Stella Bourdin

Le changement climatique (CC) n'augmente pas le nombre de cyclones mais la proportion des +intenses. Dit autrement, le CC inhibe en moyenne la formation des cyclones mais quand ils se forment, ils s'intensifient +rapidement, sont de catégories +élevées avec des effets (inondations...) démultipliés.

Here’s a 48-hour water vapor loop of Ex-Hurricane Erin spinning on its final approach to Europe. Truly mesmerizing.

The HuracanPy JOSS paper is officially out! 🌀
If you ever find yourself working with cyclone track data, we hope you'll find it useful! Feel free to contribute suggestions and code!
doi.org/10.21105/jos...

Qques mots forts que j'ai prononcés avec émotion @franceinfo.fr
C'est un mensonge de laisser croire que l'on s'adaptera sans casse irréversible dans une France à 4°C. On ne s'adapte pas a un effondrement de la biodiversité; on meurt avec!
Les régressions actuelles sont irresponsables & suicidaires.

« A Mayotte ou Valence, en Espagne, il serait réducteur d’attribuer la gravité des dégâts matériels et humains uniquement au changement climatique » TRIBUNE. Ne se concentrer que sur le rôle du changement climatique tend à invisibiliser les autres causes fondamentales des catastrophes dites « naturelles », très souvent liées à des choix historique...

Il est cynique d'invoquer le changement climatique quand cela arrange pour invisibiliser les autres causes des catastrophes liées à des choix historiques&politiques (vulnérabilités). Raisonner ainsi actera l’échec de l'adaptation. Nous climatologues, le dénonçons!
Fil🧵
www.lemonde.fr/idees/articl...

The storm's remnants meandered until they reached the Portuguese coast, where they dissipated.
There, they brought heavy rains (up to 84mm/24h), and numerous incidents were reported including downed trees and flash floods. One man was injured.

Danielle was identified as Tropical Storm Danielle on Sept. 1st. It became a hurricane the next day. It sustained itself for a few days thanks to abnormally warm waters and light shear, alternating between tropical storm and cat. 1. On Sept. 8, it finally transitioned into an extra-tropical cyclone.

By NASA/NOAA-20 - https://worldview.earthdata.nasa.gov/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=122659414

📆 Ex-hurricanes advent calendar day 24/24: Danielle 2022. 🌀
Last of our series is Danielle 2022! Another subtropical storm, which caused flooding and landslides in Portugal.

Mayotte, à qui la faute? Alors que l’on ne connaît toujours pas le nombre de décès consécutifs au passage du Cyclone Chido, qui a ravagé Mayotte

"Chaque désastre est devenu une opportunité pour faire triompher ses valeurs, son idéologie et ses convictions, quitte à se livrer parfois à une instrumentalisation écœurante."
Analyse de @magalireghezza.bsky.social sur la situation à Mayotte
bonpote.com/mayotte-a-qu...

Day 20: Lorenzo 2019
bsky.app/profile/stel...

On Oct. 4th, the storm reached Ireland while Met Eireann had issued an orange warning for six counties and yellow for the rest of the country. Strong gusts damaged infrastructure and cut electricity. Some flooding was reported. In the UK, one person was killed after being struck by a falling tree.

Although the storm was very far from the american coasts, 8 persons drowned after being caught in rip currents, or swept away by strong waves.

On Sept 26th, a ship sank with 14 crew members on board. Only three of them could be rescued.

Lorenzo at peak intensity By NASA - https://worldview.earthdata.nasa.gov/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=82665868

After an eyewall replacement cycle, it re-intensified to reach cat. 5 on Sept. 29th, becoming the easternmost cat. 5 Atlantic hurricane. At this stage, it was moving poleward, and starting recurvating towards Europe.

Back to tropical wave hurricanes, Lorenzo formed from an African Easterly wave right off the coast on Sept . 22nd. Evolving in very favourable conditions, the system quickly organised and intensified until it reached first time category 4 on Sept. 27th.

By EOSDIS Worldview — Terra/MODIS - EOSDIS Worldview, Public Domain, https://commons.wikimedia.org/w/index.php?curid=82793891

📆 Ex-hurricanes advent calendar day 20/24: Lorenzo 2019. 🌀
Lorenzo was a category 5 major hurricane over the open Atlantic Ocean, that reached Ireland after having substantially weakened.

Day 19: Leslie 2018
bsky.app/profile/stel...

In France, Leslie participated in a circulation that caused extremely severe flooding: 295mm of precipitation accumulating over only 12h made the river Aude rise by more than 7m. 15 persons died as a consquence of the floods.

In Portugal, the storm brought gusts up to 190km/h, likely associated with a sting jet. It was the worst storm Portugal had experienced since 1842. Leslie made 2 casualties and extensive infrastructural damage.

Leslie reached its maximum intensity on Oct. 12th. about 36h, it completed transition, very close to the Portugese coast, and only a few hours before making landfall.

Leslie, like Ophelia (2017) was a subtropical storm that underwent tropical transition. It had a very erratic path and went through two cycles of intensification, during which it reached cat. 1. After completing two loops, the cyclone went straight to the Iberian peninsula.

By NASA - https://worldview.earthdata.nasa.gov/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=73593118

📆 Ex-hurricanes advent calendar day 19/24: Leslie 2018. 🌀
Leslie was a rather unusual subtropical storm that nearly hit Portugal with tropical characteristics. It made 2 direct and 15 indirect victims.

Day 18: Ophelia 2017
bsky.app/profile/stel...

In Ireland, two persons were killed by a tree falling on their car, and several other died in the aftermath of the storm while working on the repairs. The storm also impacted the UK and Eastern Europe, with no reported victims. Insurance claims amounted to nearly $90 million (2017 USD).

Met Eireann issued a red warning more than 48h in advance, anticipating a formidable storm already. On October 16th, the storm made landfall, bringing gusts up to 191km/h.

After its peak, Ophelia moved quickly northward, and started weakening as it encountered shear conditions. It completed transition early on Oct. 16th at ~47°N, while still being associated with cat. 1 winds. It then made landfall in Ireland.

At this stage, Ophelia approached the Iberian peninsula. Resulting winds are thought to have helped to develop wildfires that made at least 49 victims.

Ophelia at peak intensity By National Aeronautics and Space Administration, LANCE/EOSDIS Rapid Response, captured on Suomi NPP satellite - https://lance.modaps.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=Ophelia.A2017287.1454.375m.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=63381519

It reached it peak intensity, cat. 3, on Octber 14th, while at ~35°N, and 27.7°W, becoming the farthest east a cat. 3 hurricane was observed in the satellite era. At this peak maximum winds attained 185 km/h, and minimum pressure 959 hPa.

Hurricane Ophelia near its initial peak intensity on 12 October By National Aeronautics and Space Administration, LANCE/EOSDIS Rapid Response, captured on Suomi NPP satellite - https://lance-modis.eosdis.nasa.gov/cgi-bin/imagery/single.cgi?image=Ophelia.A2017285.1530.375m.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=63349566

Recording by the NHC started Oct. 7th. The storm gained in intensity and developped more and more tropical characteristics, until it was classified as a hurricane on October 11th. It then intensified, reaching cat. 2 on Oct. 12th.

Ophelia is the first case in our list that does not form from a tropical wave in the deep tropics, but rather as a subtropical cyclone undergoing tropical transition (the process through which an extra-tropical cyclone can become a tropical cyclone given the right conditions).