Emergence of the Southeast Asian islands as a driver for Neogene cooling

Significance The Southeast Asian islands are a modern-day hotspot of CO 2 consumption via silicate weathering. Since ∼15 million years ago, these islands have been increasing in size at the same time that Earth’s climate has been cooling. Here, we test the hypothesis that this global cooling could have been driven by tectonic emergence of the Southeast Asian islands. Using a compilation of paleoshorelines, in conjunction with a coupled silicate weathering and climate model, we find that this emergence is associated with a large decrease in p CO 2 . Without these changes in tropical island paleogeography, there would not have been large Northern Hemisphere ice sheets as a defining feature of Earth’s climate over the past 3 million years.