 | | | | Links to recent scientific papers, web posts, upcoming events, job opportunities, podcasts, and event recordings, etc. on Carbon Dioxide Removal TechnologyHumans have depleted global terrestrial carbon stocks by a quarter (Source)Everything we publish on Carbon Removal Updates is free to access. If you value this work and are able, please consider supporting us as a paid subscriber. Your support sustains this vital work and helps us reach more people with balanced, timely information on this critical topic.
TABLE OF CONTENTSNote: Click on the headings listed in the table of contents above to easily navigate to the sections you're interested in. THIS WEEK’S TOP CDR HIGHLIGHTSREQUEST FOR PROPOSALS: Natural Resources Canada has issued request for proposals for a contractor to produce a Marine Carbon Dioxide Removal Regulatory Analysis Report. The study will assess technologies, environmental feasibility, and policy frameworks, with deliverables due by March 31, 2026. CALL FOR CONSULTATIONS: The German government is consulting on changes to the Carbon Dioxide Act that will introduces steps for advancing carbon storage in the country. RESEARCH PAPER: New research finds humans have depleted global terrestrial carbon stocks by 344 PgC - about a quarter (24%), driven by pasture expansion (30%), cropland expansion (24%), and forest management (23%). Dynamic vegetation models underestimate this deficit by 37% on average. Listen to the discussion of this study here, and find a short explainer here. NEW APP TO OFFSET CO2 EMISSIONS: Tao Climate has launched FlyGuiltFree.com, a global real-time carbon-removal platform for air travellers. The app lets passengers measure flight emissions and offset them instantly using hemp-based carbon removal, verified via AI, satellites, and science. NORTH AMERICA’S FIRST DAC STORAGE FACILITY: Deep Sky, Canada’s leading CDR developer, has launched operations at Deep Sky Alpha, marking the successful start of CDR and North America's first-ever sequestration of CO₂ captured directly from the atmosphere. The facility will test ten DAC technologies and aims to store up to 3,000 metric tons of CO₂ annually, equal to emissions from 700 cars. mCDR COALITION: A new Marine CDR Coalition has launched by the Carbon Business Council and World Ocean Council. The platform unites industry, nonprofits, and academics to advance responsible ocean carbon removal after two years of stakeholder dialogue. REPORT: International Air Transport Association (IATA), in collaboration with various other stakeholders across aviation and CDR, has developed a guide to the CDR market, providing a comprehensive overview of the CDR market and its interaction with the air transport industry. CALL FOR PROPOSALS: The US Department of Defense has an open call for proposals from US institutions that includes “Impacts of Aerosol Injection, Evolution, and Deposition on 3D Radiative Balance” (Office of Naval Research, Topic 17), with relevance to methane removal. Typical individual awards are up to $1.5 million per year for five years (supporting about 5–6 faculty-led teams) | White papers due September 03 | Full proposals due December 18. Read on to unpack more updates: COMMERCIAL NEWS Share Carbon Removal Updates RESEARCH PAPERSAuthors: Samira Rostom, Robert Symonds, Robin W. Hughes, Scott ChampagneSynopsis: This study explores integrating water electrolysis with biomass oxy-combustion and gasification for hydrogen production and CO₂ removal in BECCS systems. All cases achieve net-negative emissions, with pressurized gasification delivering the lowest hydrogen cost ($3.91/kg) and nearly double H₂ output. Combustion offers simpler, lower-cost designs but less efficiency. CO₂ credits ($117/t) can make LCOH cheaper than standalone electrolysis, with electrolyzer-supplied O₂ consistently outperforming ASU-based O₂.
Authors: Xin Hui Cheng, Yick Eu Chew, Jaya Prasanth Rajakal, Viknesh Andiappan, Bing Shen How, Raymond R. TanSynopsis: This study applies land use pinch analysis (LUPA) to evaluate negative emissions technologies (NETs) under land constraints. NETs like afforestation, soil carbon, biochar, DACCS, and BECCS can offset hard-to-abate emissions, but deployment depends on resource trade-offs. Five scenarios show DACCS offers the lowest land footprint (0–0.077 ha/tCO₂eq), outperforming biochar except in shared land use cases. LUPA proves useful for designing balanced, land-efficient CDR portfolios.
