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29 July 2022

A high-country Eden for sockeye salmon

In late summer, a few months before this mossy valley will feel the sting of 40-below air, bright red salmon dart through a crystal-clear pool amid fragrant green vegetation. The Gulkana Hatchery has a Garden-of-Eden feel, which is fitting since millions of sockeye salmon begin life here each year.

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7 July 2022

A half century in a difficult, dynamic place

Dan Mann hands me a clump of orange dirt the size of an almond. He instructs me to put it in my mouth.
“What’s it taste like? Does it crunch? Ash crunches because there’s glass fragments in it.”
“It crunches.”
“It’s from Mount Edgecumbe,” he says, referring to a volcano 100 miles away, near Sitka. “From an eruption 13,000 years ago.”

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5 July 2022

Salmon nose deep into Alaska ecosystems

A salmon head at its final resting place on the upper Chena River, one of the most important birth streams for Chinook salmon. Photo by Ned Rozell. That’s the finding of scientists who study Alaska streams and rivers that are teeming with salmon.

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29 June 2022

Bonsai trees tell of winters long past

“These are museum-class bonsais,” Ben Gaglioti says as we walk through an elfin forest. Gaglioti, a University of Alaska Fairbanks ecologist, has led me into another landscape I have never seen in Alaska. This terrace of spongy ground above the rainforest is home to trees that Dr. Seuss might have dreamed up.

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22 April 2022

His 48th summer on top of the world

This June, George Divoky will refurbish a cabin that sits on a lonely gravel island north of Alaska. He was not planning a remodel this year. Sometime during the winter, a polar bear tore through a plywood wall of the cabin Divoky moved 20 years ago to Cooper Island.

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18 April 2022

Tracking ocean expeditions while at sea with Google Earth

For those that head off to do fieldwork, especially on the ocean, I encourage you to think about creating your own Google Earth file with daily updates to keep other engaged and informed about your work.

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31 March 2022

Happenings north of the Arctic Circle

Though the calendar calls it springtime, the thermometer on the truck reads minus 28 F on this sunny morning a few days past spring equinox. I am riding shotgun with Knut Kielland, an ecologist at the Institute of Arctic Biology at the University of Alaska Fairbanks. He has invited me to join him for a week north of the Arctic Circle — 66.6 degrees north latitude, about 150 miles from Fairbanks.

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4 November 2021

Shorebirds depend on wee slivers of Alaska

Pencil-beaked shorebirds with the ability to stay airborne for a week — flying all the way from Alaska to New Zealand — rely on a few crescents of mudflat to fuel that incredible journey.

Scientists recently found that almost the entire population of bar-tailed godwits that breed in Alaska fatten up on clams and worms on ephemeral sand bars just west of the mouth of the Kuskokwim River. In autumn, 80 percent of the birds rest and feed on islands within 15 miles of one another.

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1 October 2021

Fluorescent bill may be seabird’s neon sign

The crested auklet looks like a smiling clown that never blinks. It is probably the only seabird that smells like a tangerine. Its beak — the color of a tangerine — is so bright a scientist thinks it may be fluorescent.

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12 August 2021

Pine grove near Yakutat is farthest north

We were on the Yakutat Forelands — a sweep of forested lowlands left behind after glaciers retreated from the landscape hundreds of years ago. Taking steps that felt like walking on a trampoline, we moved through a pine grove in a few-acre spread of open green muskeg.

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15 July 2021

Visit to glacier begins with wildlife encounter

We heard a loud buzz. A hummingbird hovered in front of my cracker. As I held still, the hummingbird probed the peanut butter, twice, with its needle beak. The cracker transferred the vibration to my left hand, tickling my fingers. As the bird zoomed off, I looked over at Ben to confirm the experience.
“I think you have superpowers now,” he said.

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22 June 2021

Low-displacement landslides explain unusual West Virginia landscape features visible in lidar imagery

Like so many older landslides in the Appalachians, the significance and cause of these features is unknown. Because they are so numerous and are only visible using lidar data acquired in 2016, they may represent an untapped resource of useful information about the recent history of Appalachian landscapes.

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16 April 2021

Listening to avalanches half a state away

High on the broken pyramid of Iliamna Volcano, rotten rock held in place by volcano-warmed ice sometimes loses its grip. Several times over the years, rock-and-ice avalanches have blasted down Iliamna at 150 miles per hour. Left behind on the mountain’s face is a dirty, five-mile scar, in the same place as the last one.

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24 March 2021

What does that landslide actually look like, part 2: an active landslide

As indicated in the previous post, lidar-derived imagery still needs ground-truthing to maximize its usefulness as a means of characterizing landslides and other slope failures. Last June, Ken Gillon and I visited the Rutherford County, North Carolina, landslide described below as part of our work with Appalachian Landslide Consultants, PLLC (ALC) on behalf of the North Carolina Geological Survey. This slide caught my eye in lidar hillshade imagery because it appeared to share characteristics with an active slide we had visited a few days before.

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1 March 2021

What does that landslide actually look like?

We have no constraints on the age of the slides, but they may reflect logging history in the area. The majority of these slopes were heavily and continuously logged during the past ~150 years, with logging in this area clearly occurring within the past 50 years. The slides may have developed after clear-cuts, with the rapid return of vegetation common in the region quickly making the area look less disturbed than it really is.

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Malaspina Glacier gets up and goes

Massive icefields near the Canada/Alaska border feed Malaspina ice through a slot in the mountains. Freed of mountain walls, Malaspina’s ice oozes over the coastal plain like batter on a hot griddle. Near the Gulf of Alaska about 30 miles northwest of Yakutat, the glacier is — on clear days — visible from a window seat on an Alaska Airlines flight from Southeast Alaska to Anchorage. But the dirty-white blob on the cheek of Alaska is not as large as it used to be, which is why glaciologist Martin Truffer and his colleagues are studying it.

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24 February 2021

Lidar-derived imagery of 1949 debris flows on North Fork Mountain, Grant County, West Virginia

Debris flow events present a significant hazard to life and property in all parts of the Appalachians. The 1949 event that created the features shown here caused 8 fatalities and displaced a tremendous number of residents. Detailed mapping…along with analysis of detailed surface imagery, can greatly enhance understanding of where debris flows begin and where they travel. This understanding, in turn, can potentially reduce the human impact of these particularly dynamic and mobile slope failure events.

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11 January 2021

Giant storms, big waves and chilly winds

…the Howard Pass weather station in the western Brooks Range recorded an air temperature of minus 33 degrees Fahrenheit. At the same time, the wind was blowing 47 miles per hour. That’s a windchill of minus 78 degrees. That inhumane condition is not unusual for Howard Pass, a relative low spot (2,062 feet) in Alaska’s farthest-north mountain range.

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2 October 2020

Fall equinox and the big turn

On the first day of October, a little girl pulls on her rubber boots and rushes outside into crisp fall air. She knows the days are getting shorter, but she doesn’t realize Alaska is a week past the autumnal equinox. On the equinox, the sun appears to sit over Earth’s equator, causing days and nights to each last about 12 hours everywhere in the world. It is time for Alaskans to start paying the bill for all that summer daylight.

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19 September 2020

Postcards from a formerly frozen icebreaker: Part 60 — Last Ice

We are now in open water and have left the ice behind. In the last hours we cruised through the last remnants of ice. Little chunks floating alone, their hours numbered out here in the water that is now creeping slightly above the melting point.

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