What's the hottest Earth's ever been?
Author:
Michon Scott
Rebecca Lindsey
June 18, 2020
This article was first published in August 2014, and it has been updated to include new research published since then. This article is one of a two-part series on past temperatures, including how warm the Earth has been “lately.â€
Our 4.54-billion-year-old planet probably experienced its hottest temperatures in its earliest days, when it was still colliding with other rocky debris (planetesimals) careening around the solar system. The heat of these collisions would have kept Earth molten, with top-of-the-atmosphere temperatures upward of 3,600° Fahrenheit.
Even after those first scorching millennia, however, the planet has often been much warmer than it is now. One of the warmest times was during the geologic period known as the Neoproterozoic, between 600 and 800 million years ago. Conditions were also frequently sweltering between 500 million and 250 million years ago. And within the last 100 million years, two major heat spikes occurred: the Cretaceous Hot Greenhouse (about 92 million years ago), and the Paleocene-Eocene Thermal Maximum (about 56 million years ago).
https://www.climate.gov/news-features/climate-qa/whats-hottest-earths-ever-been
