The Urgent Need for Carbon Dioxide Removal
Carbon dioxide removal, or CDR, has emerged as a key climate mitigation activity to limit global temperature increase to well below 2 degrees Celsius. In 2022, the rise in global temperature reached 1.1 degrees, resulting in more intense and frequent droughts, floods, and fires, as well as rising sea levels. Without immediate emission reductions, carbon dioxide removal, or both, society is currently on course to exhaust the remaining carbon budget to stay below a 1.5 degree rise within around 10 years at current levels of emissions from fossil-fuel combustion.
CDR technologies provide a critical opportunity to implement negative-emissions technologies to support the global transition toward renewable energy portfolios needed to reach net-zero carbon emissions. In “What Is the Big Picture in Carbon Removal Research?” (Issues, Fall 2022), Gyami Shrestha reviews the history and contemporary landscape of CDR research and observations supported by the US government. CDR emerges as an active area of interagency research, technological development, and implementation, now mapped by an extensive survey carried out by the Interagency CDR Research Coordination Group.
CDR technologies provide a critical opportunity to implement negative-emissions technologies to support the global transition toward renewable energy portfolios needed to reach net-zero carbon emissions.
Several thematic areas emerge from the survey that link the federal activities across areas of technology development, implementation, and monitoring. Technology areas include direct air capture and storage, soil carbon sequestration, reforestation and afforestation, enhanced mineralization, ocean capture and storage, and biomass removal and storage. Technology transfers to the private sector allow for scaling of activities such as direct air capture or mobilization of resources for climate-smart agriculture and forest management. And monitoring includes enabling new multiscale measurements of carbon dioxide from tower networks, aircraft, and spacecraft missions. Combined, the investments situate CDR as an important component of a climate mitigation strategy.
Several challenges remain. These include evaluating the full effects of CDR technologies on other ecological services that society depends on; implementing CDR while taking into account issues related to environmental justice; and addressing uncertainties and responsibilities for monitoring, reporting, and verification. These are multidisciplinary challenges that require expertise in Earth system science, social science, policy, land management, and engineering, and that need to be facilitated with continued coordination and transparency. Establishing unique partnerships between the public and private sectors can provide novel opportunities to rise to the challenge, as demonstrated recently through new satellite constellations successfully detecting point-source emissions of methane from oil, gas, agriculture, and landfills.
Benjamin Poulter
Research Scientist
Earth Sciences Division
NASA Goddard Space Flight Center
Gyami Shrestha reflects on her experiences during her tenure as director of the US Carbon Cycle Science Program, especially with respect to coordination of federal research on carbon dioxide removal (CDR) approaches and technologies. She describes how the program, along with the Interagency Carbon Dioxide Removal Research Coordination Group (I-CDR-C), produced a compendium of federal research activities in this arena. This compendium, as she notes, helps to “identify gaps and establish fruitful new collaborations and partnerships” among participating agencies, a crucial element for ensuring the success of federal CDR efforts.
While the breadth of the compendium is exciting, it is an incomplete snapshot of the full scope of federal CDR research efforts. Contributions to the compendium, and in fact participation in the I-CDR-C itself, are voluntary efforts by participants who have the time, energy, and commitment to engage with their colleagues on this topic. There are federal departments, agencies, and programs that fund or conduct relevant research but are not currently involved with I-CDR-C work, whether due to lack of awareness or limitations on capacity. Without a mandate for all relevant agencies and programs to report and coordinate, there will be missed opportunities and perhaps unforeseen consequences in this rapidly evolving arena.
Without a mandate for all relevant agencies and programs to report and coordinate, there will be missed opportunities and perhaps unforeseen consequences in this rapidly evolving arena.
As reported, the I-CDR-C found that some of the activities cited in the compendium were not explicitly focused on CDR, but instead were carbon cycle science research efforts that are foundational to the design and implementation of CDR work. As Shrestha notes, there are “fundamental questions [about the carbon cycle] that have yet to be sufficiently answered.” Inclusion of these research activities in the compendium demonstrates an understanding of the importance of this underlying research to CDR, but there needs to be clearer articulation of pathways to support and enhance the connections of research to operations and back again. How can programs that are typically considered more “basic” science ensure that their insights inform applications like CDR? How can CDR activities potentially contribute to our fundamental knowledge of the carbon cycle and other Earth and social sciences?
Ongoing interagency collaboration through the I-CDR-C can help facilitate these matters, as can engagement with the broader research community. Programs such as the North American Carbon Program and the US Ocean Carbon and Biogeochemistry Program provide space for the ongoing development and support of communities of practice around carbon dioxide removal that span sectors and domains, and both programs have held trainings and workshops on the topic that have generated significant enthusiasm. The urgency and complexity of climate change threats requires collaborative, iterative, adaptive approaches to research and applications that not only cross traditional disciplinary boundaries but will likely also require new organizational and institutional frameworks in the way we approach science altogether.
Libby Larson
Coordinator
North American Carbon Program