Geological data prove that Earth’s climate has remained continuously habitable for more than 3 billion years. However, it has been precariously balanced, with the potential to rapidly deteriorate to deep-frozen or intolerably hot conditions, causing planet-wide sterility.
Now Professor Toby Tyrrell, a specialist in Earth System Science at Southampton, has used the University’s Iridis supercomputing facility to run simulations looking at how 100,000 randomly different planets responded to random climate-altering events spread out across 3 billion years, until they reached a point where they lost their habitability.
The study results suggest that chance is a major factor in influencing whether planets, such as Earth, can continue to nurture life over billions of years.
We can now understand that Earth stayed suitable for life for so long due, at least in part, to luck. For instance, if a slightly larger asteroid had hit Earth, or had done so at a different time, then Earth may have lost its habitability altogether.
Toby Tyrrell - Professor of Earth System Science