
Reviewer 2 does geoengineering
By Andrew Lockley
Reviewer 2 quibbles with actual experts in Solar Radiation Modification and Carbon Dioxide Removal, before rejecting their work on spurious, spiteful and capricious grounds. You'd expect nothing less from R2.

Reviewer 2 does geoengineeringMar 22, 2025
00:00
54:15

Solar thermal DAC - Prats Salvado
Enrico Prats Salvado discusses the benefits and challenges of using the sun's heat for DAC desorb. Paper Prats-Salvado, E., Monnerie, N. & Sattler, C. Powering Direct Air Capture: Overview of Existing Concepts and the Overlooked Role of Concentrated Solar Thermal Technologies. Curr Sustainable Renewable Energy Rep 12, 8 (2025). https://doi.org/10.1007/s40518-025-00255-y
Apr 24, 202501:12:46

Water alternating gas injection - Nelson (&dog)
Claire Nelson, founder of Cella mineral storage, explains how underground injections of water alternating with CO2 might aid mineralsation.
Paper: Water-alternating-gas injections for optimized mineral carbon storage in basalt https://www.sciencedirect.com/science/article/abs/pii/S1750583624002263
Poppin' Fresh, more widely known as the Pillsbury Doughboy, is also, rather randomly, discussed https://en.wikipedia.org/wiki/Pillsbury_Doughboy
Apr 13, 202501:34:32

Biotech in CDR - Reginato
Paul Reginato explains how biotech can be applied to CDR. Paper: Biotechnology in direct air capture, enhanced weathering, and methane removal: emerging opportunities and gaps. https://doi.org/10.3389/fclim.2024.1440833
Mar 22, 202554:15

Get in the sea! Sinkco x Riverse — Boehman & Dorr
Can we just throw carbon in the sea - like a mobile phone with incriminating evidence on? Brenna Boehman and Erica Dorr from Sinkco and Riverse come on to discuss their Marine Carbon Burial Methodology with @geoengineering1
Mar 18, 202501:05:34

Octavia carbon, Kenyan DAC - Freimüller
Martin Freimüller introduces Octavia Carbon, explaining how they're making DAC work in Kenya's Great Rift Valley. Hosted by @geoengineering1
Mar 07, 202501:00:09

Calychar hydrochar - Suleman
Smoggies Humbul (Suleman), Omar, and Faizan discuss their research detailed in this press release https://www.tees.ac.uk/sections/news/pressreleases_story.cfm?story_id=8651
It's a fancy form of hydrochar, pimped by chemical manipulation.
Feb 27, 202501:00:52

COVID policy vs SRM policy - Patrick
Can COVID policy be compared to geoengineering policy? Hosea Olayiwola Patrick discusses "Reflections on COVID-19 Adaptive Responses as a Template for Climate Intervention-Geoengineering Engagement" with @geoengineering1 https://www.preprints.org/manuscript/202501.1715/v1
Feb 23, 202501:24:42

Sky whitening - Lemon
Would a whiter sky be noticeable, under SAI geoengineering? Ansar Lemon discusses what humans and animals could see. Paper: Under a not so white sky: visual impacts of stratospheric aerosol injection - Ansar Lemon et al 2025 Environ. Res. Lett. 20 024060 DOI 10.1088/1748-9326/ada2ae
A link to his music is here https://youtu.be/EpQ7rnQTDDU?si=ubVwa7p45uZ9mw_q
Feb 08, 202501:13:10

OAE legality - Murthy
Are you allowed to throw alkaline minerals into the sea? Ashwin Murthy explains how to do Ocean Alkalinity Enhancement, without ending up in jail.
Ashwin Murthy, Korey Silverman-Roati & Romany M. Webb, State Authority to Regulate Ocean Alkalinity Enhancement, Sabin Center for Climate Change Law, Columbia Law School, December 2024 (2024).
Available at: https://scholarship.law.columbia.edu/sabin_climate_change/237
Jan 12, 202501:16:30

