New twist for obtaining grants: listen to sounds of glaciers to determine how much they shrink

From the AGU and the “why use direct measurements when we can get a grant to study a proxy” department. You can bet they’ll say things like “this glacier sounds distressed”.

Sounds of melting glaciers could reveal how fast they shrink

Posted by Lauren Lipuma

Scientists could potentially use the racket made by melting glaciers to estimate how fast they are disappearing, according to a new study of audio recordings captured in the waters of an Arctic fjord.

As glaciers melt, air bubbles trapped in the ice make popping or crackling sounds when they meet seawater, the same way ice cubes sizzle when placed in a warm drink.

New underwater recordings taken from Hornsund fjord in Svalbard, Norway, show melting icebergs make more noise the faster they melt. The recordings also distinguish melting sounds from grounded glaciers and floating icebergs.

The results suggest scientists could potentially use acoustics to track how fast Arctic glaciers are melting, according to a new study detailing the findings in Geophysical Research Letters, a journal of the American Geophysical Union.

Scientists typically measure glacier retreat by analyzing satellite data, but acoustic recordings would allow scientists to better understand what’s happening where the ice meets ocean water, an area difficult to observe with satellites.

Estimating glacier melt would help scientists better understand the effects of sea level rise, according to the researchers. The Arctic is warming at an unprecedented pace, and the melting of Arctic ice contributes to global sea level rise, which is currently about 3.4 millimeters (one-eighth of an inch) per year, according to NOAA.

“There is great possibility to use noise produced by bubbles trapped in glacier ice to study changing climate associated with iceberg melt and glacier melt,” said Oskar Glowacki, a geophysicist at Scripps Institution of Oceanography at the University of California San Diego and lead author of the new study.

“These tiny air bubbles are singing songs, and these songs are the songs of the changing climate.”

Listening for sounds of change

Pockets of air between snowflakes get trapped and compressed over time as layers of snow build up and condense into ice to form glaciers. Icebergs break off glaciers where the ice meets the sea.

Acoustic recordings made near drifting icebergs in the early 1970s showed ice “sizzles” when it melts, as the air bubbles trapped in the ice explode into seawater. Research published in 2015 showed melting glaciers are the loudest places in the ocean and scientists could potentially use this noise to study the melting ice.

In the new study, Glowacki and colleagues from Scripps and the Polish Academy of Sciences in Warsaw placed microphones that can record underwater in Hornsund fjord during the summers of 2013, 2015 and 2016. They wanted to capture sounds of melting glaciers within the fjord to see if they could use the noise as a proxy for how fast the glaciers were melting. They also wanted to see if they could distinguish between sounds made by melting icebergs and those made by the glaciers themselves.

The researchers found the hiss of melting icebergs is slightly different than the sound of melting glaciers. Recordings of the glaciers revealed the explosions of bubbles into seawater were continuous, like rain hitting the surface of a lake.

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Tom Halla

Is this to be a tool used by Feminist Glaciologists?snark

Curious George

Ms Lipuna is aPR person for AGU, not an author.

Caligula Jones

Great. We haven’t settled the “Yanni” vs. “Laurel” stuff and now they want to turn it into science?

Here is the video:
I’m Melting!

knr

The Arctic is warming at an unprecedented pace, warning BS alter , close the blast doors.

Vey low signal to noise ratio comment, knr? Possibly negative?

Nothing like a Glacial Shrink to measure glacial shrink. A whole new area of psychiatry.

ResourceGuy

Save travel expenses and CO2 emissions and just use voices in your head instead.

Sure sounds like water movement.

Wrusssr

They’ll have to switch ears regularly. Hard to hold one against a glacier more than a minute or two. How much did they say there getting to do this?

Old44

One thing puzzles me about melting glaciers contributing to sea level rises.
Where did the ice in the glaciers come from in the first place?

Alan Tomalty

The oceans where else?
Water does not get created or destroyed in nature except by nuclear fusion processes as in the SUN.

John Bell

Not exactly, Alan, when you drive your car you are making water, combustion makes water as do other processes.

Ve2

It was a rhetorical question.

Mark from the Midwest

I’ve been involved with obtaining audio signatures with something as well known as the English language. You need 100’s of millions of comparative tests before you can be sure that the measurement error is in check. This is an area that is ripe for all kinds of shenanigans.

tty

Everybody who has ever taken a boating trip near a glacier front knows this and recognizes the sound. However there are a number of complications:
The thickness of the glacier. The air in the snow/firn/ice only form discrete bubbles at a depth of c. 300 feet, so no noise from the upper part of the glacier.
The strength of the “pop” depends on the air pressure in the bubble, so is not constant per cubic meter of ice.
The amount of ice melting per time unit does not depend exclusively on the amount of calved ice but also on water temperature, salinity, air temperature and insolation.
And the killer problem. Most of the ice that calves from a glacier does not melt nearby. It sails off in the form of icebergs and can drift thousands of kilometers, popping all the way. It would be rather expensive to fit a mike and a satellite transmitter to each and every iceberg, growler and bergy bit.
And finally: WHY. The amount of ice calving from a glacier can be estimated with good accuracy simply by measuring the movement of the glacier plus a profile across the glacier snout, both fairly straightforward and done routinely by glaciologists.

