Last month was the warmest July in almost 140 years since records began being compiled, NASA’s Goddard Institute for Space Studies. According to the agency, the average global temperature was almost one degree Celsius higher than the average for July between 1951 and 1980. Radio Sputnik discussed th...
CARBON CAPTURE AND STORAGE
SHAKY CASE FOR SPENDING ON NEGATIVE EMISSIONS
Negative emissions may sound like the latest descent into climate-speak, but they are fast becoming a much talked about concept in the climate and energy discussion. In the second half of this century, reabsorbing and storing more CO2 from the earth’s atmosphere than is created through industrial activity is increasingly referred to as a crucial weapon for successfully combating climate change. Tobias Nielsen at Lund university, Sweden, shares his thoughts on the topic
The main technologies for achieving negative emissions are planting new areas with forest, reforestation of previously wooded areas, bioenergy with carbon capture and storage (BECCS) and biochar. The technologies are needed primarily for two reasons.
First, some emissions are almost impossible to eliminate, such as those from agriculture and aviation. Paddy fields for rice cultivation and cows will continue to emit methane, while passenger aircraft are unlikely to run on electric power or hydrogen any time soon.
Second, proponents argue that negative emissions technology must be brought into play to compensate for the slow pace of conventional mitigation measures. Under the 2015 Paris climate agreement, countries aim to put in place pathways that can lead to so-called net-zero carbon emissions by 2050. In other words, carbon released during anthropological activity needs to be balanced by removing an equivalent volume of carbon from the earth’s atmosphere. Many national scenarios for reaching net-zero emissions and projections by the Intergovernmental Panel on Climate Change (IPCC) rely heavily on negative emission technologies.
Negative emissions is shorthand for the removal of carbon from the earth’s atmosphere, mainly through photosynthesis. In theory, the captured emissions are stored in plants on land, underground or absorbed in oceans. Achieving negative emissions has the potential to bridge the likely “emissions gap” to full decarbonisation should conventional mitigation efforts falter. The big question, however, is whether pursuing negative emissions will be a vital tool, or a dangerous distraction.