The carbon cycle, the process through which carbon moves between rocks, oceans, living organisms and the atmosphere, acts as Earth’s natural thermostat, regulating its temperature over long time periods.
The carbon cycle, the process through which carbon moves between rocks, oceans, living organisms and the atmosphere, acts as Earth’s natural thermostat, regulating its temperature over long time periods.
In a new study, published in the journal Nature, researchers looked at samples from rocks spanning the last three billion years and found evidence of a dramatic change in how this cycle functioned about 400 million years ago, when plants started to colonise land.
Specifically, the researchers noted a change in the chemistry of seawater recorded in the rock that indicates a major shift in the global formation of clay – the “clay mineral factory” – from the oceans to the land.
Since clay forming in the ocean (reverse weathering) leads to carbon dioxide being released into the atmosphere, while clay on land is a byproduct of chemical weathering that removes carbon dioxide from the air, this reduced the amount of carbon in the atmosphere, leading to a cooler planet and a seesawing climate, with alternating ice ages and warmer periods.
Read more at: University College London
Water collects on mosses. The first land plants were thought to be non-vascular, like mosses. (Photo Credit: Katmai Preserve NPS Photo/Russ Taylor)
