Lmst

More on Bananas from North Atlantic in 2023, here by #MattEngland, Stefan #Rahmstorf et al
https://www.nature.com/articles/s41586-025-08903-5

They also wrote prose on the Conversation https://theconversation.com/unprecedented-heat-in-the-north-atlantic-ocean-kickstarted-europes-hellish-2023-summer-now-we-know-what-caused-it-258061

Low surface wind speed led to shallower-than-normal ocean mixing which enabled heating the surface more.
Less clouds from shipping SO2 were only marginally responsible and only in small pockets.

Okay. But where did the wind go?
Surface wind is impacted by jetstream. And I think, the jetstream got diverted in June and July 2023 to Northern Greenland. Due to low spring snow cover in Eastern Canada which led to dry soil – which in turn gets hotter than wet soil.
And according to
"Summer atmospheric circulation over Greenland in response to Arctic amplification and diminished spring snow cover over Canada" by
Preece et al 2023
https://www.nature.com/articles/s41467-023-39466-6
that hot soil in Eastern Canada leads to a High over Greenland – and a low over the #ColdBlob
East Canada was ablaze in June July 2023 suggesting dry and hence hot soil =perfect conditions for a North Greenland High, diverting the jetstream.

#climatechange #ocean #Atlantic #Canada #CanadaFires #jetstream #Arctic #ArcticAmplification

2 maps of the Northern hemisphere for fire activity and sea surface temperature in June and July 2023 in % of their all-time maximum in the grid cell.
Orange is highest-ever fire activity.
Blue-white is fire activity but grid cell had burned before and intensity didn't reach all-time maximum in June or July 2023.

East and also West Canada, and East Siberia show large areas with highest-ever fire activity.
Mexico, California, East of Turkey, and all of Eastern China also have much fire activity but the colours are blue-ish white so they had burned before and didn't reach their maximum in June July 2023.

Source fires: Copernicus GFAS
Source SST: NOAA satellite obs Coast Watch
image generator: Panoply

Figure 9 from a paper on how low snow cover in Canada's spring leads to drying of soil in summer, which in turn leads to the jetstream meandering in a particular way: a Low over Canada in summer moves the jet North to a High over Greenland and back South to a Low over the Cold Blob.

Paper: " Summer atmospheric circulation over Greenland in response to Arctic amplification and diminished spring snow cover over Canada"
Preece et al 2023
https://www.nature.com/articles/s41467-023-39466-6

#Europa erwärmt sich schneller als jeder andere Kontinent, mit deutlich spürbaren Folgen wie #Hitzewellen, #Dürren und #Starkregen.

Laut Stefan #Rahmstorf seien viele Länder beim #Klimaschutz aktiver als Deutschland. Der Eindruck, Deutschland sei ein Vorreiter, sei nicht haltbar.

Besonders betroffen: Regionen in hohen Breitengraden und solche mit gestörtem #Jetstream.

https://www.zdf.de/nachrichten/politik/klima-vorreiter-deutschland-europa-100.html

#Klimawandel #Extremwetter #Emissionen #Kohleausstieg #Gesundheit #Copernicus #IPCC #Klimapolitik

@docjosiahboone

@rahmstorf

Eben - Stefan #Rahmstorf kennt sich da sehr gut aus. Ich folge ihm hier bei Mastodon. Und alles was ich von ihm mitbekommen habe, geht in die Richtung: es ist ernst!
Die #amoc hat einen Kipppunkt, niemand kann seriös sagen, wann genau der erreicht wird, ob er im schlimmsten Fall schon überschritten ist. Aber alles was ich an Berichten in den letzten 2 Jahren mitbekommen habe, sagt die AMOC hat sich bereits deutlich abgeschwächt. Mindestens 15%?

Vom Ideologen zum Verwirrten

Gestern hatte ich herausgefunden, daß ein Fediverse-Teilnehmer (männlich!) mich geblockt hatte, weil ich wohl zu den "3 Ideologischen" gehörte, die er neu auf seine Blockliste gesetzt hatte.

