“Limiting global warming to 2 or even 1.5 degrees Celsius is partly linked to the question of whether excess CO2 can be removed from the atmosphere, for example through biomass plantations and Carbon Capture and Storage," explains Vera Heck, lead author of the study. “But how would this massive interference with our biosphere affect other ecological boundaries of the planet? This is what we investigated in this comprehensive study. With the result that CO2 emissions can only be balanced by biomass and Carbon Capture and Storage (CCS) with extensive environmental damage for other planetary boundaries. If, on the other hand, these ecological guidelines were consistently taken into account, the potential for biomass and CCS is very small".
The concept of planetary boundaries encompasses key processes and systems that determine the stability and resilience of the Earth's system and thus shape the environmental conditions that are the foundation of our society today. Some of these boundaries have already been transgressed. “To ensure a safe operating space for mankind, the challenge is to respond to planetary boundaries in context. Protective measures in one area can have negative consequences for another – this is what our study shows very clearly using the example of negative emissions as a possible measure for climate protection. More and more, the very important analysis of the climate problem has to be reflected with the Earth System as a whole in mind”, stresses Wolfgang Lucht, co-author and PIK expert for Earth System Analysis.
“Our work substantiates that it would be highly risky to play only this card as a strategy for achieving the climate targets," adds Dieter Gerten, head of the PIK research group on Planetary Boundaries. “We need a swift shift to sustainable management in agriculture and water use as well, to limit pressure for the global environment. To achieve climate targets in this bigger context, it is therefore essential to reduce CO2 emissions right now, instead of relying on supposedly green technologies that are supposed to make up for a slower pace".
Article: Vera Heck, Dieter Gerten, Wolfgang Lucht, Alexander Popp (2017): Biomass-based negative emissions difficult to reconcile with planetary boundaries. Nature Climate Change. [DOI: 10.1038/s41558-017-0064-y]
Weblink to the article: http://dx.doi.org/10.1038/s41558-017-0064-y