SRM experts' opinions - McEvoy
David McEvoy discusses expert opinions on SRM. What do they think, and how do we know?
The strategic and governance implications of solar radiation modification: perspectives from delegates of international climate negotiations
Todd L Cherry et al 2025 Environ. Res. Lett. 20 014053
DOI 10.1088/1748-9326/ad9d62
Jan 05, 202501:00:43

Historic emissions & CDR - Hahn
Thomas Hahn discusses his paper on historical emissions and responsibility for them.
Hahn, T., Morfeldt, J., Höglund, R. et al. Estimating countries’ additional carbon accountability for closing the mitigation gap based on past and future emissions. Nat Commun 15, 9707 (2024). https://doi.org/10.1038/s41467-024-54039-x
Dec 28, 202444:30

Andean glaciers & SRM - Fernandez
Is it too late for SRM to save South American glaciers? Alfonso Fernandez discusses his paper on the impact of SRM on the glaciers of the Andes.
Fernández, A., Manquehual-Cheuque, F. & Somos-Valenzuela, M. Impact of Solar Radiation Management on Andean glacier-wide surface mass balance. npj Clim Atmos Sci 7, 257 (2024). https://doi.org/10.1038/s41612-024-00807-x
Dec 12, 202401:00:19

AGU SRM research ethics - Felgenhauer
AGU Ethical Framework Principles for SRM research
Tyler Felgenhauer, Duke University
https://news.agu.org/press-release/ethical-framework-climate-intervention-research/
Nov 29, 202401:02:29

Gentoo.earth - Kirby
Juliet Kirby explains how gentoo.earth uses AI to match carbon removal buyers and sellers. Despite @geoengineering1 trying his best to wind her up for lulz, she doesn't break character. NB this isn't paid promotion; gentoo hasn't sponsored this episode. No penguins (gentoo or otherwise) were harmed in the making of this episode.
Nov 18, 202431:53

Direct climate cooling overview - Baiman
Ron Baiman discusses his expansive paper summarising all known SRM and other direct climate cooling techniques
https://academic.oup.com/oocc/article/4/1/kgae014/7731760
Plus his letter to the International Maritime Organization
https://academic.oup.com/oocc/article/4/1/kgae008/7706251
Nov 10, 202401:03:32

SRM ethics - Hofbauer
Benjamin Hofbauer discusses 3 papers from his PhD, on the ethics of Solar geoengineering.
Hofbauer, B. (2023). Systemic risks and solar climate engineering research. Integrating technology ethics into the governance of systemic risks. Journal of Risk Research, 26(12), 1383–1395. https://doi.org/10.1080/13669877.2023.2288010
Hofbauer, B. (2023). Normative Uncertainty in Solar Climate Engineering Research Governance. Ethics, Policy & Environment, 1–20. https://doi.org/10.1080/21550085.2023.2216148
Benjamin Hofbauer. Techno-moral change through solar geoengineering: How geoengineering challenges sustainability. Prometheus. 2022. Vol. 38(1). DOI: 10.13169/prometheus.38.1.0082
Oct 30, 202438:52

Grain size in OAE - Moras
Charly Moras explains how grain size affects reaction kinetics in ocean alkalinity enhancement. Paper:- Effects of grain size and seawater salinity on magnesium hydroxide dissolution and secondary calcium carbonate precipitation kinetics: implications for ocean alkalinity enhancement https://egusphere.copernicus.org/preprints/2024/egusphere-2024-645/
Oct 23, 202452:53

Is OIF undead? - Buesseler
In this spooky Halloween episode, @geoengineering1 and Ken Buesseler investigate alleged sightings of Ocean Iron Fertilisation - which is rumoured to have risen from its unquiet grave. Paper: Next steps for assessing ocean iron fertilization for marine carbon dioxide removal. https://www.frontiersin.org/journals/climate/articles/10.3389/fclim.2024.1430957
Oct 15, 202458:15

Is cirrus thinning dead? Jeggle
Kai Jeggle explains to @geoengineering1 how off-target effects of cirrus cloud thinning mean that it can never be used effectively. Paper; Jeggle, K., Neubauer, D., Binder, H., and Lohmann, U.: Cirrus formation regimes – Data driven identification and quantification of mineral dust effect, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-2559, 2024.
Oct 06, 202457:50

