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New study raises concerns as major icefield in Alaska melts at alarming rate

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New study raises concerns as major icefield in Alaska melts at alarming rate


JUNEAU, Alaska (KTUU/Gray News) – A new study highlighted the shrinking Juneau Icefield in southeast Alaska as an example of how Earth’s glaciers are nearing an “irreversible” tipping point for melting.

“If there are processes in Alaska that are accelerating the melt, they may be relevant to other parts of the world as well,” said Bethan Davies, the paper’s lead author, about the global significance of studying Alaska’s glaciers.

The Juneau Icefield is home to dozens of large glaciers — including the popular Mendenhall Glacier in Juneau — and many more smaller ones. By 2100, many of these glaciers are at risk of disappearing. Experts say if the Earth continues to warm, nearly 70% of the world’s roughly 200,000 glaciers will dry up by the end of the century.

The approximately 1,500-square-mile Juneau Icefield blankets the mountains north of Juneau.(U.S. Geological Service)

“When we look at the last 10 years worth of glacier change over all of Alaska, we are seeing a real uptick [in melting] that’s faster than in some other parts of the world,” said Davies, who is also the glaciologist and senior lecturer in Physical Geography at Newcastle University. “And it’s very interesting to ask why that’s happening and why these glaciers are not only accelerating but also how they might behave in the future.”

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The study, published this month in the journal Nature Communications, showed from the years 1770 to 1979, ice volume loss remained fairly consistent, at roughly 1 kilometer cubed per year.

From 1979 to 2010, there was slightly more melting, but the loss at 3.1 kilometers cubed per year remained fairly consistent.

However, from 2010 through 2020, the Juneau Icefield’s melting rate doubled to almost 6 kilometers cubed per year. That’s the equivalent of 2.4 million Olympic-size swimming pools melting off of the icefield each year.

The Mendenhall Glacier is one of the dozens of major glaciers that extend out from the Juneau...
The Mendenhall Glacier is one of the dozens of major glaciers that extend out from the Juneau Icefield.(Alaska’s News Source)

That icefield thinning led to the formation of Suicide Basin, which saw its first glacial lake outburst in 2011.

“This can only happen because that whole glacier system, as was pointed out in the study, is thinning,” Alaska climate specialist Rick Thoman said. “It’s thinning a lot and it’s thinning rapidly.”

This water release will happen every year, with some years seeing the potential for historic flooding. But as the glacier keeps thinning, Suicide Basin will reach a point where a glacial lake outburst will no longer form.

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However, Thoman says newer basins can form.

“It’s entirely possible given the complex nature of the Juneau Icefield, we might see a new glacier dammed lake form in some other part of the system,” Thoman said. “But as last year showed, when there’s a lot of water in these glacier-dammed lakes, and when they release all the water, we get the devastation that we saw last August.”

All of that melting eventually gets dumped into the ocean. According to Davies, glacier melt accounts for about a quarter of the total sea level rise. The remainder comes from the Antarctic ice, Greenland ice sheet and thermal expansion of the ocean.

“A part of the world that’s contributing the most to sea level rise is Alaska,” Davies said. “The Alaskan glaciers are really important in the global context because there’s a large volume of ice.”

She said this study isn’t relevant to just Alaska, because the same processes occurring here in Alaska may be relevant to other parts of the world.

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“What’s happening is that the temperature is gradually increasing,” Davies said. “But as that happens, there’s a series of processes that are accelerating melt or amplifying melt.”

One of those processes is the snow line, which continues to dwindle during the summer months.

Davies said the end of summer snow line is actually reaching the top of the low slope, plateau area. This is historically lower than in previous decades when snow was covering the plateau all year round.

Another challenge is that as more of the plateau is exposed, it’s darkening the mountain as more rocks are exposed from the melting ice.

“When we remove the snow, we are reflecting less of the sun’s energy back into space,” Davies said. “Because snow is very bright and white and reflective. So what we’re doing when we raise that end of summer snow line is we expose much more of the glacier to that darker color so it can absorb more of the sun’s energy.”

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Thoman said with the summer snow line dwindling, the atmosphere’s snow level rises with atmospheric rivers aiding in transporting warmer air.

“To hold as much water in the air as those atmospheric rivers bring, the air has to be warm,” Thoman said. “If it was colder it wouldn’t be able to hold as much moisture.”

Thoman said it’s both the high precipitation events and warm airmass that are helping to drive snow levels very high into the atmosphere, which can and do occur all winter long, some years.

Climatologically speaking, Juneau temperatures have warmed a few degrees over the last several decades. And while that may not seem like much, when temperatures are hovering around freezing, that can still have large impacts.

