The Tonga volcano eruption at 04:14:45 UT on 2022-01-15 released enormous amounts of energy into the atmosphere, triggering very significant geophysical variations not only in the immediate proximity of the epicenter but also globally across the whole atmosphere. This study provides a global picture of ionospheric disturbances over an extended period for at least four days. We find traveling ionospheric disturbances (TIDs) radially outbound and inbound along entire Great-Circle loci at primary speeds of ~300-350 m/s (depending on the propagation direction) and 500-1000 km horizontal wavelength for front shocks, going around the globe for three times, passing six times over the continental US in 100 hours since the eruption. TIDs following the shock fronts developed for ~8 hours with 10-30 min predominant periods in near- and far- fields. TID global propagation is consistent with the effect of Lamb waves which travel at the speed of sound. Although these oscillations are often confined to the troposphere, Lamb wave energy is known to leak into the thermosphere through channels of atmospheric resonance at acoustic and gravity wave frequencies, carrying substantial wave amplitudes at high altitudes. Prevailing Lamb waves have been reported in the literature as atmospheric responses to the gigantic Krakatoa eruption in 1883 and other geohazards. This study provides substantial first evidence of their long-duration imprints up in the global ionosphere. This study was enabled by ionospheric measurements from 5,000+ world-wide Global Navigation Satellite System (GNSS) ground receivers, demonstrating the broad implication of the ionosphere measurement as a sensitive detector for atmospheric waves and geophysical disturbances.

Machine learning has led to improvements in the efficiency and efficacy of subsurface engineering and characterization efforts that benefits the hydrocarbon and geothermal exploration and production as well as in carbon geo-sequestration. There have been rapid increases in sensor deployment, data acquisition, data storage, and data processing for purposes of geothermal/fossil energy development and exploration along with carbon geo-sequestration. This has promoted large-scale development of data-driven methods, machine learning and data analytics workflows to find and extract energy and material resources from the subsurface earth. Subsurface data ranges from nano-scale to kilometer-scale passive as well as active measurements in the form of physical fluid/solid samples, images, 3D scans, time-series data, waveforms, and depth-based multi-modal signals representing various physical phenomena, ranging from transport, chemical, mechanical, electrical, and thermal properties, to name a few. Integration of such varied multimodal, multipoint, time-varying data sources being acquired at varying scales, rates, resolutions, and volumes mandates robust machine learning methods to better characterize and engineer the subsurface earth. This review paper lays out popular machine learning applications in exploration, extraction, and recovery of subsurface energy resources, primarily in hydrocarbon exploration and production industry with potential applications in geothermal energy production and carbon geo-sequestration.

Earth system models (ESMs) and mesoscale models have come to employ increasingly complex parameterization schemes for the atmospheric boundary layer (ABL), requiring surface boundary conditions for numerous higher order turbulence statistics. Of particular interest is the potential temperature variance (PTV), which is used not only as a boundary condition itself but also to close boundary conditions of other statistics. The existing schemes in ESMs largely rely on the assumptions of Monin-Obukhov similarity theory (MOST), and are not necessarily applicable over complex and heterogeneous surfaces where large scale circulations and roughness sub-layer effects may cause deviations from MOST. The National Ecological Network (NEON) is used here to evaluate existing parameterizations for the surface boundary of PTV, note key deficiencies, and explore possible remedies. The results indicate that existing schemes are acceptable over a variety of surface conditions provided the analysis of a priori filters out low frequency variability not associated with turbulent time scales. There was, however, significant inter-site variability in observed similarity constants and a significant bias when compared to the textbook values of these parameters. Existing models displayed the poorest performance over heterogeneous sites, and rough landscapes. Attempts to use canopy structure and surface roughness characteristics to improve the results confirmed a relation between these variables and PTV, but failed to significantly improve the predictive power of the models. The results did not find strong evidence indicating that large scale circulations caused substantial deviations from textbook models, although additional analysis is required to assess their full impacts.

