean energy, clean transport and industry alone will not cut global emissions enough to avoid dangerous warming beyond 1.5 degrees Celsius, the report authors warn.

Thursday's IPCC Special Report: Climate Change and Land builds on last year's dire warning from the panel on the consequences of 1.5C and 2C warming, which we're currently on track to reach by 2040 and the 2060s respectively.

"The stability of food supply is projected to decrease as the magnitude and frequency of extreme weather events that disrupt food chains increases," the report authors stated.

"At around 2C of global warming the risk from permafrost degradation and food supply instabilities are projected to be very high."

Shifting our farming practices presents an opportunity to cut emissions and improve health, the report states. ( Getty Images: Glow Images )

Improving land management, reforestation, and soil regeneration are essential steps in reducing emissions from the land sector, according to report co-author Annette Cowie from the University of New England.

"We really do need to take drastic action urgently to reduce greenhouse gas emissions," Professor Cowie said.

"When we plant trees, when we do sustainable land management practices that build organic land and soil, we actually take carbon out of the atmosphere and we store it in the land."

Emissions from the global food system, including peripheral activities like packaging and transport, are estimated to comprise between 21 per cent and 37 per cent of the world's human-generated greenhouse gas emissions, according to the report.

"About a quarter of the Earth's ice-free land area is subject to human-induced degradation," the authors state.

And changing the way we farm could improve things for ourselves, as well as for the planet: "Balanced diets featuring plant-based foods such as those based on coarse grains, legumes, fruits and vegetable, nuts and seeds and animal-sourced food produced in resilient, sustainable and low-greenhouse-gas-emission systems present major opportunities for adaptation and mitigation while generating significant co-benefits in terms of human health."

In Australia, where our meat consumption is particularly high on a global average, that means things like switching to low-emissions meat sources, ditching non-essential foods, and sourcing locally grown produce.

Reducing food waste is also identified as a key area to gain efficiency and reduce the environmental impact of agriculture.

Between 25 and 30 per cent of food is wasted worldwide, including crop waste, transport and store loss and personal waste.

"By 2050, reduced food loss and waste can free several million square kilometres of land," the authors write.

The report confirms the world has a double-edged sword hanging over its head, according to IPCC vice-chair Mark Howden.

"We ignore the interactions between climate change and the land at our peril."

Reforestation key to carbon reduction

Reforestation can help draw down carbon dioxide from the atmosphere. ( ABC Newcastle: Robert Virtue )

Systemic changes to agriculture to reverse soil erosion, rehabilitate degraded lands, minimise water and fertiliser use and increase carbon capture and storage are all identified as short- and long-term strategies for reducing greenhouse gases.

IPCC scientist Peter Newman from Curtin University said that while the energy sector has surged ahead in forging a path to low-to-no emissions, the land sector is dragging behind globally.

"Land has been a laggard because across the world there has been continued deforestation, which is fundamental to keeping carbon in the landscape," Professor Newman said.

"If you're cutting trees down more than you're planting, then that's not a great success story. And that has started to increase in recent years."

Deforestation in the Amazon has surged recently, but Australia's own deforestation rate has also climbed, drawing comparisons to Brazil.

"There was a lot of reforestation occurring right across Australia. It was certainly helped with the carbon tax because that was one way you could offset," Professor Newman said.

"[But] there's been an increase in deforestation, especially in Queensland, and that means we haven't been able to do nearly as well as the Federal Government has been saying."

One essential action that can immediately help reduce emissions, the report suggests, is protecting carbon-storing ecosystems such as forests, peatlands, rangelands and mangroves.

And rehabilitating these carbon-sink ecosystems can also achieve significant greenhouse-gas draw-down in the near future.

Recent research estimated that reforesting a billion hectares of degraded land globally could stall atmospheric carbon dioxide increase by around 20 years.

This could buy precious time while we continue to clean our energy, land-use, transport and industrial sectors, the researchers told the ABC earlier this year.

And there are dual benefits to reforesting and restoring ecosystems, according to Thursday's report.

They include increasing habitat for threatened species, reducing invasive species and improving human health.

Alleviating poverty and empowering women in developing nations are two strategies that could improve land management and slow population growth, said ecologist Hugh Possingham from the University of Queensland and the Nature Conservancy.

"If you improve women's education and give them autonomy over reproduction and their lives, birth rates drop and infant mortality drops," Professor Possingham said.

"Everything is win-win — you can't complain about women's education and you can't complain about children not dying."

Impacts will hit the poor and arid nations hardest

Desertification is expected to increase under climate change. ( Getty Images: Alexander Nicholson )

Under future climate change scenarios, droughts are predicted to become more intense and more common.

While this is the first IPCC report to have been produced with a majority (53 per cent) of authors from developing countries, it is developing nations that will likely feel the worst effects of food security, according to report co-author Priyadarshi Shukla.

"We will see different effects in different countries, but there will be more drastic impacts on low-income countries in Africa, Asia, Latin America and the Caribbean," he said.

Desertification in arid regions, including Australia, is expected to increase as tropical and subtropical climate zones expand poleward.

This is projected to put increasing pressure on already stretched agricultural sectors, driving up prices and threatening food security.

"Asia and Africa are projected to have the highest number of people vulnerable to increased desertification," the report says.

"The tropics and subtropics are projected to be most vulnerable to crop yield decline."

Already, the impacts of desertification are being felt due to land-use changes and climate change.

"The frequency and intensity of dust storms have increased over the last few decades due to land use and land-cover changes and climate-related factors," the report states.

"[Which is causing] increasing negative impacts on human health in regions such as the Arabian Peninsula and broader Middle East [and] Central Asia."

As well as educating and empowering women in developing nations, restoring indigenous land management practices can help rehabilitate land and curb emissions, according to the report.

"Agricultural practices that include indigenous and local knowledge can contribute to overcoming the combined challenges of climate change, food security, biodiversity conservation, and combating desertification and land degradation," the report states.

That position has the support of environment groups including the Nature Conservancy, according to country director Richard Gilmore.

"Give Aboriginal people the tools and resources to manage their land as they have done for thousands of years," he said.

"The Roman Empire was around 2,000 years ago, Aboriginal people have been managing the land here for 2,000 generations."