Authors: Maija J. Raudsepp; Sasha Wilson; Benjamin M. TutoloSynopsis: This study analyzes 854 water samples from British Columbia’s Central Plateau to define geochemical thresholds for Ca- and Mg-carbonate formation in the silicate–carbonate cycle. Results show maximum alkalinity thresholds of ~5 mEq/kg for Ca-carbonates and ~40 mEq/kg for Mg-carbonates across diverse water types. These insights help optimize geochemical CDR methods like enhanced rock weathering, where bicarbonate offers up to twice the CO₂ removal efficiency of carbonate minerals.
Authors: Grazia Leonzio and Nilay ShahbSynopsis: This study evaluates fully electrified DAC technologies using a hybrid learning curve to assess costs and environmental impacts across locations, seasons, and renewable energy sources. Among electrolysis, electrodialysis, electro-swing adsorption, and proton-coupled electron transfer (PCET), results show electro-swing and PCET offer lower costs and impacts, while electrolysis and electrodialysis are less efficient. A sustainability ranking finds PCET in China (2040–2050) powered by offshore wind as the most viable DAC pathway.
Authors: Raphael Ganzenmüller, Wolfgang A. Obermeier, Selma Bultan, Seth A. Spawn-Lee, Florian Zabel, Julia PongratzSynopsis: This study estimates the global terrestrial carbon deficit—the gap between actual and potential vegetation and soil carbon stocks—using semi-empirical data and machine learning. Results show a 344 PgC (24%) depletion, mainly from pasture (30%), cropland (24%), and forest management (23%). Dynamic global vegetation models underestimate this deficit by 37% on average, exposing key limitations. Findings improve understanding of anthropogenic ecosystem impacts and help refine climate models for nature-based solutions and mitigation policies.
Authors: Walker Raymond Lee, Douglas MacMartin & Amanda BorthSynopsis: This chapter asks whether anthropogenic climate change is “fixable” through climate intervention, focusing on CDR and solar radiation management (SRM). CDR directly offsets emissions but remains costly and immature at scale, while SRM could rapidly cool Earth by altering its energy balance but risks major unintended consequences for ecosystems and societies. Current trends point to 2–4 °C warming by 2100, far above Paris targets. Both approaches face technical, political, and ethical hurdles, requiring much more research and inclusive consultation before large-scale implementation.
Authors: Henry C. Henson, Isolde Callisto Puts, Mikael K. Sejr, Lise Lotte Sørensen & Johnna M. HoldingSynopsis: This study examines how Greenland Ice Sheet meltwater alters coastal carbon dynamics. Mixing experiments show freshwater dilution causes a nonlinear reduction in seawater pCO₂, confirmed by carbonate system modeling and long-term fjord data. Freshwater lowers buffering capacity, amplifying sensitivity to biogeochemical processes and acidification. Results reveal meltwater enhances biological control of pCO₂, reshaping Arctic coastal carbon cycling under accelerating ice loss.
Authors: Xinyu Jin, Shijian Jin, Lu Li, Roy G. Gordon, Pan Wang, Michael J. Aziz & Yunlong JiSynopsis: This study presents a hybrid phenazine flow cell for pH-swing DAC that overcomes oxygen sensitivity in redox-active organics. Using solid poly(phenazine sulfide) electrodes, the system separates reduced species from air, achieving stable CO₂ capture with high O₂ compatibility. It delivers 99% coulombic efficiency, with energy costs of 73 kJ/mol CO₂ (flue gas) and 104 kJ/mol CO₂ (DAC). This isolation strategy offers a promising route for efficient, oxygen-tolerant DAC and other electrochemical applications.
Authors: Dirk Paessler, Jens Hammes, Anna Anke Stöckel, Ralf Steffens, Ingrid SmetSynopsis: A 24-month greenhouse study with 67 rock–soil combinations assessed enhanced weathering impacts on carbon cycling using ~1M CO₂ efflux and 6,500 leachate measurements. Results showed three phases: strong disturbance effects early, variable first-year responses, and reduced treatment impacts in year two. Rock dusts often increased CO₂ efflux initially but effects faded. Alkalinity rises indicated some CDR, though inconsistent. High soil CO₂ fluxes vs leachate highlight the need for full carbon balance assessments.
