Magnetic storms induce geoelectric fields at Earth's surface that can interfere with grounded long-line systems. The September 1859 storm disrupted global telegraph operations, the March 1989 storm caused a blackout in Canada and interfered with electric-power-transmission systems in the United States, and other storms have had related impacts. The geographic and temporal dependence of geoelectric fields are functions of both geomagnetic variation and local surface impedance, which differ considerably across different geological regions. These dependencies can be mapped across the contiguous United States by combining magnetotelluric impedance tensors with ground magnetometer time series. This review illustrates such mapping for the 1989 storm and shows that power-system interference was experienced where surface impedance is high, and when and where geoelectric fields were intense. Statistical analyses indicate that storms comparable to that of March 1989 occur roughly once every four solar cycles. Ongoing developments in numerical modeling and real-time monitoring are anticipated to enable prediction of geoelectric hazards. ▪ Magnetic storms can induced electric fields in the solid Earth that interfere with electric-power-transmission systems. ▪ Geoelectric hazards depend on the storm-time geomagnetic disturbance and the electrical conductivity structure of Earth. ▪ Historically, impacts on telecommunication and power-transmission systems in the United States have been concentrated in the East and Midwest. ▪ The future occurrence of a magnetic superstorm could cause widespread disruption of electric-power-transmission systems.

The geological record provides us with absolute ages of past events and organisms, but it also contains information about what occurred within time intervals ranging from seconds to eons. Within this huge range of time samples, intervals that span days to tens of thousands of years can be the hardest to calibrate in convincing ways, yet knowing how much time is recorded in fossil samples is essential for reconstructing terrestrial and marine paleoecology. A career of field research in sedimentology, stratigraphy, paleontology, observations and experiments in modern land ecosystems (neo-taphonomy), and comparisons of fossil preservation across the Phanerozoic record has convinced me that we can make credible estimates of time intervals represented by different types of fossil assemblages. The examples in this autobiographical review trace the development of my understanding of time-averaging in the fossil record and suggest how future research can unlock new information about ancient ecosystems and their inhabitants.

The Double Asteroid Redirection Test (DART) was NASA's first planetary defense test mission, designed to validate the technologies and methods associated with using a kinetic impactor to deflect asteroids that pose a threat to Earth. On September 26, 2022, DART intentionally collided with Dimorphos, the moonlet of the near-Earth asteroid Didymos. Observations over the following weeks and months confirmed that DART's impact changed Dimorphos's orbit around Didymos, reducing its speed by 2.6 mm $/$ s. In addition, the DART impact provided the opportunity to observe the creation and evolution of the resulting ejecta, to investigate the dynamics within a perturbed binary system, and to study a natural-scale asteroid impact experiment. Additionally, the Didymos-Dimorphos system was the first binary near-Earth asteroid system investigated by spacecraft, and Dimorphos is the smallest asteroid visited by spacecraft to date. We detail the science and planetary defense findings of DART and look to future advancements. ▪ NASA's Double Asteroid Redirection Test (DART) mission was the first to demonstrate asteroid deflection, autonomously navigating to impact the asteroid Dimorphos on September 26, 2022. ▪ DART's successful planetary defense test validated that the kinetic impactor (KI) technique is a viable means to alter an asteroid's future path, which could potentially be used to prevent a future Earth impact. ▪ Analysis of the DART impact event and the resulting aftermath showed that the efficiency of the deflection achieved by the KI technique depended on the asteroid's properties. ▪ Prior information about the asteroid and its properties, such as by a reconnaissance mission, has the potential to allow optimization of the KI technique for asteroid deflection. ▪ Warning time is key for utilizing the KI technique to prevent a potential Earth impact, stressing the need for a planetary defense strategy that includes searching for asteroids and characterizing them in addition to developing mitigation approaches. ▪ In addition to advancing planetary defense objectives, the DART mission provided the first close-up visit to a binary asteroid system and measurements on the smallest asteroid visited by a spacecraft to date. ▪ The success of the DART mission relied on an interdisciplinary and international team, demonstrating the value of wide-ranging cooperation for planetary defense efforts.

