Authors– Shuchita Srivastava, Yogesh Kant and D. Mitra

The Hayli Gubbi volcano in Ethiopia experienced its first confirmed eruption in approximately 12,000 years on 23 November 2025 at 14:00 IST, producing an ash column that reached an estimated altitude of 10–15 kilometers. The resulting plume was transported by upper-tropospheric winds toward India and China. Traveling at speeds of 100–120 km/h at altitudes between 5–13 km, the plume entered the western boundary of India on 24 November 2025 at 17:50 IST and cleared Indian skies by 25 November 2025 at 22:30 IST. Such plumes are capable of travelling thousands of kilometers with minimal dilution, allowing volcanic emissions to influence atmospheric composition far from the eruption source.

Volcanic plumes are major natural sources of sulfur dioxide (SO₂) and mineral ash, and their emissions can significantly modify the chemical and radiative properties of the upper troposphere and lower stratosphere (Carn et al., 2016; Textor et al., 2004). During long-range transport, volcanic SO₂ and ash often remain aloft for several days, enabling satellite instruments to track plume evolution and dispersal patterns with high confidence (Theys et al., 2019). TROPOMI satellite observations detected elevated SO₂ concentrations and high Aerosol Index (AI) values during the Hayli Gubbi volcanic plume’s passage over India.

Figure 1– Sulphur dioxide (mol/m²) plume over India due to Hayli Gubbi volcanic eruption in Ethiopia.

Figure 1 and Figure 2 show spatial distribution of TROPOMI SO₂ column density and absorbing aerosol index over the study region to highlight the location of volcanic plume during November 23 to November 26, 2025. Immediately after the eruption, TROPOMI detected elevated SO₂ columns concentrated near the vent, indicating strong degassing and injection of volcanic gases into the mid- to upper troposphere.

Figure 2. Variation of UV aerosol index over India due to Hayli Gubbi volcanic plume

On November 24, the SO₂ plume became elongated and drifted eastward, guided by prevailing upper-level winds, with significant concentrations observed over the Arabian Peninsula, and later extending toward Pakistan and Northern India. The AI panels show a similar evolution, capturing the movement of UV-absorbing volcanic ash along the same transport pathway. The spatial agreement between SO₂ and AI patterns confirms simultaneous transport of volcanic gases and aerosols, highlighting the eruption’s capacity to influence atmospheric composition across continental scales within a few days. These observations provided valuable information on the plume’s extent, intensity, and trajectory across the Indian region.

References

Carn, S.A., Clarisse, L., Prata, A.J., 2016. Multi-decadal satellite measurements of global volcanic degassing. Atmospheric Chemistry and Physics 16, 11477–11499.

Textor, C., Graf, H.F., Herzog, M., Oberhuber, J.M., 2004. Injection of gases into the stratosphere by explosive volcanic eruptions. Journal of Geophysical Research: Solid Earth 109, B06211.

Theys, N., et al., 2019. Volcanic SO₂ fluxes derived from TROPOMI. Geophysical Research Letters 46, 1061–1069.