New feed sources key to ambitious climate targets

• Published in: Carbon Balance and Management
• Main Authors: Walsh, B., Rydzak, F., Palazzo, A., Kraxner, F., Herrero, M., Schenk, P., Ciais, P., Janssens, I.A., Penuelas, J., Niederl-Schmidinger, A., Obersteiner, M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer 2015
• Subjects: Ocean acidification
• Online Access: https://pure.iiasa.ac.at/id/eprint/11321/; https://pure.iiasa.ac.at/id/eprint/11321/1/art%253A10.1186%252Fs13021-015-0040-7.pdf; https://doi.org/10.1186/s13021-015-0040-7

Net carbon sinks capable of avoiding dangerous perturbation of the climate system and preventing ocean acidification have been identified, but they are likely to be limited by resource constraints (Nature 463:747.756, [2010]). Land scarcity already creates tension between food security and bioenergy production, and this competition is likely to intensify as populations and the effects of climate change expand. Despite research into microalgae as a next-generation energy source, the land-sparing consequences of alternative souces of livestock feed have been overlooked. Here we use the FeliX model to quantify emissions pathways when microalgae is used as a feedstock to free up to 2 billion hectares of land currently used for pasture and feed crops. Forest plantations established on these areas can conceivaly meet 50 % of global primary energy demand, resulting in emissions mitigation from the energy and LULUC sectors of up to 544 +/- 107 PgC by2100. Further emissions reductions from carbon capture and sequestration (CCS) technology can reduce global atmospheric carbon concentrations close to preindustrial levels by the end of the present century. Though previously thought unattainable, carbon sinks and climate change mitigation of this magnitude are well within the bounds of technological feasibility.