Johannes Quaas
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jquaas.bsky.social
Johannes Quaas
@jquaas.bsky.social
Theoretical Meteorology, Leipzig University
Clouds and climate, biodiversity and climate, aerosols and clouds
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
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
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
By the way, Timo presented their nice paper demonstrating that climate attribution has the potential to change people's attitudes, and that people are even willing to pay for it: www.journals.uchicago.edu/doi/10.1086/...
September 4, 2025 at 1:58 PM
September 4, 2025 at 9:06 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!
September 4, 2025 at 9:03 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...
August 28, 2025 at 8:15 AM
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
Congratulations and kudos to the citizens of Paris for once again leading in improving quality of life, safety, air quality, creating niches for #biodiversity and adapting to #climatechange! There is a street near where we have the privilege to live for a few months. A role model for other cities!
March 25, 2025 at 8:21 AM
March 7, 2025 at 12:58 PM
Webinar series following the Evidence review report on Solar radiation modification for the European Commission, open to everyone:
23 Jan, 15 CET. scientificadvice.eu/events/solar...
3 Feb, 15 CET. scientificadvice.eu/events/solar...
11 Mar, 14 CET. scientificadvice.eu/events/solar...
January 13, 2025 at 10:13 AM
Satellite measurements are very useful tools to learn about how clouds act in climate change. The interpretation requires inverse radiative transfer calculations. PhD researcher Jessenia Gonzalez now used machine learning to make this much faster. Excellent collaboration with @isp-uv-es.bsky.social
December 19, 2024 at 7:18 AM
As the debate around solar radiation modification (SRM; aka geoengineering) intensifies, the European Commission asked about an evidence review report. Bottom line: SRM is no meaningful option to combat climate change. The debate helps to sharpen arguments. scientificadvice.eu/advice/solar...
December 9, 2024 at 3:13 PM
Climate change and biodiversity loss are connected! This week we presented our ideas for a collaborative project to our national funding agency. Fingers crossed, we will know the outcome in May
December 7, 2024 at 7:53 AM
Super Erfolg, voller Saal in der Albertina 👏
November 11, 2024 at 4:57 PM
When we emit gases or particles to the atmosphere, at short timescale it adjusts, for example the clouds. This may amplify or dampen the the Earth energy balance.
New overview paper now out in AGU Advances from our CONSTRAIN EU project
October 16, 2024 at 1:17 PM