The climate change policy challenge: Balancing the multiple roles of land use

Mike Rivington

Responding appropriately to climate change presents many complex challenges for policy makers and other stakeholders, especially when considering the use of land for mitigation and adaptation purposes. This because they represent additional burdens imposed on the biosphere on top of all the others. The capability and capacity of land to provide goods and services will also be affected by climate change impacts (e.g. changes in rainfall amounts and extremes (IPCC 2018a). These impacts will coincide with population growth and increasing demand for resources per capita. Further, the quality of available land has been and continues to be degraded. The recent Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services Global Assessment Report painted a stark picture of degradation of the worlds ecosystems and loss of biodiversity (IPBES 2019).

For climate change mitigation, afforestation and bio-energy crops are argued as having the potential to capture carbon and reduce the use of fossil fuels. This makes them an essential component of policies to achieve net zero emissions as they can offset emissions from sectors where it will be neither technically feasible nor economically viable to eliminate GHG emissions (van Vuuren et al 2011). Yet any plantation woodland expansion within the EU would need to be set against the substantial losses of old growth forests in the tropics. This creates an additional demand on land, adding to the developing conflicting requirements made on it at a time of the need for increasing food security.

Cutting through this complexity is the need for policy makers to understand “what are the required changes in balance between land uses needed in order to keep temperature rise below 1.5°C?”. This question has been explored in the Shared Socio-economic Pathways (SSPs) (Raihi et al 2017), and subsequent analysis of mitigation pathways (IPCC 2018b) to inform policy makers on opportunities for carbon dioxide removal. Figure 1 illustrates four alternative scenarios for the global land requirements for bioenergy with carbon capture and storage (BECCS) and afforestation and the consequent reduction in the area of other land uses.

Figure 1

Figure 1: Land use changes (M ha) in 2050 and 2100 (in relation to 2010) in four socio-economic pathways (S1, S2, S5 and a Low Energy Demand LED) that are consistent in potentially limiting temperature rise to 1.5°C (IPCC 2018b).

All these 1.5°C scenarios have a reduction in area for food production, most noticeably in pasture, though much less so for the Low Energy Demand scenario (LED) (Grubler et al 2018). The reduction in crop and pasture areas are to enable increases in energy crops and forests. Such substantial changes in land use have very large consequences on existing land-based economies (e.g. the livestock industry) and societies and thus present complex trade-off issues. Add to this that there are difficulties of carbon accounting for such land used (e.g. see Nexus Times “Why it is so difficult to measure biofuel emissions”) and for competing land uses means the need to adequately frame and conduct analysis in a way that does not seek to “simplify out” or ignore the complexity.

To identify potential solutions to this complex set of problems (development pathways that lead to sustainability) within a Social Metabolism Analytical framework, it is helpful to use three key benchmarks:

  • Is the solution Feasible? Can the development pathway be achieved within the limits of available resources? Does it respect ecological limitations such as water availability restrictions and the need to maintain soil health? Therefore, is it physically feasible? 
  • Is the solution Viable? We in the EU currently solve feasibility problems by externalising them, e.g. by using imports, but what are the consequences of this? Will externalisation remain feasible during the period of transition to a new and sustainable state?
  • Is it Desirable? Does the pathway resolve some issues but not others, or compound other problems and therefore risk not achieving sustainability? What does it do for aims such as the Sustainable Development Goals?

These questions identify dependencies (e.g. risk of externalisation) that whilst trying to resolve one problem cause another. For example, in 2009 the EU set targets in the transport sector for renewables and the de-carbonization of fuels that lead to substantial investment in biofuels (Valin et al. 2015), the production of which were outside of the EU. Hence the development of the biofuels industry has driven the expansion of cultivated land (e.g. causing deforestation). This has posed substantial issues in carbon and environmental impact accounting (see Nexus Times “Meeting EU biofuel targets: the devil is in the detail”).

The details above have created a picture of a land use and climate change complex ‘wicked’ problem. It is yet unclear what a feasible, viable and desirable pathway solution looks like. What is clear, though, is that conventional economics-based approaches to cost benefit analysis, with limited risk assessment, single scale accounting and trade-off analysis whilst considering ecological and entropy limits, are inadequate to deal with such complex problems. Within the context of a deteriorating environmental state, growing resource demand and climate change pressures, land is a key medium through which to consider the food-energy-water nexus using a MAGIC Social Metabolism Analysis approach.

References.

Grubler, A. et al., 2018: A low energy demand scenario for meeting the 1.5°C target and sustainable development goals without negative emission technologies. Nature Energy, 3(6), 515–527, https://www.nature.com/articles/s41560-018-0172-6

Harrison P. A., Hauck J., Austrheim G., Brotons L., Cantele M., Claudet J., Fürst C., Guisan A., Harmáčková Z.V., Lavorel S. et al. dans Rounsevell M., Fischer M., Torre-Marin Rando A., Mader A. (eds.) IPBES (2018): The IPBES regional assessment report on biodiversity and ecosystem services for Europe and Central Asia, Secretariat of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem services.

IPCC (20118a) Special report: Global Warming of 1.5°C. Summary for Policymakers.

IPBES (2018b) Rogelj, J., D. Shindell, K. Jiang, S. Fifita, P. Forster, V. Ginzburg, C. Handa, H. Kheshgi, S. Kobayashi, E. Kriegler, L. Mundaca, R. Séférian, and M.V. Vilariño, 2018: Mitigation Pathways Compatible with 1.5°C in the Context of Sustainable Development. In: Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [Masson Delmotte, V., P. Zhai, H.-O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. Zhou, M.I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, and T. Waterfield (eds.)].

IPBES (2019). Global assessment report on biodiversity and ecosystem services of the Intergovernmental Science- Policy Platform on Biodiversity and Ecosystem Services. E. S. Brondizio, J. Settele, S. Díaz, and H. T. Ngo (editors). IPBES Secretariat, Bonn, Germany.

Riahi K., D.P. vanVuuren, E. Kriegler, J. Edmonds, B.C. O’Neill, S. Fujimori, N. Bauer, K. Calvin, R. Dellink, O. Fricko, W. Lutz, A. Popp, J.C. Cuaresma, Samir KC, M. Leimbach, L. Jiang, T. Kram, S. Rao, M. Tavoni (2017) The Shared Socioeconomic Pathways and their energy, land use, and greenhouse gas emissions implications: An overview. Global Environmental Change 42, 153-168. http://dx.doi.org/10.1016/j.gloenvcha.2016.05.009 

Valin, H., Peters, D., van den Berg, M., Frank, S., Havlik, P.,Forsell, N. and Hamelinck, C. (2015) The land use change impact of biofuels consumed in the EU. Quantification of area and greenhouse gas impacts. https://ec.europa.eu/energy/sites/ener/files/documents/Final%20Report_GLOBIOM_publication.pdf

van Vuuren, D. P., Edmonds, J., Kainuma, M., Riahi, K., Thomson, A., Hibbard, K., Hurtt, G. C., Kram, T., Krey, V., Lamarque, J. F., Masui, T., Meinshausen, M., Nakicenovic, N., Smith, S. J., & Rose, S. K. (2011). The representative concentration pathways: An overview. Climatic Change. https://doi.org/10.1007/s10584-011-0148-z