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Climate change: The ice we’ve lost this decade, visualized – Vox.com

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One of the most poignant climate moments of 2019 was a funeral for ice: an August ceremony in Iceland for the country’s Okjökull glacier. As can be seen in these NASA satellite images, the glacier declined dramatically between 1986 and 2019:

The Ok glacier in Iceland lost its designation as a glacier in 2014 and was mourned over the summer this year.
Nasa Earth Observatory and NASA Earth Observatory

Mourners remembered the once-large patch of ice with a plaque.

“In the next 200 years all our glaciers are expected to follow the same path,” the plaque reads. “This monument is to acknowledge that we know what is happening and what needs to be done. Only you will know if we did it.”

The loss of Okjökull (officially stripped of its glacier status in 2014) was one of many deeply troubling milestones this decade in the world’s frozen regions, known collectively as the cryosphere. The Arctic in particular is warming twice as fast as the global average and experienced many historic heat waves. The warming, in turn, is causing an unprecedented amount of melt in the world’s ice.

The ice sheets on land have critical effects on seawater levels around the world. If all the ice on Greenland were to melt, it would raise global sea levels by 20 feet. If all the ice in Antarctica melted, it would raise sea levels by 190 feet.

That’s just for ice on land. The melt of once-frozen waters is threatening vulnerable species, changing circulation patterns in the ocean, and fueling feedback loops that could cause even more ice to melt.

In this post, we’ll walk through some of the key markers of climate change in the polar regions this decade with visuals, as well as some of the key insights we gained. (We’ve omitted Greenland’s ice sheet only because there aren’t many good images available.) We learned that ice is declining at both poles at an accelerating rate the world hasn’t seen in centuries. We can now see these dramatic changes from space. And we have a much better grasp on what we’ll lose if we don’t slow the emissions destabilizing the global climate.

There are two main categories of ice in the cryosphere. One is the ice that forms on land from precipitation: Two-thirds of the planet’s freshwater is frozen in these ice caps, sheets, and glaciers. The other is the ice that forms from freezing the ocean, known as sea ice.

The extent of sea ice tends to ebb and flow with the seasons, but over the past decade, both the highs and lows have gotten lower.

“If you look at just the last decade, 2010 to 2019, eight out of those 10 years are among the lowest 10,” said Walt Meier, a senior research scientist at the National Snow and Ice Data Center.

You can see that in this graph comparing the extent of Arctic sea ice over the course of a year. It grows in the winter and shrinks in the summer, but in recent years, there’s less of the former and more of the latter.

Christina Animashaun/Vox

The record low was in 2012, but this year isn’t much farther behind. “It’s kind of reinforcing that we’re heading on a downward trend,” Meier said.

But the picture is more bleak when we zoom out to a longer time scale: We are currently in the midst of the fastest decline of Arctic sea ice in 1,500 years.

Christina Animashaun/Vox

And you can see how this has played out in recent decades in this time lapse animation of ice at the North Pole:

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But Meier notes that it’s not just the extent of sea ice that’s changing; the thickness is shrinking as well. It’s a key factor in how much ice survives the summer and how quickly it can regrow in the winter, and we’ve only recently gained a good handle on this with new satellite instruments that can track thickness over time. “The thickness is decreasing as rapidly or more rapidly than the extent,” he said.

The planet’s South Pole is one of its coldest regions, and it’s warming up as well, prompting the rate of ice melt to accelerate. In the past decade, the rate of ice melt in Antarctica tripled compared to 2007. This is on pace to cause six inches of sea level rise by 2100.

Melting ice in Antarctica

Ice melt in Antarctica has accelerated in the past decade.
Javier Zarracina/Vox

You can see some of these dramatic changes playing out in sections of Antarctica, like the Pine Island Glacier. Here is an animation showing the retreat of the glacier since 2000.

The decline of Antarctica’s Pine Island Glacier since 2000.
The decline of Antarctica’s Pine Island Glacier since 2000.

