Short Wave – "Nature Quest: The Earthquake Prediction Problem"

Hosts: Emily Kwong and Hannah Chin
Date: November 25, 2025
Duration: ~15 minutes

Episode Overview

This episode of Short Wave takes listeners on a "Nature Quest" to explore the challenge of earthquake prediction, focusing on the Pacific Northwest's looming "Big One." Producer Hannah Chin (Portland native) leverages her "producer privilege" to investigate why—despite deep knowledge about the likely impact of major quakes—scientists still cannot say when the next catastrophic earthquake will come. The hosts delve into geology, seismology, tsunamis, folklore, and the practical responses people can take, all while maintaining Short Wave’s signature blend of approachable science and wry humor.

Key Discussion Points & Insights

1. The Cascadia Subduction Zone and “The Big One”

• Cascadia Subduction Zone: An underwater fault stretching from Canada to Northern California.
• Residents, especially in Portland, live with the anxiety of “the Big One”—a potentially magnitude 8 or 9 earthquake.
• First-Person Experience:
  • "Portland is not a hotspot for earthquakes... But as long as I can remember, Portlanders have known that an earthquake is coming. When we talk about it, we call it the Big One." – Hannah Chin [00:48]

2. What Would a Massive Earthquake Feel Like?

• Expert: Diego Melgar, Director of the Cascadia Region Earthquake Science Center
  • "You would feel shaking, where it's difficult, maybe even impossible for you to stay standing for anywhere between one or three minutes. Start counting right now and realize how long that is." [01:39]
  • Massive infrastructure damage: bridges collapsing, landslides covering major roads, utility failures, soil liquefaction [01:51].

3. The Impossibility of Earthquake Prediction

• Despite knowing a lot about the effects of earthquakes, predicting their timing remains out of reach.
• Expert: Chris Goldfinger, Marine Geologist and Paleoseismologist, Oregon State University
  • "Prediction is sort of, in the science world, as we call it, the P word. We just don't really even speak about it because nobody can do it." [02:34]
• The hosts and experts discuss the humility and frustration around this scientific limitation.

4. How Do We Know a Big Quake Is Past Due?

Clues in both Geology and History

• Ghost forests and sand deposits on the Oregon-Washington coast provide geological evidence of past major events [04:37].
• Japanese Historical Records:
  • The "orphan tsunami" of January 26, 1700, recorded by Japanese scholars who noticed a tsunami with no local earthquake source [05:09]. -:Chris Goldfinger:
    • “This tsunami arrived out of nowhere with no earthquake to go with it, no warning. It killed a few people, destroyed some boats…and they had written records of this.” [05:33]
• Detective Work:
  • Modeling linked the orphan tsunami to Cascadia, allowing an exact dating of the last major Northwest quake: Jan 26, 1700, about 9 p.m. [06:12].

5. Earthquake Timing: The “Chaotic Turkey” Metaphor

• Averages are Misleading:
  • Magnitude 9 earthquakes happen every ~500 years on average, but intervals can vary wildly.
  • "Earthquakes can cluster in time…It is not the case that they happen ‘500 years, nothing, earthquake.’ That’s not how Earth works. I wish it were." – Diego Melgar [07:04].
• Memorable Metaphor:
  • Chris likens earthquake timing to turkey in the oven with no thermometer or timer:
    • “You have no way of measuring when the cycle started or how far into it you are or how cooked it is.” [07:56]

6. What CAN Scientists Predict?

Understanding Effects, Not Timing

• Excellent ability to model and predict tsunami size, shaking patterns, and infrastructure risk scenarios [08:35–09:04].
• How?
  • By reading sediment core samples—like tree rings for the landscape.
  • Tina Dura, Coastal Geologist and Paleoseismologist, Virginia Tech:
    • "When we have a big Cascadia earthquake, tsunami washes in sand and deposits it on these marshes... And in some of these marshes, we have up to a 7,000 year record of past earthquakes.” [09:15 and 09:35]
• The interplay of rising land (tectonic uplift) and the sudden, dramatic changes after a quake.
  • The next quake could cause land to drop by up to 2 meters in minutes, leading to sudden, severe flooding—especially in low-lying coastal communities [10:34–10:47].

7. Linked Faults: The Domino Effect

• Cascadia Subduction Zone and California’s San Andreas Fault are “seismically linked.”
• Cascadia could trigger quakes on San Andreas and vice versa—“a big bad set of dominoes, just like tipping down the West Coast.” [12:21]

8. Hope: Earthquake Early Warning Systems

• Technology has progressed: Early warning networks with thousands of sensors can detect the tiniest initial tremors.
  • "We need seismometers, sensors that feel the first teeny Tiny vibrations." – Diego Melgar [12:46]
• Within 15–20 seconds of the first signals, emergency alerts can go out to phones and sirens, giving people precious—but brief—time to seek cover [13:36].
• "Even a little bit of advanced warning could be the difference between life and death." – Emily Kwong [13:43]

9. Knowledge is Power: What You Can Do

• Armed with accurate knowledge about earthquake and tsunami risk, people and communities can prepare.
  • "Knowledge is power, and I'd rather know that these are the challenges we're facing... Because armed with that knowledge, I can develop goals and objectives." – Diego Melgar [14:02]
• Personal and community preparation are key: planning, local networks, pushing for safer buildings and emergency plans [14:18].

Notable Quotes & Memorable Moments

• “Prediction is sort of, in the science world, as we call it, the P word. We just don't really even speak about it because nobody can do it.” – Chris Goldfinger [02:34]
• “You would feel shaking, where it's difficult, maybe even impossible for you to stay standing for anywhere between one or three minutes.” – Diego Melgar [01:39]
• “Earthquakes are like chaotic turkeys.” – Emily Kwong, riffing off Chris Goldfinger’s metaphor [08:15]
• “The tsunami arrived out of nowhere with no earthquake to go with it, no warning.” – Chris Goldfinger [05:33]
• “15 to 20 seconds... even a little bit of advanced warning could be the difference between life and death.” – Emily Kwong [13:43]
• “Knowledge is power... I'd rather know that these are the challenges we're facing.” – Diego Melgar [14:02]

Key Timestamps

• 00:48–01:19: Hannah explains Portland’s anxiety about “the Big One.”
• 01:39–01:58: Diego Melgar on what a major quake would feel like.
• 02:34: Chris Goldfinger on why scientists avoid the word “prediction.”
• 05:09–06:12: The orphan tsunami in Japanese records leads to exact dating of last Big One.
• 07:04: Explanation of why average intervals are misleading.
• 07:56: Chris Goldfinger’s turkey-in-the-oven earthquake analogy.
• 09:15–09:35: Tina Dura on reading sediment cores for quake history.
• 10:34: Sudden land drop and flood risk explained.
• 12:21: How Cascadia and San Andreas faults can trigger each other.
• 12:46–13:36: How the West Coast’s earthquake early warning system works.
• 14:02: The vital importance of knowledge and community action.

Final Takeaways

• Earthquake timing is fundamentally unpredictable, but modeling of impacts has advanced immensely.
• Community preparedness makes a difference: knowledge, planning, and robust public safety advocacy matter.
• Early warning tech is improving—but every second counts.

The episode leaves listeners alert but empowered: we may not know when the Big One will come, but we can be prepared for what it will bring.