During the 20th century there’s been an unprecedented, dramatic increase in wildfires in tropical peatlands. They store vast quantities of carbon below the Earth’s surface–more than all the world’s forest biomass combined. When they catch fire large amounts of the stored carbon is released into the atmosphere.
news.exeter.ac.uk/faculty-of-environment-science-and-economy/unprecedented-wildfires-in-tropical-peatlands-during-20th-century/