eupolicy.social is one of the many independent Mastodon servers you can use to participate in the fediverse.
This Mastodon server is a friendly and respectful discussion space for people working in areas related to EU policy. When you request to create an account, please tell us something about you.

Server stats:

225
active users

#geophysics

2 posts2 participants0 posts today
UK<p><a href="https://www.europesays.com/uk/252598/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://www.</span><span class="">europesays.com/uk/252598/</span><span class="invisible"></span></a> Recent southwestern US drought exacerbated by anthropogenic aerosols and tropical ocean warming <a href="https://pubeurope.com/tags/AtmosphericScience" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>AtmosphericScience</span></a> <a href="https://pubeurope.com/tags/ClimateChange" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>ClimateChange</span></a> <a href="https://pubeurope.com/tags/EarthSciences" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>EarthSciences</span></a> <a href="https://pubeurope.com/tags/EarthSystemSciences" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>EarthSystemSciences</span></a> <a href="https://pubeurope.com/tags/Environment" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Environment</span></a> <a href="https://pubeurope.com/tags/general" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>general</span></a> <a href="https://pubeurope.com/tags/Geochemistry" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Geochemistry</span></a> <a href="https://pubeurope.com/tags/Geology" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Geology</span></a> <a href="https://pubeurope.com/tags/Geophysics" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Geophysics</span></a>/Geodesy <a href="https://pubeurope.com/tags/Science" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Science</span></a> <a href="https://pubeurope.com/tags/UK" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>UK</span></a> <a href="https://pubeurope.com/tags/UnitedKingdom" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>UnitedKingdom</span></a></p>
Dr. Evan J. Gowan<p>Brandes et al present a review of the history of investigations of the forebulge from the North American and Eurasian ice sheets. The collapse of the forebulge is responsible for rising relative sea level along the east coast of the United States.</p><p><a href="https://fediscience.org/tags/SeaLevel" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>SeaLevel</span></a> <a href="https://fediscience.org/tags/GlacialIsostaticAdjustment" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>GlacialIsostaticAdjustment</span></a> <a href="https://fediscience.org/tags/Geophysics" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Geophysics</span></a> <a href="https://fediscience.org/tags/IceSheets" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>IceSheets</span></a></p><p> <a href="https://doi.org/10.1029/2024RG000852" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="">doi.org/10.1029/2024RG000852</span><span class="invisible"></span></a></p>
Nicole Sharp<p><strong>Martian Streaks Are Dry</strong></p><p>Dark lines appearing on Martian slopes have triggered theories of flowing water or brine on the planet’s surface. But a <a href="https://doi.org/10.1038/s41467-025-59395-w" rel="nofollow noopener" target="_blank">new study suggests</a> that these features are, instead, dry. To explore these streaks, the team assembled a global database of sightings and correlated their map with other known quantities, like temperature, wind speed, and rock slides. By connecting the data across thousands of streaks, they could build statistics about what variables correlated with the streaks’ appearance.</p><p>What they found was that streaks didn’t appear in places connected to liquid water or even frost. Instead, the streaks appeared in spots with high wind speeds and heavy dust accumulation. The team included that, rather than being moist areas, the streaks are dry and form when dust slides down the slope, perhaps triggered by high winds or passing dust devils.</p><p>Although showing that the streaks aren’t associated with water may seem disappointing, it may mean that NASA will be able to explore them sooner. Right now, NASA avoids sending rovers anywhere near water, out of concern that Earth microbes still on the rover could contaminate the Martian environment. (Image credit: NASA; research credit: <a href="https://doi.org/10.1038/s41467-025-59395-w" rel="nofollow noopener" target="_blank">V. Bickel and A. Valantinas</a>; via <a href="https://gizmodo.com/bizarre-streaks-on-mars-arent-caused-by-water-after-all-study-suggests-2000605177?__readwiseLocation=" rel="nofollow noopener" target="_blank">Gizmodo</a>)</p><p><a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://fyfluiddynamics.com/tagged/fluid-dynamics/" target="_blank">#fluidDynamics</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://fyfluiddynamics.com/tagged/geophysics/" target="_blank">#geophysics</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://fyfluiddynamics.com/tagged/mars/" target="_blank">#Mars</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://fyfluiddynamics.com/tagged/physics/" target="_blank">#physics</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://fyfluiddynamics.com/tagged/planetary-science/" target="_blank">#planetaryScience</a> <a rel="nofollow noopener" class="hashtag u-tag u-category" href="https://fyfluiddynamics.com/tagged/science/" target="_blank">#science</a></p>

Io’s Missing Magma Ocean

In the late 1970s, scientists conjectured that Io was likely a volcanic world, heated by tidal forces from Jupiter that squeeze it along its elliptical orbit. Only months later, images from Voyager 1’s flyby confirmed the moon’s volcanism. Magnetometer data from Galileo’s later flyby suggested that tidal heating had created a shallow magma ocean that powered the moon’s volcanic activity. But newly analyzed data from Juno’s flyby shows that Io doesn’t have a magma ocean after all.

