Listening to Glacier Melt Sounds for Climate Change Monitoring

Key Quotes

"When glaciers form they form from snowfall high in the mountains and that process ends up trapping air bubbles as the snow gets compressed into ice and those little tiny bubbles travel through the glacier from way high up whether it's central greenland antarctica or just up in the mountains within the us and they eventually make their way all the way down to the end of the glacier and there's there's thousands millions quadrillions of them in there and as it melts out each little air bubble is pressurized because it's had this long journey and it just goes pop into the water and oscillates a little bit and so the sound will sound anywhere from the babbling brook which is what we just heard but if you're a little farther away and the ice is melting a little bit faster it can sound like a sizzling sizzling pan of food on the stove"

Dr. Aaron Pettit explains that the sounds of melting glaciers are caused by pressurized air bubbles trapped within the ice escaping as the glacier melts. She notes that the sound can vary from a babbling brook to a sizzling pan, depending on the rate of melting and the listener's distance. Pettit highlights that these sounds are a potential source of data for researchers studying climate change.

"Sound travels amazingly well in water so oceanographers have been using sound for a long long time to listen to what's going on in the ocean but until like 20 years ago nobody had ever thought to really look closely at what's going on at the terminus of a glacier and part of that's because it's really hard to get there like it's dangerous these cliffs are calving the ice is breaking off and forming icebergs there's just a lot going on and they can be quite dangerous to approach by boat or a ship and so we go up there and use sound because sound you can be back a little ways right you don't have to be quite as close to the glacier to really start to record some of the action happening"

Dr. Pettit discusses the advantage of using sound to study glaciers, drawing a parallel to oceanography's long-standing use of acoustics. She points out that the dangerous and inaccessible nature of glacier termini has historically limited close-up observation. Pettit explains that sound allows researchers to gather data from a safer distance, making it a more practical method for monitoring glacial activity.

"Wait why is it interesting to you it's interesting to me because we're losing ice everywhere in the world and it's really hard to keep track of how much we're losing and where we're losing it faster where it's melting faster where it's melting slower but that's really important to know so that we can start to one think about where that water goes when ice turns into water it contributes to the ocean and just being able to project into the future what do we think is going to happen next with these glaciers if they're melting if they're melting faster or slower underwater that affects how they're going to respond to changes in the future and we can put that into models we can think about it we can understand like just understanding the physics of what's going on is huge for starting to put that into perspective of how all the ice is changing on the earth"

Dr. Pettit emphasizes the scientific importance of understanding glacial melt rates due to global ice loss. She explains that tracking where and how quickly ice is melting is crucial for predicting where the meltwater will go and how glaciers will respond to future changes. Pettit states that understanding these physical processes is fundamental to modeling and comprehending the broader changes occurring across Earth's ice sheets.

"we actually have had pretty darn good success the four of us that are doing this this installation we like each other so that means that that like if somebody's messing up or something's going wrong we're we spend more time kind of laughing and trying to trying to get it right but we also are really scared because there's hundreds of thousands of dollars worth of equipment that we could lose so yeah it actually we practiced a lot on icebergs that are floating in a bit calmer water before going up to the glacier but when we we typically were successful like 50 of the time"

Dr. Pettit describes the collaborative and high-stakes nature of deploying their glacier monitoring equipment. She notes that the team's positive dynamic helps them navigate challenges, but the significant financial risk of losing equipment creates underlying tension. Pettit mentions that extensive practice on icebergs in calmer waters preceded their glacier deployments, where they achieved approximately 50% success.

"there certainly is i mean ice ice melting is part of the natural process like snow falls up high and then it melts or breaks off down low and so even in a climate in which we were growing glaciers we would still have sounds of ice melting but it is quite a bit more now than normal and we are listening to this ice loss that is not being recovered by snowfall up upstream and yes there is some melancholy to it there's a um it makes me just kind of think and reflect on the world around me and hopefully our whole society can think about and reflect on the world around us"

Dr. Pettit acknowledges the melancholy aspect of studying melting glaciers, distinguishing natural ice melt from current accelerated loss. She explains that while ice melt is a natural process, the current rate exceeds normal levels and is not being replenished by snowfall. Pettit suggests that this observation prompts personal reflection and hopes it encourages broader societal contemplation of the changing world.