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A workplace climate survey conducted among geoscientists at the University of Hawai‘i at Mānoa, USA, was analyzed in two ways: Whole data set analysis (basic descriptive statistics were calculated for the set of responses to each climate survey item, without considering demographics) and demographic analysis (responses were examined through a demographic lens to identify any statistically significant correlations between respondents’ perceptions of climate and various aspects of their identities). The whole data set analysis revealed a strongly positive perception of the EARTH/HIGP (Department of Earth Sciences/Hawai‘i Institute of Geophysics and Planetology) workplace climate. A few areas that warrant further attention are presented at the end of the “Data and Results 1: Whole Data Set Analysis” section. The demographic analysis revealed statistically significant differences (p < 0.05) in perceptions of workplace climate. Of the 115 climate survey items examined, 78 (or 68%) showed significant differences within at least one demographic dimension. In other words, the workplace climate is perceived significantly differently by different demographic groups. Of the 18 demographic dimensions analyzed, all (100%) showed significant differences in at least one workplace climate survey item. For the vast majority of significant differences, the minoritized or marginalized groups had a more negative perception of workplace climate than the majority groups. The demographic dimension associated with the greatest number of significant differences (46) was “condition” (defined as “health conditions that impacted your learning, working or living activities in the past 12 months”). The responses of those who reported at least one condition indicated considerably greater disenfranchisement compared with those who reported no conditions. An intersectional demographic analysis was precluded due to the small sample size (n = 49), and we note this as a serious limitation. However, despite the small sample size, the fact that statistically significant results were found underscores the value of conducting climate surveys, even at a relatively small scale. 

This dataset archived with the Earthref Magnetics Information Consortium contains low-temperature remanent magnetization data generated at the Institute for Rock Magnetism, University of Minnesota. This dataset accompanies the publication McCartney, K., Hammer, J.E., Shea, T., Brachfeld, S., Giachetti, T., 2024. Investigating the role of nanoscale titanomagnetite in bubble nucleation via novel applications of magnetic analyses (Dataset), Magnetics Information Consortium (MagIC), doi:10.7288/V4/MAGIC/20019. 

This dataset archived with the Magnetics Information Consortium contains rock-magnetic data for rhyolitic pumice and obsidian from Glass Mountain, Medicine Lake, California, USA. Data were generated at Montclair State University and include magnetic susceptibility measured at 976Hz and 3904Hz, magnetic susceptibility vs. temperature, anhysteretic remanent magnetization (ARM), and magnetic hysteresis measurements. This dataset accompanies the publication Brachfeld, S., McCartney, K., Hammer, J.E., Shea, T., Giachetti, T., Evaluating the role of titanomagnetite in bubble nucleation: Rock magnetic detection and characterization of nanolites and ultra-nanolites in rhyolite pumice and obsidian from Glass Mountain, California, Geochemistry Geophysics Geosystems, https://doi.org/10.1029/2023GC011336. 

We document the presence, composition, and number density (TND) of titanomagnetite nanolites and ultra‐nanolites in aphyric rhyolitic pumice, obsidian, and vesicular obsidian from the 1060 CE Glass Mountain volcanic eruption of Medicine Lake Volcano, California, using magnetic methods. Curie temperatures indicate compositions of Fe2.40Ti0.60O4 to Fe3O4. Rock‐magnetic parameters sensitive to domain state, which is dependent on grain volume, indicate a range of particle sizes spanning superparamagnetic (<50–80 nm) to multidomain (>10 μm) particles. Cylindrical cores drilled from the centers of individual pumice clasts display anisotropy of magnetic susceptibility with prolate fabrics, with the highest degree of anisotropy coinciding with the highest vesicularity. Fabrics within a pumice clast require particle alignment within a fluid, and are interpreted to result from the upward transport of magma driven by vesiculation, ensuing bubble growth, and shearing in the conduit. Titanomagnetite number density (TND) is calculated from titanomagnetite volume fraction, which is determined from ferromagnetic susceptibility. TND estimates for monospecific assemblages of 1,000 nm–10 nm cubes predict 10^12 to 10^20 m^−3 of solid material, respectively. TND estimates derived using a power law distribution of grain sizes predict 10^18 to 10^19  m^−3. These ranges agree well with TND determinations of 10^18 to 10^20  m^−3 made by McCartney et al. (2024), and are several orders of magnitude larger than the number density of bubbles in these materials. These observations are consistent with the hypothesis that titanomagnetite crystals already existed in extremely high number‐abundance at the time of magma ascent and bubble nucleation. 