Understanding the composition of metallic cores in planetary bodies is crucial for unraveling planetary formation, differentiation, and evolution. On Earth, early seismic and density data suggested iron-dominated interiors alloyed with lighter elements such as sulfur, silicon, oxygen, carbon, hydrogen, and nitrogen. These elements influence core density, thermal conductivity, magnetic field generation, and surface habitability, and their incorporation depends on each planet's unique pressure, temperature, and redox conditions during differentiation. Experimental investigations of metal-silicate partitioning under extreme conditions show that many light elements are strongly siderophile at high pressures, contributing to the diversity of core compositions across the Solar System and beyond. This review synthesizes current knowledge on core compositions beyond Earth—spanning asteroids to exoplanets—and explores how laboratory experiments, cosmochemical evidence, and astrophysical observations collectivelyinform our understanding of core formation. By decoding core compositions, studies can better constrain the thermal histories and potential habitability of planetary bodies. ▪ Planetary core compositions reveal how planets form, differentiate, and evolve, shaping the density, heat flow, magnetic fields, and habitability of a planet. ▪ Experiments, cosmochemical abundances, and theoretical calculations explain the light element compositions of planetary cores from asteroids to exoplanets.

The Black Sea, characterized by its unique oceanographic and biogeochemical gradients and oxygen-depleted (anoxic) waters, serves as a natural analogue of past planetary-scale geological events as well as more recent human-induced changes. In this review, based on a synthesis of the most recent research, we demonstrate how the extreme ecosystems of the Black Sea provide valuable insights into ecological resilience and adaptation in a changing global ocean. We also elaborate on how the Black Sea's biogeochemical oceanographic extremities parallel conditions found in some of the most extreme environments of our planet as well as newly discovered oceans of the Solar System, offering a crucial analogue for astrobiological and extreme environment research. As such, the Black Sea holds significant relevance not only for understanding Earth's past oceans and present ecological dynamics but also for advancing the exploration of life's potential beyond our planet. ▪ The Black Sea is shaped by oceanographic gradients with Earth's largest volume of oxygen-depleted and sulfide-rich waters. ▪ The habitats of the Black Sea host not only unique bacterial and archaeal lineages but also eukaryotic organisms adapted to extreme conditions. ▪ It is also an excellent laboratory environment to study the geological past of Earth's ocean and for future studies of the Solar System's ocean worlds. ▪ Managing the Black Sea's environmental challenges should be a priority as well to keep this unique natural laboratory stable and accessible for future generations.

Geoscience remains one of the least diverse science, technology, engineering, and mathematics disciplines, despite investment in diversity initiatives. Obstacles such as insufficient funding, paucity of geoscience offerings, and lack of information continue to promote a culture of exclusion. This review critically examines the evolution of belonging, accessibility, justice, equity, diversity, and inclusion (BAJEDI) programs in the geosciences, focusing on efforts to increase participation and retention of minoritized people of color. We explore the philosophical foundations that have shaped BAJEDI efforts and the challenges they face despite realistic gains. This review identifies institutional and political limitations and offers recommendations to support positive, long-term institutional and systemic change. We underscore the need to move beyond symbolic gestures and argue for ethic of care practices that center authentic, relational interactions and systemic accountability. Understanding what truly works and the conditions under which it works for minoritized people of color is critical to building a more inclusive and innovative geoscience community. ▪ Increasing racial diversity in geoscience requires sustained, resilient, and evidence-based strategies rather than short-term or ad hoc efforts. ▪ Efforts to increase racial diversity and improve the experiences of people of color in geoscience must attend to relational dynamics within the field. ▪ Learning from past missteps and evaluating what works are essential to strengthening existing efforts and advancing racial diversity in geoscience. ▪ Including an ethic of care, rather than relying primarily on deontological or utilitarian frameworks, within diversity programs and policies is key to meaningful, lasting transformation in geoscience.

Vertical land motion (VLM) is an underrecognized hazard in susceptible coastal cities, especially those experiencing rapid urbanization. Human-induced VLM often causes elevation loss (subsidence) at rates that exceed, sometimes by an order of magnitude or more, those of climate-driven sea-level rise. Local land subsidence (LLS) also damages infrastructure, disrupts drainage, and alters flood dynamics, yet its broader impacts remain poorly quantified and systematically assessed. This review synthesizes the scientific, technical, and policy dimensions of VLM, with particular focus on LLS, highlighting how natural processes and human activities interact to amplify coastal hazards. We examine the geophysical drivers of VLM, advances in monitoring and modeling, and their integration into hazard assessment frameworks. We consider socioeconomic and infrastructural vulnerabilities of city residents, especially where limited observational capacity and governance gaps intensify risk. VLM acts as both a physical amplifier and a socio-institutional blind spot within coastal adaptation planning, requiring real-time data integration, scenario testing, and inclusive policy development. Finally, we identify key research frontiers—including subsidence mitigation strategies, dynamic VLM projections, and equitable, high-resolution risk assessment—to support more resilient, adaptive, and just coastal futures. ▪ Tectonics, sediment compaction, groundwater extraction, and urban loading combine to produce complex, nonlinear patterns of vertical land motion that shape local hazard dynamics. ▪ Local land subsidence, often exceeding the rate of global sea-level rise, is the dominant and least understood driver of coastal flooding and infrastructure risk in many urban regions worldwide. ▪ Subsidence disproportionately affects marginalized communities, exacerbating social inequities, driving displacement, and eroding cultural heritage, underscoring the need for inclusive, justice-centered adaptation frameworks. ▪ Closing critical data and policy gaps through coordinated vertical land motion observation, open-access standards, and equitable governance is essential to safeguard coastal populations and sustain long-term urban resilience.

