Hosts: Kate Lamble & Jordan Dunbar
Guests: Jemma Wadham | Professor of Glaciology | University of Bristol &
Natalya Idrisova | Project Coordinator | The Little Earth
Category: 🔬 Research
Podcast’s Essential Bites:
[1:36] KL: “Around 10% of the world's population lives close to what's known as the cryosphere, areas where water is frozen solid.”
[1:44] JD: “As the world warms almost 270 billion tons of ice is melting away from […] glaciers every year.”
[5:14] JW: “Glaciers during the summertime in the mountains or a dry period, they are melting, that's a natural process. The surface of the glacier is warmed and the ice melts. But then what happens in between times is you might have a cold period of winter, where the glass here stops melting, and then it starts to accumulate snow, and that's it's a nourishment.”
[5:41] JW: “You need a balance between the amount of snow that falls and accumulates on the glacier. And the amount that then melts in the summer. If those two things are out of balance, then you either have a growing glacier, there's too much snow or a shrinking glacier, there's too much melt. So we're in the situation of shrinking glaciers at the moment, because the melt is winning over the snowfall.”
[6:27] JW: “In the Himalayas, […] people have predicted that if we kept to 1.5 degrees, you might lose a third of Himalayan glaciers. If we carried on as usual, you could lose two thirds of the glaciers. Some people think that our ice sheets might actually become unstable upwards of 2 degrees. So the important thing is every fraction of the degree matters to a glacier.”
[6:47] JD: “In Tajikistan 20% of the glaciers have melted in the last 40 years.”
[9:50] JW: “So the thing about glaciers when they melt is water doesn't always just go straight into the rivers and rundown into the oceans, it gets trapped. And […] glaciers erode their landscapes, they create these holes and depressions. […] [And these gaps can fill with water.] And those lakes […] are not stable. What can happen is they can get to the point where they essentially breach their dam. And then they cause these huge floods, which are called glacier lake outburst floods or GLOFs, and they can be very sudden, release enormous amounts of water, and create a threat for village communities.”
[10:39] KL: “One recent glacial lake outburst flood in Chile caused the river to rise by 10 meters, which is just terrifying. […] It's about the height of a three storey building.”
[12:14] NI: “About 70% of people [in Tajikistan] live below the poverty line. […] Many mountainous regions of the country are still either not electrified or facing a lack of electricity. That's why local residents have to cut down vegetation around for cooking and heating their houses. So deforestation seriously worsens the ecological situation in the country and leads to more destructive landslides and mudflows.”
[16:01] JW: “If you go right up into the headwaters of the major river systems that are fed by glacial melt water, you can find those rivers are actually mostly melt water. But as the glaciers become smaller, in the coming decades, that melt water supply will start to shut off. So if you go to somewhere like the Peruvian Andes, the glaciers there come so small that the amount of meltwater being fed into the rivers has gone down by like a third in the last few decades.”
[17:14] KL: “While melting glaciers might initially mean more water entering the system. Eventually, when it finally disappeared, you'd be left with droughts rather than floods.”
[20:27] JD: “As a glacier naturally melts, they drip onto land in front of them, and it often creates a kind of soggy, boggy patch known as a wetland.”
[20:35] KL: “Wetlands slow water down, reducing flood risks, and they release water slowly during the summer months. Perfect to recreate some of the effects of the natural glacier cycle, which mountain communities rely on. [Therefore high altitude wetlands need to be protected].”
Rating: 💧💧
🎙️ Full Episode: Apple | Spotify
🕰️ 27 min | 🗓️ 02/21/2022
✅ Time saved: 25 min
