Johannes Quaas
@jquaas.bsky.social
Theoretical Meteorology, Leipzig University
Clouds and climate, biodiversity and climate, aerosols and clouds
Clouds and climate, biodiversity and climate, aerosols and clouds
Dokumentation über Klima und Amazonas mit der super Kollegin Mira Pöhlker @tropos-de.bsky.social @meteoleipzig.bsky.social
Nicht verpassen! Heute 19:25 im #ZDF & online:
#Expedition #Amazonas mit #ATTO & der #Leipzig-er #Wolken-Forscherin Mira Pöhlker (#TROPOS) > www.zdf.de/video/dokus/...
#COP30 #Brazil @zdfde.bsky.social #Klimawandel #ATTOproject @mpic.de #MPI_BGC @leibniz-gemeinschaft.de @unileipzig.bsky.social
#Expedition #Amazonas mit #ATTO & der #Leipzig-er #Wolken-Forscherin Mira Pöhlker (#TROPOS) > www.zdf.de/video/dokus/...
#COP30 #Brazil @zdfde.bsky.social #Klimawandel #ATTOproject @mpic.de #MPI_BGC @leibniz-gemeinschaft.de @unileipzig.bsky.social
November 10, 2025 at 9:19 PM
Dokumentation über Klima und Amazonas mit der super Kollegin Mira Pöhlker @tropos-de.bsky.social @meteoleipzig.bsky.social
A joint job offer is open for Junior Professorship Financial Economics
@unileipzig.bsky.social together with the excellent @iwh-halle.bsky.social
Really interesting focus on sustainability, links to biodiversity and climate:
www.uni-leipzig.de/en/universit...
@unileipzig.bsky.social together with the excellent @iwh-halle.bsky.social
Really interesting focus on sustainability, links to biodiversity and climate:
www.uni-leipzig.de/en/universit...
Junior Professorship in VWL, esp. Financial Economics (W1)
www.uni-leipzig.de
November 10, 2025 at 10:17 AM
A joint job offer is open for Junior Professorship Financial Economics
@unileipzig.bsky.social together with the excellent @iwh-halle.bsky.social
Really interesting focus on sustainability, links to biodiversity and climate:
www.uni-leipzig.de/en/universit...
@unileipzig.bsky.social together with the excellent @iwh-halle.bsky.social
Really interesting focus on sustainability, links to biodiversity and climate:
www.uni-leipzig.de/en/universit...
Reposted by Johannes Quaas
It was a call I couldn't ignore.
I was formally invited by the Danish EU Presidency to Luxembourg to speak about industrial electrification and energy efficiency directly to the energy ministers from every single one of the 27 EU member states on the 20th of October.
www.youtube.com/watch?v=FO30...
I was formally invited by the Danish EU Presidency to Luxembourg to speak about industrial electrification and energy efficiency directly to the energy ministers from every single one of the 27 EU member states on the 20th of October.
www.youtube.com/watch?v=FO30...
Speaking at EU Energy Council
YouTube video by Jan Rosenow
www.youtube.com
October 20, 2025 at 11:10 AM
It was a call I couldn't ignore.
I was formally invited by the Danish EU Presidency to Luxembourg to speak about industrial electrification and energy efficiency directly to the energy ministers from every single one of the 27 EU member states on the 20th of October.
www.youtube.com/watch?v=FO30...
I was formally invited by the Danish EU Presidency to Luxembourg to speak about industrial electrification and energy efficiency directly to the energy ministers from every single one of the 27 EU member states on the 20th of October.
www.youtube.com/watch?v=FO30...
Reposted by Johannes Quaas
Last week the German Meteorological Society warned that "the 3-degree limit could be exceeded as early as 2050".
While not possible to fully rule out, the assessed warming scenarios we published in the IPCC AR6 report find this to be extremely unlikely.
While not possible to fully rule out, the assessed warming scenarios we published in the IPCC AR6 report find this to be extremely unlikely.
September 28, 2025 at 8:47 PM
Last week the German Meteorological Society warned that "the 3-degree limit could be exceeded as early as 2050".
While not possible to fully rule out, the assessed warming scenarios we published in the IPCC AR6 report find this to be extremely unlikely.
While not possible to fully rule out, the assessed warming scenarios we published in the IPCC AR6 report find this to be extremely unlikely.
That's really great, congratulations! And I'm happy my colleague Made Maahn @meteoleipzig.bsky.social helps make it happen!
It's official: WIVERN will be ESA's 11th Earth Explorer satellite, measuring winds deep inside hurricanes, fronts and other weather systems!
www.esa.int/Applications...
www.esa.int/Applications...