WXcycles

Bucket of someone’s cash goin’ begging.

Best be very aware of scientific co-workers who might be chomping on popcorn in the background, or chewing gum — you have to filter out this noise, of course, to get accurate readings.
We should do a re-write of Prince’s When Doves Cry that includes the line, This is what it sounds like when Earth cries.
Sorry I can’t be more supportive.

Tom in Florida

How do we know that wasn’t recorded in a men’s room at the Super Bowl?

Yeah, how do you authenticate audio recordings of melting ice? … guarantee quality? … free of possible mechanical noise within the environment or within the recording equipment/playback ensemble? … chain of handling? … guarantee of no post-production enhancement? … quality-controlled to match a set of standards, whereby everybody recording crying ice does it the same standard way?

James Bull

My first thought when I heard it was this which about follows your comment.

James Bull

ossqss

Hummm, sounds like fish farts to me! ; -)
Your Fired!

tty

No, the sound actually exists. You can hear it quite well from a boat close to a calving glacier, though above the surface you only hear near-by “popping”, so you can distinguish each individual “pop”.

Smart Rock

They are very carefully not mentioning that all glaciers flow downhill, and most of them end up at the sea, where they start to melt and big chunks (icebergs) break off and float away. So they will get noise from all glaciers that meet the sea.
I think this will be the kind of soft, malleable data that can be interpreted manipulated to support any conclusion (and I’ve got $50* that says I know what that conclusion will be)
* – Canadian $

tty

“and most of them end up at the sea”
Not really. Tidewater glaciers practically only occur in arctic areas (exceptions southern Alaska and southern Chile). A large majority of all glaciers melt before reaching sea-level.

Wrusssr

What? Glaciers melt?

tty

Measuring calving this way would also be something of a long-time project at least in Antarctica. Take Iceberg B-9 for example (the one that messed things up for the “Ship of Fools” expedition). It calved from the Ross Shelf in October 1987 and is still around 30 years and 6 months later. Of course it has shrunk a lot. It’s hardly even as large as Rhode Island now, orignally it was bigger than Delaware.

Steve Zell

So, to determine the ice loss rate per year, you have to divide the iceberg volume by 30 or 60?

s-t

This “invention” reminds me of Prof. John I.Q. Nerdelbaum Frink.
https://youtu.be/KLmJzQPQfdI?t=4m57s

Alan Tomalty

ABSOLUTE MADNESS

Henning Nielsen

To get a real close sound experience, go to the bottom of a deep crack.

tty

No need to. A moving glacier is fairly noisy. A surging glacier is very noisy.

Steve Zell

Who wants a grant to be an ice whisperer?

michael hart

Sounds cool.
I’ll get my coat.

M Courtney

It’s a real observation.
They are trying to develop a new way of learning about the world.
This is real science. Save the mockery for those models that are not looking at the real world.

tty

It’s an utterly trivial observation. As I’ve said before, anybody who has been close to a calving ice-front knows about it. And to use it for determining the amount of calving is impractical.

M Courtney

Anyone who’s been near a boiling kettle knows that the lid moves.
That’s not the same as trying to quantify the effect.
If the hoped for endgame is impractical then it won’t happen. But something else might. This is real science as it’s about looking at the real world.

Pamela Gray

But apparently genetically modified elephants using wooly mammoth DNA could help reduce permafrost melting! What would be the harm in that?

Aurora Negra

So the glaciers make noise? Sure they do! In water in front of a calving glacier it sound like white noise from an electric system. In your tent 100 m away from a calving glacier it is a nice sound to put you to sleep. But if you really want to listen to a glacier you need to be high up where the temperature is -40 C(or F) the wind is 40 miles/hr and where the most pleasant place is deep down in a crevasse. It’s an experience to try to sleep when the glacier go BANG, BOOM,CRACKLE all around you. You just have to reassure yourself that the statistical chance or the crevasse closing on you is somewhat small. And the sound of a waterfall inside a glacier is actually more intimidating than the Niagara falls. And finally the wind howling through crevasses and tunnels makes a nice piece of music. But how do you make science out of all this? Beats me!

DGP

We called it “bergy seltzer” in the Navy. I’ve heard it but I don’t know how you could tie it to melt rate, which would be affected by other factors like surface area.

DGP

Also, wouldn’t more of the glacier be subject to melting more as it was growing and more of it comes into contact with the sea?