CO₂-removal News

Elkhlifi et al. (2023): Potential Role of Biochar on Capturing Soil Nutrients, Carbon Sequestration and Managing Environmental Challenges: A Review

Zouhair Elkhlifi, Jerosha Iftikhar, Mohammad Sarraf, Baber Ali, Muhammad Hamzah Saleem, Irshad Ibranshahib, Mozart Daltro Bispo, Lucas Meili, Sezai Ercisli, Ehlinaz Torun Kayabasi, Naser Alemzadeh Ansari, Alžbeta Hegedűsová, Zhuqi Chen IN: Sustainability 15, 2527,

This review summarizes the recent research studies on the composition of biochar (BC) that controls carbon presence in soil, as well as BCs role in improving soil fertility and carbon sequestration. The main finding of the present work revealed that the high pyrolytic temperatures in BC production may have negative impacts on phyto-availability of essential nutrients.


Are temporary and permanent carbon stores interchangeable?

Robert Höglund on, Feb 7

„Are three trees worth one rock? Permanent storage is always best, but given realistic assumptions on discounting of future damages, as well as long-term climate adaptation – carbon storage lasting centuries could be made comparable to permanent storage. However, carbon re-released before peak warming needs to be replaced and cannot be equalized to permanent CDR.“


Nature-Honegger (2023): Toward the effective and fair funding of CO2 removal technologies

Matthias Honegger IN: Nature Communications 14, 534,

Carbon dioxide removal technologies are gaining prominence in academia, industry and policy, yet the need for substantial funding raises serious challenges. This comment outlines these issues and charts a path for the effective, systematic and fair mobilization of funds for removals.


Sendi et al. (2022): Geospatial analysis of regional climate impacts to accelerate cost-efficient direct air capture deployment

Marwan Sendi, Mai Bui, Niall Mac Dowell, Paul Fennell IN: One Earth 5,

DAC operational costs, and thus deployment potential, is dependent on performance, which can vary under different climate conditions. Here, to further develop the understanding of the impact of regional climate variation on DAC performance, the authors use high-resolution hourly based global weather profiles between 2016 and 2020 and weighted average capital costs to obtain DAC regional performance and levelized cost of DAC (LCOD). The authors found that relatively cold and drier regions have favorable DAC performance. Moreover, approximately 25% of the world’s land is potentially unsuitable due to very cold ambient temperatures for a substantial part of the year.


Dänemark erlaubt CO₂-Einlagerung unter der Nordsee

Spiegel online, 06.02.2023, 16.05 Uhr

„Dänemark hat erste Genehmigungen erteilt, damit Unternehmen in größerem Maßstab CO₂ unter dem Meeresgrund der Nordsee einlagern können. Die Zulassungen seien an den Konzern TotalEnergies und ein Konsortium aus den Unternehmen Ineos und Wintershall Dea gegangen, teilte das dänische Klimaministerium am Montag mit. Damit könnten die Arbeiten sofort beginnen. Es wird demnach damit gerechnet, dass im Rahmen der beiden Projekte ab 2030 bis zu 13 Millionen Tonnen Kohlendioxid jährlich unter dem dänischen Teil der Nordsee eingelagert werden können.“


Muss Klimaschutz weh tun?

Gerhard Schwarz, Neue Zürcher Zeitung, 07.02.2023, 05.28 Uhr

„In Debatten über den Klimaschutz taucht oft die Vorstellung auf, jedes Land müsse den CO2-Ausstoss bei sich zu Hause reduzieren. Da es sich beim Klimawandel um ein globales Problem handelt, wäre es jedoch sinnvoll, CO2-Emissionen dort zu reduzieren, wo mit den eingesetzten Mitteln die stärkste Wirkung erzielt werden kann. Das ist nicht unmoralisch, sondern effizient.“


Berger et al. (2023): Ocean dynamics and biological feedbacks limit the potential of macroalgae carbon dioxide removal

Manon Berger, Lester Kwiatkowski, David T Ho, Laurent Bopp IN: Environ. Res. Lett. 18 024039, DOI 10.1088/1748-9326/acb06e

The authors modify a high-resolution ocean biogeochemical model to simulate the consumption of dissolved inorganic carbon and macronutrients by idealised macroalgal cultivation in Exclusive Economic Zones. Under imposed macroalgal production of 0.5 PgC yr−1 with no nutrient feedbacks, physicochemical processes are found to limit the enhancement in the ocean carbon sink to 0.39 PgC yr−1 (1.43 GtCO2 yr−1), corresponding to CDR efficiency of 79%. Only 0.22 PgC yr−1 (56%) of this air–sea carbon flux occurs in the regions of macroalgae cultivation, posing potential issues for measurement, reporting, and verification.