Simon Gascoin

Évolution du jour de déneigement dans les Alpes françaises et les Pyrénées Des scientifiques du CNRS Terre & Univers et du CNRS Ecologie & Environnement ont étudié les bouleversements

[1/5] @sgascoin.bsky.social chercheur CNRS au CESBIO-OMP montre que le jour de déneigement a avancé d’environ 5 jours par décennie depuis 1986 dans les Alpes et les Pyrénées, jusqu’à 10 jours à certaines altitudes. Ce décalage menace l’équilibre des socio-écosystèmes montagnards. #geography

Very nice overview of the recent #GLOF in Pakistan by @sgascoin.bsky.social!
There is so much going on these days, it’s great that various people in the community manage to find time to document these events! Fingers crossed that nobody was harmed. www.cesbio.cnrs.fr/multitemp/ra...

It seems that a human early warning system saved many lives "One of the shepherds, Wasiyat Khan from Rawshan village, was near the glacier when he used his mobile phone to alert the community about the impending flood." tribune.com.pk/story/256303... Pictures from www.linkedin.com/posts/melain...

High resolution image from Google Earth (July 2017) shows the catchment of the lake that collapsed in 2025

Before collapsing, the glacial lake was rapidly growing fed by snow melt.

You're right.. It's obvious when looking at the images in 3D

Yes, I had the same thoughts. Some downstream lakes look a bit bigger and the reason why the debris flow started there is unclear to me as well..

@watershedlab.bsky.social @subfossilguy.bsky.social @davepetley.bsky.social any comment welcome..

My rapid analysis of the recent GLOF (?) in Gupis, Gilgit-Baltistan www.cesbio.cnrs.fr/multitemp/ra...

Trends in the annual snow melt-out day over the French Alps and Pyrenees from 38 years of high-resolution satellite data (1986–2023) Abstract. Information on the spatial–temporal variability of seasonal snow cover duration over long time periods is critical for studying the responses of mountain ecosystems to climate change. Howeve...

Five years in the making.. New study about the snow cover trends in the Alps and Pyrenees tc.copernicus.org/articles/19/...

I suspect someone may have already done this... I took the current NASA Earth fleet chart of operating and planned Earth observing missions and crossed out those recommended for cancellation in the President's budget request. It's disturbing.

Great work - thanks for sharing!

Map of the Lötschtal showing the area affected by the glacier collapse. Blue colors show lost elevation, red areas elevation gains. The two most notable areas are the collapsed peak of Kleines Nesthorn and the collapsed glacier which are shown in deep blue with elevation loss of up to 128m and 51m respectively. The material slid down the mountain in an approximately 400m wide path and accumulated in a 2,5km long area on the valley floor which is up to 32m thick. The newly formed lake above the village of Blatten is also drawn in. The Map text reads: Kleines Nesthorn and Birchgletscher collapse / Blatten im Lötschental (VS) On Wednesday, May 28th, a2025, the Birchgletscher glacier collapsed under the weight of rock and debris following the partial collapse of the Kleines Nesthorn. Approximately 10 million cubic meters of debris flowed into the valley, burying large parts of the villages of Blatten and Ried. The debris also blocked the Lonza River, forming a small lake that destroyed several more houses in Blatten. Analyis Using Oblique imagery collected and provided by swisstopo on May 30th, 2025, a photogrammetric DEM was created and compared to the swissALTI3D DEM. The following volume change was measured in the affected area: Above Volume (m³): 11.2 Mio Below Volume (m³): 10.1 Mio

I also derived a new elevation model from the aerial images, allowing me to visualize the elevation change in the affected areas.
The rocks and debris in the valley are locally up to 32m thick and I estimate the total displaced volume is about 11 million cubic meters. #Blatten

Where Snow and Forest Meet: A Global Atlas A global atlas of the importance of snowfall in forest was calculated at 0.1° resolution from existing reanalysis and tree cover data Snow falls in forest over 23% of the land mass, mostly in the...

