• Energy Research

AbstractThe IPCC Special Report on 1.5 °C concluded that anthropogenic global warming is determined by cumulative anthropogenic CO2emissions and the non-CO2radiative forcing level in the decades prior to peak warming. We quantify this using CO2-forcing-equivalent (CO2-fe) emissions. We produce an observationally constrained estimate of the Transient Climate Response to cumulative carbon Emissions (TCRE), giving a 90% confidence interval of 0.26–0.78 °C/TtCO2, implying a remaining total CO2-fe budget from 2020 to 1.5 °C of 350–1040 GtCO2-fe, where non-CO2forcing changes take up 50 to 300 GtCO2-fe. Using a central non-CO2forcing estimate, the remaining CO2budgets are 640, 545, 455 GtCO2for a 33, 50 or 66% chance of limiting warming to 1.5 °C. We discuss the impact of GMST revisions and the contribution of non-CO2mitigation to remaining budgets, determining that reporting budgets in CO2-fe for alternative definitions of GMST, displaying CO2and non-CO2contributions using a two-dimensional presentation, offers the most transparent approach.

This package generates all of the model runs and plotting code for "Current infrastructure does not yet commit us to 1.5°C warming". See enclosed README file for dependencies and how to run.

Abstract The vast majority of agri-food climate-based sustainability analyses use global warming potential (GWP100) as an impact assessment, usually in isolation; however, in recent years, discussions have criticised the ‘across-the-board’ application of GWP100 in Life Cycle Assessments (LCAs), particularly of food systems which generate large amounts of methane (CH4) and considered whether reporting additional and/or alternative metrics may be more applicable to certain circumstances or research questions (e.g. Global Temperature Change Potential (GTP)). This paper reports a largescale sensitivity analysis using a pasture-based beef production system (a high producer of CH4 emissions) as an exemplar to compare various climatatic impact assessments: CO2-equivalents using GWP100 and GTP100, and ‘CO2-warming-equivalents’ using ‘GWP Star’, or GWP*. The inventory for this system was compiled using data from the UK Research and Innovation National Capability, the North Wyke Farm Platform, in Devon, SW England. LCAs can have an important bearing on: (i) policymakers’ decisions; (ii) farmer management decisions; (iii) consumers’ purchasing habits; and (iv) wider perceptions of whether certain activities can be considered ‘sustainable’ or not; it is, therefore, the responsibility of LCA practitioners and scientists to ensure that subjective decisions are tested as robustly as possible through appropriate sensitivity and uncertainty analyses. We demonstrate herein that the choice of climate impact assessment has dramatic effects on interpretation, with GWP100 and GTP100 producing substantially different results due to their different treatments of CH4 in the context of carbon dioxide (CO2) equivalents. Given its dynamic nature and previously proven strong correspondence with climate models, out of the three assessments covered, GWP* provides the most complete coverage of the temporal evolution of temperature change for different greenhouse gas emissions. We extend previous discussions on the limitations of static emission metrics and encourage LCA practitioners to consider due care and attention where additional information or dynamic approaches may prove superior, scientifically speaking, particularly in cases of decision support.

Abstract Energy policy faces a triple challenge: increasing resilience and guaranteeing the security of supply of both fossil and non-fossil energy, minimising the impact on consumer energy prices, and retaining consistency with Paris Agreement climate goals. High prices and producer rents, however, also present an opportunity: to open a conversation about applying the principle of extended producer responsibility (EPR) to fossil fuels. We demonstrate that this could deconflict energy security and climate policy at an affordable cost by stopping fossil fuels from causing further global warming. Implementing EPR through a combination of geological CO2 storage and nature-based solutions can deliver net zero at comparable or lower costs than conventional scenarios driven with a global carbon price and subject to constraints on CO2 storage deployment. It would also mean that the principal beneficiary of high fossil fuel prices, the fossil fuel industry itself, plays its part in addressing the climate challenge while reducing the risk of asset stranding.

No description supplied

Bastin et al . (Reports, 5 July 2019, p. 76) claim that global tree restoration is the most effective climate change solution to date, with a reported carbon storage potential of 205 gigatonnes of carbon. However, this estimate and its implications for climate mitigation are inconsistent with the dynamics of the global carbon cycle and its response to anthropogenic carbon dioxide emissions.