Putting the Brakes on Climate Change: Carbon Capture and Storage vs Enhanced Weathering
Abstract: Anthropogenic emissions of carbon dioxide (CO2), from fossil fuels and other industrial sources, are perhaps the biggest threat to the climate system yet many economies will remain reliant on these technologies for several decades. Reduction in CO2 emissions as well as active removal of CO2 are required in nearly all climate models that succeed in limiting global average temperature increase to less than 2°C above pre-industrial levels. Carbon capture and storage (CCS) and Enhanced Weathering (EW) are two technologies that, respectively, prevent CO2 emissions and remove CO2. Large scale deployment of both CCS and EW is nevertheless currently hampered by knowledge gaps including those related to environmental impacts, technological efficiency and public acceptability. In this talk, I describe recent and ongoing work that addresses these gaps. This includes the impacts of CO2 leakage from a sub-seafloor storage reservoir on sediment biogeochemistry and the benthic ecosystem based on results from the world’s first controlled sub-seafloor release of carbon dioxide, and novel large-scale field experiments to assess the efficacy of basalt fertilization of agroecosystems on CO2 and other greenhouse gas removal. The importance of communicating these experiments to local communities is also discussed.