Rethinking Net-Zero systems, spaces, and societies: ?Hard? versus ?soft? alternatives for nature-based and engineered carbon removal

Carbon removal - also known as negative emissions technologies, or greenhouse gas removal - represents a core pillar of post-Paris climate policy, signaling for enhancing and constructing carbon sinks to balance emissions sources on route to ambitious temperature targets. We build on Amory Lovins' "hard" and "soft" alternatives for energy pathways to illuminate how foundational experts, technologists, and policy entrepreneurs think about different modes of resource inputs, infrastructure and livelihoods, and decision-making, regarding ten naturebased and engineered carbon removal approaches. Based on 90 original interviews, we show that hard and soft paths reflect different conceptions of systems, spaces, and societal involvement. We highlight that pathways depend on diverging concepts of economies-of-scale (capturing carbon at the largest possible scale, versus catalyzing systemic co-benefits) and carbon management (a waste product within conventional climate governance, versus diverse end-uses and values to be diversely governed). Our analysis further emphasizes two key uncertainties: whether renewables can be upscaled to allow synergies rather than tradeoffs between carbon removal and more widespread energy demands, and whether carbon certification can expand spatially to navigate long supply chains, and conceptually to incentivize diverse co-benefits. Experts remain motivated by antecedent concerns over land-use management and extractive industries, and that exploitative systems will - without guardrails - be replicated by inertia.