It rained heavily on Earth for a million years.

Dinosaurs in the Triassic Period

If you think Seattle in November is rainy, try living through the Carnian Pluvial Episode. Taking place some 232 million years ago, during the Triassic Period, it was a time of intense rainfall that lasted between 1 million and 2 million years. The prolonged, world-altering event was first discovered by geologists in the 1970s and ’80s. While studying ancient carbonate rocks in such far-flung locations as the Eastern Alps and the United Kingdom, they came across evidence of a deposit known as siliciclastic sedimentation that suggested unusually wet conditions. When it rains, it pours.

This period was preceded by an era of arid weather and coincided with the rise of the dinosaurs; the lush conditions that resulted helped the dinos thrive for another 150 million years or so. The Carnian Pluvial Episode wasn’t without its downsides, however. It appears to have been triggered by a series of massive volcanic eruptions that led to acid rain and an influx in greenhouse gases, which eventually brought about rapid climate change and mass extinctions.

By the Numbers

Did you know?

The rainiest place in the world is in India.

With an average of 39.4 inches of precipitation each year, Seattle isn’t actually that rainy in the grand scheme of things, despite its reputation. It doesn’t even crack the top 10 nationwide, because although it’s frequently damp, the city doesn’t see the heavy rains found in more humid areas or places where hurricanes are common. On a global scale, it’s even drier. Consider the wettest place on Earth for comparison: Mawsynram, India, which receives an incredible 467 inches of rainfall per year. Much of this comes during the monsoon season between July and September, which contributes to how lush and verdant the area is. Nearly as rainy is nearby Cherrapunji, also in the state of Meghalaya, as well as Tutunendo, Colombia.