From Watts Up With That?

By Anthony Watts

New paleo evidence reveals floods in Earth’s past that were hundreds of times larger than anything we’ve seen recently — and had nothing to do with CO₂.

“The past is not dead. It’s not even past.”
— William Faulkner

The media’s appetite for climate catastrophe never seems to get full. Virtually every flood event now comes packaged with breathless declarations of “unprecedented” intensity and grim warnings of fossil-fueled doom. But a new study covered by Phys.org just threw a mammoth-sized monkey wrench into that narrative — quite literally.

Researchers examining Paleo flood evidence in the Pacific Northwest have found that ancient deluges during the last Ice Age were not just bigger, they were so massive that they make modern floods look like puddle-jumping. In some cases, peak discharges exceeded 10 million cubic meters per second, compared to just tens of thousands for modern floods — including extreme ones like the 1993 Mississippi River flood.

Let’s be clear: these were natural events, happening 12,000 to 18,000 years ago, long before coal plants, internal combustion engines, or UN climate conferences.

The new study builds on decades of work around the Missoula Floods — a series of truly biblical floods unleashed when glacial ice dams repeatedly failed, releasing the waters of Glacial Lake Missoula across eastern Washington and beyond. These floods:

• Moved boulders the size of houses,
• Left behind giant ripple marks visible from the air,
• Carved out entire canyons and scab-lands,
• Created sediment fans and slackwater deposits hundreds of feet deep.

Modern researchers are now using LiDAR, stratigraphy, and radiocarbon dating to map these features in exquisite detail — and what they’re finding is unmistakable: nature has produced floods on a scale we can barely comprehend, entirely without the help of SUVs, coal power plants, or increased atmospheric CO₂.

---

Why This Changes the Flood Narrative 

1. “Unprecedented”? Not Even Close.

2. Natural Variability Still Reigns Supreme

One of the most abused words in climate reporting is “unprecedented.” We saw it used in the wake of the Pakistan floods in 2022, the German floods of 2021, and countless others. But paleo-hydrological data remind us that extreme floods are not new, and they are not inherently human-caused.

Labeling every modern flood as evidence of climate breakdown, without acknowledging the geological record, is either bad science or bad faith — sometimes both.

2. Natural Variability Still Reigns Supreme

What this new study really underscores is something skeptics have been saying for years: you cannot meaningfully assess modern extremes without understanding natural variability. The Earth’s climate and hydrologic systems have long been capable of producing massive, abrupt, and destructive events. Pretending otherwise is a political act, not a scientific one.

It’s also worth noting that attribution science — the process by which modelers “link” extreme events to climate change — typically relies on modern observational datasets going back only to the 1950s or so. These models almost never account for long-term geologic-scale extremes, like those revealed in studies like this one. That’s a glaring omission, and one that calls into question the reliability of claims like “climate change made this flood worse.”

Related: Attribution science’s weak foundations

---

Models Can’t Handle This Scale of Flooding

Let’s be blunt: if a flood today rivaled the scale of the Missoula outbursts, every climate model would be off the charts — and every climate reporter would blame it on carbon emissions. But these floods happened naturally. They were driven by glacial mechanics, not greenhouse gases.

If your climate model cannot reproduce the known history of past megafloods, why should we trust its projections for the year 2100?

---

Final Thoughts: A Lesson in Humility

This new study serves as a powerful reminder that the natural world is not tame, not linear, and not bound by human carbon cycles. It has produced extremes far beyond what we’ve seen in our brief observational window.

So the next time someone insists that a big flood is proof of man-made climate collapse or crisis, or the doom de jour, send them a link to this study. Then ask them why they’re ignoring the evidence carved into the Earth itself.

And remember: history didn’t start in 1979 — even if most climate narratives do.

---

Further Reading:

• Missoula Floods – USGS Overview
• LiDAR Mapping of Pleistocene Flood Channels
• WUWT on Extreme Weather Attribution

Want to see more skeptical deep dives like this? Subscribe to wattsupwiththat.com and support independent science journalism that questions the climate narrative – plus get exclusive content available only to subscribers.