ESA selects WIVERN as 11th Earth Explorer mission
After meticulous preparation and rigorous evaluation, ESA’s Member States have selected WIVERN to become the 11th Earth Explorer mission to be implemented through the agency’s prestigious FutureEO pro...
www.esa.int
September 27, 2025 at 4:29 AM
That's really great, congratulations! And I'm happy my colleague Made Maahn @meteoleipzig.bsky.social helps make it happen!
The national project "WarmWorld" works on the new-generation global climate simulations at resolutions as high as 1 km. At @kit.edu a group of us met to discuss how to represent the cloud processes in clouds in such computationally-demanding models, to account for pollution effects on climate.
September 26, 2025 at 2:59 PM
The national project "WarmWorld" works on the new-generation global climate simulations at resolutions as high as 1 km. At @kit.edu a group of us met to discuss how to represent the cloud processes in clouds in such computationally-demanding models, to account for pollution effects on climate.
Currently at the annual meeting of the "Arctic amplification" collaborative research project. Discussion on how increases in convection in the Arctic make it more "tropical" with warming. ac3-tr.de funded by @dfg.de, partners @meteoleipzig.bsky.social, U Bremen, Köln, @awi.de, @tropos-de.bsky.social
September 24, 2025 at 4:55 PM
Currently at the annual meeting of the "Arctic amplification" collaborative research project. Discussion on how increases in convection in the Arctic make it more "tropical" with warming. ac3-tr.de funded by @dfg.de, partners @meteoleipzig.bsky.social, U Bremen, Köln, @awi.de, @tropos-de.bsky.social
Reposted by Johannes Quaas
In a UN speech today, President Trump said that "all of these [climate] predictions were wrong".
Back in 2019 I led a research effort to digitize old climate model projections and assess how well they did. Turns out they got future warming pretty spot on!
Back in 2019 I led a research effort to digitize old climate model projections and assess how well they did. Turns out they got future warming pretty spot on!
September 23, 2025 at 5:01 PM
In a UN speech today, President Trump said that "all of these [climate] predictions were wrong".
Back in 2019 I led a research effort to digitize old climate model projections and assess how well they did. Turns out they got future warming pretty spot on!
Back in 2019 I led a research effort to digitize old climate model projections and assess how well they did. Turns out they got future warming pretty spot on!
Since one year, the Research Training Group "Economics of connected natural commons" studies the challenges of sustainably using ecosystems and the climate system as commons. We just come back from the first retreat between the 14 PhD candidates, advisers, and excellent invited external speakers.
September 12, 2025 at 6:57 PM
Since one year, the Research Training Group "Economics of connected natural commons" studies the challenges of sustainably using ecosystems and the climate system as commons. We just come back from the first retreat between the 14 PhD candidates, advisers, and excellent invited external speakers.
The current Advanced Training Module on "Climate Attribution", joinly by our interdisciplinary research training group "Economics of Connected Natural Commons" and the Leipzig Graduate school on Clouds, aerosols and radiation sparked large interest: 65 PhD researchers from 7 countries!
September 4, 2025 at 9:03 AM
The current Advanced Training Module on "Climate Attribution", joinly by our interdisciplinary research training group "Economics of Connected Natural Commons" and the Leipzig Graduate school on Clouds, aerosols and radiation sparked large interest: 65 PhD researchers from 7 countries!
Great piece from Nadir Jeevanjee. As a meteorologist I of course love it when forecasts prove correct but as a citizen I would have preferred it if climate change had been prevented on the basis of the forecasts
nice article from Nadir Jeevanjee (is he on bluesky?) about predictions climate models got right. successful predictions are the gold standard of science.
5 forecasts early climate models got right – the evidence is all around you
theconversation.com/5-forecasts-...
5 forecasts early climate models got right – the evidence is all around you
theconversation.com/5-forecasts-...
5 forecasts early climate models got right – the evidence is all around you
From rising global temperatures to the fast-warming Arctic, early climate models predicted the changes half a century ago.
theconversation.com
September 4, 2025 at 5:18 AM
Great piece from Nadir Jeevanjee. As a meteorologist I of course love it when forecasts prove correct but as a citizen I would have preferred it if climate change had been prevented on the basis of the forecasts
Cloud drop number is a key quantity to understand cloud processes. Getting it from satellites so far was very indirect. Gonzalez et al. @meteoleipzig.bsky.social @scadsai.bsky.social now created a machine-learning method to get it directly from satellite radiances ieeexplore.ieee.org/document/111...
August 28, 2025 at 8:15 AM
Cloud drop number is a key quantity to understand cloud processes. Getting it from satellites so far was very indirect. Gonzalez et al. @meteoleipzig.bsky.social @scadsai.bsky.social now created a machine-learning method to get it directly from satellite radiances ieeexplore.ieee.org/document/111...
