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Abstract Geyser and volcano monitoring suffer from temporal, geographic, and instrumental biases. We present a recording bias identified through multiyear monitoring of Steamboat Geyser in Yellowstone National Park, USA. Eruptions of Steamboat are the tallest of any geyser in the world and they produce broadband signals at two nearby stations in the Yellowstone National Park Seismograph Network. In winter, we observe lower eruption signal amplitudes at these seismometers. Instead of a source effect, we find that environmental conditions affect the recorded signals. Lower amplitudes for 23–45 Hz frequencies are correlated with greater snow depths at the station 340 m away from Steamboat, and we calculate an energy attenuation coefficient of 0.21 ± 0.01 dB per cm of snow. More long‐term monitoring is needed at geysers to track changes over time and identify recording biases that may be missed during short, sporadic studies. 

Abstract In the past century, most eruptions of Steamboat Geyser in Yellowstone National Park's Norris Geyser Basin were mainly clustered in three episodes: 1961–1969, 1982–1984, and ongoing since 2018. These eruptive episodes resulted in extensive disturbance to surrounding trees. To characterize tree response over time as an indicator of geyser activity adjustments to climate variability, aerial and ground images were analyzed to document changes in tree coverage around the geyser since 1954. Radiocarbon dating of silicified tree remnants from within 14 m of the geyser vent was used to examine geyser response to possible variations in decadal to centennial precipitation patterns. We searched for atypical or absent growth rings in cores from live trees in years associated with large geyser eruptions. Photographs indicate that active eruptive phases have adversely affected trees up to 30 m from the vent, primarily in the dominant downwind direction. Radiocarbon dates indicate that the geyser formed before 1878, in contrast to the birthdate reported in historical documents. Further, the ages of the silicified trees cluster within three episodes that are temporally correlated with periods of relative drought in the Yellowstone region during the 15th–17th centuries. The discontinuous growth of trees around the geyser suggests that changes in eruptive patterns occur in response to decadal to multidecadal droughts. This inference is supported by the lack of silicified specimens with more than 20 annual rings and by the existence of atypical or missing rings in live trees during periods of extended geyser activity. 

Abstract Doublet Pool is an active hydrothermal feature in Yellowstone National Park, USA. Approximately every half hour, it thumps for about 10 min due to bubbles collapsing at the base of the pool. To understand its thermodynamics and sensitivity to external factors, we performed a recurring multiple‐year passive seismic experiment. By linking recorded hydrothermal tremor with active thumping, we determine the onset and end of thumping, and the duration of silence between each thumping cycle. The silence interval decreased from around 30 min before November 2016 to around 13 min in September 2018. This change followed unusual thermal activity on the surrounding Geyser Hill. On a shorter time scale, wind‐driven evaporative cooling can lengthen the pre‐thumping silence interval. Based on energy conservation, we determine the heating rate and heat needed to initiate thumping to be 3–7 MW and ∼6 GJ, respectively. 

When and why earthquakes trigger volcano and geyser eruptions remains unclear. In September 2022, Steamboat Geyser in Yellowstone, USA erupted 8.25 hours after a local M3.9 earthquake—an improbable coincidence based on the geyser’s eruption intervals. We leverage monitoring data from the surrounding geyser basin to determine if the earthquake triggered this eruption. We calculate a peak ground velocity of 1.2 cm s−1, which is the largest ground motion in the area since Steamboat reactivated in March 2018 and exceeds a threshold associated with past earthquake-triggered geyser eruptions in Yellowstone. Despite no changes in other surface hydrothermal activity, we found abrupt, short-lived shifts in ambient seismic noise amplitude and relative seismic velocity in narrow frequency bands related to the subsurface hydrothermal system. Our analysis indicates that Steamboat’s eruption was likely earthquake-triggered. The hours-long delay suggests that dynamic strains from seismic waves altered subsurface permeability and flow which enabled eruption. 

Large gas bubbles can reach the surface of pools of mud and lava where they burst, often through the formation and expansion of circular holes. Bursting bubbles release volatiles and generate spatter, and hence play a key role in volcanic degassing and volcanic edifice construction. Here, we study the ascent and rupture of bubbles using a combination of field observations at Pâclele Mici (Romania), laboratory experiments with mud from the Imperial Valley (California, USA), numerical simulations and theoretical models. Numerical simulations predict that bubbles ascend through the mud as elliptical caps that develop a dimple at the apex as they impinge on the free surface. We documented the rupture of bubbles in nature and under laboratory conditions using high-speed video. The bursting of mud bubbles starts with the nucleation of multiple holes, which form at a near-constant rate and in quick succession. The quasi-circular holes rapidly grow and coalesce, and the sheet evolves towards a filamentous structure that finally falls back into the mud pool, sometimes breaking up into droplets. The rate of expansion of holes in the sheet can be explained by a generalization of the Taylor–Culick theory, which is shown to hold independent of the fluid rheology. 

Aside from captivating our senses, geysers have much to tell us about subsurface fluids, climate change effects, and the occurrence and limits of life on Earth and elsewhere in the solar system.