Researchers say Earth’s core may be cooling ‘more rapidly than expected’

Researchers are warning that the Earth‘s core may be cooling “more rapidly than expected,” which could speed up the timeline for when the planet becomes uninhabitable for humans.

In a paper published in the journal Earth and Planetary Science Letters, a group of researchers reported that the Earth’s mantle is “much more efficiently cooled, which would ultimately weaken many tectonic activities driven by the mantle convection more rapidly than expected from conventionally believed thermal conduction behavior.”

The researchers noted that the rate at which the Earth has been losing heat “directly links to the fundamental question on how long the Earth will remain dynamically active.”

Earth has been cooling throughout its 4.5 billion year history, according to the researchers, but the rate at which temperatures have been dropping is still being scrutinized, NBC News noted.

The researchers examined bridgmanite, a conductive mineral that can be located between the core and the mantle of Earth, according to NBC News. The team wrote in the paper that the mineral is 1.5 times more conductive than it was thought to be, which suggests the planet may be cooling at a quicker rate than previously believed.

“We found the bulk thermal conductivity at core-mantle boundary becomes ∼1.5 times higher than the conventionally assumed value, which supports higher heat flow from core, hence more vigorous mantle convection than expected,” the researchers wrote.

When the planet gets cold enough, it will begin losing its magnetic field, which protects the Earth from damaging cosmic radiation. This would ultimately lead the planet to become sterile and unlivable. The research team did not, however, provide an estimate as to how many more years life can be sustained on Earth.

Andrew Rushby of the University of East Anglia in the United Kingdom forecasted in 2013 that the Earth could remain habitable for between 1.75 billion and 3.25 billion more years, according to NBC News, as long as the planet does not experience a nuclear holocaust, rogue asteroid or a different unexpected catastrophe.