Finding pathways to national-scale land-sector sustainability
Achieving the 2030 UN Global Sustainable Development Goals at the national scale occurs only under very specific environmental and socio-economic pathways. New analyses are needed to support all nations in setting sustainability targets and implementing strategies for efficient target achievement across all sectors of society, environment, and the economy.
Picturesque, the above scene (courtesy of TH Digital Imaging) of the little coastal town of Edithburgh on the Yorke Peninsula in South Australia—near the farm where I grew up—is a zoomed-in illustration of the typical sustainability challenges resulting from the multiple demands on land including tourism, urban development, renewable energy from the Wattle Point wind farm, cropping and livestock production, and nature conservation.
In our Nature paper Finding pathways to national-scale land-sector sustainability, jointly led by Lei Gao and I, we aimed to assess whether it is possible to achieve the global Sustainable Development Goals (SDGs), or at least those relevant to land, at the national scale using Australia as a case study. We adapted and downscaled relevant sustainability targets at weak, moderate, and ambitious levels for economic development, food production, water resource use, renewable energy, greenhouse gas emissions abatement, and biodiversity/land degradation for 2030 and 2050. We projected potential land-use change under 648 pathways designed to cover a range of sustainability outcomes under plausible global and national socio-economic and environmental futures. We assessed the degree of target achievement under each of these pathways and quantified the option space—the specific environmental and socio-economic settings necessary at both global and national scales—for achieving multiple sustainability targets.
Lei and I. Quantitative land-use simulation is a compute-intensive job, with each 2050 pathway simulation taking between 20 and 40 hours. Luckily, we have access to big computers, very big computers. Plenty of data and models are available these days and the real challenge is to put it all together to answer complex questions about the future sustainability of the economy and the environment.
Why is this important?
On 1 January 2016 the nations of the world adopted the ambitious UN 2030 Sustainable Development Agenda including the 17 global goals. Crossing the spectrum of socio-economic and environmental aspects, many of the goals relate to land and how we use it including agriculture and food production, clean water, clean and affordable energy, conserving biodiversity and halting land degradation, and taking action on climate change.
Summary of the 17 global Sustainable Development Goals, many of which implicate and depend on land systems. Source: United Nations.
While the global goals and their associated targets are deliberately framed in general terms to achieve consensus amongst nations, achieving the global agenda will rely upon successful national-scale implementation. This needs specific and effective science-driven targets, tailored to specific national contexts, and supported by strong national governance.
Our study is the first to comprehensively downscale national targets and to quantify the future socio-economic and environmental conditions, or option space, in which targets relative to land and the environment can be achieved.
How did this research come about?
This paper was a classic case of right place, right time. Our research team had just developed a new land-use model called LUTO (Land-Use Trade-Offs) and completed a large land-use scenario modelling exercise in support of a multi-model integration exercise called the Australian National Outlook. The Outlook aimed to explore potential environmental, economic, and social futures for Australia and was published in Nature in 2015. We modelled 648 future scenarios for Australian land-use at really high spatial and temporal resolution. The dimensionality of the land-use scenarios cover a comprehensive range of global and national-scale environmental, economic, and policy settings for assessing the sustainability of land systems. These include climate change and emissions abatement, population and GDP, agricultural productivity changes, and bioenergy and biodiversity policies. And we had just published papers outlining the model and applying it, and testing its sensitivities. Importantly, this provided us with a terrific database about how land-use might change and the sustainability impacts of this change.
About the same time, the UN had signed the Agenda 2030 and published the Sustainable Development Goals (SDGs). This Agenda was just starting to become mainstream and it soon became clear that the SDGs would drive sustainability research for the foreseeable future. This had been followed by a number of high-level discussion pieces in Science and Nature about the complexity of achieving the SDGs. We had previously done a lot of work on complex social-ecological systems and the presence of trade-offs which limit the achievement of multiple targets in resource-constrained land systems. At the same time the Conference of the Parties climate change negotiation process in Paris agreement was clearly heading away from a global agreement towards nationally-determined targets. We realised that there was a need not just to do something significant and quantitative around SDG achievement, but that this must happen at the national scale where it can be supported by the stronger governance, policy, and institutions of individual nations. With our land-use scenarios in hand, we thought that we were well placed to do this work.
