Konstantin Weber @konstantinweber.bsky.social · 17h(Jus) another limitation of IAMs? Or is there anything else you would infer from that? 100
Konstantin Weber @konstantinweber.bsky.social · 22/09/2026Interesting! Is there an (up-to-date) emission scenario available, too (I didn’t find anything but also didn’t look for long) ? I stopped believing in temperature curves alone 000
Reposted by Konstantin WeberThe New York Times @nytimes.com · 14/09/2026Breaking News: The E.P.A. is said to be planning to announce that the U.S. will no longer limit climate pollution from power plants.nyti.msE.P.A. Will Erase Limits on Climate Pollution From Power PlantsGeneration of electricity is the second largest source of carbon dioxide and other planet-warming gases in the United States. 265728477
Reposted by Konstantin WeberDavid Ho @davidho.bsky.social · 12/09/2026Treating this as an unstoppable race, and accepting the "endgame" of runaway warming, is a reckless gamble that should never be decided in a boardroom alone. Betting on future carbon removal to fix today's emissions requires far more confidence than the evidence supports. 63006412
Reposted by Konstantin WeberRuben Prütz @rubenpruetz.bsky.social · 10/09/2026In a new Comment, published this week in #Nature Reviews Clean Technology and co-led with Quirina Rodriguez Mendez, we discuss ten prominent #narratives about the role of carbon dioxide removal (CDR) in the current academic #discourse. 📚💭 doi.org/10.1038/s443...doi.orgMapping conflicts in carbon removal narratives - Nature Reviews Clean TechnologyCarbon dioxide removal has been described both as a mitigation necessity and as a risk to mitigation ambition or sustainability in the academic literature. This Comment examines the assumptions underl... 2229
Konstantin Weber @konstantinweber.bsky.social · 10/09/2026Absolutely agree! iopscience.iop.org/article/10.1...iopscience.iop.orgAnchoring overshoot in realityAnchoring overshoot in reality, Weber, Konstantin, von Rothkirch, Juanita, Brunner, Cyril, Knutti, Reto 020
Konstantin Weber @konstantinweber.bsky.social · 09/09/2026roughly correct, but the 500 MtCH4/year number is too high. Importantly, we need *methane AND CO2* emission reductions, so calling methane the "highest-leverage climate lever" is a bit misleading in my view. 110
Konstantin Weber @konstantinweber.bsky.social · 09/09/2026Overshoot of 1.5 °C is inevitable, but don't forget that we need stringent methane mitigation to keep warming to below 2 °C. Without methane mitigation peak warming below 2 °C becomes unlikely, even with extremely ambitious CO2 emission reductions! www.nature.com/articles/s43247-026-03832-1nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 031
Reposted by Konstantin WeberMike Sparrow @drmikesparrow.bsky.social · 09/09/2026The trail of clues that our planet might be heating faster than we realised: www.bbc.co.uk/news/article...bbc.co.ukThe trail of clues that our planet might be heating faster than we realisedA curious online row over this summer's heatwaves points to a wider - and worrying - shift in climate science. 021
Reposted by Konstantin WeberIngrid Brodnig @brodnig.bsky.social · 08/09/2026Mithilfe erbeten: Hat hier jemand die Erfahrung gemacht, wegen KI den Job zu verlieren? Oder gab es im eigenen Unternehmen Überlegungen dazu? Mich würden (anonymisiert) solche Erfahrungen journalistisch interessieren - schaue auch in meine DMs, also gerne dort schreiben Bin über RTs dankbar! 🙏 38369442
Reposted by Konstantin WeberRobert Finger @robertfinger.bsky.social · 07/09/2026‚Assessing the Environmental, Economic and Social Impacts of a Greenhouse Gas Emission Tax in Swiss Agriculture‘ New paper in the Journal of Agricultural Economics. Led by Marta Tarruella, and with Nadja El Benni, Eva Winter, Robert Huber, Gabriele Mack onlinelibrary.wiley.com/doi/10.1111/... 085
Konstantin Weber @konstantinweber.bsky.social · 04/09/2026Even when it comes to peak warming, methane might help a lot: www.nature.com/articles/s43...nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 010
Konstantin Weber @konstantinweber.bsky.social · 03/09/2026Just to understand correctly: Do you mean "CDR" (also part of mitigation) or "net negative CO2 emissions"? 100
Konstantin Weber @konstantinweber.bsky.social · 03/09/2026concerning overly optimistic assumptions regarding overshoot: iopscience.iop.org/article/10.1...iopscience.iop.orgAnchoring overshoot in realityAnchoring overshoot in reality, Weber, Konstantin, von Rothkirch, Juanita, Brunner, Cyril, Knutti, Reto 100
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Just out of interest: DACCS and BECCS are considered as geoengineering and part of a UN moratorium? I am hearing this for the first time. 120
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Depends on who you ask. Very unlikely in my view: www.newscientist.com/article/2587... iopscience.iop.org/article/10.1...iopscience.iop.orgAnchoring overshoot in realityAnchoring overshoot in reality, Weber, Konstantin, von Rothkirch, Juanita, Brunner, Cyril, Knutti, Reto 010
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Agriculture, fossil fuel production and distribution, and the the waste sector :) 220
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Thank you. I was more referring to the framing of the UN report, as I did not see any discussion around what duration of OS is discussed as plausible. Clearly, the earlier the better, but I worry that a short OS period is as realistic as the below 1.5 °C scenarios produced by models 10 years ago. 110
