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Seeing the Greenland Ice Sheet Through Students' Eyes – Eos

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From 1926 to 1928, William Herbert Hobbs, a professor at the University of Michigan, led a series of three annual scientific expeditions to Greenland. Hobbs and his colleagues on these missions collected some of the earliest geophysical and atmospheric measurements in this region, including the first documentation of gravity-driven katabatic winds, which carry cool, dense air masses down solid slopes like ice sheets or hillsides and which earned Greenland the title of “north pole of the winds.”

Almost a century later, in June 2019, four faculty members (including P.S., M.F., and J.B.) led a team of undergraduate students (including C.S., L.G., and A.M.) from the University of Michigan, the University at Albany in New York, the Virginia Polytechnic Institute and State University, and the University of Monterrey in Mexico on a 10-day field expedition to Greenland to repeat some of Hobbs’s original work. The trip provided the students with field experience and practice in collecting measurements relevant to the meteorology and climate of Greenland.

The 2019 expedition was also focused on introducing a diverse cohort of young researchers to polar science and on exploring the effects of climate change experienced by Greenlandic residents. Hobbs’s expedition teams were all male; glaciology did not include women in those days. In contrast, the 13 students in the 2019 group represented different genders, ages, socioeconomic backgrounds, educations, and international experiences. Of this group, seven students identified as female, and one student identified as nonbinary. Although we came from diverse backgrounds, we were united in our passion for studying climate change and the environment.

An Arctic Adventure Begins

The journey began in Albany, N.Y., where we spent 3 days completing instrumentation training and logistical planning and getting to know the people with whom we would be sharing this unique experience. During this time, the faculty leaders introduced important environmental concepts that would be important for the trip. With this information, it was the students’ task to create a plan for when we were in the field and detail what types of measurements we wanted to take and where.

After this initial training and with all the equipment packed, we made our way to Stratton Air National Guard Base in nearby Schenectady, N.Y., where we boarded a C-130 military transport plane and departed for Kangerlussuaq Airport in western Greenland.

We were undeniably excited, but we were also nervous about the journey. For many of us, this would mark the first time we voyaged into the Arctic Circle, embarked on an international trip, or, for one student, even caught a glimpse of snow. This same feeling resonated with the professors, who were concerned about the safety and well-being of the participants.

Window real estate on the plane was limited, and the aircraft was crowded with various research groups, making it difficult to move about in the space. The cramped flight was worth it, though, when we saw our first glimpse of Greenland, the icy Arctic landscape painted in various shades of blue. We also saw large melt lakes that served as a reminder of the extreme melt season underway. It was at this moment that our group could truly visualize the devastating impacts of climate change on this landscape.

Glacial melt lakes were visible from the window of the C-130 transport plane that brought the group to Greenland. Credit: Mark Flanner

After arriving at Kangerlussuaq, we had only 10 days to fulfill the objectives of our expedition, so our day-to-day schedule was busy. We learned quickly that pursuing field experiments requires flexibility, especially with large groups. In a couple of instances, we changed plans because of the weather, and at other times we adjusted our schedule to attend presentations given by the local community.

We spent much of our time setting up field experiments that we would later conduct on and around the Greenland Ice Sheet. For example, we took the opportunity to launch a weather balloon close to our camp to capture data about wind circulation along the ice sheet.

The face of the ice sheet was visible from the top of Black Ridge, located near the Kangerlussuaq International Science Support (KISS) building, our base of operations, but we couldn’t fully appreciate the vastness of the ice until we trekked up a portion of Russell Glacier.

The ice-covered landscape was surrounded by sandy glacial deposits, home to a myriad of minerals, including garnet gems. Instead of the crisp, white snow typically depicted in museum paintings of snowcapped mountains or icy landscapes, we saw a glacier covered in dark layers of earth dug up as the ice moved. This image would become familiar after multiple hikes back to the glacier’s towering calving front.

Listening to the Glacier

When we first arrived at the calving front on an overnight field excursion, it was apparent that fragments of the glacier had fallen into the river below. The remoteness of the region and the lack of sound pollution allowed us to listen to the acoustic crackling deep within the glaciers. We wondered if more ice would soon break free, so we set up a camera overnight, hoping to record what we suspected would be a large calving event on one section of the ice.

