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The permafrost risk

Logo https://permarisk.pageflow.io/the-permafrost-risk

Risko Permafrost

The train ride from Winnipeg in southern Canada to Churchill in the North takes three days - through 1.000 kilometers of wilderness. The climate gets colder and colder towards the North. About midway, the train starts to ride over frozen ground. Here starts the permafrost, soil that is frozen all year round.


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Every year the uppermost layer of the permafrost thaws in spring and refreezes in autumn. This recurring thawing and freezing causes the soil to move. And this movement deforms the railway tracks. The train therefore drives only very slowly across the permafrost terrain and the conductor has to stop often to check the tracks.
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A broken lifeline

View of Churchill during winter.
View of Churchill during winter.
Vollbild
In 2017 a spring flood eroded the railway at several places. The train was out of service for 18 months. Goods and people could only be transported to Churchill by plane. The costs for food, gas and other goods skyrocketed. Tourism dropped and with it the revenues of businesses. Staff had to be laid off.

“Losing the rail here in Churchill was difficult on everybody. Right off the bat the prices of everything just absolutely rose astronomically in the stores. My wages didn't go up or anything like that. Prices for mail went through the roof, too, because everything had to be flown in now. People left. Families just didn't want to deal with this anymore and left our community. Long term families moved on to greener pastures somewhere else. It was really, really hard.” [Kevin Burke, local guide]

The railway is also an important trade route. Churchill is located at the Hudson Bay and holds a deepwater port. Grain from southern Canada is transported by train to Churchill and exported from there over the Arctic Ocean.
View of Churchill during winter.
View of Churchill during winter.
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Flooding is not the only event that can destroy the railway. Thawing permafrost also poses a big threat. When permafrost thaws, the soil softens, gives in or starts to slide. With climate change permafrost thaws deeper and longer during summer - a risk for any infrastructure like buildings, streets or railway tracks to be damaged.
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Moritz Langer, Ph.D., leads a team of scientists at the Alfred Wegener Institute for Polar and Marine Research in Germany. The PermaRisk team investigates how permafrost is changing in the Arctic. The scientists rebuild the Arctic landscapes and its processes in a computer simulation using physical equations. The result is the PermaRisk model CryoGrid. The scientists use CryoGrid to estimate what happens with the permafrost in the future. And they calculate the risks that thawing permafrost poses for Churchill’s infrastructure like the railway.
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Moritz Langer, Ph.D.

 Research director of PermaRisk

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The permafrost landscape along the railway resembles a colorful mosaic. Small and large lakes alternate with wet tundra meadows and small groups of trees. Wet terrain with lush green moss appears next to dry patches of white lichen. Small rivulets cut through the landscape and there are frost cracks to be seen that form polygonal patterns.
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Permafrost lies hidden below each of the pieces of the mosaic - changing properties along the way. Smallest differences in terrain height like cracks, hollows and bumps change the moisture and vegetation and therefore the temperature of the soil. Under wet mossy tundra meadows the permafrost is wet and cool. Here, the frozen soil contains a lot of ice and a lot of heat is required in the spring to thaw the soil. Drier areas on the other hand thaw faster and deeper. Scientists need to take a lot of measurements across this mosaic to get an accurate understanding of the permafrost landscape as a whole.
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Click on the circles on the next page and discover what the scientists of the PermaRisk team are measuring in the permafrost landscapes!
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Measuring thaw depth

A soil probe measures the thaw depth in summer. The scientists hammer the rod into the soil until it strikes the hard, frozen ground - the permafrost table. The PermaRisk model CryoGrid can calculate the thaw depths across permafrost landscapes. The scientists compare the actual measurements with the calculations to test the model performance.

Permafrost from the air

A drone flies over the tundra and takes high-resolution aerial images. Click here to find out what scientists can learn from those images!

Beneath the surface

The scientists take soil samples to learn more about the permafrost. Click here to find out more!

Measuring lake depth

The PermaRisk scientists want to know the depth of the lakes in the Arctic. Click here to find out why!

Measuring weather and climate

A climate station records the local weather. It measures air temperature, wind, precipitation (rain and snow), humidity and solar radiation. These variables describe the day-to-day condition of the atmosphere - the weather. Scientists only talk about climate and climate change when averaging the weather conditions over a period of 30 years and more. The PermaRisk team needs both weather and climate data to accurately calculate the temperatures in the permafrost over time.

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Thomas Schneider von Deimling is one of the modelers in the PermaRisk team. Up until now the CryoGrid model could not calculate how permafrost would thaw under a road. Thomas has now identified all important processes and feedbacks that describe the heat exchange between the permafrost and the road. He then built these processes as physical equations into the model. Now Thomas can calculate different future scenarios for the road: How fast will permafrost warm below the highway under a changing climate? When will the permafrost start to thaw? When does the thawed soil start to destabilize causing the street to subside and be damaged? With only a few alterations this model plug-in for roads can also be used to calculate scenarios for railway tracks and airstrips.
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There are not many roads in Alaska but all of them are important to transport goods and services into the remote Arctic areas. The Dalton Highways in Alaska is one of those roads. The Highway runs on a gravel embankment. It was built 3 meters high on top of the permafrost. The road is the only route of large truck transport to the oil operations in Prudhoe Bay at the Northern end of the highway. The PermaRisk team has measured the permafrost temperatures along the road and then modeled the permafrost thaw. The video in the next slide shows how the permafrost thaws beneath the road under a warming climate.
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When a flood damaged the Churchill railway in 2017 its repair took over a year and cost 117 million Canadian dollars. Today the train is running again. But the balance between people and nature in the Arctic remains fragile. Even small changes of the natural system can cause large disturbances in the lives of people and their livelihood.
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The permafrost risk
A project of the research group PermaRisk

The project was funded by the German Federal Ministry of Education.