Wood Vaulting - Zeng
Got wood? Looking for somewhere to stick it? Ning Zeng can solve your problem! @geoengineering1 learns all about how to do it properly.
Zeng, N., Hausmann, H. Wood Vault: remove atmospheric CO2 with trees, store wood for carbon sequestration for now and as biomass, bioenergy and carbon reserve for the future. Carbon Balance Manage 17, 2 (2022). https://doi.org/10.1186/s13021-022-00202-0
Sep 28, 202443:37

Coastal enhanced weathering - Geerts
Do not adjust your set; the fidelity of this recording is particularly poor. Luna Geerts and @geoengineering1 discuss coastal enhanced weathering of olivine. The paper is/was open to review, here. https://egusphere.copernicus.org/preprints/2024/egusphere-2024-1824/
Sep 21, 202445:50

Near term Arctic SRM - Wake Smith
What would a mid-century polar geoengineering program look like? What airports and aircraft would be needed - and at what cost? Wake Smith answers all these questions.
Sep 15, 202401:22:22

Extra-tropical cyclones - Reboita
How does SAI affect extra-tropical cyclones? Michelle Simões Reboita explains during a tight interview slot, but @geoengineering1 fails to understand (it takes him at least an hour to understand ANYTHING). With fluency approaching that of the Trump Biden debate, he stumbles through the episode, only occasionally realising where he is and what he's doing. Can anyone do a better job? Please tweet us, if you can... Please?
Paper: Response of the Southern Hemisphere extratropical cyclone climatology to climate intervention with stratospheric aerosol injection. https://iopscience.iop.org/article/10.1088/2752-5295/ad519e/meta
Jul 04, 202444:20

Controlling MCB - Walker Lee Part 1
What control can we exercise over MCB? Should it be confined to small, climatically sensitive areas - or expanded at great cost, to minimise inter-regional disparities? Walker Lee discusses the issue in depth. (See PT 2 for a discussion on disability and diversity).
Jack's first paper: https://doi.org/10.22541/essoar.171322700.02512514/v1
Jack's second paper: https://doi.org/10.22541/essoar.171201044.45268441/v1
May 12, 202401:16:36

Disability & ideological diversity in academia - Walker Lee, Part 2
We've extracted this very interesting discussion from Walker Lee's new episode, because a) it's a standalone section and b) the main episode was already quite long. Here, Walker Lee describes in vibrant and very personal terms his own academic journey, touching on important issues of ideological diversity and disability discrimination. It's not trad R2, but we liked it. Enjoy!
May 12, 202428:13

Warm pool & SAI - Günther (FIXED)
Moritz Günther tries valiantly to get @geoengineering1 to understand the atmospheric dynamics of SAI's impacts on the warm pool, but it's rather like watching him trying to train a baboon to use Photoshop - there's some engagement, and the occasional flash of comprehension before it all gets too much for him.
NB this is the FIXED version - the original had a couple of important errors of sign from Günther. If you've listen to the old version, pls see this important author note "the part where I say it's destabilising... should actually be stabilising... roughly at 1:10:30 - 1:11:00. The part where I say we would need less aerosol if the Brewer-Dobson circulation mechanism exists but we would actually need more is around 1:21:30 - 1:22:00." (timestamps from old episode) And BTW, props to him for a) checking b) fessing up. Science progresses one correction at a time.
Günther, M., Schmidt, H., Timmreck, C., and Toohey, M.: Why does stratospheric aerosol forcing strongly cool the warm pool?, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-429, 2024.
May 04, 202401:27:07

SAI and international conflict - Morrissey
William Morrissey explains how SAI could lead to conflict and counter-geoengineering. @geoengineering1 isn't convinced it will all end so badly.
Avoiding atmospheric anarchy: Geoengineering as a source of interstate tension
William Morrissey
https://doi.org/10.1177/27538796231221597
Apr 16, 202401:24:53

