Volcanoes and wildfires contributed to increased stratospheric humidification

Observations from satellites and climate-model simulations show that moderate volcanic eruptions and extreme wildfires have humidified the stratosphere since 2005. The aerosol-mediated effects of these eruptions and fires explain about one-third of the observed stratospheric water-vapour trend, a contribution similar to that of surface warming. Moderate eruptions and extreme fires account for about one-third of the upward trend in stratospheric moisture.