The report seems to miss the critical role that land systems play in terms of feedbacks to the Earth System as a whole.

For example, there is credible evidence that a tipping point may exist for the Amazon rainforest, where a combination of direct human land-clearing and climate change - primarily through changing rainfall regimes - can trigger a rapid conversion of much of the forest to savanna or grassland ecosystems, thereby emitting large amounts of carbon to the atmosphere.

Yet there seems to be little attention given to such global-level feedbacks and abrupt shifts associated with land systems. 

Ominously, the report does mention the potential degradation of large areas of permafrost in the far north.

Valérie Masson-Delmotte, Co-Chair of IPCC Working Group I, noted that "there are very high risks related to permafrost degradation and food system instability that have been identified at 2°C of global warming".

Given that the 1.5°C Paris seems out of reach already, this warning adds to the concern that a global-level threshold or tipping point, consisting of interlinked feedback processes, could lie at temperature increases as low as 2°C above pre-industrial.

The latest IPCC Special Report on Climate Change and Land (Summary for Policy Makers) notes that human use directly affects more than 70 per cent of the global, ice-free land surface and that it provides the principal basis for our livelihoods.

Much of this comes from providing what we call ecosystem services, such as freshwater supply and food production.

As the global population grows, so the demand for freshwater and for food also grows and this accounts for much of the pressure to convert land to agriculture and forestry. 

But a growing population also needs land for housing, for jobs, schools and shops and this increasingly takes the form of large cities, which in turn often grow by converting agricultural land and areas of native vegetation on their fringes into urban areas.

Urbanisation and urban development contributes, therefore, to the problems of climate change not just in terms of land use change, but also by concentrating GHG emissions and creating increasingly deadly urban heat island effects.

The concentration of people in high-density settlements can also present serious challenges for adaptation as built environments are not especially flexible and adaptable.

Forms of urban growth that have been commonplace in Australia over the last century, involving low-density suburbs spreading outwards, consuming farmland and native vegetation and building-in car-dependency cannot make a significant contribution to any of the positive or optimistic pathways identified by the IPCC.

However, cities and urban areas also have the potential to contribute to mitigation strategies, but only if they are well managed and well designed.

Investment in appropriate green infrastructure in cities in the form of parks, urban forests and green roofs can make them healthier places, both physically and mentally, and well-designed buildings that generate their own energy, capture and use their own water and process their own waste can help reduce the carbon footprint of cities.  

This potential will only be realised through good planning and urban design which in turn must be built upon innovative forms of urban governance that tap into the creativity and desire to change among urban citizens.

Having recently completed the five-yearly Victorian 2018 State of the Environment Report (SoE), an independent scientific report on the environmental health of Victoria that includes extensive research and data on land use and agriculture, the IPCC’s Special Report Climate Change and Land (SRCCL) is timely.

Like SoE the SRCCL report highlights the growing pressures on the land-climate system.

Its findings add to the substantial body of scientific knowledge relating to climate change risk. The SRCCL report shows that while better land management can contribute to tackling climate change, it is not the only solution.

The SRCCL report also finds that policies outside the land and energy domains “can make a critical difference to tackling climate change”.

The findings around land use and climate change in this latest SRCCL report support the recommendation in the 2018 Victorian SoE that the path of reform guided by the UN Sustainable Development Goals (SDGs) is the correct one in the pursuit of ecologically sustainable development.

My job as Commissioner for Environmental Sustainability in Victoria, Australia is not just to review and report on the condition of Victoria’s environment, it is also to encourage decision-making that facilitates ecologically sustainable development.

The 2018 SoE report includes a Future Focus section that presents 20 recommendations that deal with specific and systemic issues, to support environmental improvements in Victoria to 2030.

Three recommendations relate specifically to improving the impacts of climate change on land and sustainable land management. They are:

1.    Improve regional climate projections
Regional climate projections at a finer spatial resolution, and more accurate rainfall projections, are required to improve management outcomes on land. Greater detail in climate projections can improve the proactive planning for many natural assets and sectors, including agriculture, with rainfall projections a particularly valuable tool for long-term policy development.

2.    Improve Victoria’s biodiversity outcomes on private land
Of the 35 biodiversity indicators in the SoE 2018 report, approximately half (18) are assessed as deteriorating in trend and approximately a quarter (9) have been assessed as “low performing”.[1] The lack of coordination of biodiversity and land data across agencies and an underinvestment in biodiversity science are critical issues impacting on biodiversity loss and impairing sustainable land management.

