Tag Archives: map

Look up!

A magnetic storm is headed our way from the sun, which should offer great aurora viewing Sunday and Monday. Hopefully the clear skies hang around tonight. With a forecast of -20F, I am assuming we will have the all clear for the aurora.

Graphic credit: UAF Geophysical Institute


Reverb in the Nenana Basin

Graphic credit: UAF Geophysical Institue

The Nenana Basin lies southwest of Fairbanks. The Parks Highway runs along its eastern boundary, and the Tanana River runs right through the middle of it. The basin is 56 miles long and 7.5 miles wide. Over the course of millions of years, the basin has been filled in with river sediment. Considering that the basin is 4 miles deep (7km), that is a lot of fill.

Several entities have been drilling test holes throughout the basin looking for oil and gas, so the University of Alaska – Fairbanks has been studying the basin’s makeup. One thing they found is that earthquakes last longer and feel a lot stronger in the basin, than just outside the basin.

The shockwaves from an earthquake travel differently through the sediment, which is mostly gravel, than the solid rock along the ridge lines. Reverberation also plays a roll here: The seismic waves are amplified by the basin walls and floor.

Seismic sensors have verified what local residents have been claiming: The shaking is a lot worse down in The Flats than up in the hills.

Source credit: Alaska Public Media, University of Alaska – Fairbanks


Alaska helped take down the Roman Republic

Volcano Week:

Okmok Volcano; Image credit AVO

Ice core records from the Arctic show that Alaska’s Okmok Volcano had a massive eruption in 43 BCE. Following the eruption, there was an abrupt cooling globally, which led to crop failures, famine, disease, and eventually, social unrest. The Mediterranean region was no exception to this.

Such a shift in climate, coming a year after the assassination of Caesar, would have put great pressure on local powers. Strain was also felt in Egypt.

Okmok has a very active history. At one time, it had a 150 meter deep lake in its crater. A notch in the rim eventually drained the lake, although some small remnant lakes remain near cones B & D.

The eruptions of Okmok 8300 and 2050 years ago earn a Volcanic Explosivity Index rating of 6, which puts it on par with Novarupta and Krakatoa.

On 12 July 2008, Okmok erupted without warning, sending ash 50,000 feet into the air. It erupted continuously for almost six full days, causing transportation problems in the air and on the water for the region. That eruption was ranked a 4 VEI, which is considered “cataclysmic”.

Okmok Volcano; Photo credit: AVO/Burke Mees

Back to 43 BCE. The decade following the eruption was one of the coldest in a millennia, with 43 and 42 BCE being some of the coldest years. It is believed that a temperature drop of 7C from normal was a result of the volcanic eruption on the other side of the globe.

The full, scientific report can be found here:

https://www.pnas.org/doi/full/10.1073/pnas.2002722117


The Islands of the Four Mountains

Volcano Week:

An Aleutian Caldera?

There is a cluster of volcanic islands in the Aleutian Chain that scientists have recently been asking a rather provocative question: Could they all be a part of one giant super volcano, similar to the Yellowstone Caldera?

This tight grouping of islands is home to six stratovolcanoes: Carlisle, Cleveland, Herbert, Kagamil, Tana and Uliaga. Mount Cleveland has been one of the most active volcanoes in North America over the past 20 years.

Most stratovolcanoes tend to have modest sized reservoirs of magma. Although that doesn’t mean they can’t have explosive eruptions, but they are dwarfed by caldera forming eruptions. A caldera is formed by tapping a huge reservoir of magma in the earth’s crust. A caldera forming eruption releases a massive amount of lava and ash, and they are catastrophic, often causing world-wide effects.*

Field work continues, although there is nothing easy about doing research in the Aleutians.

Mount Cleveland

Photo and map credit: USGS, *University of Alaska – Fairbanks


The Chilkoot gets historic status

The Golden Staircase on the Chilkoot Trail

The Federal Government has designated the Chilkoot as a national historic trail. Gaining fame during the Klondike Goldrush, the Chilkoot was a major thoroughfare into the interior of the Yukon and Alaska. Prior to that, the trail was a major route for the Native population for a millennia.

The Chilkoot: Alaska to Canada

Currently, the Chilkoot is closed due to major trail damage from flooding this past autumn. A series of atmospheric rivers pummeled the area, The Taiya River reached flood stage on five different occasions during a two month period last fall, eroding banks and dislodging bridges along a large section of the trail, that follows the river.

There is hope that the trail will be open at some point this summer. The complete trail to Bennett Lake has not been open due to Canadian restrictions since the start of the Corvid pandemic. There is also hope that those restrictions will also be lifted for the upcoming hiking season.