Kann der Gute bitte mal eine Trophäe bekommen?

Im Zuge der Erforschung, was den Betreffenden zum Blocken veranlaßt haben könnte, war ein Bericht aus der ehrenwerten Springer-Zeitung DIE WELT aufgefallen. Autor: Axel Bojanowski.

Nun hab ich zur Abrundung etwas recherchiert, was der Wissenschaftsjournalist Bojanowski schreibt und wie er argumentiert.

Einen ersten Überblick hat mir Wikipedia verschafft, einen zweiten lieferte seine Kontroverse mit Stefan Rahmstorf @rahmstorf über ein Thema ( #Paläoklimatologie ), das in Detailfragen interessant sein mag, aber nicht im Grundsatz:
http://axelbojanowski.de/bojanowski-antwortet-rahmstorf/

Wenn ich also ein "Ideologischer" sein sollte, dann wegen begrenzter Gehirnschmalzmenge nur als kleine Funzel in einem Lichtermeer.

#ideologisch #verwirrt #Klima #Klimakrise #Wissenschaft #Wissenschaftsjournalismus #AxelBojanowski #Rahmstorf

Stefan #Rahmstorf im Interview:

Es geht um Machen statt Reden

https://www.klimareporter.de/erdsystem/es-geht-um-machen-statt-reden

#GWUP Der Klimawissenschaftler Stefan Rahmstorf hat nach eigenen Angaben „mehrfach sachliche Fehler von Bojanowski bei Redaktionen beanstandet“. #Bojanoswki hatte zudem die Meeresspiegeluntersuchungen vom Meeresforscher Simon #Holgate so interpretiert, dass es laut den Daten keine Beschleunigung des Anstiegs des Meeresspiegels gebe. Laut #Rahmstorf antwortete ihm Holgate auf Nachfrage dazu, dass Bojanowski seine Ansichten falsch dargestellt habe. @Rahmstorf@fediscience lastet Bojanowski an, immer wieder Narrative von Lobbyisten der fossilen Energien in „Mainstream-Medien“ übernommen und so salonfähig gemacht zu haben; so habe Bojanowski in einem Artikel in der #Welt vom 15. August 2004 in perfider Weise den Eindruck erweckt, die Autoren der sogenannten Hockeyschlägerkurve hätten den Verlauf ihrer Temperaturkurve später selbst wesentlich korrigiert. Tatsächlich stammte die angebliche Korrektur aber von zwei der Klimaleugnerszene nahestehenden Fachfremden und war nie in einer seriösen Fachzeitschrift erschienen. Wikipedia

A new paper on #AMOC

Prose summary by the authors https://theconversation.com/meltwater-from-greenland-and-the-arctic-is-weakening-ocean-circulation-speeding-up-warming-down-south-238302

Free ePDF https://www.nature.com/articles/s41561-024-01568-1.epdf?sharing_token=O3cvnzvEWDHiaPGAV-CB3dRgN0jAjWel9jnR3ZoTv0M2PsD_MIel1A6mz6UbuhaTQSv4VfXkSU9okrbFGA0gy1etRpvwJw0P0tMsHg9ro8Nv1h-GiKg-3Km08jevWj3MVZ6uFzlIrUTv-X1bF8I0K8crc3qdtYsHtgUTx9fE2Zc%3D

actual paper https://www.nature.com/articles/s41561-024-01568-1 #Pontes et al 2024

tldr: by adjusting #Greenland meltrate to actually observed accelerated rate which is underestimated in standard climate models, they are now able to explain the observed increase in SST and salinity in the South #Atlantic with a slowdown of the AMOC in the past decades , matching the slowdown rate calculated by #Rahmstorf 's former PhD student #Caesar 2018.
If you recall, that's the latitude in the S-Atlantic that #vanWesten etal 2024 found as prime location for early warning signal of an imminent AMOC collapse in their freshwater experiment.

