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Reposted by Emanuele Bevacqua

Jakob Zscheischler @zscheischlerjak.bsky.social · Aug 29

Our new study on how large floods will change in Europe under climate change, led by @bfang.bsky.social, with @bevacquae.bsky.social

Communications Earth & Environment @commsearth.nature.com · Aug 29

❄️🌧️Reduced snowmelt dominates changes in Northern Europe's largest floods, while heavy precipitation dominates Western Europe flood events.

@bfang.bsky.social @zscheischlerjak.bsky.social

👉Read more here:
www.nature.com/articles/s43...

Diverging trends in large floods across Europe in a warming climate - Communications Earth & Environment

Reduced snowmelt dominates northern Europe’s largest floods variation while heavy precipitation dominates western Europe flood events, according to a joint assessment of changes in the timing, spatial...

www.nature.com

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Emanuele Bevacqua @bevacquae.bsky.social · Jul 16

Indeed, it was a pleasure to contribute to this course with content on extreme events, climate change, and attribution science. Now it’s time for the examination! :)

Larisa Tarasova @lytarasova.bsky.social · Jul 15

Today marks the end of my first teaching semester @unileipzig.bsky.social 📚🤩 it was a great experience to get to know such a great batch of students! Special thanks to my co-lecturer @bevacquae.bsky.social for the support 💪🏽

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Reposted by Emanuele Bevacqua

sifangfeng.bsky.social @sifangfeng.bsky.social · Apr 28

To what extent does human-induced climate change contribute to global extreme wildfires? In our latest study, we quantified the contribution of human-induced climate change to over 700 observed extreme wildfires globally. www.nature.com/articles/s41...

Growing human-induced climate change fingerprint in regional weekly fire extremes - npj Climate and Atmospheric Science

npj Climate and Atmospheric Science - Growing human-induced climate change fingerprint in regional weekly fire extremes

www.nature.com

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Emanuele Bevacqua @bevacquae.bsky.social · May 5

📊 Warming was the main driver, but precipitation, humidity, and wind changes either enhanced or counteracted warming effects in many regions.

📄 Paper in npj Climate and Atmospheric Science www.nature.com/articles/s41... or rdcu.be/eiYcp

@natureportfolio.nature.com @compoundnet.bsky.social

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Emanuele Bevacqua @bevacquae.bsky.social · May 5

🔥🌍 In a new paper led by Sifang Feng, we find a growing human-induced climate change fingerprint in weekly regional fire extremes.

📈 On average, climate change was responsible for a fraction equal to 8 ± 4% of the predicted probability of more than 700 fire extremes worldwide between 2002 and 2015.

Growing human-induced climate change fingerprint in regional weekly fire extremes - npj Climate and Atmospheric Science

npj Climate and Atmospheric Science - Growing human-induced climate change fingerprint in regional weekly fire extremes

www.nature.com

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Reposted by Emanuele Bevacqua

Zack Labe @zacklabe.com · Mar 5

Hi - I'd like to share this story of what is happening at NOAA GFDL, where some of my colleagues and I worked until the mass firings at NOAA last week.

"...the birthplace of weather and climate forecasting"

NOAA firings hit the birthplace of weather and climate forecasting

Dismissed researchers were improving severe weather predictions

www.science.org

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 24

Great job opportunity in Graz, check it out!

Douglas Maraun @dmaraun.bsky.social · Feb 24

Like to develop your own research profile? Work on a permanent contract in a diverse, inspiring & supportive work environment?
We seek to appoint a scientist working on climate hazards for risk assessments & on data management & analysis. Join us at Wegener Center:

jobs.uni-graz.at/en/jobs/6015...

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 12

Hi Glen, adding to Carl, more text related to this is in paragraphs 2-3 of our brief communication. For those interested in expanding, see also Betts' discussion: www.nature.com/articles/d41.... The same windows are also used to document impacts/effects emerging at a given warming level.

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Reposted by Emanuele Bevacqua

New Scientist @newscientist.com · Feb 10

2024 was the first year to see global average temperatures rise more than 1.5°C above pre-industrial levels. Has the Paris Agreement goal already bitten the dust? www.newscientist.com/article/2467...

Have we already breached the 1.5°C global warming target?

Although the climate goals set by the Paris Agreement are based on the long-term average temperature, one year of high temperatures might be a sign that the 1.5°C threshold has already been reached

www.newscientist.com

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Reposted by Emanuele Bevacqua

Nature Portfolio @natureportfolio.nature.com · Feb 10

Two papers in Nature Climate Change suggest that exceeding 1.5 °C in 2024 may indicate that we have entered a multi-decadal period of 1.5 °C average global warming.
https://go.nature.com/4hR9GYO
https://go.nature.com/3WVdJM1
🧪

This is figure 2 from “A year above 1.5 °C signals that Earth is most probably within the 20-year period that will reach the Paris Agreement limit.” It shows strong warming trends place the first 1.5 °C year within the 1.5 °C 20-year period.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

The results in both papers depend on how CMIP6 models capture relevant climate processes over the next decade or so. See Discussion and bsky.app/profile/clim...