Mass participation OAE tests - Bach
Roll up! Roll up! Grab your buckets, and get ready to do a science! Bach is back (again) to discuss institutional collaboration and citizen science in OAE.
Bach, L. T., Ferderer, A. J., LaRoche, J., and Schulz, K. G.: Technical note: Ocean Alkalinity Enhancement Pelagic Impact Intercomparison Project (OAEPIIP), EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-692, 2024
Identifying the Most (Cost-)Efficient Regions for CO2 Removal With Iron Fertilization in the Southern Ocean
Lennart T. Bach, Veronica Tamsitt, Kimberlee Baldry, Jeffrey McGee, Emmanuel C. Laurenceau-Cornec, Robert F. Strzepek, Yinghuan Xie, Philip W. Boyd
First published: 16 November 2023
https://doi.org/10.1029/2023GB007754
Apr 13, 202450:30

Holocene DAC, chemistry & biz - Timofte
How do you establish and grow a DAC company? Anca Timofte has utilised a career leg-up from Climeworks to start her own DAC outfit, with some pretty fancy chemistry. @geoengineering1 gets the lowdown on how she did it - and what the future challenges are https://theholocene.co/
Apr 07, 202401:22:10

Who gets to use CDR? - Bellona; Paul
Is the supply of carbon removal fundamentally limited, and how should it be allocated? Comrade Allanah Paul from Bellona sends @geoengineering1 to the reeducation camps in an attempt to expunge his bourgeois thinking. report: https://www.negemproject.eu/wp-content/uploads/2023/11/D6.5_Who-should-use-NETPS.pdf
Apr 06, 202401:06:18

Olivine ecotoxicity - Flipkens
Gunter Flipkens explains why everyone is worried about heavy metals leaching from olivine coastal weathering experiments. Then he explains how he tests the exact toxicity to animals, plus how to reduce it. Thesis link https://www.researchgate.net/publication/379406915_Coastal_enhanced_olivine_weathering_for_climate_change_mitigation_investigating_the_CO2_sequestration_potential_and_ecotoxicological_risks
Apr 02, 202448:46

MCB with drones - Claudel
Christian Claudel comes on to explore the issues around using drones to distribute MCB particles. These are made by anti-solvent precipitation (much like diluting Ricard spirit). Despite @geoengineering1 being AN ACTUAL AUTHOR on the paper he still finds plenty of opportunities for nitpicking.
Paper: Marine-cloud brightening: an airborne concept
Christian Claudel, Andrew John Lockley, Fabian Hoffmann and Younan Xia
DOI 10.1088/2515-7620/ad2f71
Mar 12, 202401:37:40

Littoral weathering & academic culture - Fuhr
Michael Fuhr gives @geoengineering1 news on what happens when you throw rocks in the sea (yawn). Then they go on a massive rant about how Gen Z academics don't know how to party anymore (yey!). But which one of them ended a conference locked in a laundry cage being rolled through a hotel foyer? Find out, inside.
Paper
https://doi.org/10.3389/fclim.2024.1338556
This article is part of the Research Topic
Quantifying Carbon Removal by Negative Emissions Technologies
Alkaline mineral addition to anoxic to hypoxic Baltic Sea sediments as a potentially efficient CO2-removal technique
Mar 12, 202401:12:26

Future of CDR - Hoglund
What could be the eventual scale of the CDR market? What technologies will it use? And how do choices made today affect where it ends up? Robert Hoglund discusses with @geoengineering1
Some works discussed
CDR.fyi annual report
https://www.cdr.fyi/blog/2023-year-in-review
Carbon removal is not a finite resource
https://marginalcarbon.substack.com/p/carbon-removal-is-not-a-finite-resource
Emergent methane mitigation and removal approaches: A review
Ishita Mundra, Andrew Lockley
https://doi.org/10.1016/j.aeaoa.2023.100223
Mar 09, 202401:28:07