Volcanic eruptions exert a profound influence on tropical hydroclimate, including interannual variability associated with the El Niño–Southern Oscillation. This review synthesizes recent advances in understanding these impacts through an energy framework that links radiative forcing to shifts in the Intertropical Convergence Zone (ITCZ) and global monsoon systems. While global responses are robust in climate models, regional expressions remain uncertain due to biases and limitations in both simulations and paleoclimate reconstructions. Nonetheless, consistent patterns emerge—such as ITCZ displacement and reduced monsoon precipitation—that align with energetic theory, offering a physically grounded explanation for observed hydroclimatic anomalies following eruptions. This framework also provides a basis for estimating potential hydroclimate impacts of future volcanic events. ▪ Volcanic eruptions strongly influence tropical hydroclimate, but the mechanisms linking radiative forcing to large-scale responses are not fully understood. ▪ We assess evidence from climate models and paleoclimate reconstructions, noting robust global responses but regional differences due to model biases and data limitations. ▪ The energy framework provides a physically based foundation for anticipating tropical hydroclimate responses to future volcanic eruptions. ▪ Consistent patterns emerge such as ITCZ shifts and weakened monsoons, explained by energy theory and underpinned by observed posteruption climate anomalies.

Geoethics is an evolving interdisciplinary field that provides ethical guidance for how humanity interacts with the Earth system. Originating in professional geoscience ethics, it has expanded to include the ethical, social, and cultural aspects of geoscientific practice. Today, it is proposed as a foundation for developing a global ethics. This review traces the evolution of geoethics through key milestones, such as international organizations and foundational documents, and outlines its core principles. It also highlights the wide-ranging applicability of geoethics across diverse and pressing issues. The practical relevance of geoethics extends to fields such as disaster risk reduction, geo-resource management, the protection of geodiversity and geoheritage, geoeducation, and geoscience communication. Geoethics also provides ethical reflections in emerging and controversial domains, including deep-sea mining and the use of artificial intelligence in geosciences. By fostering ethical awareness, responsibility, and reflexivity in geoscientific practice, geoethics contributes to shaping a more sustainable, inclusive, and just future. ▪ Geoethics integrates geoscience, ethics, and society to guide responsible human-Earth interactions. ▪ It provides a framework for addressing global challenges such as climate change and resource management. ▪ Geoethics promotes scientific integrity, sustainability, and planetary stewardship across disciplines. ▪ Its principles foster ethical awareness, shaping policy, education, and societal engagement worldwide.

It is currently debated whether Earth system models (ESMs) can reproduce observation-based long-term changes in global and regional deoxygenation rates. Both models and observations include uncertainties, which must be considered when evaluating their consistency. Based on 14 ESMs and 6 observational datasets, the models’ climatological annual mean oxygen matches observations well near the surface. However, significant biases remain in the tropics and in the thermocline. Based on the same set of models and three time-varying observation-based datasets, the models tend to underestimate deoxygenation trends from 1965 to 2014, except for the North Atlantic basin. However, the small number of observational datasets limits this conclusion. One dataset appears to significantly underestimate deoxygenation due to sparse data coverage. This review highlights the need for improvements in model process representations and the development of more observation-based, quality-controlled datasets to better constrain and interpret oxygen changes in the ocean. ▪ Uncertainties of dissolved oxygen field in CMIP6 ESMs and observational reconstructions are quantified. ▪ The ESMs can skillfully reproduce long-term average oxygen near the surface, but challenges remain in the thermocline and tropics. ▪ The ESMs underestimates the deoxygenation trends except for the North Atlantic basin.