Hiking the Chilkoot

The Iditarod 2023

The “other” sled dog race in Alaska is the Iditarod. Like the Yukon Quest, mushers have been slow to sign up to run in 2023. As of last week, 34 mushers had committed to race. Only one year had such a low number, and that was the first year in 1973.

Several factors have entered into the low number, but the price tag to train a team of dogs right now seems to be the driving factor. The price of gasoline, dog food, and even straw has gone up considerably this past year. A team of 45 dogs can go through six pallets of dog food a year. The average price of a pallet of food has increased by $700 in Alaska, if you train on the road system.

Legends of the sport are also seeing their careers wind down. Jeff King, Dallas Seavey, Mitch Seavey, Joar Leifseth Ulsom and Martin Buser have won a total of 17 races among them, yet none of them have signed up to run in 2023.

The past ten years have seen an average of 64 mushers at the starting line, and 2016 had 85 mushers in the field.

The Iditarod Trail Map

The race to Nome will follow the southern route through the abandoned mining town, and race namesake, Iditarod. Then through Anvike and north to Kaltag, where it rejoins the main trail to Nome.

The ceremonial start in Anchorage is set for March 4, with the restart in Willow the following day.


Bright Lights

NOAA’s Aurora Forecast

Weather permitting, we are looking at some phenomenal aurora viewing over the next few nights. Halloween weekend also looks to be quite good for viewing.

Image credit: UAF’s Geophysical Institute


Russians make escape to Alaska

St Lawrence Island; Photo credit: KNOM/Laura Kraegel

Lost in the excitement and drama of Fat Bear Week, was the story of how two Russian nationals crossed the Bering Sea in a boat, landed on St Lawrence Island, and turned themselves in to authorities in Gambell, Alaska. The two men were seeking asylum in order to escape Putin’s War in Ukraine.

Gambell, Alaska, population 600, is actually much closer to the coast of Russia, than it is to Nome, which is 200 miles away. The two Russian men were flown to Anchorage.

The incident adds to the drama going on between Alaska and Russia. Russian military aircraft have been veering into Alaska airspace for several years now, and recently, the USCG followed a flotilla of Chinese and Russian naval ships out of the Aleutian Islands.


The remnants of Merbok…

…still packed quite the punch.

Graphic credit: NWS-Fairbanks

The western coast of Alaska was pummeled over the weekend by the remnants of Typhoon Merbok. Sustained winds over 50 mph, with gusts over 90; 50 foot waves and a storm surge 15 feet above high tide left many evacuating to higher ground.

Image credit: NOAA

It was the worst storm our Western Coast has experienced in 50 years, and it has been 70 years since a storm this fierce hit in September.

Front Street, Nome, Alaska; Image credit: S.Kinneen

To its credit, The National Weather Service was remarkably accurate in its forecast of the storm. Several days out, the NWS was getting out the word that this was going to be a devastating flooding event. All the ingredients came together perfectly to create some “very angry seas”.

A house swept off its foundation by flood waters, stuck at the Snake River Bridge in Nome, Alaska; Photo credit: Alaska DOT&PF
From the steps of the school in Golovin, Alaska; Photo credit: Josephine Daniels

High winds have taken roofs off of buildings, one building in Nome suffered from a fire, and the storm surge has evicted hundreds. Many took shelter in schools, or to higher ground.

My favorite village of Newtok has been flooded, and many have taken to the school for shelter. The riverbank at Newtok has eroded between 10-15 feet overnight. Newtok is one of several villages in Alaska in dire need of relocation due to erosion and sinking ground.

Water levels in many flooded villages are not expected to drop until Monday, and in some cases Tuesday. The timing of the storm is particularly difficult, with winter on the horizon. The village of Shaktoolik lost its sea berm to the storm, which leaves it vulnerable to additional winter storms. The village of Chevak lost much of its fishing fleet when boats sank or were damaged in the storm.

We really have two seasons in Alaska: Winter, and Preparing for Winter. Preparing for winter in Western Alaska is now going to be a huge challenge.


Summer ’22 Wrap-up

Data credit: ACCAP; Graphic credit: @AlaskaWx

The Lower 48 remains caught up in the heat of summer, but autumn has taken hold in Alaska. The seasonal graphic that AlaskaWx puts together is a review that I always enjoy, so I’m sharing it here.

Weather-wise, Alaska was all over the map this past summer. Fairbanks had one of our driest summers on record, while Anchorage had a top three driest June, only to then see a top three wettest August.

Toolik Lake had snow in July, while Denali Park saw the white stuff accumulate in August.

The Southeast had an early heatwave, and Cold Bay saw a record early first freeze.

Overall, Alaska has seen 3.11 million acres burn to wildfire, which is the seventh largest burn season since 1950.