By applying melt (but without the observed AND projected acceleration that #Greene et al 2024 notify us of https://www.nature.com/articles/s41586-023-06863-2 ), Pontes' model now projects a total slowdown of 30% by 2040.
(Also noteworthy maybe that the authors pull the 2degree milestone forward to 2040, while some papers I read in 2018 still saw 2C sometime in the 2050s. But they're not the first researchers doing so that I came across.)

Meltrate in Greenland is 30Mt of ice per hour... Did you know that 1kg of pizza equals 19kg CO2 which ultimately melts 12.3 t glacial ice?
1 cup of coffee is 400gr CO2 and melts 260 kg. (sources see #2)

Meanwhile, #COP29 news falsely report a global consensus in coal phase-out. A journalist on Bluesky dug into the actual agreement and the countries listed.
First, it's not a global agreement.
Then either, the countries have no coal energy, or they have already long ago planned the phaseout so nothing new from them, either.
The single country with a new development in this coal agreement is Australia which announced to close 3 coal power plants ... sometime in the future...

ARTENSTERBEN - im Gange

BETROFFEN - Menschheit

STATUS - beginnender Exodus

true or false?

Hoffnung?

YOUTUBE Video Vortrag

Prof. Stefan #Rahmstorf zur öffentlichen #Klimadebatte

#EarthSystemAnalysis - #PotsdamInstitute

#Klimageschichten #Zukunftsliebe #Kinderkraft #Seelenheil #Angstfreiheit

#Lebendürfen #Cop29

🙏 https://youtu.be/UOyCiL5LPic 👯

#Bayern #klimakatastrophe #Zeitgeschichte wird bewegt geschrieben #Zeitgeschehen #Hanfgeschichten #Klimaschutz #forfuture

Bildschirmfoto YOUTUBE Video Vortrag

Prof. Stefan Rahmstorf zur öffentlichen Klimadebatte

Earth System Analysis - Potsdam Institute
7990 Abonnenten

Am 15.3.2019 hatte die #AfD bei einer #FridaysForFuture Demo an Schüler einen Klimaquiz verteilt. Harald Lesch sprach mit dem #Klimaforscher Prof. Stefan #Rahmstorf über den Klimaquiz. #Klimakrise #Klimaschutz

https://www.youtube.com/watch?v=pxLx_Y6xkPQ

Am 15.3.2019 hat die #NoAfD bei einer #FridaysForFuture Demo an Schüler einen Klimaquiz verteilt. Harald Lesch spricht mit dem #Klimaforscher Prof. Stefan #Rahmstorf über die richtigen Antworten. #Klimakrise #Klimaschutz

https://www.youtube.com/watch?v=pxLx_Y6xkPQ

EL PAÍS #AMOC #amoccollapse #amoclauf #rahmstorf
https://elpais.com/clima-y-medio-ambiente/2024-11-09/stefan-rahmstorf-climatologo-el-colapso-de-la-corriente-oceanica-atlantica-provocaria-un-clima-extremo-sin-precedentes-en-europa.html

Trouble is brewing in the North Atlantic.

'We don't really consider it low probability anymore':

Collapse of key Atlantic current could have catastrophic impacts, says oceanographer Stefan Rahmstorf

The Atlantic Ocean's most vital ocean current is showing troubling signs of reaching a disastrous tipping point.

Oceanographer Stefan Rahmstorf tells Live Science what the impacts could be.

Beneath the waves, the Atlantic Meridional Overturning Circulation ( #AMOC ),
which includes the Gulf Stream,
acts as a planetary conveyor belt bringing nutrients, oxygen and heat north from tropical waters,
while moving colder water south
— a balancing act that keeps the Northern Hemisphere warm.

But research into Earth's climate history shows that the current has switched off in the past,
and a growing number of studies suggest that climate change is causing the AMOC to slow, possibly leading it toward a disastrous collapse.

On Monday (Oct. 21), 44 oceanographers from 15 countries published an open letter calling for urgent action in the face of the weakening circulation.
They warn that the risk of collapse has been "greatly underestimated" and will have "devastating and irreversible impacts" for the world.

