Journal

”I was told my plan was impossible, so I decided to name it Project Possible. It doesn’t matter where you come from. You can show the world nothing is impossible.” Nims Purja

An upwelling plume area at the face of Kongsvegen Glacier. Ny Ålesund, Svalbard, Norway. Photo by Xander Kirshen, Courtesy of Mark Goldner (PolarTREC 2021), Courtesy of ARCUS

The Uncertainty of GlacierA mass of ice that persists for many years and notably deforms and flows under the influence of gravity. Dynamics

I was introduced to Nims Purja while viewing the documentary 14 Peaks the other day. It brought to mind the really huge unknowns and impossibilities scientists studying glaciers in the Arctic have experienced so far in knowing how glacial meltwater influences speed and amount of ice flow and the rate of mass loss from the Greenland ice sheet into oceans. This is a key uncertainty in the study of glacier ice dynamics, one that this expedition is trying to understand.

Diagram courtesy of Dr. Sarah Das, Woods Hole Oceanographic Institution

Think about it like this. Meltwater goes from the surface of the glacier into cracks and holes down to the bottom of the ice. This water causes the glacier to slide more easily over the rock underneath. We can’t see the water at the bottom of the glacier, so we are trying to use instruments to map out where the water goes and how quickly the ice moves. These instruments are called seismic tremor arrays.

How To Test A Hypothesis

During the Han Dynasty in China, the world’s first seismoscope was invented which measured seasonal winds and movements of the earth. Like its predecessor, a modern seismometer is an instrument that responds to ground noise and shaking caused by earthquakes, volcanic eruptions, or explosions. A seismic array is a system of linked seismometers arranged in a geometric pattern to detect earthquakes or explosions.

Ancient Chinese seismoscope. Photo taken from Ancient Origins Website

The expedition team will be setting up seismic and GPSA Global Positioning System (GPS) is a satellite-based navigation system used to track the location or position of objects on the Earth’s surface. arrays, which mean systems of linked seismometers arranged in patterns to detect movement, in this case not of earthquakes or explosions, but of glacial meltwater.

Photo courtesy of Dr. Sarah Das, Woods Hole Oceanographic Institution.

The hypothesis in this case is that there are pools and rivers that form under the glacier, and that are changing over time. The form the water takes will have a different effect on how easily the glacier above can slide over the rock below. Is there a lot of water or a little? Does it form rivers or ponds? Are there a lot of little streams or one big river? These are some of the questions this technology will hopefully help to answer.

Diagram courtesy of Dr. Sarah Das, Woods Hole Oceanographic Institution.

Water at the bottom of the glacier can’t be seen since it is under 1000 meters of ice. Seismic tremor and GPSA Global Positioning System (GPS) is a satellite-based navigation system used to track the location or position of objects on the Earth’s surface. arrays record the vibrations of the water as it moves under the ice. Scientists can then use these measurements to help map out where the water goes and how that changes between the winter and summer. We will also be measuring how quickly the ice on the surface moves at the same time. The hope is to connect these observations together to help better understand how quickly the Greenland ice sheet is changing.

Sea level rise is projected to affect at least 132 Maine cities, and towns that lie on Wabanaki ancestral homelands. Photo of ArcGIS Map created by Erin Towns

Findings may help nations and towns plan and mitigate effects of a melting ice sheet. Sea level rise is projected to affect at least 132 Maine cities, and towns that lie on Wabanaki ancestral homelands, affecting coastal businesses, homes, wildlife habitat, transportation systems, and some of the state’s treasured places according to an analysis done by the Natural Resources Council of Maine. A 1-meter rise is projected to take out over 20,000 acres and a 6-meter rise, over 127,000 acres.

From what I’ve learned scientists, although not climbing 14 peaks in 6 months and breaking world records, do set out to do the impossible everyday by thinking out of the box, brainstorming, asking questions, and figuring it out. And they never stop. They attempt and sometimes are successful at doing the impossible everyday and dedicate their entire lives to this work.

Student Corner

What evidence of climate warming do we see in the Gulf of Maine according to what you learned last class using the Gulf of Maine Explained videos? Answer below in the comments section. Leave a question about what you read above for the team to answer!

Details
Author
Erin Towns
Date
Location
Ilulissat, Greenland
Expedition
Greenland Subglacial Tremor Project

View Comments

Comments

Wed, 04/13/2022 - 04:51

Ansley W

How long does it take to set up the seismometer?

Thu, 04/14/2022 - 07:19

Ansley W

We can see climate change in Maine from sea levels rising.

Thu, 05/05/2022 - 06:25

Dr. Sarah Das

When ice melts in Greenland, most of this water goes into the ocean where it contributes to sea level rise. But sea level does not change equally around the world! In fact, while rates of sea level rise around Maine are some of the highest globally (leading to flooding, erosion, and loss of important ecosystems such as salt marshes), relative sea level (meaning how the height of the ocean rises or falls relative to the land at a particular location) is falling around parts of Greenland because the land itself is rising (in response to the loss of ice weighing it down) faster than the absolute ocean level!

Thu, 05/05/2022 - 04:30

Dr. Mark Behn

When were first started it took about 2.5 hours, but as we get better we are hoping to be able to set up a complete station in an hour and a half.

Wed, 04/13/2022 - 05:48

Melanie S

What will you guys do if you find large amounts of water under the glaciers?