We wondered under how many of our future scenarios, or pathways, for Australian land systems the relevant SDGs could be achieved and what the characteristics of these pathways were. We suspected that it was very few due to the trade-offs we see all the time. We realised that we first needed to quantify and downscale the SDG targets for implementation in Australia. National-scale downscaling of the SDG had not been done anywhere. We wanted to downscale targets that were consistent with existing target-setting work to capitalise on this previous thinking and effort. We set targets for Australia then assessed levels of achievement under the 648 scenarios. Option spaces specified the specific combinations of future environmental, economic, and policy settings that multiple SDG targets may be achieved.
Senescing individual paddock trees isolated by increasingly industrial-scale agricultural production on Yorke Peninsula are emblematic of the threats facing native plant and animal species and the potential for conflict between biodiversity and food production—two key aspects of sustainability the land-sector must focus on (photo courtesy of TH Digital Imaging).
What we found...
The achievement of multiple SDGs is far from guaranteed, even when a suite of sustainability policies are implemented. In fact, they can be achieved only under very few, very specific environmental, socio-economic and policy settings at the global and national levels. This confirmed our original suspicions that there were very few pathways under which the SDGs could be achieved by a set of reasonable forward-looking policies and assumptions. Our title... 'Finding pathways...', reflects the scarcity of possible futures under which multiple targets can be achieved.
At this point, we knew we had something potentially very significant. The challenge was to clearly visualise and summarise this complex, highly-dimensional set of information. Our assessment spanned multiple targets, timelines, and levels of ambition, and how best to visualise and communicate that in a way that was digestible within the confines of a Nature letter was a substantial challenge. We trialled many different types of plots, tables, and maps before we came up with our target achievement figure and the parallel sets plots that occur in the paper.
Joint achievement of multiple targets was rare due to the trade-offs common in land systems such that if you change land-use and land management improve one thing (e.g. carbon storage), there is a good chance that you might make another worse (e.g. water availability).
As multiple targets are difficult to meet, hard choices are needed. We conclude that land contributions to sustainability must concentrate on those aspects where its role is without substitute such as producing food, conserving biodiversity and ecosystems, and halting land degradation. While land systems may also contribute to other targets such as emissions abatement, water, and energy by capitalising on co-benefits, these should only be secondary considerations—a bonus, rather than the main game. Land systems will require lots of help from other sectors such as clean energy, food systems, and water resource management to achieve multiple sustainability targets.
Nations require a new brand of scientific analyses to support national target-setting and evaluation for prioritising efficient and effective sustainability actions across society, the economy, and the environment.
Harvesting wheat on a family farm near Goldsmith's Beach on Yorke Peninsula. The wind farm in the background is an example of the strong State focus on renewable energy and represents a land-use not necessarily at-odds with agriculture, conservation, or other land-sector contributions to sustainability (photo courtesy of TH Digital Imaging).
Why are these findings significant?
The SDGs enshrine a set of global sustainability aspirations agreed to by all nations describing the future we all want, but our results suggest that they are very hard to achieve, at least those relevant to the land sector. Interventions are required right across the economy and environment, broadening and opening the systems in which sustainability is pursued, thereby reducing the constraints and the likelihood of trade-offs. A new brand of comprehensive and integrated scientific modelling and analysis is needed to underpin the setting of national targets and planning for their implementation. Without it, achievement of our shared global goals will be unlikely.
Where to from here?
Our results underscore the need for nations to undertake globally coordinated, national-scale, comprehensive, integrated, multi-sectoral analyses to support national target-setting and evaluation for prioritising efficient and effective sustainability interventions across society, economy, and environment.
We also recognise that this type of science does not yet exist and if we are to achieve our shared sustainability aspirations, governments and scientists need to work together to develop innovative solutions for sustainability. We hope that our conclusions around broadening the scope of land-sector sustainability implementation to include the broader economy and the environment can help nations set targets and plan for implementation of the Agenda 2030.
The paper in Nature is here: http://go.nature.com/2oBOBKI