Data Sheet 1_Modulation of quasi-biennial oscillation by volcanic sulfate aerosols.pdf

The increase in mean tropical SAOD over the study period 2003–2013, driven by several volcanic eruptions, produced an average radiative forcing of −0.45 ± 0.21 W m^-2 at the top of the atmosphere (TOA) and −0.47 ± 0.26 W m^-2 at the surface in the tropical region. Volcanic aerosol precursors are injected into the tropical stratosphere through volcanic plumes, leading to an increase in sulfate aerosol concentrations of 59.6 ± 11.1 ng m^-3 and heating rates of 0.05 ± 0.02 × 10⁻² K d^-1 in the tropical lower stratosphere.

The model simulations show that stratospheric heating caused by the volcanoes disrupts the QBO phases, resulting in the reversal of the easterly to westerly phase and vice versa. Our study shows that moderate and large volcanoes modulate the QBO.</p>