Stratospheric dehydration - Schwarz
Joshua Schwarz explains how dispersing ice nucleating particles in one tiny region of the tropical tropopause layer off Northern Australia can address around 1pc of global warming. He also discusses his involvement in the SABRE stratospheric flights. Paper: Considering intentional stratospheric dehydration for climate benefits
DOI: 10.1126/sciadv.adk0593
Other papers discussed
Pyrocumulonimbus affect average stratospheric aerosol composition
J. M. KATICH
DOI: 10.1126/science.add3101
Marine-cloud brightening: an airborne concept
Christian Claudel, Andrew John Lockley, Fabian Hoffmann and Younan Xia
DOI 10.1088/2515-7620/ad2f71
Mar 08, 202401:22:45

Messing with nature - Woodhouse
What is nature? Does it matter beyond its direct usefulness? Do animals only have rights if they're conscious? When did man become morally responsible for environmental degradation? When can and should we fiddle with the natural world? Elliott Woodhouse explains the differing views to @geoengineering1. A blog post is available, summarising his PhD https://www.sheffield.ac.uk/lc3m/blogs/phd-spotlight-elliott-woodhouses-ethics-climate-engineering
Jan 22, 202401:22:34

Agent based models - Perkins
NPC vs IAM. Oliver Perkins explains why simple agent-based models (non playable characters, if you like) might outperform the integrated assessment models that have led to such outlandish predictions for CDR.
Paper: Toward quantification of the feasible potential of land-based carbon dioxide removal
https://doi.org/10.1016/j.oneear.2023.11.011
Jan 19, 202401:07:46

Sorbents for all seasons - Jones
The highly prolific Chris Jones thoroughly intimidates the normally boisterous @geoengineering1, while discussing sorbents that can tolerate a wide range of climate conditions.
Paper Sub-Ambient Temperature Direct Air Capture of CO2 using Amine-Impregnated MIL-101(Cr) Enables Ambient Temperature CO2 Recovery
https://doi.org/10.1021/jacsau.1c00414
Here's some more links about Chris and the subjects discussed in this episode.
DAC bibliometric analysis
https://www.sciencedirect.com/science/article/pii/S2772826922000086
https://www.sciencedirect.com/science/article/pii/S277282692300010X
DirACC Publication list (GT DAC Center)
https://sites.gatech.edu/dac-center/publications/
Jones web page:
https://jones.chbe.gatech.edu/dr-jones/
Jones Google Scholar page:
https://scholar.google.com/citations?user=ltWKpYgAAAAJ&hl=en
Jones Wikipedia page:
https://en.wikipedia.org/wiki/Christopher_W._Jones
Jan 09, 202401:29:06

Blue carbon - Reithmaier
Gloria Reithmaier talks to @geoengineering1 about coastal blue carbon, work/life balance, and being a mum in academia. Paper: Reithmaier, G.M.S., Cabral, A., Akhand, A. et al. Carbonate chemistry and carbon sequestration driven by inorganic carbon outwelling from mangroves and saltmarshes. Nat Commun 14, 8196 (2023). https://doi.org/10.1038/s41467-023-44037-w
Jan 03, 202451:26

Festive Holly (Jean Buck)
Celebrate Xmas day with Holly, discussing Solar geoengineering research in the global public interest: A proposal for how to do it https://www.sciencedirect.com/science/article/pii/S2590332223005481
Dec 25, 202301:21:13

How to support a sunshade - Maheswaran
How can you make a sunshade stay in place? How can you make it beam down solar power to Earth? @geoengineering1 finds out from Tharshan Maheswaran.
Paper - International planetary sunshade concept with a function-integrated and scalable support structure based on coreless filament winding DOI 10.1088/1742-6596/2526/1/012113
Dec 23, 202301:16:23

Ethics of Volcano Geoengineering
- Cassidy
Should the army be allowed to blow people up with a volcano? If your geothermal power plant triggers an eruption, is that just a risk of doing business? Should we fiddle with volcanoes to make them safer? Is even researching this opening a can of worms? Gideon Futurman interviews Michael Cassidy (giving @geoengineering1 a month long editing nightmare, but with results we hope you'll like).
Paper: The Ethics of Volcano Geoengineering
Michael Cassidy, Anders Sandberg, Lara Mani
https://doi.org/10.1029/2023EF003714
Dec 13, 202301:03:54

