This week’s publication highlights cover a range of issues such as life cycle assessment within the context of land-based CDR, impact of CO2 removal on european near surface wind speed, approaches to and difficulties inherent in marine carbon dioxide removal, enhancement of terrestrial and marine carbon sinks and data on removals from scenarios and pathways within long-term national climate strategies.
Life Cycle Assessment in the Monitoring, Reporting, and Verification of Land-Based Carbon Dioxide Removal: Gaps and Opportunities
Abstract
Life cycle assessment (LCA) has been widely used to evaluate the carbon negativity and environmental impacts of carbon dioxide removal (CDR) pathways. Various monitoring, reporting, and verification (MRV) protocols have been developed to assess the carbon credits of CDR projects within voluntary and compliant carbon markets. Many MRV protocols incorporate life cycle thinking, LCA methods, and data. This perspective examined recent LCA studies and MRV protocols published by main carbon registries, focusing on four critical land-based CDR methods: bioenergy combined with carbon capture and storage, biochar, enhanced rock weathering, and afforestation and reforestation. We compared the carbon accounting and environmental impact assessment methods employed in these LCA studies and MRV protocols to identify their methodological similarities and differences. Our analysis reveals that the LCA community can support MRV protocols by providing critical insights into baselines, additionality, uncertainty, multifunctionality, environmental safeguards, holistic emission factors, and overlooked carbon pools. We recommend that future LCA research prioritize timing, permanence, scaling, and dynamic modeling for CDR. Addressing co-benefit and land use change impact assessment will further benefit both LCA and MRV development. Collaboration between the LCA and CDR communities is essential for developing robust frameworks to support carbon markets and policy making.
Yao, Y. and Zhang, B. (2025) Life Cycle Assessment in the Monitoring, Reporting, and Verification of Land-Based Carbon Dioxide Removal: Gaps and Opportunities. Environmental Science & Technology
Read the full paper here: Life Cycle Assessment in the Monitoring, Reporting, and Verification of Land-Based Carbon Dioxide Removal: Gaps and Opportunities I Environmental Science & Technology.
Asymmetric Response of European Near Surface Wind Speed to CO2 Removal
Abstract
Understanding the changes in near-surface wind speed (NSWS) is crucial for weather extremes and wind energy management. This study examines the response of NSWS to atmospheric carbon dioxide (CO2) removal using large ensemble simulations and the Carbon Dioxide Removal Model Intercomparison Project models. Our results indicate that increasing CO2 levels lead to an overall reduction in the Northern Hemisphere (NH) extratropical NSWS over land. Subsequent CO2 reduction during the early ramp-down period rapidly restores NH NSWS. However, this recovery stalls and enters a declining trend during the late ramp-down period, mainly due to opposite negative NSWS trends in Europe. Notably, the rapid recovery of simultaneous Atlantic Meridional Overturning Circulation (AMOC) counteracts the recovery of North Atlantic air meridional temperature gradient and the westerly jet by global cooling, therefore prolonging NH mid-latitudes NSWS weakening. Our findings underscore the pivotal role of AMOC in modulating NSWS under varying CO2 concentrations and provides insights for future climate adaptation.
Li, Z. et al. (2025) Asymmetric Response of European Near Surface Wind Speed to CO2 Removal. EGU Sphere
Read the full paper here: Asymmetric Response of European Near Surface Wind Speed to CO2 Removal I EGU Sphere
Perspectives and Challenges of Marine Carbon Dioxide Removal
Abstract
The Paris Agreement to limit global warming to well below 2°C requires drastic reductions in greenhouse gas emissions and the balancing of any remaining emissions by carbon dioxide removal (CDR). Due to uncertainties about the potential and durability of many land-based approaches to deliver sufficient CDR, marine CDR options are receiving more and more interest. We present the current state of knowledge regarding the potentials, risks, side effects as well as challenges associated with technical feasibility, governance, monitoring, reporting and accounting of marine CDR, covering a range of biotic and geochemical approaches. We specifically discuss to what extent a comparison with direct injection of CO2 into seawater, which had been proposed decades ago and is now prohibited by international agreements, may provide guidance for evaluating some of the biotic marine CDR approaches.
Oschlies, A. et al. (2025) Perspectives and Challenges of Marine Carbon Dioxide Removal. Frontiers Climate
Read the full paper here: Perspectives and Challenges of Marine Carbon Dioxide Removal I Frontiers Climate
CMIP6 Models agree on similar carbon cycle feedbacks between enhancing terrestrial and marine carbon sinks
Abstract
Carbon dioxide removal (CDR) is a crucial component of climate mitigation required to reach international climate targets. However, gaps exist in our understanding of the responses and feedbacks of the Earth system to the deployment of CDR. In this study, we compare two complementary approaches that enhance the terrestrial and marine carbon sinks with afforestation and reforestation (A/R) and ocean alkalinity enhancement (OAE), respectively, under the high emission scenario SSP5-8.5. Eight CMIP6 Earth system models are utilized, enabling a quantification of both inter-model and internal variability. By mid-century, simulated large-scale deployment of A/R and OAE individually reduces atmospheric CO2 concentrations by up to 20 ppm. For both methods, while carbon removal from the atmosphere is robust, it is difficult to detect the effects on global mean temperature, posing challenges for monitoring, reporting and verification of mitigation efforts. To quantify the carbon cycle feedbacks, we define the carbon cycle feedback ratio of A/R (OAE) as the ratio of changes in the marine (terrestrial) sink to changes in the terrestrial (marine) sink. We show that the carbon cycle feedback ratios of A/R and OAE have similar magnitudes, which is -16% and -13%, respectively. Moreover, although inter-model differences of the simulated amounts of carbon removal due to A/R are large, the corresponding carbon cycle feedback ratios of A/R are similar.
Wey, H. et al. (2025) CMIP6 Models agree on similar carbon cycle feedbacks between enhancing terrestrial and marine carbon sinks. Environmental Research Letters.
Read the full paper here: CMIP6 Models Agree on Similar Carbon Cycle Feedbacks between Enhancing Terrestrial and Marine Carbon Sinks I Environmental Research Letters.
A dataset of emissions and removals from scenarios and pathways within long-term national climate strategies – the LTS-SP dataset
Abstract
Long-term low emission development strategies (LT-LEDS), supported by Article 4, paragraph 19, of the Paris Agreement, present scenarios and pathways aligned with national long-term climate targets. There is a growing interest in understanding whether the collective effort of national climate plans align with the goals of the Paris Agreement, alongside the feasibility, sectoral focus, and the balance of emissions and removals seen in national scenarios. Here we introduce the long-term strategy scenarios and pathways (LTS-SP) dataset, a dataset presenting scenarios and pathways detailed within LT-LEDS or similar long-term strategies. We detail the level of total and sectoral greenhouse gas emissions in 2050, or the year in which net zero is achieved, alongside the emissions and removals from land-use, land-use change, and forestry (LULUCF) and removals from engineered carbon dioxide removal (CDR) methods. We provide a comprehensive overview of our procedure and compare our dataset with current published estimates. We end by summarising several caveats to our dataset, detailing the limitations of LT-LEDS, and their use in climate policy research.
Smith, H. et al. (2025) A dataset of emissions and removals from scenarios and pathways within long-term national climate strategies – the LTS-SP dataset. 485 (12) Scientific Data.
Read the full paper here: A dataset of emissions and removals from scenarios and pathways within long-term national climate strategies – the LTS-SP dataset I Scientific Data.