South Turkish Neogene basins record post-collisional exhumation/erosion of Neotethyan basins. Facies and paleocurrent data indicate general northerly derivation of siliciclastic sediments. Provenance is further indicated by integrated detrital zircon U-Pb geochronology (29 samples; 2748 grains) of 7 mapped late Oligocene-Miocene basins (from E-W): 1. Hatay, 2. K.Maraş, 3. Adana, 4. Misis, 5. Mut, 6. Manavgat and 7. Kopru. 1-4 and 6-7 represent two separate tectonically active depocenters, whereas 5 was a relatively stable platform. The early-mid Miocene of Hatay Basin contains sparse zircons with Precambrian (570-900 Ma) and Cretaceous (73-99 Ma) populations that become prominent in the mid-late Miocene. The early Miocene of K.Maraş Basin has abundant Pan-African, Grenvillian and Eocene zircons; mid-Miocene exhibits scarce Neoproterozoic-Mesoproterozoic but abundant Cretaceous-Neogene zircons. The late Oligocene-early Miocene of Adana Basin has minor Cretaceous-Neogene zircons, becoming more abundant in the early Miocene. The Miocene of Misis Basin has abundant Precambrian grains, mainly restricted to the NE. The Miocene of Mut Basin has major zircon populations of 544-710 Ma, 730-990 Ma, and two subordinate 1700-2000 Ma and 2400-2700 Ma clusters. Early Miocene (17-19 Ma) zircons occur in some samples. The Manavgat Basin samples are similar to the Mut Basin ones but with more evidence of mid-late Miocene (8-14 Ma) zircons. Lastly, the Kopru Basin (E Isparta Angle) has Pan-African (540-640 Ma) and Grenvillian (810-1000 Ma) populations, and small Paleozoic clusters. The Pan-African and Grenvillian-aged material was probably supplied directly and/or recycled from rifted Gondwanan Cadomian ‘basement’ and its Paleozoic passive margin cover, as partly exposed in south/central Anatolia. Sparse Permian-Triassic zircons relate to Neotethyan rifting. Late Cretaceous-early Cenozoic grains were derived from adjacent Late Cretaceous ophiolitic, magmatic arc and related metamorphic units. Early Miocene zircons relate to local basaltic volcanism. The variable zircon abundances hint at differential exhumation/erosion. Two regional drainage system dominated, one through the K.Maraş basin system (E) and the other through the Isparta Angle basin system (W).

Committees touch nearly every facet in the science, technology, engineering, and mathematics (STEM) research enterprise. However, the role of gatekeeping through committee work has received little attention in Earth and space sciences. We propose a novel concept called, “regenerative gatekeeping” to challenge institutional inertia, cultivate belonging, accessibility, justice, diversity, equity, and inclusion in committee work. Three examples, a hiring committee process, a seminar series innovation, and an awards committee, highlight the need to self-assess policies and practices, ask critical questions and engage in generative conflict. Rethinking committee work can activate distributed mechanisms needed to promote change.

Urbanization increases runoff, sediment, and nutrient loadings to freshwaters, causing flooding, harmful algal blooms, and increased costs for drinking water filtration. Most watershed models use runoff quality data from specific land uses; coupled with a variety of methods for quantifying loads, the most common being Build-up and Wash-off (BUWO) equations for which loading is a function of antecedent dry period (ADP). However, several studies have shown there is no significant correlation between urban runoff quality and ADP, suggesting predictions based solely on landuse and ADP are questionable. The objective of this study is to discover which parameters, climatological or catchment characteristics, are most significant and should be included in the BUWO relationship. Stormwater quality data was obtained from the National Stormwater Quality Database (NSQD), which is the largest and most recent database of its type in the U.S. Bayesian Network Structure Learner (BNSL) was used to assess the relationships between catchment characteristics, climatological information, and runoff quality for each land use. Given the optimal BN structure, it was determined which parameters affect water quality event mean concentrations the most, and which the least. The results demonstrated that for some constituents (i.e. particulate nitrogen, particulate phosphorous, and sediments), other factors (such as rainfall depth and duration, surface slope) exert a more important influence on urban runoff quality than ADP.

