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Rapid melting of Petermann Glacier signals even worse sea level rise



A shocking study of Petermann Glacier in northwest Greenland by researchers from the University of California, Irvine (UCI) and NASA’s Jet Propulsion Laboratory has revealed a previously unknown interaction between ice and ocean.

This leads to the possibility that the climate community has been significantly underestimating the impact of polar ice deterioration on future sea level rise. This important discovery could have far-reaching implications for our understanding of climate change and its consequences.

The team of scientists used satellite radar data from three European missions to analyze the behavior of Petermann Glacier’s grounding line, where the ice detaches from the land bed and begins floating in the ocean.

What the researchers found at Petermann Glacier

Contrary to previous beliefs, they found that the grounding line shifts substantially during tidal cycles, allowing warm seawater to intrude and accelerate ice melt. The findings are detailed in a paper published in Proceedings of the National Academy of Sciences.


Lead author Enrico Ciraci, UCI assistant specialist in Earth system science and NASA postdoctoral fellow, explained: “Petermann’s grounding line could be more accurately described as a grounding zone because it migrates between 2 and 6 kilometers as tides come in and out. This is an order of magnitude larger than expected for grounding lines on a rigid bed.”

The traditional view of grounding lines beneath ocean-reaching glaciers did not account for this migration or ice melt during tidal cycles. However, the new study reveals that warm ocean water penetrates beneath the ice through preexisting subglacial channels, leading to the highest melt rates at the grounding zone.

As the glacier’s grounding line retreated nearly 4 kilometers (2½ miles) between 2016 and 2022, the researchers observed that warm water carved a 670-foot-tall cavity in the underside of the glacier. Remarkably, this cavity persisted throughout 2022.

Senior co-author Eric Rignot, UCI professor of Earth system science and NASA JPL research scientist, emphasized the significance of these findings, stating, “These ice-ocean interactions make the glaciers more sensitive to ocean warming.”

Models for future sea level rise must now be rebuilt

Current models do not include these ice-ocean dynamics, which, if accounted for, could increase projections of sea level rise by up to 200 percent – impacting not just Petermann Glacier but all glaciers ending in the ocean, including those in northern Greenland and Antarctica.

This discovery highlights the urgent need to update our understanding of glacier behavior in response to climate change.

The paper emphasizes that the Greenland ice sheet has lost billions of tons of ice to the ocean in recent decades, primarily due to warming of subsurface ocean waters – a consequence of Earth’s changing climate.

Rignot explains that exposure to ocean water vigorously melts ice at the glacier front, eroding resistance to the movement of glaciers over the ground and causing the ice to slide more quickly into the sea.

This groundbreaking research underscores the importance of refining our climate models to predict the future consequences of climate change and inform our response to this global crisis more accurately.

More about Petermann Glacier

Petermann Glacier is a large and significant glacier located in northwest Greenland. It is one of the largest floating ice shelves in the Northern Hemisphere, extending over an area of approximately 1,295 square kilometers.

The glacier is fed by the Greenland Ice Sheet and discharges into the Nares Strait, which separates Greenland from Ellesmere Island in the Canadian Arctic Archipelago. Petermann Glacier plays a vital role in draining the Greenland Ice Sheet and contributes to global sea level rise through the calving of icebergs and melting of its ice.

Several aspects make Petermann Glacier a subject of interest for climate scientists and glaciologists:

Ice shelf dynamics

The floating ice shelf at the terminus of Petermann Glacier is crucial for understanding the stability and dynamics of ice shelves. The interaction between the ice shelf and ocean waters provides insights into how ocean warming can impact ice shelf stability and glacier flow.

Calving events

Petermann Glacier has experienced several major calving events in recent years, with the most notable ones occurring in 2010 and 2012. These events resulted in the detachment of massive icebergs from the glacier’s floating ice shelf, raising concerns about the stability of the glacier and its contribution to sea level rise.