The decline of Antarctica’s Pine Island Glacier since 2000.
NASA Earth Observatory

The trends in ice in Antarctica are a bit more complicated. There are sections of the Antarctic ice sheet where ice is growing in depth, and others where it is declining, as can be seen in this NASA visual looking at the last 25 years:

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Currently, the East Antarctic Ice Sheet, the larger, thicker, cooler, more stable sheet in Antarctica, is unlikely to see major changes in the coming years. But the West Antarctic Ice Sheet is showing signs of an accelerating rate of melt, driven in part by climate change.

Greenhouse gas emissions, meanwhile, climbed ever higher this decade. In 2010, carbon dioxide concentrations peaked at 394 parts per million (ppm), according to observations at the Mauna Loa Observatory. This year, the observatory reported a record high of 414.8 ppm, a concentration not seen on Earth for millions of years.

“At our current rates of increasing emissions, it’s pretty inevitable we’re going to have ice-free summer conditions at some point in the future, probably within the next, three decades,” Meier said. “It’s a matter of ‘when,’ not ‘if’ anymore.”

However, there is uncertainty in how many summers we’ll see without ice in the Arctic, and a key source of that uncertainty is what we’ll do about our greenhouse gas emissions.

The Paris climate agreement set out to limit warming this century to less than 2 degrees Celsius above pre-industrial levels, with a more ambitious target of staying below 1.5 degrees Celsius. Hitting the latter target would require halving global emissions by as soon as 2030, reaching net-zero emissions by 2050, and then net reductions of carbon dioxide in the atmosphere thereafter.

It’s a tall order, but reaching the more-ambitious goal would mean more ice would survive the summer. “In 2 degrees [Celsius] of warming, which is the target set in Paris, it’s likely that we’ll have ice-free summers pretty regularly under those conditions,” Meier said. “But if we hold things to 1.5 degrees [Celsius], which is kind of the ambitious goal, I’m not sure how realistic that is, we’ll likely keep a fair amount of ice around the summer.”

So we’ll likely lose even more from the coldest parts of the world in the coming decade. But the actions we all take will shape just how much is lost.

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Las Vegas Aces Rookie Kate Martin Suffers Ankle Injury in Game Against Chicago Sky

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Las Vegas Aces rookie Kate Martin had to be helped off the floor and taken to the locker room after suffering an apparent ankle injury in the first quarter of Tuesday night’s game against the Chicago Sky.

Late in the first quarter, Martin was pushing the ball up the court when she appeared to twist her ankle and lost her balance. The rookie was in serious pain, lying on the floor before eventually being helped off. Her entire team came out in support, and although she managed to put some pressure on the leg, she was taken to the locker room for further evaluation.

Martin returned to the team’s bench late in the second quarter but was ruled out for the remainder of the game.

“Kate Martin is awesome. Kate Martin picks up things so quickly, she’s an amazing sponge,” Aces guard Kelsey Plum said of the rookie during the preseason. “I think (coach) Becky (Hammon) nicknamed her Kate ‘Money’ Martin. I think that’s gonna stick. And when I say ‘money,’ it’s not just about scoring and stuff, she’s just in the right place at the right time. She just makes people better. And that’s what Becky values, that’s what our coaching staff values and that’s why she’s gonna be a great asset to our team.”

Las Vegas selected Martin in the second round of the 2024 WNBA Draft. She was coming off the best season of her collegiate career at Iowa, where she averaged 13.1 points, 6.8 rebounds, and 2.3 assists per game during the 2023-24 campaign. Martin’s integration into the Aces organization has been seamless, with her quickly earning the respect and admiration of her teammates and coaches.

The team and fans alike are hoping for a speedy recovery for Martin, whose contributions have been vital to the Aces’ performance this season.

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Asteroid Apophis will visit Earth in 2029, and this European satellite will be along for the ride

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The European Space Agency is fast-tracking a new mission called Ramses, which will fly to near-Earth asteroid 99942 Apophis and join the space rock in 2029 when it comes very close to our planet — closer even than the region where geosynchronous satellites sit.