Earthquake occurrence in the stress shadow provides a unique opportunity for extracting the information about the physical processes behind earthquakes because it highlights processes other than the ambient stress change in earthquake generation. In this study, we examined the fault structure and the spatiotemporal distribution of the aftershocks of the 2019 M6.7 Yamagata-Oki earthquake, which occurred in the stress shadow of the 2011 M9.0 Tohoku-Oki earthquake, to better understand the earthquake generation mechanism. Moreover, we investigated the temporal evolution of the surface strain rate distribution in the source region by using GNSS data. The earthquake detection and hypocenter relocation succeeded in delineating three planar structures of earthquakes. The results suggest that individual aftershocks were caused by a slip on the macroscopic planar structures. Aftershock hypocenters rapidly migrated upward from the deeper part of the major plane (fault) similar to the recent earthquake swarm sequences triggered by the 2011 Tohoku-Oki earthquake in the stress shadow in the upper plate. East–west contraction strain rate in the source region of the Yamagata-Oki earthquake with E–W compressional reverse fault mechanism changed to the E–W extension as a result of Tohoku-Oki earthquake, and it continued until the occurrence of the Yamagata-Oki earthquake. The upward hypocenter migrations, together with the earthquake occurrence in the stress shadow and in the E–W extension strain rate field, suggest that the reduction in the fault strength due to the uprising fluids contributed to the occurrence of this earthquake sequence. Localized aseismic deformations, such as aseismic creeps, beneath the fault zone may also have contributed to the earthquake occurrence. The results support the hypothesis that aseismic processes in the deeper part of the fault play crucial roles in the occurrence of shallow intraplate earthquakes.

After the 2016 Gyeongju Earthquake (MW 5.5) in SE Korea, the NNE‒SSW-striking Yangsan Fault (YF) seismicity has emerged as a significant scientific issue and hazard. Despite previous studies of the seismicity of the YF, the paleoseismic information of the fault remain uncertain. We carried out paleoseismic investigations to characterize surface rupturing and the paleoseismic history of the northern section of the southern YF. Deflected streams and displaced river terraces indicate a dextral sense of slip, and fault splays cutting unconsolidated sedimentary strata in trench walls show an east-side-up geometry. The dextral strike-slip faulting with a minor reverse component is characterized by several noticeable stratigraphic features, including fissure-filling deposits, sag ponds, and cut-and-fill streams along the fault splay. Based on fault‒sediment cross-cutting relationships and optically stimulated luminescence ages of unconsolidated sediments, we propose two possible rupture scenarios for the most recent earthquake event along the studied fault section during the Late Pleistocene: (1) a single rupture along the entire section (WS‒MH‒IBN‒IB) at ca. 30 ka and (2) individual partial ruptures along two segments of the section (WS‒MH and IBN‒IB) during 33‒30 and 29‒17 ka, respectively. It is also noted that the timings of earlier ruptures (penultimate earthquake events) of the two segments are 37‒35 and 70‒52 ka, respectively. Furthermore, the timing(s) of the most recent earthquake for our studied section is much older than that of the southern section of the northern YF.

The explosive eruption of the Hunga-Tonga volcano in the southwest Pacific at 0415UT on 15 January 2022 triggered gigantic atmospheric disturbances with surface air pressure wave propagating around the globe in Lamb mode. In space, concentric traveling ionosphere disturbances (CTIDs) are also observed as a manifestation of air pressure acoustic waves in New Zealand ~0500UT and Australia ~0630UT. As soon as the wave reached central Australia ~0800UT, CTIDs appeared simultaneously in the northern hemispheres through magnetic field line conjugate effect, which is much earlier than the arrival of the air pressure wave to Japan after 1100UT. Combining observations over Australia and Japan between 0800-1000UT, CTIDs with characteristics of phase velocities of 320-390 m/s are observed, matching with the dispersion relation of Lamb mode. The arrival of atmospheric Lamb wave to Japan later created in situ CTIDs showing the same Lamb mode characteristics as the earlier arriving CTIDs.

Sedimentary bed configurations that are stable under weak fluid-driven transport conditions can be divided into two groups: (1) meso-scale features that influence flow and sediment transport through roughness and drag partitioning effects (“mesoforms”), and (2) grain-scale features that can effectively be ignored at the macroscopic scale (“microforms”). In practice, these groups delineate ripples and dunes from quasi-planar bed configurations. They are thought to be separated by a transition in processes governing the relief of the bed; however, the physical mechanisms responsible for this transition are poorly understood. Previous studies suggest that planar topography is unstable when interactions between moving particles lead to stabilized bed disturbances that initiate morphodynamic pattern coarsening. This study presents a kinetic interpretation of this hypothesis in terms of parameters describing particle motion. We find that the microform/mesoform transition corresponds to a critical transition in particle behavior associated with increasing importance of particle collisions. This transition also corresponds to the point where continuum-based morphodynamic models are permissible at the most unstable wavelength predicted from linear stability theory, providing a link between descriptive and mathematical theories of bedform initiation.