Grounding line migration

A recent study by researchers from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory revealed that the grounding line of Petermann Glacier, where the ice detaches from the land bed and starts to float, migrates between 2 and 6 kilometers during tidal cycles. This previously unknown interaction between ice and ocean allows warm seawater to infiltrate and accelerate ice melt, potentially leading to underestimations of sea level rise caused by polar ice deterioration.

Climate change and sea level rise

Petermann Glacier, along with other glaciers in Greenland, is losing ice due to climate change. As a consequence of increasing temperatures and subsurface ocean warming, the glacier is melting at a faster rate, contributing to global sea level rise.

Research and monitoring

Due to its significance in understanding glacier dynamics, ice-ocean interactions, and the impact of climate change on ice sheets, Petermann Glacier has become a focal point for researchers and is closely monitored using satellite data, field measurements, and remote sensing techniques.

In summary, Petermann Glacier is a crucial component of the Greenland Ice Sheet and plays a vital role in understanding the impacts of climate change on glacier dynamics, ice-ocean interactions, and global sea level rise. Its behavior and stability have far-reaching implications for coastal communities and ecosystems worldwide.

More about global sea level rise

Global sea level rise is one of the most critical consequences of climate change, posing a significant threat to coastal ecosystems, infrastructure, and human populations. As Earth’s climate warms due to the increase in greenhouse gases, such as carbon dioxide and methane, two primary factors contribute to the rising sea levels: thermal expansion of ocean waters and the melting of land-based ice.

Thermal expansion

As ocean temperatures increase, seawater expands, occupying more volume. This expansion, known as thermal expansion, contributes to approximately half of the observed sea level rise. The upper layer of the ocean, which is in direct contact with the atmosphere, warms faster, causing water to expand and occupy more space, subsequently leading to a rise in sea level.

Melting of land-based ice

The melting of ice sheets and glaciers also contributes significantly to sea level rise. Ice sheets in Greenland and Antarctica contain vast amounts of frozen water, and their accelerated melting due to climate change has a substantial impact on global sea levels. Additionally, the melting of mountain glaciers worldwide, particularly in regions like the Himalayas, the Andes, and the Alps, adds to the rising sea levels.

Recent research suggests that ice loss from Greenland, Antarctica, and mountain glaciers has accelerated over the past few decades, causing the rate of global sea level rise to increase. From 1993 to 2021, the global sea level rose at an average rate of approximately 3.3 millimeters per year, and this rate is projected to increase further as climate change intensifies.

The consequences of sea level rise are far-reaching and pose significant risks to coastal communities, infrastructure, and ecosystems. Some of the most severe impacts include:

Flooding and erosion

As sea levels rise, the frequency and severity of coastal flooding and erosion increase, putting lives, property, and infrastructure at risk.

Saltwater intrusion

Rising sea levels can cause saltwater to intrude into freshwater resources, such as rivers and aquifers, threatening freshwater supplies and agricultural lands.

Loss of coastal habitats

Sea level rise can lead to the loss of vital coastal habitats, such as wetlands, mangroves, and coral reefs, which provide essential ecosystem services and act as natural barriers against storm surges and erosion.

Displacement of human populations

Low-lying coastal areas and small island nations are particularly vulnerable to sea level rise, which can lead to the displacement of millions of people, creating significant social, economic, and political challenges.

Mitigating global sea level rise requires urgent and concerted efforts to reduce greenhouse gas emissions, promote climate adaptation strategies, and improve our understanding of ice sheet dynamics and ocean processes. As the impacts of sea level rise are already being felt worldwide, it is crucial to act now to reduce future risks and protect vulnerable communities and ecosystems.


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How to watch the Axiom-2 mission depart from the ISS on Tuesday



This Tuesday, the crew of the second-ever all-private mission to the International Space Station will be returning to Earth. The Axiom 2 or Ax-2 mission launched last week and saw private astronauts Peggy Whitson, John Shoffner, Ali Alqarni, and Rayyanah Barnawi traveling to the ISS on a SpaceX Crew Dragon launched from the Kennedy Space Center in Florida.