“We’re right around that freezing level,” Thoman said. “So an increase of 31 to 33 [degrees], say, as an average temperature is much more significant when you’re talking about snow and ice than say an increase of 40 to 43.”

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Davies doesn’t think the Earth’s ice has passed the point of irreversible change but does argue that such a threshold could occur by the end of this century.

And if the feedback loop of melting continues, the icefield will eventually reach a point where it will be difficult to recover from.



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Alaska

Alaska senator highlights truck drivers hauling Capitol Christmas Tree to D.C.

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Alaska senator highlights truck drivers hauling Capitol Christmas Tree to D.C.


ANCHORAGE, Alaska (KTUU) – Alaska Sen. Dan Sullivan welcomed Americans to enjoy the massive Sitka spruce that is currently making its way to the nation’s capitol by truck and praised the two drivers hauling the 85-foot tall tree.

In his weekly “Alaskan of the Week” address on the floor of the U.S. Senate on Thursday, Sullivan spent about 15 minutes explaining how the Capitol Christmas Tree — taken from the Tongass National Forest near the Southeast Alaska community of Wrangell — was selected and how it’s being transported nearly 5,000 miles to be put on display in Washington D.C.

The duo of Fred Austin of North Pole and John Shank of Fairbanks have been part of that journey. Austin is 89 years old and has driven commercially for 71 years, while Shank is about to hit 50 years driving for Lynden Transport.

Together, the duo have logged over 10 million miles of driving trucks in their career.

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Sullivan said the two will have driven through 12 states and 17 towns across the country before making it to D.C. on Friday.

See a spelling or grammar error? Report it to web@ktuu.com



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OPINION: VPSO growth strengthens Alaska public safety

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OPINION: VPSO growth strengthens Alaska public safety


By James Hoelscher

Updated: 34 seconds ago Published: 19 minutes ago

Under Gov. Mike Dunleavy’s leadership and with reliable funding from the Alaska Legislature, Alaska’s Village Public Safety Officer (VPSO) program has experienced substantial growth, reflecting Alaska’s commitment to public safety across its communities. The number of VPSOs working in our remote communities was once at 42 officers in January 2020 and has grown to a current total of 79, along with the introduction of Regional Public Safety Officers (RPSOs) and competitive wage adjustments, the VPSO program has become more robust and better equipped to serve the needs of rural Alaska.

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This increase in officer numbers is a significant accomplishment, expanding the safety network across Alaska’s rural communities. Each new VPSO represents not only an additional first responder but also a vital resource for residents in need of emergency response, search and rescue, and community safety support. By nearly doubling the number of officers in just a few years, the program has strengthened statewide readiness and improved the capacity to address Alaska’s unique rural challenges.

A key initiative supporting this growth has been the addition of Regional Public Safety Officers (RPSOs). RPSOs enhance the effectiveness of local VPSOs by providing a layer of specialized regional support, acting as a resource that multiple communities can rely on in times of need. They can respond quickly with the Alaska State Troopers to large-scale incidents, provide backup to VPSOs during demanding situations, and share essential resources across multiple villages. This novel regional approach ensures that communities have comprehensive public safety coverage including their local VPSO, regional RPSO, and the Alaska State Troopers.

Another major factor in the VPSO program’s expansion has been the increase in wages, making the role more competitive and sustainable as a career. Recognizing the high costs of living and the challenges of public safety work in rural Alaska, recent adjustments to VPSO compensation have made these positions more appealing to qualified candidates and have strengthened officer retention. This increase underscores the commitment required of VPSOs, who serve as the primary responders for some of Alaska’s most isolated communities. By offering competitive pay, the program attracts skilled individuals committed to public safety, building a more dedicated workforce equipped to serve Alaska’s rural residents.

These improvements in staffing, regional support through RPSOs, and wage enhancements have created a VPSO program that is more resilient and adaptable than ever before. VPSOs provide critical services to safeguard the well-being of residents, and the increased investment in personnel and resources underscores Alaska’s dedication to supporting its rural communities.

Looking ahead, the VPSO program will continue to focus on these priorities to ensure that Alaska’s rural communities have the support they need. We remain committed to working closely with Dunleavy, the Legislature, the regional VPSO grantees and Alaska’s villages to ensure that every village that wants a VPSO can have a VPSO.

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James Hoelscher is currently the director of the Alaska Department of Public Safety’s Village Public Safety Officer Operations Division. He previously worked as the chief of police in the Village of Hooper Bay, as a Village Public Safety Officer in Hooper Bay, and for the Alaska Alcohol and Marijuana Control Office.

