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"Satellite-based evidence of recent decline in global forest recovery rate from tree mortality events" by Yuchao Yan et al 2025.
Fascinating and educational. All the more for us in Germany and Finland, and likely other Europeans, whose forests morphed from CO2 sink to source. The study ends with 2020 data tho, Europe with 2018.
Only non-fire mortality events were analyzed.
I learned how recovery after a drought-driven forest mortality event depends on🌡️💧during recovery; not so much the event severity.
nature.com/articles/s41477-025
Free e-pdf provided by one of the authors:
rdcu.be/eigV4

Don't know about you but to me, a paper is particularly "good" if I'm left with a host of new pressing questions. "Why did they..? Was it maybe ..? What if it had been...?"

For a recovery phase, they differentiate between recovery of the canopy greening and recovery of water content in the canopy. Both are based on satellite obs only. And if a satellite image suggests greening is recovered to pre-mortality level, it might not actually be re-greening from recovered old or new young trees but could be merely dense shrubbery. The Greening parameter is often used to glean carbon stock. Shrubs have less biomass=less carbon than trees.
The water content in the canopy then somehow helps to clarify the actual recovery state. How? 🤷‍♀️

Water content in canopy always takes far longer to recover than re-greening.
Longer = years and years longer.
Always = in the 1980s as well. Which I take as: that's the normal baseline behaviour for a given biome, a given latitude zone, a given climate zone, a given elevation, a given human intervention etc.

Supplementary Fig. 5. c and d show numbers for North America and Tropics static-content.springer.com/es .
Recovery Time in years for water in canopy in North America
in the 1990s took 2 - 12, average 6.
in the 2000s took 2 - 18, average 9.

in the Tropics:
in the 1990s took 2 - 12, average 6.
in the 2000s took 2 - 11, average 7.

Europe is missing an extra whiskers plot. Maybe they saved this for their next paper. But European events are included up to 2018, if I got it right.

With all the factors to be considered, and bias in numbers of events in any given factor, making recovery comparable across regions, across biomes, across climate zones, a global average doesn't seem very useful.
However, here are the global numbers from Figure 1d for
Recovery time RT for water in canopy. In the 1980s RT was between 2 and 15, average 8, median 6 .
In the 1990s, RT was 2 - 22, average 8, median 6.
In the 2000s, RT was 2 - 20, average 9, median 9 years.

Am curious wrt the missing potential cause for the greatly reduced RecoveryTime in the 2010s in Fig.1d. Is that an artefact of the shortened observation time for these 10 most recent mortality yrs?
And Greening recovered astonishingly quickly in the 2010s. is it the high CO2 fertilisation or a regional bias from the events in this period?

NatureSatellite-based evidence of recent decline in global forest recovery rate from tree mortality events - Nature PlantsSatellite data show declining global forest recovery from tree mortality since the 1990s, driven by warming and water scarcity. Canopy water recovers slower than greenness, stressing the need for a multifaceted approach to assessing recovery.

Tornado Quest Top Science Links For April 12 – 19, 2025  

Xenia, Ohio F-5 tornado on April 3, 1974 Greetings to all and thanks for stopping by. The tornado and severe weather season is well underway with 2025 having already seen several substantial severe weather and tornado events. The bulk of the activity is yet to come. Your tornado safety information will be posted again this week along with a reminder on lightning safety.

tornadoquest.org/2025/04/19/to

TORNADO QUEST · Tornado Quest Top Science Links For April 12 – 19, 2025 #science #weather #climate #climatechange #drought #tornadoXenia, Ohio F-5 tornado on April 3, 1974 Greetings to all and thanks for stopping by. The tornado and severe weather season is well underway with 2025 having already seen several substantial severe…

Aktueller Stand der Dürre in Deutschland
Die blauen Flächen in der rechten Grafik ist das was durch den neulichen Regen hinzukam aber nach einem Tag mit blauem Himmel wieder verdunstet ist. Die Vegetation bekam einen Wachstusschub, mal kurz. Da wo Deutschlands Bäume wurzeln ist es sehr trocken/extrem trocken/außergewöhnlich trocken.

Wer denkt daran, zündet er das #Osterfeuer an?

Der Plan für Ostern 25 soweit:

Erst kommen die Überschwemmungen, dann die Osterfeuer und danach die Waldbrände, die dauern dann länger. In den Nachrichtenmeldungen. Der Regen mal am Rande erwähnt, weil Klima Sache. Osterfeuer werden nur erwähnt, wenn es eine Gemeinde verboten hat.
Kommen wir zu den Waldbränden. Das von Trockenheit am Meisten betroffene Gebiet, ist der rechte Rand auf der Landkarte. Da wo rechts normal ist und Traditionen bewahrt werden.

🇬🇧 **Extreme drought contributed to barbarian invasion of late Roman Britain, tree-ring study reveals**

“_Researchers argue that Picts, Scotti and Saxons took advantage of famine and societal breakdown caused by an extreme period of drought to inflict crushing blows on weakened Roman defences in 367 CE. While Rome eventually restored order, some historians argue that the province never fully recovered._”

🔗 cam.ac.uk/research/news/extrem.

#History #Histodon #Histodons #Romans #RomanEmpire #Britain #UK #UnitedKingdom #Drought @histodon @histodons

University of CambridgeExtreme drought contributed to barbarian invasion of late Roman Britain, tree-ring study revealsThree consecutive years of drought contributed to the ‘Barbarian Conspiracy’, a pivotal moment in the history of Roman Britain, a new Cambridge-led study