Axiom Mission 2 Undocks From the International Space Station (Official NASA Broadcast)

Now, the crew of four will be traveling back to Earth in the same Crew Dragon, and NASA will be livestreaming the departure of the spacecraft from the station. A separate stream will also be available showing the Crew Dragon splashing down off the coast of Florida. We’ve got the details on how to watch both below.

How to watch the mission departure

The Axiom Mission-2 and Expedition 69 crew members pose for a portrait together during dinner time aboard the International Space Station. NASA

Coverage of the departure of the Crew Dragon from the ISS will begin at 9 a.m. ET (6 a.m. PT) on Tuesday, May 30. NASA will show a short introduction before the closing of the hatch of the station’s Harmony module at 9:10 a.m. ET (6:10 a.m. PT). There will then be a short break in coverage, which will resume at 10:45 a.m. ET (7:45 a.m. PT) to show the undocking of the Dragon at 11:05 a.m. ET (8:05 a.m. PT), with coverage ending 30 minutes after undocking.

You can watch the livestream of the hatch closing and the undocking on NASA’s YouTube channel, or by using the video embedded near the top of this page.


The crew will then travel back to Earth throughout Tuesday and into Wednesday, May 31. When the Crew Dragon is approaching Earth for splashdown, you’ll be able to tune into a livestream from Axiom Space. That will be available on Axiom’s website, but the company has not yet confirmed the exact time that coverage is expected to begin on Wednesday. You can find the latest updates on Axiom Twitter.

What to expect from the mission departure

The Ax-2 crew will have spent 10 days in space before heading home, and they will be bringing around 300 pounds of cargo back with them. The mission is notable for including the first two astronauts from Saudi Arabia, Ali Alqarni and Rayyanah Barnawi, as well as famous American astronaut Peggy Whitson who has spent more days in space than any other American or any other woman.

Axiom Space launched its first private mission to the ISS in April last year, with a third mission planned for November this year and a fourth planned for 2024.



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NASA's New Horizons Spacecraft Captures ''Heart-Shaped'' Glacier On Pluto's Surface – NDTV





Pluto was once considered the ninth planet in the solar system

Space agency NASA routinely captures stunning images of our universe, leaving space lovers mesmerized. On Sunday, NASA shared a stunning image on Instagram taken by its New Horizons spacecraft showing a heart-shaped glacier on Pluto’s surface. The heart-shaped region is known unofficially as Tombaugh Regio and is made of nitrogen and methane.


The image was captioned as ”Absence makes the heart grow fonder. Our New Horizons spacecraft captured this heart-shaped glacier. It lies on Pluto’s surface, which also features mountains, cliffs, valleys, craters, and plains, thought to be made of methane and nitrogen ice ”

See the image here:

It described the image as ”Pluto’s surface is marked with cracks and craters in shades of brown. The partially visible heart appears in the lower right of the small world, which is surrounded by black space.⁣”

New Horizons launched in January 2006 and reached Pluto in July 2015, flying within 7,800 miles of its surface, and becoming the first probe to fly by Pluto and its moons. The far-traveling spacecraft also visited a distant Kuiper Belt object Ultima Thule (2014 MU69) in January 2019. 

Instagram users loved the picture and shared a variety of comments.  One user wrote, ”Wouahh what a great capture, thanks to New Horizon spacecraft.” Another commented, ”For me, Pluto will always be a planet.” 

A third said, ”Why is Pluto, not a plane? it literally has a heart!” A fourth added, ”Being afar doesn’t mean you aren’t part of the family.”

Pluto was once considered the ninth planet in the solar system, however, it was demoted in 2006 and reclassified as a dwarf planet. The International Astronomical Union (IAU) downgraded the status of Pluto to that of a dwarf planet because it did not meet the three criteria the IAU uses to define a full-sized planet.

Pluto is slightly over 1,400 miles (2250 km) wide or about half the breadth of the United States or two-thirds the width of the Moon. With its average temperature of -387F (-232C) – Pluto’s surface is coated in ice made of water, methane, and nitrogen and is believed to have a rocky core and possibly a deep ocean. 