Scenario, production and postproduction: denkbargruen and dsein

Design: dsein

Photo and Video:
The permafrost risk
Page 1, 2, 3, 10 - Moritz Langer
Page 4 - Thomas Opel
Page 5 - Annika Gutsche
Page 5 bis 9, 11, 14, 17 - Sina Muster
Page 12 - Thomas Schneider von Daimling
Page 13 - PermaRisk
Page 15 - Churchill Northern Studies Centre
Page 16 - Boris Radosavljevic, Thomas Opel, Konstanze PielPermafrost from afar
Page 1, 6, 7, 8 - PermaRisk
Page 2, 3 - Thomas Schneider von Daimling
Page 4, 5 - Sina Muster

Soil samples - Moritz Langer
Measuring lake depth - Moritz Langer
Scientist talks - Sina Muster, Moritz Langer

Sources:https://www.pc.gc.ca/en/pn-np/mb/wapusk
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Permafrost from the air

Every tree and bush, every pond is visible on the aerial images of the drone. Changes in the landscape can be measured centimeter by centimeter.
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Soraya Kaiser is a PhD student in the PermaRisk team. She uses the aerial images of the drone to map lakes in Canada and Alaska.
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When permafrost thaws at the shore of a lake, the shoreline erodes. The high-resolution aerial images show the shifting shorelines very well. They move 10 to 20 centimeters per year. This does not appear to be much but is highly relevant since there are millions of lakes all over the Arctic.

Soraya investigates the landscape properties that affect the lake erosion: How do size and shape of a lake affect the erosion? How do weather, ice content of the permafrost soil or the vegetation at the shore affect how fast the lake erodes?
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Soraya Kaiser

Ph.D. student at PermaRisk

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Vorher/Nacher Ansicht

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Soraya classifies the aerial images in order to map and measure land and lakes. The computer can almost automatically detect land and water in the image.

Click on Play in the bottom right corner and move the slider to compare the aerial image and its classification!
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The aerial images can also be used to measure the topography of the landscape. Topography describes the shape of the earth’s surface, its heights, depressions and slopes.
On expedition in the Arctic Soraya measures the height of the terrain at certain points and marks these points, their coordinates and height in the aerial images.
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Vorher/Nacher Ansicht

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Special calculation methods like the stereoscopy take several aerial images to determine the topography of the photographed landscape. The result is a digital elevation model.

Click on Play in the bottom right corner and move the slider to compare the aerial image with the elevation model!
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Vorher/Nacher Ansicht

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In the end, Soraya investigates how the landscape is changing. She compares classifications and elevation models for different years. Have the lakes grown or shrunk? Have new lakes formed or old ones disappeared? Where do the changes take place, how big are they and how fast did they happen? At the end of her PhD project Soraya will have answers to these questions.

Click on Play in the bottom right corner and compare two images from different years. Move the slider so find the differences in the landscape between  2006 and 2016!
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Bodenproben

Moritz takes soil samples. He wants to know how much air the soil holds, how fine or coarse the soil is, how wet it is and how much ice it contains in winter. All those properties determine how the permafrost absorbs the heat from the air and how it conducts the heat into the deeper soil layers. This in turn determines how fast and how deep the permafrost thaws during spring and summer.
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The remote-controlled Bathyboat measures the depth of the lakes. The shape of the lake bottom is also called the bathymetry.Lakes freeze to the bottom in winter when it is less than 2 meters deep. Is the lake deeper than 2 meters, then the bottom remains unfrozen. This is called a talik. The scientists need to know if there is a talik in the permafrost beneath a lake or not to correctly calculate the exchange of heat between the lake and the lake bottom.
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Videoclips Wissenschaftler

Thomas Schneider von Deimling, Ph.D.

Scientist at PermaRisk, Alfred Wegener Institute for Polar and Marine Research, Germany

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Stephan Jacobi

Engineer at PermaRisk, Alfred Wegener Institute for Polar and Marine Research, Germany

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Soraya Kaiser

Ph.D. student at PermaRisk, Alfred Wegener Institute for Polar and Marine Research, Germany

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Dr. Moritz Langer, Ph.D.

Research director of PermaRisk, Alfred Wegener Institute for Polar and Marine Research, Germany

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Prof. Scott Lamoureux, Ph.D.

Permafrost researcher at Queen's University, Kingston, Canada

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LeeAnn Fishback, Ph.D.

Scientific coordinator at the Churchill Northern Studies Centre, Canada

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