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Zur Ergänzung: www.srf.ch/audio/rendez... Und zum Lesen: www.carbonbrief.org/guest-post-w...srf.chETH-Forschende warnen vor unterschätztem MethanproblemViele Staaten haben ihre Versprechen zur Reduktion von Methan bisher nicht eingelöst. Auch die Schweiz hat zwar ein Reduktionsziel festgelegt, aber keinen konkreten Umsetzungsplan. Forschende der ETH ... 010
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026The overshoot figure (maybe deliberately?) does not have a scale for the x-axis. I keep wondering about the time scale envisaged for the return to 1.5 °C... 250
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Maybe of interest: Peak warming depends on methane mitigation, too. Without methane mitigation we will exceed even 1.8 °C with ambitious net zero targets. See below or www.nature.com/articles/s43... 1116
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026If you want to know more: Post by @brunncy.bsky.social : lnkd.in/p/e6RVr4tS Behind the paper: communities.springernature.com/posts/limiti... SRF radio broadcast: www.srf.ch/audio/rendez... * Lena Brun, @retoknutti.bsky.social, @brunncy.bsky.social @ethz.ch @usyseth.bsky.socialnature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 250
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026• Published values of the 2 °C remaining carbon budget lie around 1000-1150 GtCO₂ for 2025. We find that this implies CH₄ emissions decreasing by 27-35% in 2020-2050. With lacking CH₄ mitigation, the 2 °C budget is far smaller than communicated and the 1.7 °C budget is already exhausted.nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 150
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026• A net zero CO₂ target for 2050 requires CH₄ emissions to fall by about two thirds relative to 2020 to keep warming at 1.7 °C. • Cutting one third of human-caused CH₄ emissions by 2030 relative to 2020 lowers peak warming by 0.15 °C. 0.05 °C come at no net cost (the fossil fuel supply chain).nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 192
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Methane mitigation is not a substitute for CO₂ mitigation. We need both. Some insights (all warming values at 50% likelihood): • No CH₄ mitigation leads to warming peaking at almost 2 °C, even if net zero CO₂ were reached by 2050.nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 171
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026By treating CH₄ emissions separately, we systematically quantify how much CH₄ emissions need to fall to be consistent with a given warming level. We derive minimum compatible CH₄ reduction targets for existing net zero CO₂ or net zero GHG targets.nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 171
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026CH₄ stays in the atmosphere for about a decade, but CO₂-induced warming is irreversible for millennia.nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 161
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Climate targets and discussions around emission reductions often combine CO₂ and CH₄ into “CO₂ equivalents”, but such an aggregation is always a simplification. CO₂ and CH₄ behave completely differently (comparable to the difference between 🍗 and 🍜): www.carbonbrief.org/guest-post-w...nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 151
Konstantin Weber @konstantinweber.bsky.social · 02/09/2026Methane Mitigation Matters We* have a new paper out today and the key message is that keeping warming well-below 2 °C requires strong reductions in methane (CH₄) emissions. Link to paper: www.nature.com/articles/s43... @carbonbrief.org guest post: www.carbonbrief.org/guest-post-w...nature.comLimiting warming by CO2 and methane mitigation in an expanded scenario space - Communications Earth & EnvironmentSystematically mapping peak warming across two main choices for climate policy – when carbon dioxide reaches net zero emissions and how fast methane emissions are cut – shows that near-term methane mi... 55826
Reposted by Konstantin WeberCarbon Brief @carbonbrief.org · 01/09/2026NEW – Guest post: Why tough methane cuts are crucial for keeping warming ‘well-below’ 2C | Written by @konstantinweber.bsky.social @retoknutti.bsky.social @brunncy.bsky.social Read here: buff.ly/rd13QpI 03514
Konstantin Weber @konstantinweber.bsky.social · 31/08/2026Amazing, thank you! I was not aware of the extent of the problem with CCS deployment and *how much* carbon prices increase in models. I recently contributed a paper that looks at sth related, but in the context of overshoot, maybe of interest: iopscience.iop.org/article/10.1...iopscience.iop.orgAnchoring overshoot in realityAnchoring overshoot in reality, Weber, Konstantin, von Rothkirch, Juanita, Brunner, Cyril, Knutti, Reto 091
Konstantin Weber @konstantinweber.bsky.social · 31/08/2026These numbers are pretty insane and I was not aware of this either. Is this due to assumed cost reductions of CCS put into IAMs? (To me, it increasingly looks like you get out what you put in, but I hope that I will be proven wrong by experts on IAMs.) 430
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026(1) www.unep.org/resources/em... (2) iopscience.iop.org/article/10.1... (3) essd.copernicus.org/articles/18/... (4) www.nature.com/articles/s41... (5) granthaminstitute.com/2023/11/29/o...unep.orgEmissions Gap Report 2025UNEP’s Emissions Gap Report 2025: Off Target finds that available new climate pledges under the Paris Agreement have only slightly lowered global temperature rise over the course of this century, leav... 111