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This Week @NASA: Private Astronaut Mission, Autonomous Snake-Like Robot Explorer, TROPICS Launch – SciTechDaily



Illustration of the Exobiology Extant Life Surveyor (EELS) concept. Credit NASA/JPL-CalTech

The second all-private astronaut mission to the space station …


Completing the set of tiny severe weather trackers …

And a robotic explorer – with a twist …

A few of the stories to tell you about – This Week at <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is &quot;To discover and expand knowledge for the benefit of humanity.&quot; Its core values are &quot;safety, integrity, teamwork, excellence, and inclusion.&quot; NASA conducts research, develops technology and launches missions to explore and study Earth, the solar system, and the universe beyond. It also works to advance the state of knowledge in a wide range of scientific fields, including Earth and space science, planetary science, astrophysics, and heliophysics, and it collaborates with private companies and international partners to achieve its goals.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>NASA!

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Second Private Astronaut Mission to the Space Station

On May 21, a <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Commonly known as SpaceX, Space Exploration Technologies Corp. is a private American aerospace manufacturer and space transport services company that was founded by Elon Musk in 2002. Headquartered in Hawthorne, California, the company designs, manufactures, and launches advanced rockets and spacecraft. SpaceX's ultimate goal is to reduce space transportation costs and enable the colonization of Mars.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>SpaceX Dragon spacecraft launched from NASA’s Kennedy Space Center on Axiom Mission 2, the second all private astronaut mission to the International Space Station.

The four-person crew, commanded by former NASA astronaut Peggy Whitson, is scheduled to spend several days conducting research, outreach, and commercial activities on the space station.

Rocket Lab TROPICS CubeSats

Rocket Lab’s Electron rocket lifts off from Launch Complex 1 at Māhia, New Zealand at 11:46 a.m, on May 25, 2023, carrying two TROPICS CubeSats for NASA. Credit: Rocket Lab

Final Pair of Storm-Observing CubeSats Launched

The final two CubeSats for NASA’s TROPICS mission launched from Rocket Lab’s Launch Complex 1 in New Zealand on May 26. The small satellites will join two other identical spacecraft that launched to orbit earlier this month.

All four will fly, as a constellation, in a unique low Earth orbit that will allow them to observe tropical cyclones, including hurricanes and typhoons, more often than what is possible with
current weather satellites.

Snake Robot EELS at Ski Resort

Team members from JPL test a snake robot called EELS at a ski resort in the Southern California mountains in February. Designed to sense its environment, calculate risk, travel, and gather data without real-time human input, EELS could eventually explore destinations throughout the solar system. Credit: NASA/JPL-Caltech

Autonomous Snake-Like Robotic Explorer

A team at NASA’s Jet Propulsion Laboratory is creating and testing a snake-like robot called EELS, short for Exobiology Extant Life Surveyor. The self-propelled, autonomous robot is
being developed to go where other robots can’t go.

Although it was inspired by a desire to look for signs of life in the sub-surface ocean on <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Saturn is the sixth planet from the sun and has the second-largest mass in the Solar System. It has a much lower density than Earth but has a much greater volume. Saturn's name comes from the Roman god of wealth and agriculture.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>Saturn’s icy moon, Enceladus, EELS is not currently part of any NASA mission.

Hot Fire RS-25 Certification Engine

NASA completed a crucial hot fire test of the RS-25 engine, part of a 12-test certification series for future Artemis missions. This achievement brings NASA one step closer to landing the first woman and person of color on the Moon, as well as establishing a long-term lunar presence. Credit: NASA / Stennis

Artemis Rocket Engine Test Series Continues

On May 23, NASA’s Stennis Space Center conducted a hot fire test of an RS-25 rocket engine. It was the eighth hot fire of the current 12-test series to certify production of new RS-25s.

Four of the engines will help power NASA’s Space Launch System rocket on future Artemis missions to the Moon.

That’s what’s up this week @NASA.

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