Tag Archives: glacier

Juneau Jökulhlaup

Mendenhall Glacier

Since 2011, outburst floods from the glacial-dammed lake at Suicide Basin have been released into Mendenhall Lake and subsequently the Mendenhall River. The record setting flood of 2016 was at 11.99 feet. Flood stage is at 9′.

A home falls into the Mendenhall River after the bank gave way from the outburst flood.

That record was broken this weekend, when the flood waters burst from Suicide Basin. The water level crested at 14.97 feet. Several homes along the river had the bank cut out from under them, with at least one collapsing into the rushing current.

It was estimated that water was flowing at 20,900 cubic feet per second down the Mendenhall River.


New Glacier

A new glacier documented in the Shublik Mountains; Photo courtesy of Caltopo

A wilderness guide, Zachary Sheldon, came across a glacier in the Shublik Mountains in northern Alaska. Just thirty miles from the Arctic Coast and ten miles northeast of Alaska’s Brooks Range, it is the northernmost glacier in the United States.

Glaciers this far north are much different than glaciers on our southern coast. There isn’t much snow accumulating this far north, and the elevation of this glacier isn’t as high as others, as it sits at 4500 feet.

Like 99% of glaciers in Alaska, this newly discovered one is not growing in size.


Outburst

Public service announcement from the City of Valdez

An ice-dammed lake above the Valdez Glacier is undergoing an outburst event, which started on Friday. Water levels in Valdez Creek and Valdez Lake will be seeing a considerable rise.

This is a biannual event, which usually happens in mid June and then again in the fall. Water builds up in the lake above the glacier until the pressure raises the ice, and the water flows down the mountain.

The dammed lake

The image above shows the lake caught behind the ice dam. The ice wall in the picture is approximately 200 feet high.

First image credit: City of Valdez; Second image credit: National Weather Service


Kenai Fjords National Park

National Park Week, Day IV; Today’s Park Theme: Transformation Tuesday

Map of Kenai Fjords National Park

Kenai Fjords: Where Mountains, Ice and Ocean meet.

Kenai Fjords was first designated a National Monument in 1978. With the passage of ANILCA, the Alaska National Interest Lands Conservation Act in 1980, Kenai Fjords officially became a National Park.

Exit Glacier

Kenai Fjords encompasses 669,984 acres, which includes the massive Harding Icefield, which is the source of at least 38 glaciers.

Climbing up to Exit Glacier; Camera: Leica M3, Film: TMax100

Exit Glacier and the Harding Icefield can be reached from the community of Seward. It’s a short drive from town to the visitor center and trail head. The short and relatively easy trail takes one to the foot of the glacier. Exit is retreating at a pretty good clip, and is now losing ice during all seasons.

The Harding Icefield

The Harding Icefield covers over 700 square miles, and that does NOT include the 38-40 glaciers that spawn from it. The hike past Exit Glacier to the icefield can be described as strenuous, but the view, when clear, is absolutely amazing.

An emergency shelter surrounded by the Harding Icefield

Harding Icefield is one of four remaining in the United States, and the largest that is contained completely within the country. It receives, on average, 400 inches of snow each year.

Bear Glacier as seen from Resurrection Bay

Much of the Park is only accessible by water, and sea kayaking is a very popular activity. There are many tidewater glaciers that can be reached from Seward.

Kayakers dwarfed by Aialik Glacier

Two glaciers that I have visited from Seward are: Bear, which is the longest glacier in the Park, and Aialik Glacier, which is a bit more impressive from the water. Bear has receded to the point, that a lake now exists between the ocean and the glacier. The lake is often filled with small icebergs, which makes kayaking interesting. Aialik is a giant ice wall from the water’s surface.

Kenai Fjords National Park received 321,596 visitors in 2018. It is the fourth most visited Park in Alaska, and the closest to the city of Anchorage.

Find your Park!

Glacier on the move

Muldrow Glacier in Denali National Park is surging:

Muldrow Glacier, with Traleika Glacier coming in from the top left

In early March, pilot Chris Palm, who took the photo above, noticed something very different about Denali Park’s famed Muldrow Glacier. The normally smooth surface of the glacier was broken up by crevasses stretching across the width of Muldrow.

The long awaited surge had begun.

The 39 mile long, Muldrow Glacier last surged in 1957, so scientists were thrilled to study a natural phenomenon that has not occurred here in 64 years.

Surge-type glaciers are relatively rare, with approximately 1% of the glaciers world-wide being surge glaciers. Denali National Park has several, most of which get their start from the face of North America’s tallest peak.

