Plate tectonics, carbon, and climate

An updated view on the Urey cycle. Over the past 541 million years (the Phanerozoic eon), Earth’s climate has been relatively stable compared to preceding eons. However, there have been periods of longer glaciations, which have been attributed to changes in the balance between CO2 sources and sinks..

By Jens Hartmann

Apr 12th, 2019

Arc-continent collisions in the tropics set Earth’s climate state

On million-year time scales, Earth’s climate state is determined by sources and sinks of carbon to the ocean-atmosphere system. But which specific mechanisms are important in controlling the timing of glacial intervals? Macdonald et al. identify arc-continent collisions in the tropics as a primary control (see the Perspective by Hartmann). They compiled a database of Phanerozoic arc-continent collisions and the latitudinal distribution of ice sheets, showing that ice coverage was greatest when those collisions were most widespread, maximizing global weatherability.

By Francis A. Macdonald, et al.

Apr 12th, 2019