Live Science sat down with the letter's lead organizer, #Stefan #Rahmstorf, an oceanographer who runs the Earth system analysis department at the Potsdam Institute for Climate Impact Research in Germany, to discuss the AMOC developments and their potential global effects.

https://www.livescience.com/planet-earth/rivers-oceans/we-dont-really-consider-it-low-probability-anymore-collapse-of-key-atlantic-current-could-have-catastrophic-impacts-says-oceanographer-stefan-rahmstorf

Brand new 52min documentary on #ClimateTippingPoints with
#Rockström, #Rahmstorf, @weatherwest #Swain and a few others.
https://www.youtube.com/watch?v=U8pLrRkqbb0

The scientists speak a little into the camera, then the filmmaker either illustrates the spoken words with aerial nature scenes or with clear, animated graphics.
English with English subtitles. I like it!

Again, the 7%-water-rule comes up.
Eye opener: 7% at +1.5C is more water vapour than what 7% was at +1C. Same principle as in how the rich get richer faster.

Not answered: most land mass has more than +1C, Germany in summer can be +3C, places in the Adriatic sea +5C this August.
So do we apply the 7%-rule to the local deviation from the normal in order to express or to guage the water hunger of the air in this particular parcel?
And also, what happens when the wind drives one parcel away after it drank its fill from soil, plants, water bodies, and a new parcel comes in, heats up to the local deviation, drinks its fill, and moves. I mean, shouldn't the inner continents be all dried up by now?
Or maybe the act of evaporation cools the place enough for a new parcel that moves in, to be sufficiently shocked into raining down what it had sucked up elsewhere...hm.
Anyway. Good documentary!

https://www.theguardian.com/environment/2024/oct/23/we-dont-know-where-the-tipping-point-is-climate-expert-on-potential-collapse-of-atlantic-circulation

An interview by #JonathanWatts with #Rahmstorf on his assessment of the AMOC situation.

Nothing new if you follow Rahmstorf. But I'd like to point out this bit: " Some colleagues say we shouldn’t talk about extreme possibilities like an Amoc collapse because it sounds alarmist and might distract people from more certain impacts of global heating "
because it is reminiscent of the outrageous NYTimes event 4 weeks ago where David Wallace-Wells had Rahmstorf on stage with Michael Oppenheimer.
Oppenheimer is an anti-alarmist. And acc to his Wiki article, he shaped the US interface between politics and science since the acid rain issue. Interface = read "filter".

So he is a major reason why the US has not done anything in the past 30 years. And due to huge influence on multi-state bodies like OECD, G7, IMF, World Bank, Oppenheimer is also co-responsible for their failure.

On stage, Oppenheimer said exactly that which Rahmstorf alludes to in the Guardian interview: "Let's not talk about AMOC at all. No politician can hang his hat on those uncertainties. Let's focus adaptation instead!"

Oppenheimer was not corrected by Wallace-Wells. Typical NYTImes failure.
But what do you suggest to adapt to, Oppenheimer? A warming world, a super-heating world, or one with a collapsed AMOC?
And do politicians "hang their hat on" nuclear plants or bridges being built with a 50% risk of a major catastrophe?

Arrogant, smug Dunning-Kruger ass. <shudders>

I feel, the interview in the Guardian is a direct response to that event.
But it isn't really. The interview is part of the news cycle of the letter from 44 Scientists to the governments of the #ArcticCouncil .

I posted about the NYTimes event in the previous toots ⤴️

Guter Podcast zum Cold Blob und AMOC https://www.ardaudiothek.de/episode/iq-wissenschaft-und-forschung/raetselhafte-kaelteblase-geraet-der-subpolarwirbel-aus-dem-takt/bayern-2/13795411/

Mit #Rahmstorf, eh klar, aber noch eine Forscherin ist dabei, die speziell Interessantes erzählt.