Ramses is short for Rapid Apophis Mission for Space Safety and, as its name suggests, is the next phase in humanity’s efforts to learn more about near-Earth asteroids (NEOs) and how we might deflect them should one ever be discovered on a collision course with planet Earth.

In order to launch in time to rendezvous with Apophis in February 2029, scientists at the European Space Agency have been given permission to start planning Ramses even before the multinational space agency officially adopts the mission. The sanctioning and appropriation of funding for the Ramses mission will hopefully take place at ESA’s Ministerial Council meeting (involving representatives from each of ESA’s member states) in November of 2025. To arrive at Apophis in February 2029, launch would have to take place in April 2028, the agency says.

This is a big deal because large asteroids don’t come this close to Earth very often. It is thus scientifically precious that, on April 13, 2029, Apophis will pass within 19,794 miles (31,860 kilometers) of Earth. For comparison, geosynchronous orbit is 22,236 miles (35,786 km) above Earth’s surface. Such close fly-bys by asteroids hundreds of meters across (Apophis is about 1,230 feet, or 375 meters, across) only occur on average once every 5,000 to 10,000 years. Miss this one, and we’ve got a long time to wait for the next.

When Apophis was discovered in 2004, it was for a short time the most dangerous asteroid known, being classified as having the potential to impact with Earth possibly in 2029, 2036, or 2068. Should an asteroid of its size strike Earth, it could gouge out a crater several kilometers across and devastate a country with shock waves, flash heating and earth tremors. If it crashed down in the ocean, it could send a towering tsunami to devastate coastlines in multiple countries.

Over time, as our knowledge of Apophis’ orbit became more refined, however, the risk of impact  greatly went down. Radar observations of the asteroid in March of 2021 reduced the uncertainty in Apophis’ orbit from hundreds of kilometers to just a few kilometers, finally removing any lingering worries about an impact — at least for the next 100 years. (Beyond 100 years, asteroid orbits can become too unpredictable to plot with any accuracy, but there’s currently no suggestion that an impact will occur after 100 years.) So, Earth is expected to be perfectly safe in 2029 when Apophis comes through. Still, scientists want to see how Apophis responds by coming so close to Earth and entering our planet’s gravitational field.

“There is still so much we have yet to learn about asteroids but, until now, we have had to travel deep into the solar system to study them and perform experiments ourselves to interact with their surface,” said Patrick Michel, who is the Director of Research at CNRS at Observatoire de la Côte d’Azur in Nice, France, in a statement. “Nature is bringing one to us and conducting the experiment itself. All we need to do is watch as Apophis is stretched and squeezed by strong tidal forces that may trigger landslides and other disturbances and reveal new material from beneath the surface.”

The Goldstone radar’s imagery of asteroid 99942 Apophis as it made its closest approach to Earth, in March 2021. (Image credit: NASA/JPL–Caltech/NSF/AUI/GBO)

By arriving at Apophis before the asteroid’s close encounter with Earth, and sticking with it throughout the flyby and beyond, Ramses will be in prime position to conduct before-and-after surveys to see how Apophis reacts to Earth. By looking for disturbances Earth’s gravitational tidal forces trigger on the asteroid’s surface, Ramses will be able to learn about Apophis’ internal structure, density, porosity and composition, all of which are characteristics that we would need to first understand before considering how best to deflect a similar asteroid were one ever found to be on a collision course with our world.

Besides assisting in protecting Earth, learning about Apophis will give scientists further insights into how similar asteroids formed in the early solar system, and, in the process, how  planets (including Earth) formed out of the same material.

One way we already know Earth will affect Apophis is by changing its orbit. Currently, Apophis is categorized as an Aten-type asteroid, which is what we call the class of near-Earth objects that have a shorter orbit around the sun than Earth does. Apophis currently gets as far as 0.92 astronomical units (137.6 million km, or 85.5 million miles) from the sun. However, our planet will give Apophis a gravitational nudge that will enlarge its orbit to 1.1 astronomical units (164.6 million km, or 102 million miles), such that its orbital period becomes longer than Earth’s.

It will then be classed as an Apollo-type asteroid.