We mounted the camera between two small rocks to protect it from strong wind gusts and looked forward to returning the next day. When we returned, it was obvious that part of the glacier face had indeed calved, but the camera had stopped recording after a few hours and missed the event. Fortunately, the river flow instrument we had also left at the site caught the change in water height when the calving event occurred. Seeing firsthand how quickly changes to the glacier face could occur reiterated how fast these seemingly permanent structures can break apart and disappear.

A partial collapse along the edge of Greenland’s Russell Glacier is apparent in this photo. Credit: Chelsea E. Snide

After our return from the overnight expedition near Russell Glacier, we flew on a C-130 to Summit Station at the center of the Greenland Ice Sheet. Although our visit to the research station lasted only an hour, it significantly affected us all. The endless expanse of ice and drifting snow seemed to belong to a world other than the one in Kangerlussuaq.

At Summit Station, we saw a grid of poles—set up by researchers conducting snow accumulation experiments to prevent confusion in whiteout conditions—marking paths to different locations. In the Big House, the main structure of Summit Station, we learned about living and working conditions at the station, including the fact that during winter, typically, only a few people are in residence and food supplies can run short. Despite the difficult circumstances there, several of us left inspired to one day return to pursue research at Summit Station.

Learning by Doing

An important aspect of the expedition was for the undergraduate students to learn necessary skills for designing and executing successful research projects. During the campaign, our team measured surface energy flux and stream flow on and around the Greenland Ice Sheet, and we collected upper air radiosonde data on pressure, temperature, dew point, and wind speed and direction. The students used drones to learn about remote sensing practices, and we collected topographic data to create a 3-D map of Russell Glacier that will help in monitoring ice loss in our changing climate.

A lasting outcome of the trip was our installation of an air quality sensor, attached to the Danish meteorological station outside Kangerlussuaq, for real-time monitoring using the PurpleAir network. The sensor captured elevated particulate matter levels during the Greenland fires that broke out 2 weeks after our expedition.

This effort is the start of obtaining a long-term data set of aerosol particulate concentrations in this remote location—data that will be used to monitor how aerosols are transported to Greenland and their associated impacts on air quality and ice melting.

To commemorate the original Hobbs expeditions and contrast techniques of old and modern remote sensing capabilities, we also launched several pilot balloons similar to the ones used on Hobbs’s expedition and tracked their trajectories with a theodolite (a telescope-like surveying tool used to measure horizontal and vertical angles).

Like the scientists on William Herbert Hobbs’s 1926 expedition, students on the Greenland trip last June used a theodolite to track the trajectories of pilot balloons. Credit: Mark Flanner

A Lasting Impact

Events in Greenland (which is served by only two commercial airlines) remain largely unnoticed by the rest of the world. But the reality of climate change and its effects on this remote land became particularly apparent through our conversations with local community members. Many of those we spoke to remarked, for example, about a recent increase in polar bear sightings in the Kangerlussuaq region, attributed to the bears roaming south in search of food.

The Greenland expedition left a significant impression on the students. As the trip concluded, they reflected on their experiences and what the trip meant to them. Several reported that the experience sparked their interest in pursuing research about the environment or about climate science in graduate school. And after the expedition, the student participants remained engaged through analysis of the data collected during the trip and through advocating for climate justice and diversity in science, technology, engineering, and mathematics.

Involving undergraduate students in experiential learning introduces them to new skills and interests and is essential for academic and professional development. Research experiences in remote environments inspire students and allow them to explore a wide range of interests while learning how to create cohesive research plans and work through obstacles that arise in the field. This expedition enabled students to explore different fields related to polar science in a dynamic environment.

Leading a trip like this one is not an easy task. It requires extensive planning and organization, but it offers an important—and potentially career altering—learning experience for participants.

Author Information

Chelsea E. Snide ([email protected]), Lydia Gilbert, Abigail Meyer, Perry Samson, Mark Flanner, and Jeremy Bassis, University of Michigan, Ann Arbor

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

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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