Krakatoa, Tonga, Chelyabinsk: the sound that circled the Earth

Library → Great events

Some catastrophes are so vast that instruments can "hear" them on the other side of the planet. These cases became turning points for the science of infrasound — and proved that air can carry sound all the way around the globe.

Krakatoa, 1883 — the birth of a science

On 27 August 1883 the Indonesian volcano Krakatoa exploded with a force that is hard to imagine. 160 km away, at a gasworks in Batavia, a barometer recorded a pressure spike equivalent to more than 170 decibels — possibly the loudest sound in documented history.3

But something else is more astonishing: the air wave circled the globe several times. The barographs of more than 50 weather stations around the world recorded its passage roughly every 34 hours over several days.3 The Royal Society of London gathered this data into the famous report of the Krakatoa Committee (1888) — effectively the first global study of infrasound.1 2

A detail

The sound of the explosion itself was heard by people 4,800 km away — including on Rodrigues Island in the Indian Ocean, where it was mistaken for distant cannon fire. This is probably the record for the range of audible sound in history.

Hunga Tonga, 2022 — a repeat 140 years later

On 15 January 2022 the underwater volcano Hunga Tonga–Hunga Haʻapai exploded so powerfully that it produced a Lamb atmospheric wave that circled the planet several times. This time it was recorded not by a handful of barographs, but by a global network of precise instruments and thousands of amateur pressure sensors. The event became the most studied infrasound phenomenon in history and confirmed that even simple barometers catch a planetary-scale wave.4

Chelyabinsk, 2013 — a voice from space

On 15 February 2013 a meteor exploded over Chelyabinsk. The shock wave shattered windows in thousands of buildings — and its infrasound became the largest signal ever recorded by the infrasound network of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO). The wave was caught by stations around the world, some after it had gone around the planet.5 It was from such infrasound records that scientists learned to estimate the energy of incoming cosmic bodies in TNT equivalent — a working tool of planetary defence.6

Did you know?

The Krakatoa air wave went around the globe several times — barographs caught its "ticking" for almost five days.
The pressure spike from Tonga 2022 was noticed by home weather stations in Europe — almost 17,000 km from the volcano.
The Chelyabinsk bolide produced infrasound more powerful than any the CTBTO network had recorded in its entire history of observation.

Why this matters for HERD

Tonga 2022 is our direct proof of concept: a planetary event's wave was recorded even by household barometers. That means a dense network of cheap sensors can catch large events — we just need to bring it up to the level of reliable early warning.

Sources for this article

These sources are part of the full HERD library — 272 vetted sources, with meaning search and topic filters.

history Symons G.J. (ed.) (1888). The Eruption of Krakatoa, and Subsequent Phenomena. Royal Society Krakatoa Committee. archive.org
reviewhistory Gabrielson T.B. (2004). Krakatoa and the Royal Society. Acoustics Today / ECHOES. acousticstoday.org
pop-sci Cox A. (2014). The Sound So Loud That It Circled the Earth Four Times. Nautilus. nautil.us
peer-reviewed Matoza R.S. et al. (2022). Global seismoacoustic observations of the January 2022 Hunga eruption, Tonga. Science 377. science.org
peer-reviewed Le Pichon A. et al. (2013). The 2013 Russian fireball largest ever detected by CTBTO infrasound sensors. GRL 40. agupubs.wiley.com
peer-reviewed Edwards W.N., Brown P.G., ReVelle D.O. (2006). Estimates of meteoroid kinetic energies from observations of infrasonic airwaves. J. Atmos. Sol.-Terr. Phys. 68. doi.org
peer-reviewed Wright C.J. et al. (2022). Surface-to-space atmospheric waves from Hunga Tonga-Hunga Ha'apai eruption. Nature 609. doi.org
peer-reviewed Vergoz J. et al. (2022). IMS observations of infrasound and acoustic-gravity waves produced by the January 2022 volcanic eruption of Hunga, Tonga: A global analysis. Earth and Planetary Science Letters 591. doi.org
peer-reviewed Amores A. et al. (2022). Numerical Simulation of Atmospheric Lamb Waves Generated by the 2022 Hunga-Tonga Volcanic Eruption. Geophysical Research Letters 49(6). doi.org
peer-reviewed Themens D.R. et al. (2022). Global Propagation of Ionospheric Disturbances Associated With the 2022 Tonga Volcanic Eruption. Geophysical Research Letters 49(7). doi.org
review Yuen D.A. et al. (2022). Under the surface: Pressure-induced planetary-scale waves, volcanic lightning, and gaseous clouds caused by the submarine eruption of Hunga Tonga-Hunga Ha'apai volcano. Earthquake Research Advances 2(3). doi.org
peer-reviewed Brown P.G. et al. (2013). A 500-kiloton airburst over Chelyabinsk and an enhanced hazard from small impactors. Nature 503. doi.org
peer-reviewed Popova O.P. et al. (2013). Chelyabinsk Airburst, Damage Assessment, Meteorite Recovery, and Characterization. Science 342(6162). doi.org
history Whipple F.J.W. (1934). On phenomena related to the great Siberian meteor. Quarterly Journal of the Royal Meteorological Society 60(257). doi.org
history Ben-Menahem A. (1975). Source parameters of the Siberian explosion of June 30, 1908, from analysis and synthesis of seismic signals. Physics of the Earth and Planetary Interiors 11(1). doi.org
organization Silber E.A., Whitaker R.W. (2025). Historical Bolide Infrasound Dataset (1960-1972). Data 10(5):71 (MDPI). doi.org