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**Greg Cocks** @GregCocks@techhub.social · Feb 18

**Font Free Downloads** @fontfreedownloads@mastodon.social · Dec 17, 2024

**O=C=O** @tuxom@mastodon.social · Mar 25, 2024

Mar 25, 2024

New Zealand's glaciers shrinking faster, scientist warns

"Overall, the #snowline has been rising and in the most recent years we're seeing that rise accelerate, so we're experiencing a continued trend of glacial ice loss," said principal scientist Andrew Lorrey in a statement.

https://phys.org/news/2024-03-zealand-glaciers-faster-scientist.html

"We flew to the southern-most glaciers, ones that we've not seen since 2018," said Lorrey on the back of this year's trip.

"One is now two thirds of the size it was on our last visit," he added.

The institute said that New Zealand had experienced seven of its hottest years on record over the past decade.

Even if this trend was to be reversed, Lorrey said that many glaciers were too far gone to be saved.

#ClimateCrisis #Cryosphere #NewZealand

**Daniel Fischer** @cosmos4u@scicomm.xyz · Nov 8, 2023

**Daniel Fischer** @cosmos4u@scicomm.xyz · Jul 11, 2023

Jul 11, 2023

Daniel Fischer @cosmos4u@scicomm.xyz

JWST reveals excess cool water near the #snowline in compact disks, consistent with pebble drift: https://arxiv.org/abs/2307.03846 -> "JWST-MIRI spectra of four disks, two compact and two large with multiple radial gaps, selected to test the scenario that water vapor inside the snowline is regulated by pebble drift. [...] These spectra clearly reveal excess emission in the low-energy lines in compact disks, compared to the large disks, establishing the presence of a cooler component with T≈ 170-400 K".

arXiv.orgJWST reveals excess cool water near the snowline in compact disks, consistent with pebble driftPrevious analyses of mid-infrared water spectra from young protoplanetary disks observed with the Spitzer-IRS found an anti-correlation between water luminosity and the millimeter dust disk radius observed with ALMA. This trend was suggested to be evidence for a fundamental process of inner disk water enrichment, used to explain properties of the Solar System 40 years ago, in which icy pebbles drift inward from the outer disk and sublimate after crossing the snowline. Previous analyses of IRS water spectra, however, were very uncertain due to the low spectral resolution that blended lines together. We present new JWST-MIRI spectra of four disks, two compact and two large with multiple radial gaps, selected to test the scenario that water vapor inside the snowline is regulated by pebble drift. The higher spectral resolving power of MIRI-MRS now yields water spectra that separate individual lines, tracing upper level energies from 900 K to 10,000 K. These spectra clearly reveal excess emission in the low-energy lines in compact disks, compared to the large disks, establishing the presence of a cooler component with $T \approx$ 170-400 K and equivalent emitting radius $R_{\rm{eq}}\approx$ 1-10 au. We interpret the cool water emission as ice sublimation and vapor diffusion near the snowline, suggesting that there is indeed a higher inwards mass flux of icy pebbles in compact disks. Observation of this process opens up multiple exciting prospects to study planet formation chemistry in inner disks with JWST.

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**RadReduction (Larry Edwards** @RadReduction@spore.social · Dec 21, 2022

Dec 21, 2022

RadReduction (Larry Edwards @RadReduction@spore.social

https://social.bund.de/@DLR/109551526810874272
@DLR
"The #snowline in the #Alps is shifting upwards - this is confirmed by 15,000 images from earth observation #satellites. Less snow also means less #water for the rivers: #Northern Italy experienced one of the worst droughts in 70 years in 2022. The #Landsat data set has enabled the determination of the #snow line in the Alps since 1985.
The details: https://www.dlr.de/content/de/artikel/news"

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