The new flyby used radio transmission data to measure any little wobbles that Io caused by tugging Juno off its expected course. The team expected a magma ocean to cause plenty of distortions for the spacecraft, but the effect was much slighter than expected. Their conclusion? Io has no magma ocean lurking under its crust. The results don’t preclude a deeper magma ocean, but at what point do you distinguish a magma ocean from a body’s liquid core?

Instead, scientists are now exploring the possibility that Io’s magma shoots up from much smaller pockets of magma rather than one enormous, shared source. (Image credit: NASA/JPL/USGS; research credit: R. Park et al.; see also Quanta)

Ponding on the Ice Shelf

Glaciers flow together and march out to sea along the Amery Ice Shelf in this satellite image of Antarctica. Three glaciers — flowing from the top, left, and bottom of the image — meet just to the right of center and pass from the continental bedrock onto the ice-covered ocean. The ice shelf is recognizable by its plethora of meltwater ponds, which appear as bright blue areas. Each austral summer, meltwater gathers in low-lying regions on the ice, potentially destabilizing the ice shelf through fracture and drainage. This region near the ice shelf’s grounding line is particularly prone to ponding. Regions further afield (right, beyond the image) are colder and drier, often allowing meltwater to refreeze. (Image credit: W. Liang; via NASA Earth Observatory)

Happy birthday to Danish #seismologist Inge Lehmann (1888 – 1993) who demonstrated that the Earth’s core is not a single molten sphere, but contained an inner solid core, in ‘36. She was a pioneer #womanInScience, a brilliant seismologist & lived to be 105.⁠

As she first postulated, the #earth has roughly 3 equal concentric sections: mantle, liquid outer core & solid inner core. The crust, on which we live is merely 🧵1/n

On the Mechanics of Wet Sand

Sand is a critical component of many built environments. As most of us learn (via sand castle), adding just the right amount of water allows sand to be quite strong. But with too little water — or too much — sand is prone to collapse. For those of us outside the construction industry, we’re most likely to run into this problem on the beach while digging holes in the sand. In this Practical Engineering video, Grady explains the forces that stabilize and destabilize piled sand and where the dangers of excavation lie. (Video and image credit: Practical Engineering)

Our own @BaerbelW traveled to Vienna for this year's #EGU25 General Assembly of the @EuroGeosciences

Baerbel herself did a couple of presentations in Vienna:

* Examples of Skeptical Science successfully collaborating with other organizations so as to better reach shared goals, get more gain for less effort. With so much reward, we're eager to do more.

* How Skeptical Science translates our content into 29 different languages, the challenges of maintaining a polyglot presence. You may be able to help!

Baerbel also kept a daily journal. It's loaded with links to scads of intriguing information presented at the assembly by many researchers, with teasers and organized for easy access.

Post facto virtual attendance , distilled and at our fingertips. :-)

#geoscience
#geophysics
#ScienceCommunication

skepticalscience.com/egu25-per

Martian Mud Volcanoes

Mars features mounds that resemble our terrestrial mud volcanoes, suggesting that a similar form of mudflow occurs on Mars. But Mars’ thin atmosphere and frigid temperatures mean that water — a prime ingredient of any mud — is almost always in either solid or gaseous form on the planet. So researchers explored whether salty muds could flow under Martian conditions. They tested a variety of salts, at different concentrations, in a low-pressure chamber calibrated to Mars-like temperatures and pressures. The salts lowered water’s freezing point, allowing the muds to remain fluid. Even a relatively small amount of sodium chloride — 2.5% by weight — allowed muds to flow far. The team also found that the salt content affected the shape the flowing mud took, with flows ranging from narrow, ropey patterns to broad, even sheets. (Image credit: P. Brož/Wikimedia Commons; research credit: O. Krýza et al.; via Eos)

Bifurcating Waterways

Your typical river has a single water basin and drains along a river or two on its way to the sea. But there are a handful of rivers and lakes that don’t obey our usual expectations. Some rivers flow in two directions. Some lakes have multiple outlets, each to a separate water basin. That means that water from a single lake can wind up in two entirely different bodies of water.

The most famous example of these odd waterways is South America’s Casiquiare River, seen running north to south in the image above. This navigable river connects the Orinoco River (flowing east to west in this image) with the Rio Negro (not pictured). Since the Rio Negro eventually joins the Amazon, the Casiquiare River’s meandering, nearly-flat course connects the continent’s two largest basins: the Orinoco and the Amazon.

For more strange waterways across the Americas, check out this review paper, which describes a total of 9 such hydrological head-scratchers. (Image credit: Coordenação-Geral de Observação da Terra/INPE; research credit: R. Sowby and A. Siegel; via Eos)