Authors: Xuelong Zhuang, Jae Yeon Hwang, Mi Yeong Ko, Sung Woo Han, Edoardo Magnone, Jung Hoon ParkSynopsis: This study develops APTES-functionalized cerium oxide (CeO₂) adsorbents for direct air capture. Structural analyses confirmed that amine groups and oxygen vacancies were introduced, boosting CO₂ adsorption via synergistic interactions. CO₂-TPD tests showed higher capacity and strong cyclic stability under pure and 400 ppm CO₂, outperforming conventional amine adsorbents. Results highlight APTES–CeO₂ as a promising, efficient, and durable material for scalable DAC applications.
Authors: Tatjana Zurbriggen, Nicoletta Brazzola, Adrian Odenweller, Falko Ueckerdt, Joeri RogeljSynopsis: This study applies a probabilistic approach to assess DAC growth to 2050. Without strong intervention, DAC is likely to scale only to the megaton level, limiting its climate impact. However, with targeted policy support, particularly to accelerate near-term deployment, DAC could still reach gigaton-scale by mid-century, making it climate-relevant. Results highlight the critical role of policy in determining DAC’s contribution to net-zero goals.
Authors: Adnan I. Khdair, Ghaida A. Aburumman, Shayan Gholipour, Masoud AfrandSynopsis: This review explores advancements, challenges, and prospects for zero-carbon buildings and cities as a climate strategy. It highlights renewable energy, energy efficiency, and new materials, with emphasis on renovating existing buildings for greater carbon reduction. Key issues include standardizing methodologies, improving emission estimates, and applying real-time life cycle optimization. Intelligent technologies and infrastructures are also reviewed, outlining current progress, future directions, and emerging trends.
Authors: Xinyu Chen, Jinhai Leng, Fengying Ma, Jianqing Wu, Yi Jin, Fanglin He, Chao Yang, Haomin Huang, Xuquan Liu, Chongxiong Duan, Shanshan Shang, Daiqi YeSynopsis: This study develops hierarchically porous porphyrin-based MOFs (HP-PMOFs) with high-density defects and multi-scale porosity to overcome amine loading limitations in CO₂ capture. Functionalization with DETA, TEPA, and PEI significantly boosted DAC performance, with HP-PMOF–DETA achieving the highest uptake (1.40 mmol g⁻¹) and 84% regeneration efficiency after ten cycles at 400 ppm CO₂. Mechanistic analyses showed synergistic physisorption–chemisorption under dry conditions and water-facilitated bicarbonate formation under humidity. These findings highlight amine-functionalized HP-PMOFs as promising DAC adsorbents.
Authors: Fabio Correddu, Mondina Francesca Lunesu, Sara Sechi, Maria Francesca Caratzu, Giuseppe PulinaSynopsis: This study examines how emission metrics—GWP100 vs. GWP*, shape estimates of livestock methane’s warming impact and associated CDR needs. Using FAO projections to 2050, results show GWP100 can misrepresent methane’s cumulative effect, while GWP* better captures its dynamic temperature impact. Since metrics influence perceived mitigation effectiveness and CDR requirements, especially for methane-heavy sectors, careful metric selection is crucial for designing climate policies aligned with temperature goals.
Authors: Qianqian Wang, Jianhui Lv, Lijie Guo, Xiaodong ShenSynopsis: This study demonstrates enhanced CO₂ sequestration in ultramafic copper–nickel tailings using bisulfate activation and a two-stage carbonation process: slurry carbonation followed by secondary carbonation in backfilling materials (BFM). Forsterite and chrysotile showed the highest reactivity, achieving 13.46% CO₂ uptake after three days. Despite minor strength reduction, BFM met engineering standards while serving as a CO₂ sink. Stable carbonates were confirmed via XRD/SEM, and a new DTG-based method quantified efficiency. The approach couples mine backfilling with large-scale carbon mineralization, advancing sustainable mining and CDR.