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026A lack of strong near-term mitigation commits many generations to live under an overshoot of 1.5 °C, with impacts that could have been avoided. For scientists: Please stop drawing symmetric overshoot pathways. 152
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026From a current perspective, long-term exceedance of 1.5 °C seems much more plausible than a fast return to it. In any case, neither our children nor grandchildren are likely to ever experience warming returning to 1.5 °C. 113
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026Are such overshoot scenarios desirable? They are clearly more desirable than warming stabilizing at a higher level without returning to 1.5 °C. Are overshoot scenarios plausible or even likely as often depicted? Our answer: Absolutely not. 102
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026Together, these three elements lead to an overly rosy communication that creates the expectation that a return after overshoot will be quick and easy. We and others argue that it is not (4, 5). 121
Konstantin Weber @konstantinweber.bsky.social · 24/08/20263) The models that generate future emission scenarios are structurally prone to generating overshoot pathways. Temperature decline faces barriers in the real world that are not represented in such models that explore cost-optimal trajectories. 122
Konstantin Weber @konstantinweber.bsky.social · 24/08/20262) Strong cooling rates depend on overly optimistic assumptions regarding CO2 removal to compensate for emissions that took place in the past. Currently, we are even failing to reduce CO2 emissions globally (3), let alone plan for net negative emissions. 122
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026We trace the prevalence of overly optimistic temperature decline in overshoot pathways back to three interconnected problems: 1) The irreversibility of CO2-induced warming is non-intuitive, even to experts. 121
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026In a new perspective paper, we argue that the current thinking and communication around global temperature decline after peak warming is far too optimistic. We show that even under extremely optimistic assumptions, the time above 1.5 °C will extend well beyond 2100, and probably much longer. 233
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026Just to be clear, this would require net negative CO2 emissions on the order of today’s human-caused positive CO2 emissions and an industry to take out CO2 from the atmosphere about the size of the current fossil fuel industry! 121
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026The rate of global temperature decline is largely determined by the rate of net negative CO2 emissions. Illustrations of “overshoot” routinely show temperature trajectories that are almost symmetric in the increase and decrease in global temperatures. 101
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026Long-term warming will soon exceed 1.5 °C (1). To align this reality with the ambition of the Paris Agreement to limit warming to 1.5 °C, there is a rise in so-called “overshoot scenarios”. In an overshoot scenario, global warming temporarily exceeds a temperature limit and later returns to it (2). 101
Konstantin Weber @konstantinweber.bsky.social · 24/08/2026Temperature overshoot means more than cleaning up a slightly bigger mess a little later. TL;DR: If we ever return to 1.5 °C, it will likely take centuries. The way overshoot scenarios are often sketched fails to highlight that. iopscience.iop.org/article/10.1...iopscience.iop.orgAnchoring overshoot in realityAnchoring overshoot in reality, Weber, Konstantin, von Rothkirch, Juanita, Brunner, Cyril, Knutti, Reto 198
Reposted by Konstantin WeberGergana Gyuleva @ggyuleva.bsky.social · 20/08/2026Radiation Trends Point to Higher Future Warming ‼️ 🌡️ How sensitive is Earth's climate to increasing CO₂ concentrations? Fresh insights in our new study: agupubs.onlinelibrary.wiley.com/doi/10.1029/... @retoknutti.bsky.social @erichfischer.bsky.social @sebastian-sippel.bsky.socialagupubs.onlinelibrary.wiley.comRecent Temperature and Energy Imbalance Trends Point to Higher Estimates of Future WarmingRecent surface warming and top-of-atmosphere energy imbalance point to higher future warming than previously estimated Previous constraints on transient climate response using observed surface te... 02410
Konstantin Weber @konstantinweber.bsky.social · 03/05/2026I have the pleasure to kick off #EGU tomorrow: First session, first talk 🥳! So get up "early" on Monday morning and join CL3.2.1 at 8:30 in Room 0.49/50! I'll present how methane mitigation affects the remaining carbon budget and peak warming🌡. There are also many great talks afterwards! 050
Konstantin Weber @konstantinweber.bsky.social · 13/02/20269/ Our data are publicly available. And finally, the paper can be found here: www.nature.com/articles/s41...nature.comTracking country-level mitigation progress using NGHGI-consistent carbon budgets - Nature CommunicationsThis study shows that aligning remaining carbon budgets with national greenhouse gas inventory accounting reduces the global 1.5 ∘C (50%) budget by ~100 GtCO2, with possible depletion around 202... 000