Connect with us

Science

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

Published

 on


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:

[embedded content]

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:

[embedded content]

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.

Let’s block ads! (Why?)



Source link

Continue Reading

Science

New species of crested dinosaur identified in Mexico

Published

 on

A team of palaeontologists in Mexico have identified a new species of dinosaur after finding its 72 million-year-old fossilized remains almost a decade ago, Mexico’s National Institute of Anthropology and History (INAH) said on Thursday.

The new species, named Tlatolophus galorum, was identified as a crested dinosaur after 80% of its skull was recovered, allowing experts to compare it to other dinosaurs of that type, INAH said.

The investigation, which also included specialists from the National Autonomous University of Mexico, began in 2013 with the discovery of an articulated tail in the north-central Mexican state of Coahuila, where other discoveries have been made.

“Once we recovered the tail, we continued digging below where it was located. The surprise was that we began to find bones such as the femur, the scapula and other elements,” said Alejandro Ramírez, a scientist involved in the discovery.

Later, the scientists were able to collect, clean and analyze other bone fragments from the front part of the dinosaur’s body.

The palaeontologists had in their possession the crest of the dinosaur, which was 1.32 meters long, as well as other parts of the skull: lower and upper jaws, palate and even a part known as the neurocranium, where the brain was housed, INAH said.

The Mexican anthropology body also explained the meaning of the name – Tlatolophus galorum – for the new species of dinosaur.

Tlatolophus is a mixture of two words, putting together a term from the indigenous Mexican language of Nahuatl that means “word” with the Greek term meaning “crest”. Galorum refers to the people linked to the research, INAH said.

 

(Reporting by Abraham Gonzalez; Writing by Drazen Jorgic; Editing by Ana Nicolaci da Costa)

Continue Reading

Science

Alberta family searches for answers in teen's sudden death after COVID exposure, negative tests – CBC.ca

Published

 on


A southern Alberta mother and father are grappling with the sudden, unexplained death of their 17-year-old daughter, and with few answers, they’re left wondering if she could be the province’s youngest victim of COVID-19.

Sarah Strate — a healthy, active Grade 12 student at Magrath High School who loved singing, dancing and being outdoors — died on Monday, less than a week after being notified she’d been exposed to COVID-19.

While two tests came back negative, her parents say other signs point to the coronavirus, and they’re waiting for more answers. 

“It was so fast. It’s all still such a shock,” said Sarah’s mother, Kristine Strate. “She never even coughed. She had a sore throat and her ears were sore for a while, and [she had] swollen neck glands.”

Kristine said Sarah developed mild symptoms shortly after her older sister — who later tested positive for COVID-19 —  visited from Lethbridge, one of Alberta’s current hot spots for the virus.

The family went into isolation at their home in Magrath on Tuesday, April 20. They were swabbed the next day and the results were negative.

‘Everything went south, super-fast’

By Friday night, Sarah had developed fever and chills. On Saturday, she started vomiting and Kristine, a public health nurse, tried to keep her hydrated.

“She woke up feeling a bit more off on Monday morning,” Kristine said. “And everything went south, super-fast.”

Sarah had grown very weak and her parents decided to call 911 when she appeared to become delirious.

“She had her blanket on and I was talking to her and, in an instant, she was unresponsive,” said Kristine, who immediately started performing CPR on her daughter.

When paramedics arrived 20 minutes later, they were able to restore a heartbeat and rushed Sarah to hospital in Lethbridge, where she died.

“I thought there was hope once we got her heart rate back. I really did,” recalled Sarah’s father, Ron.

“He was praying for a miracle, and sometimes miracles don’t come,” said Kristine.

Strate’s parents say her health deteriorated quickly after being exposed to COVID-19. She died at Chinook Regional Hospital in Lethbridge on Monday. (Ron Strate)

Searching for answers

At the hospital, the family was told Sarah’s lungs were severely infected and that she may have ended up with blood clots in both her heart and lungs, a condition that can be a complication of COVID-19.

But a second test at the hospital came back negative for COVID-19.

“There really is no other answer,” Ron said. “When a healthy 17-year-old girl, who was sitting up in her bed and was able to talk, and within 10 minutes is unconscious on our floor — there was no reason [for it].”

The province currently has no record of any Albertans under the age of 20 who have died of COVID-19.

According to the Strate family, the medical examiner is running additional blood and tissue tests, in an effort to uncover the cause of Sarah’s death.

