Phys.org November 13, 2024
The scientifically recognized definition of Carbon Dioxide Removal requires removed atmospheric CO2 to be stored “durably”; however, it remains unclear what is meant by durably, and interpretations have varied from decades to millennia. An international team of researchers (Switzerland, USA – UC Berkeley) used a reduced-complexity climate model to examine the effect of Carbon Dioxide Removal with varying CO2 storage durations. They found that storage duration substantially affects whether net zero emissions achieve the desired temperature outcomes. With a typical 100-year storage duration, net zero CO2 emissions with 6 GtCO2 per year residual emissions would result in an additional warming of 1.1 °C by 2500 compared to permanent storage, thus putting the internationally agreed temperature limits at risk. Their findings suggested that a CO2 storage period of less than 1000 years is insufficient for neutralizing remaining fossil CO2 emissions under net zero emissions. According to the researchers their results reinforce the principle that credible neutralization claims using Carbon Dioxide Removal in a net zero framework require balancing emissions with removals of similar atmospheric residence time and storage reservoir, e.g., geological or biogenic… read more. Open Access TECHNICAL ARTICLE
Induced warming of net zero pulse CO2 emissions with different CDR storage durations. Credit: Communications Earth & Environment volume 5, Article number: 645, 11 November 2024