Which parts of the world have the snowiest forests? Check our new paper in Geophysical Research Letters and the accompanying online visualisation by Deschamps-Berger et al. agupubs.onlinelibrary.wiley.com/doi/10.1029/...

amazing

Snow melt-out date (SMOD) change spanning four decades in European temperate mountains at 30 m from Landsat time series - Scientific Data Scientific Data - Snow melt-out date (SMOD) change spanning four decades in European temperate mountains at 30 m from Landsat time series

We have generated a Landsat-based dataset to characterize the snow melt-out date in the Pyrenees, Alps, and Greater Caucasus. Data and code available! www.nature.com/articles/s41... by Bayle et al.

Our carbon-intensive lifestyle has a strong impact on the Alps' water cycle and ecosystems. This review by Dumont et al. is a good starter for students and anyone interested in climate change impacts in the Alps. comptes-rendus.academie-sciences.fr/geoscience/a...

a greyscale satelitte image of Musk's data centre - with a bright red marker showing emissions from the many (I think about 30) fossil fuel combustion engines on site

Incredible satellite image of the 33 (!!!!) operational fossil fuel combustion engines at the site of Elon Musk's XAI data centre

“appalling that xAI would operate more than 30 methane gas turbines without any permits or any public oversight"
@selc.bsky.social

www.theguardian.com/technology/2...

Bad news for Heard Island as the US imposes a 10% tariff on its main export - windborne glaciovolcanic tephra. This is viewed as a boost for local Alaskan and Cascadia sources.

Particularly serious implications for very fine grain sizes as the crypto(tephra) market is volatile at the best of times.

YouTube video by Snow International - SINTER SINTER Seminar 03 April 2025 - Shadi Oveisgharan, Franz Meyer

New Sinter seminar online!

Dr. Franz J. Meyer (University of Alaska Fairbanks): "NISAR Data at the Alaska Satellite Facility"

Dr. Shadi Oveisgharan (NASA JPL): "Retrieving Snow Water Equivalent Using InSAR in the Next Decade; Counting Down for NISAR"

youtu.be/-HA2eCHajzg?...

Why? here its a strike-slip earthquake, the scenes are not cloudy and S2 offers a better spatial resolution than S1 for horizontal offset tracking.

Sentinel-2 reveals the surface deformation after the 2025 #Myanmar #earthquake www.cesbio.cnrs.fr/multitemp/se...

Before/after satellite images show the displacement along the fault of the 2025 #Myanmar #earthquake #Sentinel2

RIP Coriolis force, Clausius–Clapeyron relation, bye bye fluid mechanics and thermodynamics.. rdcu.be/efNNg

J'ai modifié mon kit de démarrage destiné aux scientifiques francophones spécialistes du climat, de la biodiversité et de l'environnement en déplaçant les communicateurs et les institutions vers un autre kit.

Si vous pensez que je devrais vous inclure, faites-le moi savoir ! go.bsky.app/LjZgnPy

Conference season is near.
Dear fellow academics, first of all you shouldn't be flying anywhere for a conference, the climate crisis is real ffs.
Second, DO NOT GO TO THE US unless you are cool with being detained, harmed and potentially deported to Salvadoran prison camps.
So: DO NOT GO TO THE US.

@hagolleo.bsky.social "a petition signed by 1,683 Sentinel-2 users, urging ESA to extend Sentinel-2A’s operation"

Superconducting Gravimeter Observations Show That a Satellite‐Derived Snow Depth Image Improves the Simulation of the Snow Water Equivalent Evolution in a High Alpine Site Evaluation of a distributed physically based snow model using superconducting gravimetry in a high alpine area Precipitation scaling based on a single satellite snow depth image significantly imp...

In this study we show that a single satellite snow depth image significantly improves a snowpack model in a high alpine site (Zugspitze, Germany). This result is based on the evaluation of the simulated gravity signal against superconducting gravimeter measurements. doi.org/10.1029/2024...

Immediate Expansion of American Timber Production By the authority vested in me as President by the Constitution and the laws of the United States of America, it is hereby ordered: Section 1.  Purpose.

So that's the beginning of the end for US Old Growth Forests then, prepare for massive biodiversity and carbon loss, here billed as the opposite www.whitehouse.gov/presidential... 🌎

Glad to share our paper published in the journal “Science” titled “The Sikkim flood of October 2023: Drivers, causes and impacts of a multihazard cascade.” www.science.org/doi/10.1126/...