WASHINGTON (AP) — Even the dirt on the ground is making climate change worse, a new study finds.

Plants capture massive amounts of carbon, pumping it into the soil where usually it stays for hundreds or thousands of years.

Observations from across the globe show that as temperatures have warmed, bacteria and fungi in the soil are becoming more active. These turbo-charged microbes are feeding on dead leaves and plants, releasing more heat-trapping carbon dioxide into the air, according to a study in Wednesday's journal Nature .

Scientists call it a vicious cycle of warming. Burning of coal, oil...