Authors: Yuyang Chen, Binggen Zhan, Binglin Guo, Deyin Tian, Hongcen Li, Ping Ye, Huyong Qin, Peng Gao, Qijun YuSynopsis: This study investigates how biochar porosity influences CO₂ sequestration in cement composites under accelerated carbonation curing. Large-porosity biochar enhanced CO₂ transport, boosting inner-layer sequestration by 30.7% and reducing interlayer differences by 65.1%. However, excessive porosity lowered 28-day strength by 20.1%, while fine porosity hindered transport. Results show biochar regulates carbonation via pore structure, balancing carbon storage and strength in cement composites.
Authors: Malin Dufour &Kenneth MöllerstenSynopsis: This study analyzes the role of BECCS trade in achieving net-zero in the Nordics. Sweden has a surplus BECCS potential of ≥19 MtCO₂/yr, which could be transferred to countries with deficits, like Denmark and Iceland, under Article 6 of the Paris Agreement. Norway’s small potential likely meets its goals, while Finland will need domestic BECCS due to forest sink uncertainty. The authors recommend clear targets for reductions vs. removals, assessing national CDR balances, and fostering cross-border collaborations.
Authors: Jaeeun Sohng, Noah W. Sokol, Seth Whiteaker, Radomir Schmidt, Iris Holzer, et al.Synopsis: A 3-year field study in irrigated maize fields tested enhanced rock weathering (ERW) alone and with compost/biochar. Rock-alone raised pH, inorganic carbon, and boosted particulate and mineral-associated organic matter (POM, MAOM). However, combining rock with organic amendments lowered soil organic C and N compared to organics alone, though IC rose in rock+compost. Results show ERW can promote weathering and C storage but may slow organic C/N accrual, highlighting trade-offs for soil health and climate mitigation.
Authors: Yixiong Lu, Lei Jin, Junting Zhong, Xiaoye Zhang, Yanwu Zhang, Fanghua Wu, et al.Synopsis: A new SSP2-com scenario combining China’s 2060 net-zero pledge with late-century CDR deployment shows end-of-century warming limited to 1.87°C—below the Paris 2°C goal and cooler than SSP2-4.5 and SSP3-7.0 by 0.51°C and 1.47°C. Despite weaker carbon sinks, accelerated decarbonization in China avoids 0.08–0.29°C of warming. Results highlight that ambitious regional action plus global CDR can stabilize climate, though risks from uneven cooling and ecosystem feedbacks remain.
WEB POSTSTHESISAuthors: Bergero, CandelariaSynopsis: This dissertation examines the role of CDR in achieving net-zero emissions, focusing on aviation, U.S. environmental justice, and risks of failing to deliver carbon management. Using diverse datasets and models, it finds CDR is likely necessary but should remain secondary to emissions cuts. Results stress that achieving net-zero requires not only technological deployment but also careful attention to social, political, and economic justice to ensure feasible, fair climate action.
REPORTSAir transport sector market initiatives in CDR (IATA) UPCOMING EVENTSWe have curated a “Carbon Removal Events Calendar.” Explore and stay informed about upcoming events, conferences, and webinars on Carbon Dioxide Removal technology. Sync specific events / all events to your default calendar to ensure you never miss out on important CDR updates. Carbon Removal Events Calendar JOB OPPORTUNITIES"Cula builds the digital infrastructure for the global carbon removal industry. The Cula platform helps facilities run more efficiently, track operations in real time, and generate verifiable carbon removal certificates."
"Carbon Removal Canada is an independent non-profit accelerating the scale-up of carbon removal technologies by advocating for policy that enables responsible deployment, producing evidence-based research and analysis, and connecting the right people to the right information."
"Chestnut Carbon, a nature-based carbon removal developer, operates high-quality U.S. forestry projects that meet the most rigorous 3rd party verification criteria."
"Charm Industrial's technology converts excess biomass into carbon-rich bio-oil and injects it underground for permanent carbon removal."
"Varaha is a leading climate tech venture focused on nature-based solutions such as regenerative agriculture, ARR, and biochar projects that support smallholder land stewards at scale."
"This role is central to understanding and modeling the carbon sequestration capacity of different tree species, which will help inform and scale our sustainability initiatives."
