Read More: ScienceAlert
It's no secret that Siberia's permafrost has been on thin ice lately. Conditions are varying so much that huge holes are appearing out of nowhere, and, in some places, tundra is quite literally bubbling underneath people's feet. But new research has revealed that one of the biggest craters in the region, known by the local Yakutian people as the 'doorway to the underworld', is growing so rapidly that it's uncovering long-buried forests, carcasses, and up to 200,000 years of historical climate records. Known as the Batagaika crater, it's what's officially called a 'megaslump' or 'thermokarst'. Many of these megaslumps have been appearing across Siberia in recent years, but researchers think Batagaika could be something of an anomaly in the region, located around 660 km (410 miles) north-east of the region's capital city of Yakutsk. Not only is the crater already the largest of its kind, almost 1 km (0.6 miles) long and 86 metres (282 feet) deep, but it's getting bigger all the time.