Newly formed transverse crevasses on Muldrow

As snow and ice builds up at the higher elevations of a glacier, meltwater is also building up underneath the glacier. This meltwater acts as a lubricant when the weight from above passes equilibrium. The glacier then surges downward at a rate of up to 100 times faster than normal. At some point, the meltwater trapped under the glacier will be released in an outburst flood. Once the water is reduced significantly, the glacier’s surge will slow and it will go back to a state of quiescent (non-surge) once again. Over time, the process repeats itself. Muldrow Glacier has a history of surging roughly every 50 years.

An animated time-lapse of Muldrow Glacier on the northeast flank of Denali. The starting time is August 2018.

There are two GPS stations on the glacier to monitor its movement. There are also four time-lapse cameras facing different areas of the glacier, including one at the terminus to monitor the glacier’s “bulldozing action”. Another is looking over the McKinley River in order to capture images of the outburst flood. The Alaska Earthquake Center also has a seismic monitoring station, and a sound station has also been installed in an attempt to capture the grinding sound of the surging glacier.

Mapping Muldrow’s movement

In 1957, most accounts have the surge starting in May, 1956 on Traleika Glacier, which is the main tributary of Muldrow. Muldrow Glacier would advance over 4 miles before the surge ended in September of 1957. Approximately 3.3 cubic kilometers of ice was redistributed from the upper reaches of the glacier to its toe. At the upper levels, the ice thickness had dropped as much as 170 meters, but the toe rose to a 200 foot tall ice wall.

Currently, the Muldrow Glacier is moving between 10 to 20 meters per day, and is only 800 meters short of the 1957 terminus. At the current rate of surge, Muldrow will reach the 1957 distance in June.

All images, photos and maps are courtesy of the NPS; Sources include: NPS – Denali NP&P, Alaska Department of Natural Resources, University of Alaska – Fairbanks


Glacier Scouring

Film Friday:

Worthington Glacier Valley

Camera: Minolta SRT201


Bear Glacier

Bear Glacier of Resurrection Bay


Operation Ice Bridge

Operation Ice Bridge is a NASA mission to monitor the changes in polar ice. The program was started in 2003. Here are some photos that NASA took during their time over Alaska.


Pools of meltwater atop Columbia Glacier; Prince William Sound, Alaska


Miles Glacier, near Cordova, Alaska. Cordova’s “Million Dollar Bridge”, was officially known as “The Miles Glacier Bridge”. The glacier terminates at Miles Lake, which has formed in the past 100 years.


Icy Bay in the Wrangell-St Elias Wilderness, Alaska. A century ago, the body of water was covered in glacial ice.


A refurbished DC-3 takes off from Kulusuk, Greenland on a survey of Eastern Greenland. I just think it’s incredibly cool that they are flying a DC-3.

All Photos credit: NASA, DC-3 photo credit: NASA/JPL-CalTech


Exit Glacier: Video

I visited Exit Glacier this past summer, and did a post on it at that time. This is short video of that glacier. It has some beautiful footage of the Seward area. The glacier was receding by 150 feet a year; it is now losing 10-15 feet a day.

Film credit: Raphael Rogers, Paul Rennick. Film editor: Kristin Gerhart


Exit Glacier

While in Seward, we made a trip out to Exit Glacier, which is in Kenai Fjords National Park. Exit, is one of over 30 glaciers that flow out from the Harding Icefield. Although, Exit Glacier is by far the most accessible. It’s a 4.1 mile hike from the visitor center to the edge of the Harding Icefield.


Harding Icefield, which is several thousand feet thick.

Kenai Fjords is a trip back in time. A series of signs show where the glacier was from 1815 onward. As one gets closer to the glacier, the woods become younger and younger.


Exit Glacier terminus map. Credit: NPS.Erin Erkun

The glacier was originally known as Resurrection Glacier, as the glacier’s melt flows into the Resurrection River and finally Resurrection Bay. The first documented trip across the Harding Icefield in 1968, saw the team “exit” the ice field from Resurrection Glacier, and the nickname “Exit” Glacier stuck.


Photo credit: ADN

Exit Glacier is retreating in winter now, as well as summer, and it has been since 2006. The sign post showing where the terminus was in 1917, is now approximately a mile from the current terminus. The summer of 2016 set a record for the glacier: Exit retreated 252 feet, the most of any summer since records have been kept. For that year, the glacier saw 293 feet disappear.


Map credit: ADN