"Vaulted is a waste management company that removes carbon. We take organic waste that can pollute our environment above ground and safely inject it ultra deep underground—permanently removing carbon from the atmosphere while protecting local land, air, and water."
"ClimateWorks Foundation is a nonprofit organization dedicated to ending the climate crisis by empowering philanthropy. It collaborates with funders, NGOs, and climate leaders worldwide to scale solutions in sectors such as renewable energy, sustainable transportation, and carbon removal."
"Lithos Carbon is an innovative early-stage carbon removal company and a leader in enhanced rock weathering technology."
"UNDO is tackling the greatest challenge of our time: climate change. We are a fast-growing for-profit business that is already one of the biggest carbon removal companies in the world."
"At neustark, we’re all in for one mission: permanently removing one million tons of CO2 in 2030, and even more every year beyond that."
"Silicate is a terrestrial enhanced weathering company accelerating a natural geological process—the weathering of minerals—to durably sequester atmospheric carbon dioxide and amend soil pH in farmland."
Looking for your dream job in CDR? There are 633 jobs available *right now*: check them all out at: CDRjobs Board
PODCASTSScoop School Lesson 2: Carbon Removal Leaders & Laggards | The CDR Policy Scoop | Scoop School Lesson 2: Carbon Removal Leaders & Laggards The CDR Policy Scoop 29:14 |
"The second lesson: Who’s leading and who’s lagging in carbon removal (CDR) policy?-Who’s getting it right, and who’s falling behind?-What works in CDR policy design?-Is it possible to replicate successes across borders?Yes, durable CDR policy is still in its early stages, but our in-depth looks at the UK, Switzerland, and Germany have proven there’s already a lot to discuss—and a lot others can learn from.Sebastian has been tracking these policy trends closely and will join Eve to unpack the best, the most ambitious, and the key lessons so far."
"This episode covers an article that discusses humanity's significant impact on global terrestrial carbon stocks, revealing a 24% depletion of natural vegetation and soil carbon, amounting to 344 PgC. It highlights that pasture and cropland expansion, along with forest management, are the primary drivers of this carbon deficit. The research also points out that current dynamic global vegetation models considerably underestimate this deficit by an average of 37%, emphasizing the need for more accurate modeling to assess anthropogenic impacts and inform climate mitigation strategies. The authors stress the importance of protecting pristine ecosystems and implementing effective conservation and restoration efforts to reverse these losses, given their comparability to cumulative fossil fuel emissions over the past five decades."
YOUTUBE VIDEOSDepleted Carbon Stocks | Explainer | Remove and Reflect Podcast "This is explainer of an article that discusses humanity's significant impact on global terrestrial carbon stocks, revealing a 24% depletion of natural vegetation and soil carbon, amounting to 344 PgC. It highlights that pasture and cropland expansion, along with forest management, are the primary drivers of this carbon deficit. The research also points out that current dynamic global vegetation models considerably underestimate this deficit by an average of 37%, emphasizing the need for more accurate modeling to assess anthropogenic impacts and inform climate mitigation strategies. The authors stress the importance of protecting pristine ecosystems and implementing effective conservation and restoration efforts to reverse these losses, given their comparability to cumulative fossil fuel emissions over the past five decades."
Oxford Symposium on the Carbon Removal Budget | OxfordSmithSchool - Playlist"The global net-zero transition necessitates the active integration of Carbon Dioxide Removal (CDR) strategies alongside emission reductions. However, with CDR emerging as a finite resource, a clearer understanding of its availability, equitable distribution, and potential applications is critical.This symposium focus on the Carbon Removal Budget (CRB) as a conceptual and practical tool to forecast, allocate, and manage the finite global potential of CDR in achieving and sustaining net-zero and net-negative emissions targets.This interdisciplinary gathering explore the theoretical underpinnings and practical implications of CRB, addressing the need to scale CDR technologies and integrate equitable principles for distribution across geographies, actors, and sectors."
The Weekly Challenger: The Community CDR Purchasing Challenge Meetup | OpenAir "A weekly meetup for anyone, anywhere interested in or already working on a Challenge campaign in their city, town or county. The agenda will include open discussion of matters related to execution, planning and lessons learned."
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