The views expressed here are the writer’s and are not necessarily endorsed by the Anchorage Daily News, which welcomes a broad range of viewpoints. To submit a piece for consideration, email commentary(at)adn.com. Send submissions shorter than 200 words to letters@adn.com or click here to submit via any web browser. Read our full guidelines for letters and commentaries here.





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Among butter clams, which pose toxin dangers to Alaska harvesters, size matters, study indicates • Alaska Beacon

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Among butter clams, which pose toxin dangers to Alaska harvesters, size matters, study indicates • Alaska Beacon


Butter clams, important to many Alaskans’ diets, are notorious for being sources of the toxin that causes sometimes-deadly paralytic shellfish poisoning.

Now a new study is providing information that might help people harvest the clams more safely and monitor the toxin levels more effectively.

The study, led by University of Alaska Southeast researchers, found that the meat in larger butter clams have higher concentrations of the algal toxin that causes PSP, than does the meat in smaller clams.

“If you take 5 grams of tissue from a small clam and then 5 grams of tissue from a larger clam, our study suggested that (in) that larger clam, those 5 grams would actually have more toxins — significantly more toxins — than the 5 grams from that smaller clam,” said lead author John Harley, a research assistant professor at UAS’ Alaska Coastal Rainforest Center.

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Partners in the study were the Sitka Tribe of Alaska, which operates one of only two laboratories in the state that test shellfish for algal toxins, and with other organizations.

It is one of the few studies to examine how toxin levels differ between individual clams, Harley said.

The findings came from tests of clams collected from beaches near Juneau on five specific days between mid-June and mid-August of 2022.

The 70 clams collected, which were of varying sizes, yielded a median level of saxitoxins of 83 micrograms per gram, just above the 80-microgram limit. Toxin concentrations differed from clam to clam, ranging from so low that they were at about the threshold for detection to close to 1,100 micrograms per gram.

And there was a decided pattern: Toxin concentrations “were significantly positively correlated with butter clam size,” the study said.

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A woman sorts though a pile of butter clams on a dock in Alaska in 1965. Butter clams have long been harvested for personal consumption in Alaska. (Photo provided by the Alaska Department of Fish and Game)

Among the tested clams in the top 25% size, 81% had concentrations above the regulatory threshold, while among the quartile with the smallest size, only 19% came in at above the threshold.

The typical butter clam has a shell that is about 3 inches wide and up to 5 inches in length; clams in the study ranged in shell width from less than 1.5 inches to more than 4 inches. The mass of meat inside the shells of tested clams ranged from 3.87 grams to 110 grams, the study said.

The detections of toxins were in spite of the lack of significant algal blooms in the summer of 2022 – making that year an anomaly in recent years.

In sharp contrast, the summer of 2019 — a record-warm summer for Alaska — was marked by several severe harmful algal blooms. Near Juneau, toxin concentrations in blue mussels, another commonly consumed shellfish, were documented at over 11,000 micrograms per gram, and the toxins killed numerous fish-eating Arctic terns in a nesting colony in the area.

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Just why the butter clams tested for the new study showed concentrations of toxins in a low-bloom year is a question for further review.

Butter clams are known to pose special risks because they retain their algal toxins much longer than do other toxin-affected shellfish. Like other species, butter clams do detoxify over time, but they do so much more slowly, Harley said. The clams in the study were all at least a few years old, and there are some possible explanations for why they still retained toxins in the summer of 2022, he said.

“Maybe these larger clams, because they’ve been consistently exposed to harmful algal blooms several years in a row, maybe they just haven’t had a chance to detoxify particularly well,” he said.

The unusual conditions in the summer of 2022 mean that the results of this study may not be the same as those that would happen in a summer with a more normal level of harmful algal blooms, he said. “It still remains to be seen if this relationship between size and toxin is consistent over different time periods and different sample sites and different bloom conditions,” he said.

Research is continuing, currently with clams collected in 2023, he said. That was a more typical year, with several summer algal blooms. 

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The algal toxin risks in Alaska are so widespread that experts have coined a slogan that reminds harvesters to send samples off for laboratory testing before eating freshly dug clams and similar shellfish: “Harvest and Hold.”

Harley said the fact that there are toxins in clams even when an active bloom is not present “is a very real concern” for those who have depended on harvest. The Southeast Alaska Tribal Ocean Research Network, known as SEATOR, has been monitoring shellfish in winter and other times beyond the usual months of algal blooms, he noted.

That monitoring has turned up cases of toxin-bearing shellfish well outside of the normal summer seasons. Just Tuesday, SEATOR issued an advisory about butter clams at Hydaburg, collected on Saturday, that tested above the regulatory limit for safe consumption.

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