I'm glad to contribute again!
The #IPCC has announced the authors selected for its Seventh Assessment Report.
664 experts from 111 countries have been invited to participate as Coordinating Lead Authors, Lead Authors, & Review Editors.
🌍 51% from developing countries
🚺 46% women
🔗 bit.ly/AR7AuthorsPR
664 experts from 111 countries have been invited to participate as Coordinating Lead Authors, Lead Authors, & Review Editors.
🌍 51% from developing countries
🚺 46% women
🔗 bit.ly/AR7AuthorsPR
August 18, 2025 at 9:19 PM
I'm glad to contribute again!
Reposted by Johannes Quaas
Imagine all cars were electric, and then one Volkswagen engineer comes up with another idea …
#EMobility
#EMobility
August 11, 2025 at 10:46 AM
Imagine all cars were electric, and then one Volkswagen engineer comes up with another idea …
#EMobility
#EMobility
How does cloud drop size distribution respond to aerosol? Hengqi Wang, visiting PhD researcher from Tsinghua university, used new data from satellite measurements of polarization from SRON/Netherlands to quantify the effect. Offsets systematically 7% of the aerosol-cloud forcing. rdcu.be/ezaeX
August 4, 2025 at 1:27 PM
How does cloud drop size distribution respond to aerosol? Hengqi Wang, visiting PhD researcher from Tsinghua university, used new data from satellite measurements of polarization from SRON/Netherlands to quantify the effect. Offsets systematically 7% of the aerosol-cloud forcing. rdcu.be/ezaeX
Reposted by Johannes Quaas
As @pkrugman.bsky.social writes, this is a deliberate effort to destroy science.
For MAGA, Ignorance is Strength
Research cuts aren’t about shrinking government, they’re about killing science
paulkrugman.substack.com
July 16, 2025 at 4:53 AM
As @pkrugman.bsky.social writes, this is a deliberate effort to destroy science.
Übersicht zum Thema Aerosole und Klima, gemeinsam mit Mira Pöhlker @tropos-de.bsky.social , deutschsprachig, an physik-interessierte Leserschaft gerichtet:
Bessere Luftqualität erwärmt die Erde: Aerosole und Klima - Quaas - Physik in unserer Zeit onlinelibrary.wiley.com/doi/10.1002/...
Bessere Luftqualität erwärmt die Erde: Aerosole und Klima - Quaas - Physik in unserer Zeit onlinelibrary.wiley.com/doi/10.1002/...
Bessere Luftqualität erwärmt die Erde: Aerosole und Klima
Aerosolpartikel in der Atmosphäre wirken kühlend auf das Klima, weil sie Sonnenlicht reflektieren und auch Wolken mehr reflektieren lassen. Eine Verbesserung der Luftqualität wirkt deswegen, relativ ...
onlinelibrary.wiley.com
June 24, 2025 at 6:12 PM
Übersicht zum Thema Aerosole und Klima, gemeinsam mit Mira Pöhlker @tropos-de.bsky.social , deutschsprachig, an physik-interessierte Leserschaft gerichtet:
Bessere Luftqualität erwärmt die Erde: Aerosole und Klima - Quaas - Physik in unserer Zeit onlinelibrary.wiley.com/doi/10.1002/...
Bessere Luftqualität erwärmt die Erde: Aerosole und Klima - Quaas - Physik in unserer Zeit onlinelibrary.wiley.com/doi/10.1002/...
Reposted by Johannes Quaas
We have a PhD position in Meteorology open at the University of Bergen. Join us to study the moisture transport in extratropical cyclone families using reanalysis data, water tracer simulations, and stable water isotopes. Application deadline 24 June 2025: www.jobbnorge.no/en/available...
PhD Research Fellow in Meteorology (281744) | University of Bergen
Job title: PhD Research Fellow in Meteorology (281744), Employer: University of Bergen, Deadline: Tuesday, June 24, 2025
www.jobbnorge.no
June 6, 2025 at 4:27 PM
We have a PhD position in Meteorology open at the University of Bergen. Join us to study the moisture transport in extratropical cyclone families using reanalysis data, water tracer simulations, and stable water isotopes. Application deadline 24 June 2025: www.jobbnorge.no/en/available...
Reposted by Johannes Quaas
This is great! And yes we should f***ing swear more about how we are still neither reducing global emissions to meet agreed targets nor adapting to increasing extreme weather already now happening
US climate scientists need all the help they can get. Including from foul-mouthed comedians! 🤡😱😱
Watch Emmy Award-Winning David Cross team up with Prof Michael Oppenheimer in the US launch of the hit series "Climate Science Translated".