Nucleation of H2O vapor bubbles in magma requires surpassing a chemical supersaturation threshold via decompression. The threshold is minimized in the presence of a nucleation substrate (heterogeneous nucleation, <50 MPa), and maximized when no nucleation substrate is present (homogeneous nucleation, >100 MPa). The existence of explosively erupted aphyric rhyolite magma staged from shallow (<100 MPa) depths represents an apparent paradox that hints at the presence of a cryptic nucleation substrate. In a pair of studies focusing on Glass Mountain eruptive units from Medicine Lake, California, we characterize titanomagnetite nanolites and ultrananolites in pumice, obsidian, and vesicular obsidian (Brachfeld et al., 2024,https://doi.org/10.1029/2023GC011336), calculate titanomagnetite crystal number densities, and compare titanomagnetite abundance with the physical properties of pumice to evaluate hypotheses on the timing of titanomagnetite crystallization. Titanomagnetite crystals with grain sizes of approximately 3–33 nm are identified in pumice samples from the thermal unblocking of low‐temperature thermoremanent magnetization. The titanomagnetite number densities for pumice are 10^18 to 10^20 m^−3, comparable to number densities in pumice and obsidian obtained from room temperature methods (Brachfeld et al., 2024,https://doi.org/10.1029/2023GC011336'>https://doi.org/10.1029/2023GC011336). This range exceeds reported bubble number densities (BND) within the pumice from the same eruptive units (average BND ∼4 × 10^14 m^−3). The similar abundances of nm‐scale titanomagnetite crystals in the effusive and explosive products of the same eruption, together with the lack of correlation between pumice permeability and titanomagnetite content, are consistent with titanomagnetite formation having preceded the bubble formation. Results suggest sub‐micron titanomagnetite crystals are responsible for heterogeneous bubble nucleation in this nominally aphyric rhyolite magma. 

The science of volcanology advances disproportionately during exceptionally large or well-observed eruptions. The 2018 eruption of Kīlauea Volcano (Hawai‘i) was its most impactful in centuries, involving an outpouring of more than one cubic kilometer of basalt, a magnitude 7 flank earthquake, and the volcano's largest summit collapse since at least the nineteenth century. Eruptive activity was documented in detail, yielding new insights into large caldera-rift eruptions; the geometry of a shallow magma storage-transport system and its interaction with rift zone tectonics; mechanisms of basaltic tephra-producing explosions; caldera collapse mechanics; and the dynamics of fissure eruptions and high-volume lava flows. Insights are broadly applicable to a range of volcanic systems and should reduce risk from future eruptions. Multidisciplinary collaboration will be required to fully leverage the diversity of monitoring data to address many of the most important outstanding questions. ▪ Unprecedented observations of a caldera collapse and coupled rift zone eruption yield new opportunities for advancing volcano science. ▪ Magma flow to a low-elevation rift zone vent triggered quasi-periodic step-like collapse of a summit caldera, which pressurized the magma system and sustained the eruption. ▪ Kīlauea's magmatic-tectonic system is tightly interconnected over tens of kilometers, with complex feedback mechanisms and interrelated hazards over widely varying time scales. ▪ The eruption revealed magma stored in diverse locations, volumes, and compositions, not only beneath the summit but also within the volcano's most active rift zone. Expected final online publication date for the Annual Review of Earth and Planetary Sciences, Volume 52 is May 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.