Delayed use of bioenergy crops might threaten climate and food security.
Nature
; 609(7926): 299-306, 2022 09.
Article
in En
| MEDLINE
| ID: mdl-36071193
ABSTRACT
The potential of mitigation actions to limit global warming within 2 °C (ref. 1) might rely on the abundant supply of biomass for large-scale bioenergy with carbon capture and storage (BECCS) that is assumed to scale up markedly in the future2-5. However, the detrimental effects of climate change on crop yields may reduce the capacity of BECCS and threaten food security6-8, thus creating an unrecognized positive feedback loop on global warming. We quantified the strength of this feedback by implementing the responses of crop yields to increases in growing-season temperature, atmospheric CO2 concentration and intensity of nitrogen (N) fertilization in a compact Earth system model9. Exceeding a threshold of climate change would cause transformative changes in social-ecological systems by jeopardizing climate stability and threatening food security. If global mitigation alongside large-scale BECCS is delayed to 2060 when global warming exceeds about 2.5 °C, then the yields of agricultural residues for BECCS would be too low to meet the Paris goal of 2 °C by 2200. This risk of failure is amplified by the sustained demand for food, leading to an expansion of cropland or intensification of N fertilization to compensate for climate-induced yield losses. Our findings thereby reinforce the urgency of early mitigation, preferably by 2040, to avoid irreversible climate change and serious food crises unless other negative-emission technologies become available in the near future to compensate for the reduced capacity of BECCS.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Crops, Agricultural
/
Agriculture
/
Global Warming
/
Food Security
Type of study:
Prognostic_studies
Limits:
Humans
Language:
En
Journal:
Nature
Year:
2022
Type:
Article
Affiliation country:
China