#climate #arresteddevelopment #climatescience
Watch Emmy Award-Winning David Cross team up with Prof Michael Oppenheimer in the US launch of the hit series "Climate Science Translated".
#climate #arresteddevelopment #climatescience
June 3, 2025 at 11:02 AM
This is great! And yes we should f***ing swear more about how we are still neither reducing global emissions to meet agreed targets nor adapting to increasing extreme weather already now happening
Reposted by Johannes Quaas
The people telling you climate change isn’t real would also like you to believe that paying rent on an empty building saves money
www.nytimes.com/2025/05/16/n...
www.nytimes.com/2025/05/16/n...
NASA Office Above ‘Seinfeld’ Diner Is a Target of Trump Budget Shrinkage
www.nytimes.com
May 16, 2025 at 11:28 AM
The people telling you climate change isn’t real would also like you to believe that paying rent on an empty building saves money
www.nytimes.com/2025/05/16/n...
www.nytimes.com/2025/05/16/n...
Reposted by Johannes Quaas
We will have talks from @andrewdessler.com, @drkatemarvel.bsky.social, @johnmoralestv.bsky.social, Kerry Emanuel, Bernadette Woods Placky, Ralph Keeling, Ben Santer, and many more! Sign up and learn more at wclivestream.com
The Weather & Climate Livestream
Join us starting May 28th, as meteorologists and climate scientists from across the US share their research and answer your questions.
wclivestream.com
May 14, 2025 at 10:14 PM
We will have talks from @andrewdessler.com, @drkatemarvel.bsky.social, @johnmoralestv.bsky.social, Kerry Emanuel, Bernadette Woods Placky, Ralph Keeling, Ben Santer, and many more! Sign up and learn more at wclivestream.com
Reposted by Johannes Quaas
Hommage aux chercheurs de l'Agence américaine d'observation océanique et atmosphérique (NOAA), licenciés en 2025 sous l’administration Trump. Merci pour votre travail en sciences du climat, votre engagement, vos découvertes.
#StandUpForScience
#StandUpForScience
Dear NOAA: Thank You
YouTube video by Cole Vaughn
youtu.be
May 1, 2025 at 7:23 AM
Hommage aux chercheurs de l'Agence américaine d'observation océanique et atmosphérique (NOAA), licenciés en 2025 sous l’administration Trump. Merci pour votre travail en sciences du climat, votre engagement, vos découvertes.
#StandUpForScience
#StandUpForScience
Yes science is done by people not buildings but this should be halted. The enormous scientific success of GISS is not least thanks to its proximity to Columbia University, and the fantastic discussions in the seminar rooms on 2880 Broadway. I learned so much during stimulating research stays.
The Trump administration has canceled the lease for NASA's top climate science modeling and monitoring lab, known as NASA GISS, at Columbia Univ. in NYC. The lab is going virtual as of May 31. (The lab is above the Seinfeld restaurant.) www.cnn.com/2025/04/24/c...
Trump administration cancels top NASA climate lab’s lease at Columbia University | CNN
The NASA lab tracks global climate conditions, serving as one of the main centers worldwide for this information.
www.cnn.com
April 25, 2025 at 6:31 AM
Yes science is done by people not buildings but this should be halted. The enormous scientific success of GISS is not least thanks to its proximity to Columbia University, and the fantastic discussions in the seminar rooms on 2880 Broadway. I learned so much during stimulating research stays.
"misaligned with the President’s agenda" if you have few years to live and no other person is of interest to you, in particular not future generations.
GFDL anticipates what is coming, with so many smart and brave scientists. We in Europe stand in solidarity with our colleagues and friends.
GFDL anticipates what is coming, with so many smart and brave scientists. We in Europe stand in solidarity with our colleagues and friends.
"The possible elimination of the lab, called GFDL, in concert with potential cuts to other NOAA operations, threatens irreparable harm not only to global understanding of climate change and long-range scenarios for the planet but to the country’s safety, competitiveness and national security."
White House Proposal Could Gut Climate Modeling the World Depends On
Potential funding cuts for NOAA and its research partners threaten irreparable harm not only to climate research but to American safety, competitiveness, and national security.
www.propublica.org
April 25, 2025 at 6:28 AM
"misaligned with the President’s agenda" if you have few years to live and no other person is of interest to you, in particular not future generations.
GFDL anticipates what is coming, with so many smart and brave scientists. We in Europe stand in solidarity with our colleagues and friends.
GFDL anticipates what is coming, with so many smart and brave scientists. We in Europe stand in solidarity with our colleagues and friends.