Hab wieder was dazu gelernt.
Zum Beispiel ziemlich am Anfang, zum Subpolaren Wirbel, wie der überhaupt entsteht.
Durch Wind!
Der treibt das warme Golfstromwasser auf der Höhe New Yorks nach Osten. Und dort gibt es dann irgendwo so eine Art Kreuzung, wo der Wind nach Norden oder weiter nach Osten geht.
Wenn er nach Norden geht, treibt er damit auch den Wirbel an.
Und dann weht er auch mal vo Ost nach West... im Winter wohl..

Im Filmchen sieht man die v-Wind Komponente in den Wintermonaten. V-Wind ist rot, wenn der Wind nach Norden weht. Und blau, wenn er nach Süden weht. Daten: https://climatereanalyzer.org/research_tools/monthly_maps/

Der Subpolar Gyre / Cold Blob ist auch nich immer an derselben Stelle, fest eingemauert oder so. Nee! Das wabert alles so fuzzy rum, mal mehr rechts und mal mehr links.
Und je nachdem ob mehr rechts oder mehr links, gibt es in Zentraleuropa starke Hitze.

Muss auch gucken, dass ich ein paper von ihr finde. Vll steht ja in der "Introduction" noch mehr Interessantes um Subpolar Gyre drin.

#AMOC #ColdBlob #SPG #SubpolarGyre

2 weeks ago, #Rahmstorf and Michael Oppenheimer were asked a few questions on stage by David Wallace-Wells .

https://www.youtube.com/watch?v=cJ1GVMWzWIE

In the drawers in my mind, David sits in the rich_doomer category, someone who warmly wallows in fearporn. I'm probably wrong, tho. It's just the drawers that I have in my mind. Constantly changing.

Michael? Never heard of the guy. Apparently, he shaped the connection science_politics in US (and allied?) regarding climate and acid rain.
Seeing where US went since climate became an issue (nowhere), Michael probably is/was an anti-alarmist, in bed with economists of the Nordhaus persuasion.

I hadn't looked him up on Wiki before watching.

What made me crabby was his argument that one shouldn't focus on tipping points at all. And then quotes from a study from 3 years ago which put AMOC tipping at 1.5 to 8°C warming –
to illustrate how irrelevant we should deem it. (Rahmstorf put the record straight – before Michael got the mic.)

After telling us how irrelevant AMOC tipping is due to its uncertainty – "How can any politician hang his hat on such uncertainties, I ask?" –
M. then says, we should pour all our money and attention in adaptation. And emission reduction, as an afterthought.

Only when I let go of my anger at this old white guy, I can see how he has a point. Our societal infrastructure and ofc also the hardware is not ready to receive the mounting and compounding climate extremes without getting seriously destabilised.

Nothing has been done before Greta came along. Nothing.

But how he presents his arguments – and how he thinks wrt tipping elements (even denies that most of the 16 defined elements were such) – is outrageous.

And now that I skim-read the first paragraph in his Wiki article, I can see why we are where we are, if this guy shaped the interface science_politics in the US, in G7 and OECD.

That nothing has been done this far is his success story. And now he prioritizes adaptation.

And ignores the illogic in his assessment: that there is up to now, and thanks to him, no yardstick for what level of #climatechange we should adapt to. Let alone what we should do regarding adaption for a looming AMOC tipping.

Rahmstorf gets the mic again at the end and points that one out: do you adapt to a warming world or do you adapt to an AMOC tipping?

If AMOC tips, the Southern hemisphere warms by an additional 1 - 2C. That means on land 2 to 4C on top of what's in the pipeline.

Grmpf.
I'd really like to know why David or the NYT invited Michael for this event. If they wanted to show us how badly Michael shaped science_politics – mission accomplished. But this interpretation is left to the viewer. And I very much doubt that people dare to criticise such an old climate scientist. So they're left with: @rahmstorf is an alarmist and Michael is the go-to person who really gets it all.
<smh>

#NYTimes #NYTimesEvent
#NYClimateWeek