Climate target for agriculture

Flickr.com / Adam Cohn CC-BY--NC-ND

A new study proposes that the agricultural sector needs to reduce emissions by 1 billion tonnes of CO₂e per year by 2030 to contribute to the 2°C target.

119 states have included mitigation of agricultural emissions in their Intended Nationally Determined Contributions (INDCs) submitted to the UNFCCC. However, little is known about how these reductions will be accomplished.

Scientists from the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) and the International Institute for Applied Systems Analysis (IIASA) used three different integrated assessment models to find that agriculture must reduce non-CO₂ emissions by 0.92–1.37 GtCO₂e a year by 2030. This is what is needed in order to contribute to a “likely” (66%) chance of staying within the 2°C warming limit. It was suggested that 1 GtCO₂e may be an appropriate preliminary target. This is approximately 4–5 per cent of the 26 GtCO₂e reductions a year needed across all sectors to achieve the 2°C target.

The researchers also found that established methods fall short of reaching this goal. Technical improvements in livestock management, cropland management and rice-paddy management can contribute to reductions of up to 0.40 GtCO₂e annually in 2030. While structural transformations, such as transforming extensive rangeland systems to more efficient livestock systems, can reduce emissions by 0.21 GtCO₂e annually in 2030.  

“This research is a reality check,” commented Lini Wollenberg, leader of the CCAFS Low Emissions Development research programme, who led the study. “Countries want to take action on agriculture, but the options currently on offer won’t make the dent in emissions needed to meet the global targets agreed to in Paris. We need a much bigger menu of technical and policy solutions, with major investment to bring them to scale.”

The study discusses several options for how this gap could be bridged. Many high-tech solutions they believe will take too long to introduce, especially in developing countries. A more feasible way forward would be to introduce new breeds of cattle that emit less methane, together with wheat and corn varieties that inhibit production of nitrous oxide, since this would not require extensive changes in management.

The researchers also highlight the need for additional targets for agricultural emissions. In the absence of models they suggest some aspirational targets based on what is assumed to be achievable globally at low costs by 2030:

• Soil carbon sequestration could roughly mitigate emissions by 1.2 GtCO₂e, using a carbon price of US$ 20 per tonne;
• reducing land-use change due to clearing for agriculture could reduce emissions by 1.71–4.31 GtCO2e using the same carbon price;
• decreasing food loss and waste by 15per cent, could lead to emission reductions of 0.79–2.00 GtCO2e;
• and shifting dietary patterns to WHO recommendations or in response to increased carbon prices would mitigate 0.31–1.37 GtCO2e.

These estimates add up to a more comprehensive goal for agriculture-related emissions in the order of 5–9 GtCO₂e a year, which corresponds to about 19–35 per cent of all mitigation efforts needed across all sectors.  

The researchers highlight the importance of developing this approach to match top-down sectorial mitigation demands with the bottom-up mitigation potentials and the corresponding policies at a global scale. In their final conclusions they write “without the guidance of 2°C-based goal in agriculture, much effort will be driven by what is technically or politically feasible, rather than by what is necessary”.

Kajsa Pira

IIASA ress release, 17 May 2016 http://www.iiasa.ac.at/web/home/about/news/160517-ag-climate.html

“Reducing emissions from agriculture to meet the 2°C target”, Global Change Biology http://onlinelibrary.wiley.com/doi/10.1111/gcb.13340/abstract;jsessionid...