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NASA uncovers hidden system of mysteriously draining lakes under Antarctica – Livescience.com

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Scientists have discovered two new lakes buried deep beneath the Antarctic Ice Sheet. 

These hidden gems of frigid water are part of a vast network of ever-changing lakes hidden beneath 1.2 to 2.5 miles (2 to 4 kilometers) of ice on the southernmost continent. These lakes fill and drain over and over again in largely mysterious cycles that may influence how fast the ice sheet moves and how and where meltwater reaches the Southern Ocean. This flow, in turn, can change the currents in the Southern Ocean and potentially affect ocean circulation worldwide. 

“It’s not just the ice sheet we’re talking about,” study leader Matthew Siegfried, a geophysicist at the Colorado School of Mines, said in a statement. “We’re really talking about a water system that is connected to the whole Earth system.”

 Related: Photos of Antarctica: The ice-covered bottom of the world 

Hidden water

The lakes sit at the bottom of the ice sheet, where the ice meets the rocky Antarctic continent. Unlike in Greenland, where meltwater flows from the ice surface through crevasses and holes called moulins, Antarctica’s lakes form from beneath the ice, probably as a result of pressure, friction and perhaps geothermal heat. 

This water system was largely invisible until the advent of NASA’s ICESat mission in 2003. The ICESat satellite used lasers to precisely measure the elevation of Antarctic ice. In 2007, Scripps Institution of Oceanography glaciologist Helen Amanda Fricker connected the elevation changes measured by ICESat to the dynamics of the lakes deep beneath the ice surface. As the lakes drain and fill, the ice above rises and falls, offering hints as to what’s happening below. 

Fricker’s breakthrough opened up the possibility of tracking the lake system over time. ICESat, however, collected data for only six years. Its European Space Agency equivalent, CryoSat-2, collected similar data starting in 2010 but over a broader area and with less precision. In September 2018, NASA launched a new satellite, ICESat-2, which collects the highest-precision data yet. 

“ICESat-2 is like putting on your glasses after using ICESat: The data are such high precision that we can really start to map out the lake boundaries on the surface,” Siegfried said. 

A dynamic system

In the new study, Siegfried and Fricker combined data from ICESat, CryoSat-2 and ICESat-2 to trace changes in the subglacial lake system from October 2003 to July 2020. They focused on three areas with good satellite coverage and known active lakes: the boundary between the Mercer and Whillans ice streams in West Antarctica; the lower MacAyeal Ice Stream, also in West Antarctica; and the upper Academy Glacier in East Antarctica. 

At the Mercer and Whillans boundary, the researchers found two new lakes, which they dubbed the Lower Conway Subglacial Lake and the Lower Mercer Subglacial Lake. They also found that what was thought to be one lake under the MacAyeal ice stream was actually two. 

Over time, these lakes experienced major change. The lakes beneath the Mercer and Whillans ice stream boundary are currently undergoing their third period of drainage in 17 years. Meanwhile, all of the lakes beneath the MacAyeal ice stream have followed their own patterns of draining and filling. The lowermost lake went through four fill-drain events during the study period, each taking only about a year to complete. The second lake drained between 2014 and 2015 and is currently filling up again, while the third lake drained just slightly between 2016 and 2017. Meanwhile, the lakes beneath Academy Glacier drained between 2009 and 2018. 

All of these changes are puzzle pieces in scientists’ understanding of the speed and direction of Antarctica’s ice sheet flow. Already, researchers are finding the links between the under-ice lakes and the ocean: In January, a study co-authored by Fricker found that the drainage of one lake on the Amery Ice Shelf in East Antarctica flushed as much as 198 billion gallons (750 billion liters) into the ocean in only three days, Live Science reported at the time.

The new study was published July 7 in the journal Geophysical Research Letters.

Originally published on Live Science

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.

Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.

She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.

Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.

“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.

It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.

Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.

Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.

Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.

“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.

He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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B.C. sets up a panel on bear deaths, will review conservation officer training

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VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

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