Engineering climate debt: temperature overshoot and peak-shaving as risky subprime mortgage lending

Abstract

Despite the ambitious temperature goal of the 2015 Paris Agreement, the pace of reducing global CO 2 emissions remains sluggish. This creates conditions in which the idea of temperature 'overshoot and peak-shaving' is emerging as a possible strategy to meet the Paris goal. An overshoot and peak-shaving scenario rests upon the 'temporary' use of speculative solar radiation management (SRM) technologies combined with large-scale carbon dioxide removal (CDR). Whilst some view optimistically the strategic interdependence between SRM and CDR, we argue that this strategy comes with a risk of escalating 'climate debt'. We explain our position using the logic of debt and the analogy of subprime mortgage lending. In overshoot and peak-shaving scenarios, the role of CDR and SRM is to compensate for delayed mitigation, placing the world in a double debt: 'emissions debt' and 'temperature debt'. Analogously, this can be understood as a combination of 'subprime mortgage' (i.e. large-scale CDR) and 'home-equity-line-of-credit' (i.e. temporary SRM). With this analogy, we draw some important lessons from the 2007-2009 US subprime mortgage crisis. The analogy signals that the efficacy of temporary SRM cannot be evaluated in isolation of the feasibility of large-scale CDR and that the failure of the overshoot promise will lead to prolonged peak-shaving, masking an ever-rising climate debt. Overshoot and peak-shaving scenarios should not be presented as a secured feasible investment, but rather as a high-risk speculation betting on insecure promises. Obscuring the riskiness of such scenarios is a precipitous step towards escalating a climate debt crisis. Key policy insights. The slow progress of mitigation increases the attraction of an 'overshoot and peakshaving' scenario which combines temporary SRM with large-scale CDR . Following the logic of debt, the role of CDR and SRM in this scenario is to compensate for delayed mitigation, creating a double debt of CO 2 emissions and global temperature . Using the analogy of subprime lending, this strategy can be seen as offering a combination of subprime mortgage and open-ended 'line-of-credit' . Because the 'success' of peak-shaving by temporary SRM hinges critically on the overshoot promise of large-scale CDR, SRM and CDR should not be discussed separately ARTICLE HISTORY

Boundary Work and Interpretations in the IPCC Review Process of the Role of Bioenergy With Carbon Capture and Storage (BECCS) in Limiting Global Warming to 1.5°C

“…This can be misinterpreted and have implications for governance and policy making since it risks legitimizing a more relaxed fossil decarbonization in the near term by building belief in speculative future CDR. This moral hazard, while not empirically verified, could obscure the critical need for increased ambition in the nearterm global response to climate change (Hilaire et al, 2019; see also Asayama and Hulme, 2019;Carton et al, 2020).…”

“…The critique has reached beyond the role of IAMs, and extends to the scope of the IPCC, its neutrality, scientific rigor, and integrity. Another strand of criticism focuses on the possibly performative, mitigationdeterring role of IAMs that depict net negative emissions as feasible through so called overshoot scenarios, where near-term emissions reductions are postponed or even canceled because they are perceived as costly (e.g., Geden, 2015;Markusson et al, 2018;Asayama and Hulme, 2019;Carton, 2019;Ellenbeck and Lilliestam, 2019;Workman et al, 2020).…”

Updated and outdated reservations about research into stratospheric aerosol injection

“…First, it is indefensible from the standpoint of intergenerational justice. Our generation (with generous contributions from immediately preceding generations) will likely bequeath to our descendants a substantially degraded environment and a breathtaking carbon "debt" which they will struggle mightily to repay (Asayama & Hulme, 2019). In such a context, is it justified for us to deprive future generations of tools that may lessen the pain we have inflicted?…”

Anticipatory governance of solar geoengineering: conflicting visions of the future and their links to governance proposals

“…Thus, in contrast to the ‘govern to enable’ rationale, this perspective views technocratic solutions with suspicion. Additionally, calls to consider solar geoengineering as a way to ‘peak-shave’ future temperature increases are critiqued, for example, as being a risky subprime mortgage approach to the climate challenge [ 81 ].…”

“…Concrete governance proposals relating to solar geoengineering focus on placing restrictions on research, development and future deployment. This includes calls to oppose solar geoengineering research [ 82 ] and demand legally binding international moratoria and prohibitions on outdoor research and deployment [ 80 , 81 , 82 , 83 , 84 ]. These latter commentators refer to a 2010 decision under the Convention on Biological Diversity (CBD) as a much-needed ‘de facto moratorium’ on solar geoengineering activities, and as an important and effective step in the right direction.…”