Thu, 04/14/2022 - 05:45

Kayla T

How long will it for glaciers to fully melt?

Thu, 04/14/2022 - 05:46

Kayla T

How long will it take for glaciers to fully melt?

Thu, 05/05/2022 - 06:25

Dr. Sarah Das

Glaciers all around the world are rapidly melting due to warming temperatures from climate change. To understand the past, we use clues preserved in the ice, on land, and in lake and ocean sediments to piece together how large or small glaciers and ice sheets were, and what was causing these changes (hint: it’s a combination of changes in temperature and snowfall). Greenland has been at least partially covered by ice for hundreds of thousands of years, perhaps even more than a million years. But its size has changed a lot, in particular between colder snowier glacial (ice age) periods and warmer (interglacial) periods such as we are in today.

Thu, 04/14/2022 - 05:46

Leia Ross

What are your guises plans if you find water under the glaciers small or big?

Thu, 04/14/2022 - 05:48

Kendra L

Is it bad if theres water in the glacier?

Thu, 04/14/2022 - 05:53

Jenny C.

what will happen if there is a lot of water under the glacier? do you guys have a plan if that is the case?

Thu, 04/14/2022 - 07:17

Leah B.

if there is water under the glacier with is come out from under you?

Thu, 05/05/2022 - 04:34

Dr. Mark Behn

We think that the water acts as a lubricant that helps the glacier slide faster than if there was no water at the bed. Imagine that the ice sheet is a giant pancake — where you pour the batter at the center and it flows out toward the edges. If you greased the pan before pouring out the batter it would slide outward faster. The batter in our case is the new snow that falls at the center of the ice sheet and turns into ice. The grease is the meltwater at the bed of the ice sheet. In general, we think there is more meltwater under the edges of the ice sheet than near the center. This allows the ice near the edges to slide faster.

Thu, 04/14/2022 - 07:18

Jenny C.

how long does it take to get the measurements from the seismic and Gps?

Thu, 05/05/2022 - 04:34

Dr. Mark Behn

The instruments begin recording data immediately. However, our instruments are not able to send data back to us remotely. So instead we will have to wait until August when we come back to ice sheet to recover the instruments and download the data.

Thu, 04/14/2022 - 07:22

Shawn H

So, does the seismometer array work like a form of sonar, listening to the sound of the water down there?

Thu, 05/05/2022 - 04:35

Dr. Mark Behn

Seismometers recording shaking at the surface of the ice sheet. The shaking can be caused by small earthquakes (or icequakes) in the ice sheet or between the ice and the bedrock below. Meltwater streams can also cause shaking at the surface of the ice sheet. We can use our seismic arrays like an antenna to determine the direction and distance the source of the shaking is away from the array. In this way we hope to map out meltwater streams at the base of the ice sheet and correlate those streams to how fast the ice is moving.

Thu, 04/14/2022 - 07:27

Mikaila Marks

How did scientists figure out glacial meltwater could be detected from movement such as earthquakes could?

Thu, 04/14/2022 - 07:33

Mikaila Marks

We can see climate change in the Gulf of Maine from the water currents shifting and warm Golf Stream waters heading north

Thu, 05/05/2022 - 04:37

Dr. Mark Behn

In mountain glaciers, scientists have correlated the magnitude of the shaking (sometimes called seismic tremor) to the rate of meltwater discharge at the edge of the glacier. Further, in mountain rivers scientists have correlated seismic tremor to the rate of stream flow as measured by a stream gauge. The new idea we are testing with this project is whether this can be done through almost a kilometer of ice, and also whether we can use our seismic arrays to map out where the river channels are located.

Thu, 04/14/2022 - 07:28

Madisyn S

What would happen if you don't see much water or to much under the glaciers

Thu, 04/14/2022 - 07:29

Avery O.

How did the Han Dynasty come up with the seismoscope?

Thu, 04/14/2022 - 07:30

Lila D

How big is the seismic? Are you able to set it up with just one person?

Thu, 04/14/2022 - 07:37

Kasey S.

Evidence of glaciers in Maine are things like sand/gravel pits, any mountains with rounded tops, and cirques. What is your current hypothesis about the flow of the water?

Thu, 05/05/2022 - 04:37

Dr. Mark Behn

In the region we are working, the ice sheet moves fastest early in the summer and then slows down in the later part of the summer. This is interesting because we expect the amount of water supplied to the bed to be about the same throughout the summer. So why does the ice slow down? Scientists think that early in the summer meltwater is widely distributed across the entire bed of the ice sheet, and act as a lubricant that helps facilitate sliding of the ice. However, as the summer progresses that meltwater is focused into large channels (or river systems). These rivers can more quickly drain the meltwater away from the bed and therefore reduce the lubrication at the bed. This causes the ice to slow down even though there is still lots of meltwater entering the bed.

Fri, 04/15/2022 - 18:05

Regina Brinker

Erin, I'm enjoying the stories, images, and detail of your post. I'm looking forward to following your expedition .

Nims Purja is an inspiring - and very fit - mountaineer. What an accomplishment for him and his team.

Mon, 05/02/2022 - 02:34

Erin T

He is amazing. And thank you Regina! So glad you are following along!

Mon, 05/02/2022 - 02:35

Erin T

Thanks Janet! Thank you all for your support and help :)))