2026-10-14T14:55:24Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34056480 2026-10-02T12:03:31Z category_34 portal_316 item_type_3 month_year_10_2026

Data Sheet 1_Modulation of quasi-biennial oscillation by volcanic sulfate aerosols.pdf Prashant Chavan (12340177) Suvarna Fadnavis (11660722) Anton Laakso (22836572) Jean-Paul Vernier (25302219) Simone Tilmes (6869847) Chandran P. R. Satheesh (25302222) Vijay Sagar (25302225) Rolf Müller (11963) Environmental Science quasi-biennial oscillation (QBO) radiative forcing stratospheric heating sulfate aerosols volcanoes <p>Large and moderate volcanic eruptions significantly impact the stratosphere by releasing sulfur dioxide, thereby affecting atmospheric dynamics. Mt. Pinatubo erupted in 1991 and induced a warming of 3 K in the stratosphere that led to prolonged easterly wind regimes of the Quasi-biennial oscillation (QBO). Using a three-member ensemble mean obtained from the ECHAM6-HAMMOZ model, we show the impact of eruptive volcanoes on the tropical stratosphere and the QBO from 2003 to 2013. Our simulations with volcanoes, when compared to simulations without volcanoes, show that volcanic sulfate aerosols enhanced the stratospheric aerosol optical depth (SAOD) 2 months after the eruptions of Rabaul (0.0024 ± 0.0018), Sarychev (0.0058 ± 0.0031), and Nabro (0.0075 ± 0.0053). 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> 2026-10-02T12:03:31Z Dataset Dataset 10.3389/fenvs.2026.1831183.s001 https://figshare.com/articles/dataset/Data_Sheet_1_Modulation_of_quasi-biennial_oscillation_by_volcanic_sulfate_aerosols_pdf/34056480 CC BY 4.0