The UN Sustainable Development Solutions Network (UNSDSN) recently released an interim report on the "Pathways to Deep Decarbonization." This report acknowledges negative emissions might play a role in helping the world meet carbon emission goals, but came to the stance that:
"large-scale net negative emissions are still too uncertain to build into our country-level Deep Decarbonization Pathways (DDPs), even though we strongly support research programs that could make net negative emissions a future reality."
The UN is right that large-scale net negative emissions are quite uncertain. But I think the UN is overly pessimistic about the potential for negative emissions to contribute to sustainable decarbonization. The technology section on negative emission approaches in the report only includes two negative emission techniques:
"The popular placeholder for net negative emissions is the integration of biomass energy (BE) with CCS, both as technologies for electricity generation and biofuel production..."
"An alternative approach for net negative emissions would be the direct air capture of CO2 followed by geological storage."
Numerous other negative emission technologies have been proposed, many of which could also help the UNSDSN promote sustainable development across the world. For example, many holistic land management, afforestation, and biochar techniques could help improve agricultural productivity, water security, and ecosystem health in addition to removing carbon from atmosphere.
Holistic Ranch Management in Africa. Source: Savory Institute
Sustainable Palm Oil Plantation in Indonesia. Source: WWF
I hope that the UNSDSN reconsiders the role that CDR can play in meeting deep decarbonization and other sustainable development goals when it issues its final report in 2015.