Uploaded October 2021 | Updated September 2026, 3 weeks ago
CAMBRIDGE, MASSACHUSETTS — The melting of Earth's polar ice is incrementally warping the planet’s crust both vertically and horizontally, according to a new study in the Geophysical Research Letters journal.
Scientists already knew about a process called isostatic rebound, whereby when a glacier melts, the crust below it is released from the weight previously on top of it, and so very gradually rises up, in some cases over thousands of years.
However, the new study, cited by Sci Tech Daily, adds to this concept, noting that the deformation of the crust is actually three-dimensional, and thus includes horizontal movements as well as vertical ones.
The study adds that rather than simply affecting the areas directly below the ice loss, deformation was also found to have global impacts, with Greenland ice sheet and Arctic glacier melting causing deformation that extends over much of the Northern Hemisphere, for instance.
Case studies showing the incremental scale of the deformation include London, which the study says moved, roughly, between 0.04 and almost 0.2 millimeters vertically every year from 2006 to 2010, plus similar distances to the north and east.
CAMBRIDGE, MASSACHUSETTS — The melting of Earth's polar ice is incrementally warping the planet’s crust both vertically and horizontally, according to a new study in the Geophysical Research Letters journal.
Scientists already knew about a process called isostatic rebound, whereby when a glacier melts, the crust below it is released from the weight previously on top of it, and so very gradually rises up, in some cases over thousands of years.
However, the new study, cited by Sci Tech Daily, adds to this concept, noting that the deformation of the crust is actually three-dimensional, and thus includes horizontal movements as well as vertical ones.
The study adds that rather than simply affecting the areas directly below the ice loss, deformation was also found to have global impacts, with Greenland ice sheet and Arctic glacier melting causing deformation that extends over much of the Northern Hemisphere, for instance.
Case studies showing the incremental scale of the deformation include London, which the study says moved, roughly, between 0.04 and almost 0.2 millimeters vertically every year from 2006 to 2010, plus similar distances to the north and east.


![Tonga Volcano Eruptions: Underwater Volcano Erupts, Triggering Tsunami Warnings
THE HUNGA-TONGA-HUNGA-HAAPAI VOLCANO, TONGA — The “once in 1,000 years” eruption of the Hunga-Tonga Hunga-Haapai[c] volcano on Saturday did not emerge from smaller volcanic cones as in previous eruptions in 2009 and across 2014 and 2015. Rather, it blasted out of a five-kilometer-wide underwater caldera, according to Shane Cronin, Professor of Earth Sciences at the University of Auckland.
The power of the explosion is likely because magma rose up from the caldera so quickly there was no time for a film of steam to form and allow the magma’s surface to cool as it passed through the water.
Instead, hot magma came into direct contact with cold water, creating explosions which split the magma up and forced it into further contact with additional cold water, causing additional explosions.
The resulting blast reached supersonic speeds, sending out a sonic boom that reached New Zealand, according to The Associated Press.
Unusually high waves drowned two people in Peru and caused widespread tsunami alerts elsewhere.
Damage to internet connections meant that very little news of the volcano’s impact on Tonga was available initially, though The Associated Press reported tsunami waves crashing across the shore and people rushing to higher ground.
Two smaller eruptions occurred at the same volcano on December 20 and January 13, and previous 1,000-year major caldera eruption episodes involved many separate explosion events, meaning several weeks or even years of major volcanic unrest could be due, according to Professor Cronin’s article on The Conversation.
In line with this reasoning, CNN reported on Monday that the volcano had erupted again, for the third time in four days, though unlike Saturday’s eruption, which was likely the biggest recorded anywhere on the planet in more than 30 years, there were no additional tsunami alerts. Tonga Volcano Eruptions: Underwater Volcano Erupts, Triggering Tsunami Warnings](https://i.ytimg.com/vi/vbQ7E84wU6Q/mqdefault.jpg)

![Ukraine’s Giant Bomb Shelter: Ukrainians Fleeing to Kyiv Metro System
KYIV, UKRAINE — As military experts warn that Russia may be shifting tactics, increasingly using artillery and air bombardments to ‘pulverize’ cities as they previously did in Chechnya and Syria, according to The Associated Press, Kyiv’s metro is operating as a citywide bomb shelter.
In the last week, Russia has bombarded Kyiv with missile strikes, with troops attempting to push into the city from the northwest and the Kyiv TV tower hit by a projectile on March 1.
The New Yorker explains that the situation is seeing metro stations in Kyiv fill with as many as 15,000 civilians every night in search of safety.
The system of 52 metro stations is home to famous historic features dating back to the Soviet era. Its Arsenalna [d]station is the deepest in the world at 105 meters below ground level. Ukraine’s Giant Bomb Shelter: Ukrainians Fleeing to Kyiv Metro System](https://i.ytimg.com/vi/vqgiQ-xD11c/mqdefault.jpg)