The rate of biodiversity loss on private land requires greater focus and effort by government. Victoria has nearly 23 million hectares of land: public land accounts for 37% and private land 63%. Private land conservation through permanent protection has been increasing across the state. However, it occurs at a slower rate than biodiversity loss and needs to be addressed as a priority over the next decade.

3.    Improve understanding of soil and land conditions and threats.
To manage Victoria’s land health during a time of climate change, improved coordination is required for the collection, consolidation, reporting and assessment of land data to drive statewide improvements in land-health condition across Victoria.

The main challenges to soil monitoring are the inherently high variability of soils (the changes are minor and occur over decades), and that measuring soil characteristics can be expensive. These are national issues.

New collaboration and funding models linking public and private databases and federated data could provide greater opportunity for soil-health monitoring.

Alignment of these new models with the work undertaken by the Cooperative Research Centre for High Performing Soils to develop and measure soil-health indicators for the future could be the foundation for a state soil and land condition monitoring program.

The SRCCL report comes just in time for the UN Climate Summit 2019 on September 23.

I’ve just read the Nature.com early news feed on reactions to the SRCCL and I thought it was significant that Nature.com repeated UN Climate Secretary António Guterres warning to delegates coming to this year’s Summit in New York: “I am telling leaders don’t come to the summit with beautiful speeches.”

This is a call to action. I hope that our recommendations to the Victorian Government will encourage and facilitate our progress to tackle the challenge of environmental degradation and climate risk.

Land is a critical resource, central to feeding the world, tackling climate change, ensuring human well-being and protecting nature. But the land is under pressure, and climate change is increasing that pressure.

Maintaining and improving the health of our land is vital.

Land and climate are interdependent: climate change exacerbates land degradation and diminishes carbon uptake by the land. Land degradation also reduces the resilience of human and natural systems to cope with climate change. 

On the other hand, the interconnections between land and climate also mean that controlling land degradation and enhancing land resources can deliver multiple benefits: climate change mitigation, climate change adaptation, food security, sustainable livelihoods and biodiversity conservation. 

Unsustainable agriculture, for food and fibre production, has been a major driver of climate change – but agriculture is also an important part of the solution

Holistic approaches are required to overcome the complex pressures driving unsustainable agriculture.

Measures to foster sustainable consumption, and reduce food loss and food waste, can further support sustainable food systems.

Agriculture, including deforestation, is responsible for about 1/5 of global GHG emissions.

But the land also takes up about 1/3 of emissions from the use of fossil fuels. And it can do more: when we plant trees and use sustainable land management practices that increase soil organic matter, we take carbon out of the atmosphere and store it in the land.

What’s more, this improves the productivity of the land, and its resilience to climate change. It also supports other ecosystem services and conservation of biodiversity.

I’m talking about using crop rotations, cover crops, strategically-placed perennial energy crops that can be used for renewable bioenergy, mixed cropping/grazing systems that use livestock to reduce the need for chemical fertilizers and herbicides, using biochar and biosolids as soil amendments that return nutrients and organic matter to the land, agroforestry. 

And we need to look across the food supply chain - another important aspect is tackling food loss and waste. There has been a lot of attention to this lately – currently, about 1/3 of food produced is lost or wasted – if we reduce that loss we free up land for energy crops and reforestation.

So the land can play an important role in meeting the challenge of climate change.

But it can’t do it all  - we urgently need a coordinated approach that reduces emissions in every sector.

We need to halt and reverse land degradation to maintain the capacity of the land to sequester carbon, and support food production.

We a mix of policy responses that create incentives for sustainable land management, such as the incentives under the Emissions Reduction Fund – now Carbon Solutions Fund – that allow landholders to earn carbon credits for storing carbon in vegetation and soil. 

This action is needed urgently – the longer we wait, the more land becomes degraded, the more carbon we put in the atmosphere, the harder it will be to meet the goal to limit global warming to less than 2 degrees, and to maintain the health of the land, and to feed the growing global population.

'Climate Change and Land' adds yet more urgency to the need to act on climate change, and shows how deeply both the causes and consequences of climate change are linked into our everyday lives and everyday behaviours. 
 
These messages are especially important for a dryland continent like Australia, where climate change is making it harder to manage our land to minimise emissions and maximise production, yet poor land management is contributing to the emissions that cause climate change.  
 
