What Happens When Lakes Stop Mixing
The Quanta Podcast
Quanta Magazine
4.7 • 638 Ratings
🗓️ 2 December 2025
⏱️ 31 minutes
🧾️ Download transcript
Summary
Every summer since 1983, scientists at Crater Lake National Park have gathered data about the lake’s famous clarity. This past summer, Quanta contributing writer Rachel Nuwer journeyed with them as they conducted their annual tests. On this week’s episode, Nuwer and host Samir Patel discuss what gives the lake its vivid blue color, and what its data can tell us about the way water moves through a deep temperate lake.
Each week on The Quanta Podcast, Quanta Magazine editor in chief Samir Patel speaks with the people behind the award-winning publication to navigate through some of the most important and mind-expanding questions in science and math.
Audio coda recorded at Crater Lake National Park in July 2010 by the National Park Service Natural Sounds Program.
Transcript
Click on a timestamp to play from that location
| 0:00.0 | Johannes Phocas was a Greek explorer who sailed for the Spanish crown in the late 16th century. |
| 0:10.0 | They knew him by the name Juan da Fouca. |
| 0:13.0 | It's not entirely clear what he may or may not have, quote, discovered on his voyages, |
| 0:19.0 | but his name did get assigned to the straight of water between |
| 0:23.2 | Vancouver Island and the Olympic Peninsula. |
| 0:26.8 | From there, he got an underwater ridge offshore named after him, and then he was truly |
| 0:33.1 | etched in geologic history when his name got put on a tectonic plate. |
| 0:38.3 | The Juan Defuca plate is crammed between the Pacific Plate and the North American continent. |
| 0:43.3 | It's getting pushed beneath the continent where it melts, and it's responsible for the volcanic activity that created the Cascade Range. |
| 0:52.3 | That's Mount Baker, Mount Rainier, Mount St. Helens. |
| 0:56.1 | And among those volcanoes is another called Mount Mazama, |
| 0:59.3 | which once stood at about 12,000 feet. |
| 1:02.9 | Around 8,000 years ago, Mount Mazama blew its top. |
| 1:07.1 | This eruption, which is preserved in the legends of the Klamath people, |
| 1:13.6 | took almost a mile off the top of the mountain, which then collapsed into a caldera that, over the next several hundred years, filled with crystal clear water. |
| 1:20.6 | That's the origin story of Crater Lake, the deepest lake in the United States, with some of the purest fresh |
| 1:28.2 | water in the world and a gem of the National Park System. |
| 1:33.0 | It's also one of the best studied lakes in the world with detailed data going back more |
| 1:37.6 | than a hundred years. |
| 1:39.6 | And that makes Crater Lake a very interesting place to understand how lakes are changing all over the world. |
| 1:51.0 | Welcome to the Quanta podcast where we explore the frontiers of fundamental science and math. |
| 1:57.0 | I'm Samira Patel, editor-in-chief of Quantum Magazine. |
... |
Please login to see the full transcript.
Disclaimer: The podcast and artwork embedded on this page are from Quanta Magazine, and are the property of its owner and not affiliated with or endorsed by Tapesearch.
Generated transcripts are the property of Quanta Magazine and are distributed freely under the Fair Use doctrine. Transcripts generated by Tapesearch are not guaranteed to be accurate.
Copyright © Tapesearch 2026.