Work @ufz.de together with @carlschleussner.bsky.social and @zscheischlerjak.bsky.social

Climate Analytics @climateanalytics.org · Feb 10

Paper no1 by @bevacquae.bsky.social and colleagues asks what a year where average annual global warming is at or above 1.5°C tells us about the timing of reaching or exceeding the Paris Agreement's longer-term 1.5°C limit.

The 2024 calendar year was the first such year.

A year above 1.5 °C signals that Earth is most probably within the 20-year period that will reach the Paris Agreement limit - Nature Climate Change

What a first year with temperature 1.5 °C above the pre-industrial baseline implies for long-term temperature goals is unclear. Here the authors show that such a first year above the baseline is highl...

doi.org

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

In contrast, while our results are more conservative by indicating we are in the first part of the 20-year period and not that the goal has been breached, they rely on the occurrence of a calendar year above 1.5°C, which is supported by the average of multiple observational datasets (1.55°C).

Earth breaches 1.5 °C climate limit for the first time: what does it mean?

The threshold has been exceeded for only one year so far, but humanity is nearing the end of what many thought was a ‘safe zone’ as climate change worsens.

www.nature.com

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Making their result actionable requires the occurrence of 12 consecutive months above 1.5°C, a condition met in ERA5 and BEST observational datasets, but that has not been met based on the mean of multiple observational datasets (plot for consecutive months strictly > 1.5°C by @hoegner.bsky.social).

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

An extra note is needed to help link our results with another study published by Cannon today. In climate models (SSP245), Cannon found a 76% chance that 12 consecutive months above 1.5°C occur *after* the Paris Agreement goal is reached, that is, after the midpoint of a 20-year window at 1.5°C.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Finally, we highlight that the entry time in the 20-year period at 1.5 °C warming should not be mistaken as the timing of the warming level itself, as the latter is placed at the midpoint of the 20-year period.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Only rapid near-term mitigation can effectively limit peak warming, which is required to hold warming *well below* 2 °C in case of exceedance or overshoot of 1.5 °C. www.nature.com/articles/s43...

A year above 1.5 °C is not the time for despair but a call to action.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Cutting emissions has never been more important. It can lower the chance of reaching the 1.5°C limit soon after 2024, but this demands very stringent mitigation. For example, halving the chance that 2024 will be within the first 20-yr 1.5°C period requires a fivefold reduction in temperature trends.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

The IPCC AR6 flags “High Risks” at 1.5°C for unique systems (such as biodiversity) and extreme events. Floods in Brazil, Spain, and Kenya, mega-drought in the Amazon, tropical storms, and heatwaves in 2024 gave us a taste of these risks. We are not prepared for the climate risks at 1.5°C to unfold.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Entering a window at 1.5 °C average warming means entering the same window used by scientists to project the impacts of a 1.5 °C warmer world. Thus, our results warn we are most probably in a period where the impacts of a 1.5 °C world are expected to unfold, underscoring the urgency of adaptations.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Our result is due to the ongoing strong anthropogenic multi-decadal warming trend that, combined with the relatively low variability in the temperature time series, renders it very unlikely for the temperature of a single year to exceed the average temperature over the coming decades (Figure 2c).

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

That is, the first year above 1.5 °C occurs within the first 20-year period with an average warming of 1.5 °C. We found the same behaviour for other recent warming levels already reached in observations starting from the 1980s (0.6 °C to 1.0 °C; Figure 1a in the paper).

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

Through climate models, observations, and idealised experiments, we show that unless stringent climate mitigation is implemented, the first year above 1.5°C in 2024 signals that it is highly probable that Earth has already entered the 20-year period that *will* reach the 1.5°C Paris Agreement limit.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

However, the implications for the Paris Agreement's 1.5 °C goal are unclear because the goal is understood to refer to temperature averaged over a 20-30 year period to account for natural short-term variability.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

The year 2024 was announced as the first calendar year to exceed 1.5 °C of global warming by several international organisations that independently track the global temperature, with a multi-dataset mean of 1.55 °C.

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Emanuele Bevacqua @bevacquae.bsky.social · Feb 10

In Nature Climate Change, we show that a year above 1.5 °C signals that Earth is most probably within the 20-year period that will reach the Paris Agreement limit. @natclimchange.bsky.social

A year above 1.5 °C signals that Earth is most probably within the 20-year period that will reach the Paris Agreement limit - Nature Climate Change

What a first year with temperature 1.5 °C above the pre-industrial baseline implies for long-term temperature goals is unclear. Here the authors show that such a first year above the baseline is highl...

www.nature.com

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