‘Unusual but not impossible’

University of Alberta infectious disease specialist Dr. Lynora Saxinger, who was not involved in Sarah’s treatment, says it is conceivable that further testing could uncover evidence of a COVID-19 infection, despite two negative test results.

However, she hasn’t seen a similar case in Alberta.

“It would be unusual but not impossible because no test is perfect. We have had cases where an initial test is negative and then if you keep on thinking it’s COVID and you re-test, you then can find COVID,” she said.

According to Saxinger, the rate of false negatives is believed to be very low. But it can happen if there are problems with the testing or specimen collection.

She says people are more likely to test positive after symptoms develop. 

“The best sensitivity of the test is around day four or five of having symptoms,” she said. “So you can miss things if you test very, very early. And with new development of symptoms, it’s always a good time to re-test because then the likelihood of getting a positive test is a little higher. But again, no test is perfect.” 

Sarah deteriorated so quickly — dying five days after she first developed symptoms — she didn’t live long enough to make it to her follow-up COVID-19 test. Instead, it was done at the hospital.

‘An amazing kid’

The Strate family now faces an agonizing wait for answers — one that will likely take months — about what caused Sarah’s death.

But Ron, who teaches at the school where Sarah attended Grade 12, wants his daughter to be remembered for the life she lived, not her death.

Strate, pictured here at three years old, had plans to become a massage therapist. She attended Grade 12 at Magrath High School and was an active, healthy teenager who was involved in sports, music and the school’s suicide prevention group. (Ron Strate)

Sarah was one of five children. Ron says she was strong, active and vibrant and had plans to become a massage therapist after graduating from high school.

She played several sports and loved to sing and dance as part of a show choir. She was a leader in the school’s suicide prevention group and would stand up for other students who were facing bullying.

“She’s one of the leaders in our Hope Squad … which goes out and helps kids to not be scared,” he father said.

“She’s an amazing kid.”

Sarah would often spend hours helping struggling classmates, and her parents hope her kindness is not forgotten.

“She’d done so many good things. Honestly, I’ve got so many messages from parents saying, ‘You have no idea how much your daughter helped our kid,'” said Ron.

“This 17-year-old girl probably lived more of a life in 17 years than most adults will live in their whole lives. She was so special. I love her so much.”

Let’s block ads! (Why?)



Source link

Continue Reading

Science

China launches key module of space station planned for 2022

Published

 on

BEIJING (Reuters) -China launched an unmanned module on Thursday containing what will become living quarters for three crew on a permanent space station that it plans to complete by the end of 2022, state media reported.

The module, named “Tianhe”, or “Harmony of the Heavens”, was launched on the Long March 5B, China’s largest carrier rocket, at 11:23 a.m. (0323 GMT) from the Wenchang Space Launch Centre on the southern island of Hainan.

Tianhe is one of three main components of what would be China’s first self-developed space station, rivalling the only other station in service – the International Space Station (ISS).

The ISS is backed by the United States, Russia, Europe, Japan and Canada. China was barred from participating by the United States.

“(Tianhe) is an important pilot project in the building of a powerful nation in both technology and in space,” state media quoted President Xi Jinping as saying in a congratulatory speech.

Tianhe forms the main living quarters for three crew members in the Chinese space station, which will have a life span of at least 10 years.

The Tianhe launch was the first of 11 missions needed to complete the space station, which will orbit Earth at an altitude of 340 to 450 km (211-280 miles).

In the later missions, China will launch the two other core modules, four manned spacecraft and four cargo spacecraft.

Work on the space station programme began a decade ago with the launch of a space lab Tiangong-1 in 2011, and later, Tiangong-2 in 2016.

Both helped China test the programme’s space rendezvous and docking capabilities.

China aims to become a major space power by 2030. It has ramped up its space programme with visits to the moon, the launch of an uncrewed probe to Mars and the construction of its own space station.

In contrast, the fate of the ageing ISS – in orbit for more than two decades – remains uncertain.

The project is set to expire in 2024, barring funding from its partners. Russia said this month that it would quit the project from 2025.

Russia is deepening ties with China in space as tensions with Washington rise.

Moscow has slammed the U.S.-led Artemis moon exploration programme and instead chosen to join Beijing in setting up a lunar research outpost in the coming years.

(Reporting by Ryan Woo and Liangping Gao; Editing by Christian Schmollinger, Simon Cameron-Moore and Lincoln Feast.)

Continue Reading

Trending