The report highlights how humans are pressing so many of the buttons that will contribute to compromising our global life support system. On the positive side, it highlights many places where quite modest actions could dramatically reduce the pressure on the land, whether in reducing food waste, shifting diets a little, better supporting our farmers to manage their land well, or avoiding water losses.  
 
In many of these, individuals can contribute usefully by changing levels of consumption, in ways that often also have personal health and financial co-benefits. It is in Australia’s profound interest to support global efforts to turn current trends around.

The new IPCC Special Report provides a thorough assessment of the interconnectiveness of climate change and land.

There are many deep insights, including the challenges of partly managing climate change, through land management while maintaining food security.

Given that the land is warming much faster than the climate as a whole, and with the observed increase in temperature extremes and heatwaves, the report re-enforces the need to deeply and dramatically cut greenhouse gas emissions, at the same time as urgently examining how Australia can protect the vital contribution of land in terms of settlements, water, food and biodiversity.

Climate change is rapidly ramping up existing threats to the land, reducing its ability to feed and support populations around the world and impacting on ecosystems.

At the same time, the land sector is currently contributing to climate change, even as it potentially offers some of the solutions to reducing greenhouse gases.

This report confirms the world has a double-edged sword hanging over its head.   

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

If left unchecked, the current situation threatens to make climate change worse, and leave the world hungry and with increasingly damaged ecosystems.”

[From ANU release: Professor Howden noted land use and the global food system produce 29 per cent of the world’s greenhouse gas (GHG) emissions. Land-based ecosystems also absorb 22 per cent of GHG emissions.]

“With the right management, there is potential to reduce the land sector’s GHG emissions and increase the land’s carbon sinks.

But the land sector alone cannot address climate change. Reducing our fossil fuel emissions remains absolutely vital.

Better land management not only delivers win-wins for farmers, communities, governments and biodiversity but also helps address climate change.

The IPCC’s latest report highlights yet again that climate change is not some distant future threat – it’s relevant to all of us now and it is in our own interests to address it urgently.

Improving our management of the land and tackling climate change the same time will bring multiple economic, health and environmental benefits.

The Special Report on Climate Change and Land synthesises and presents the key evidence relating to the interactions between land and climate. It represents an enormous body of literature and expertise from an international team of scientists, conducted over more than two years. It covers an extensive range of topics and issues around: how our activities on land affect the climate; how a changing climate is and will increasingly affect how we use the land, and; policy instruments and mechanisms to address these interactions.

It highlights that we rely on the land for food, energy, water, health and well-being, but it is already under pressure, and climate change will exacerbate these pressures.

The report is highly relevant for New Zealand as we grapple with the trade-offs involved with reducing greenhouse gas emissions, adapting to the impacts of climate change, managing the areas we value and maintaining and supporting our communities and societies in this process. The report puts these issues in the wider context of global climate and land.

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. 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.

This report will provide policy-makers with the synthesised evidence, and examples from around the world, of the implications of decisions they make regarding land and climate change. It is of critical relevance to New Zealand given the contribution of the land-based sector to our economy, as well as its dominance in our emissions profile.

The report is a sobering assessment of how much human activities have abused land resources with increased degradation and desertification, and a more recent greening trend, in good part reflecting the intensification of agriculture.

Those changes have led to decreased carbon stored in vegetation and soils, and increased methane (eg, from livestock) and nitrous oxide (eg, from fertilizers) emissions. Together, greenhouse gases emissions from the land have contributed to about one-quarter of all human-induced climate change. Remarkably, the global land has already warmed 1.5C above pre-industrial levels, 50 per cent higher temperature than the global warming (land and oceans). 

The results of the report are a clear call for a wholesale rethinking of the way we use and manage the land to ensure long term sustainable pathways for agricultural productivity, conservation, and an adequate use and restoration of the land to contribute to mitigate climate change.

A major aspect of this new report is to assess land-use strategies proposed to help reduce atmospheric carbon dioxide concentrations.

The findings are complex, but one key conclusion is that preventing desertification and deforestation around the globe would bring win-win benefits at low risk. Another is that there are limits to land-based carbon sequestration and biofuel production, especially since these tend to impinge on other land uses.

The detailed findings of this report will be important as the world tries to manage atmospheric carbon dioxide, and are particularly relevant for the Australian federal government’s plans to use land sequestration of carbon to help achieve Paris targets.