HPAC takeover! Overshoot commission - Field
"Good afternoon, Reviewer 2 listeners. Some of us at the Healthy Planet Action Coalition (www.healthyplanetaction.org) have noticed that a few months ago Reviewer 2 experienced a security breach orchestrated by archrival Challenging Climate. Now normally we would refrain from taking advantage of poor Reviewer 2, but we sensed an opportunity that we couldn’t resist and decided to jump into the breach with this discussion about the recent report of the Climate Overshoot Commission (COC) between Chris Field, Stanford Professor and advisor to the COC, and Mike MacCracken, HPAC Steering Circle member and former Executive Director of the Office of the US Global Change Research Program.
The Climate Overshoot Commission report "Reducing the Risks of Climate Overshoot" was released on September 14: https://www.overshootcommission.org/_files/ugd/0c3b70_bab3b3c1cd394745b387a594c9a68e2b.pdf. While the COC did not solicit public input, it did hold a series of meetings to learn and discuss the full range of questions facing the international community in dealing with the risk of climate overshoot. Their 4-part high-level recommendations were summarized in the acronym CARE, for Cut (emissions), Adapt, Remove (CO2), and Explore (SRM). Specifically, its recommendation on climate intervention advocated expanding research while placing "a moratorium on the deployment of solar radiation modification and large-scale outdoor experiments that would carry risk of significant trans-boundary harm. "
Nov 21, 202301:04:22

Pinatubo’s effect on ozone - Peng
Want to know *exactly* how Pinatubo affected ozone? After a marathon 6h edit, @geoengineering1 has finally managed to get this Yifeng Peng interview sounding OK. Paper: Perturbation of Tropical Stratospheric Ozone Through Homogeneous and Heterogeneous Chemistry Due To Pinatubo https://doi.org/10.1029/2023GL103773
Oct 28, 202347:41

Cloud seeding law - Simon
Manon Simon discusses her thesis on the legal overlap between cloud seeding and MCB. What can we learn and apply from decades of cloud seeding regulation?
Oct 28, 202301:05:09

"Year of the slags" - Bullock
Liam Bullock talks about his Horizon-funded work on slags, tailings and overburden. How can these different wastes be used for CO2 removal?
International Journal of Greenhouse Gas Control
Volume 129, October 2023, 103990
Experimental investigation of multiple industrial wastes for carbon dioxide removal strategies
https://doi.org/10.1016/j.ijggc.2023.103990
Oct 20, 202349:23

Can we trust SRM papers? Reynolds
Jesse Reynolds shows how many SRM papers overestimate risks and underestimate benefits.
Paper: "Communication of Solar Geoengineering Science: Forms, Examples, and Explanation of Skewing" https://journals.sagepub.com/doi/10.1177/20530196221095569
More papers are at https://jreynolds.org/
Sep 29, 202301:00:24

Does SRM's location affect global temperature? Zhang
The Radiative Forcing Pattern Effect on Climate Sensitivity
https://essopenarchive.org/users/535851/articles/655683-the-radiative-forcing-pattern-effect-on-climate-sensitivity
Sep 25, 202301:05:53

Seaweed fertilizers (and a kelp violin) - Sheppard
Emily Sheppard talks about how the nutrients used by seaweed affect its usefulness for CDR. She then plays a violin made of seaweed.
Paper: https://onlinelibrary.wiley.com/doi/10.1111/jpy.13381
Kelp violin link: https://www.youtube.com/watch?v=e2nHGNF_Ar0
Sep 21, 202357:30

Who pays for historic CDR? Torvanger
How can countries share the cost of cleaning up historic emissions? A croaky Reviewer 2 finds out from Asbjørn Torvanger.
What If Country Commitments for CO2 Removal Were Based on Responsibility for Historical Emissions?
by Asbjørn Torvanger
CICERO Center for International Climate Research, Gaustadalléen 21, 0349 Oslo, Norway
Energies 2023, 16(11), 4350; https://doi.org/10.3390/en16114350
Sep 09, 202301:03:29