"The past 17 years have seen some unusual rises in levels of methane gas in Earth’s atmosphere – and this surge might be a messenger for something bigger, according to new research. It’s not certain what this methane increase means exactly, but scientists argue it’s reminiscent of past “termination events" in Earth’s climate system that have ended ice ages."
https://www.iflscience.com/surging-methane-suggests-earth-is-brewing-an-ice-age-termination-event-71039
"Since 2006, the amount of heat-trapping methane in Earth’s atmosphere has been rising fast and, unlike the rise in carbon dioxide (CO₂), methane’s recent increase seems to be driven by biological emissions, not the burning of fossil fuels. This might just be ordinary variability – a result of natural climate cycles such as El Niño. Or it may signal that a great transition in Earth’s climate has begun.
Molecule for molecule, methane is a much more potent greenhouse gas than CO₂ but it lasts slightly less than a decade in the atmosphere compared with centuries for CO₂. Methane emissions threaten humanity’s ability to limit warming to relatively safe levels. Even more troubling, the rate at which methane is increasing in the atmosphere has accelerated recently. Something like this has happened before: sudden surges in methane marked the transitions from cold ice ages to warm interglacial climates."
https://theconversation.com/rising-methane-could-be-a-sign-that-earths-climate-is-part-way-through-a-termination-level-transition-211211