CH₄ data from the Halogen Occultation Experiment show clear changes in the deep and shallow branches of the Brewer–Dobson circulation (BDC) from 1992 to 2005. CH₄ decreased in the upper stratosphere in the early 1990s following the Pinatubo eruption. There was also meridional transport of CH₄ from the tropics to mid-latitudes in both hemispheres in the late 1990s. CH₄ trends in the shallow branch agree with the tropospheric CH₄ trends from 1996 to 2005.