/ Milankovitch cycles Content for UC Davis en /blog/deep-water-sediments-reveal-patterns-extraterrestrial-influence-earths-ancient-climates <p><span lang="EN-US">Roughly 34 million years ago, the Earth started transitioning from a greenhouse to an icehouse state — defined by long-term cooling trends that resulted in ice sheets in the planet’s polar regions. During this time, continental carbon reservoirs expanded as carbon dioxide decreased in the atmosphere.</span></p><p><span lang="EN-US">But that trend has reversed. Fossil fuel consumption, among other sources of pollution, have resulted in increasing atmospheric and oceanic temperatures, leading to ice sheet melt and unprecedented shifts in our environments.&nbsp;</span></p> October 31, 2025 - 10:42am Andy Fell /blog/deep-water-sediments-reveal-patterns-extraterrestrial-influence-earths-ancient-climates