Ramses won’t be alone in tracking Apophis. NASA has repurposed their OSIRIS-REx mission, which returned a sample from another near-Earth asteroid, 101955 Bennu, in 2023. However, the spacecraft, renamed OSIRIS-APEX (Apophis Explorer), won’t arrive at the asteroid until April 23, 2029, ten days after the close encounter with Earth. OSIRIS-APEX will initially perform a flyby of Apophis at a distance of about 2,500 miles (4,000 km) from the object, then return in June that year to settle into orbit around Apophis for an 18-month mission.

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Furthermore, the European Space Agency still plans on launching its Hera spacecraft in October 2024 to follow-up on the DART mission to the double asteroid Didymos and Dimorphos. DART impacted the latter in a test of kinetic impactor capabilities for potentially changing a hazardous asteroid’s orbit around our planet. Hera will survey the binary asteroid system and observe the crater made by DART’s sacrifice to gain a better understanding of Dimorphos’ structure and composition post-impact, so that we can place the results in context.

The more near-Earth asteroids like Dimorphos and Apophis that we study, the greater that context becomes. Perhaps, one day, the understanding that we have gained from these missions will indeed save our planet.

 

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McMaster Astronomy grad student takes a star turn in Killarney Provincial Park

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Astronomy PhD candidate Veronika Dornan served as the astronomer in residence at Killarney Provincial Park. She’ll be back again in October when the nights are longer (and bug free). Dornan has delivered dozens of talks and shows at the W.J. McCallion Planetarium and in the community. (Photos by Veronika Dornan)

Veronika Dornan followed up the April 8 total solar eclipse with another awe-inspiring celestial moment.

This time, the astronomy PhD candidate wasn’t cheering alongside thousands of people at McMaster — she was alone with a telescope in the heart of Killarney Provincial Park just before midnight.

Dornan had the park’s telescope pointed at one of the hundreds of globular star clusters that make up the Milky Way. She was seeing light from thousands of stars that had travelled more than 10,000 years to reach the Earth.

This time there was no cheering: All she could say was a quiet “wow”.

Dornan drove five hours north to spend a week at Killarney Park as the astronomer in residence. part of an outreach program run by the park in collaboration with the Allan I. Carswell Observatory at York University.

Dornan applied because the program combines her two favourite things — astronomy and the great outdoors. While she’s a lifelong camper, hiker and canoeist, it was her first trip to Killarney.

Bruce Waters, who’s taught astronomy to the public since 1981 and co-founded Stars over Killarney, warned Dornan that once she went to the park, she wouldn’t want to go anywhere else.

The park lived up to the hype. Everywhere she looked was like a painting, something “a certain Group of Seven had already thought many times over.”

The dome telescopes at Killarney Provincial Park.

She spent her days hiking the Granite Ridge, Crack and Chikanishing trails and kayaking on George Lake.  At night, she went stargazing with campers — or at least tried to. The weather didn’t cooperate most evenings — instead of looking through the park’s two domed telescopes, Dornan improvised and gave talks in the amphitheatre beneath cloudy skies.

Dornan has delivered dozens of talks over the years in McMaster’s W.J. McCallion Planetarium and out in the community, but “it’s a bit more complicated when you’re talking about the stars while at the same time fighting for your life against swarms of bugs.”

When the campers called it a night and the clouds parted, Dornan spent hours observing the stars. “I seriously messed up my sleep schedule.”

She also gave astrophotography a try during her residency, capturing images of the Ring Nebula and the Great Hercules Cluster.

A star cluster image by Veronika Dornan

“People assume astronomers take their own photos. I needed quite a lot of guidance for how to take the images. It took a while to fiddle with the image properties, but I got my images.”

Dornan’s been invited back for another week-long residency in bug-free October, when longer nights offer more opportunities to explore and photograph the final frontier.

She’s aiming to defend her PhD thesis early next summer, then build a career that continues to combine research and outreach.

“Research leads to new discoveries which gives you exciting things to talk about. And if you’re not connecting with the public then what’s the point of doing research?”

 

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