Earth’s Climate May Be Undergoing a ‘Termination-Level Transition’ as Methane Rises

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.