The EXospheric TEMeratures on a PoLyhedrAl gRid (EXTEMPLAR) method predicts the neutral densities in the thermosphere. The performance of this model has been evaluated through a comparison with the Air Force High Accuracy Satellite Drag Model (HASDM). The Space Environment Technologies (SET) HASDM database that was used for this test spans the 20 years 2000 through 2019, containing densities at 3 hour time intervals at 25 km altitude steps, and a spatial resolution of 10 degrees latitude by 15 degrees longitude. The upgraded EXTEMPLAR that was tested uses the newer Naval Research Laboratory MSIS 2.0 model to convert global exospheric temperature values to neutral density as a function of altitude. The revision also incorporated time delays that varied as a function of location, between the total Poynting flux in the polar regions and the exospheric temperature response. The density values from both models were integrated on spherical shells at altitudes ranging from 200 to 800 km. These sums were compared as a function of time. The results show an excellent agreement at temporal scales ranging from hours to years. The EXTEMPLAR model performs best at altitudes of 400 km and above, where geomagnetic storms produce the largest relative changes in neutral density. In addition to providing an effective method to compare models that have very different spatial resolutions, the use of density totals at various altitudes presents a useful illustration of how the thermosphere behaves at different altitudes, on time scales ranging from hours to complete solar cycles.

Floodplain inundation links river and land systems through significant water, sediment, and nutrient exchanges. However, these two-way interactions between land and river are currently missing in most Earth System Models. In this study, we introduced the two-way hydrological coupling between the land component, ELM, and the river component, MOSART, in Energy Exascale Earth System Model (E3SM) to study the impacts of floodplain inundation on land and river processes. We calibrated the river channel geometry and developed a new data-driven inundation scheme to improve the simulation of inundation dynamics in E3SM. The new inundation scheme captures 96% of the spatial variation of inundation area in a satellite inundation product at global scale, in contrast with 7% when the default inundation scheme of E3SM was used. Global simulations including the new inundation scheme performed at resolution with and without two-way land-river coupling were used to quantify the impact of coupling. Comparisons show that two-way coupling modifies the water and energy cycle in 20% of the global land cells. Specifically, riverine inundation is reduced by two-way coupling, but inland inundation is intensified. Wetter periods are more impacted by the two-way coupling at the global scale, while regions with different climates exhibit different sensitivities. The two-way exchange of water between the land and river components of E3SM provides the foundation for enabling two-way coupling of land-river sediment and biogeochemical fluxes. These capabilities will be used to improve understanding of the interactions between water and biogeochemical cycles and their response to human perturbations.

Heavy precipitation events (HPEs) can lead to deadly and costly natural disasters and are critical to the hydrological budget in regions where rainfall variability is high and water resources depend on individual storms. Thus, reliable projections of such events in the future are needed. To provide high-resolution projections under the RCP8.5 scenario for HPEs at the end of the 21st century and to understand the changes in sub-hourly to daily rainfall patterns, weather research and forecasting (WRF) model simulations of 41 historic HPEs in the eastern Mediterranean are compared with “pseudo global warming” simulations of the same events. This paper presents the changes in rainfall patterns in future storms, decomposed into storms’ mean conditional rain rate, duration, and area. A major decrease in rainfall accumulation (-30% averaged across events) is found throughout future HPEs. This decrease results from a substantial reduction of the rain area of storms (-40%) and occurs despite an increase in the mean conditional rain intensity (+15%). The duration of the HPEs decreases (-9%) in future simulations. Regionally maximal 10-min rain rates increase (+22%), whereas over most of the region, long-duration rain rates decrease. The consistency of results across events, driven by varying synoptic conditions, suggests that these changes have low sensitivity to the specific large-scale flow during the events. Future HPEs in the eastern Mediterranean will therefore likely be drier and more spatiotemporally concentrated, with substantial implications on hydrological outcomes of storms.

Shock waves are common in the heliosphere and beyond. The collisionless nature of most astrophysical plasmas allows for the energy processed by shocks to be partitioned amongst particle sub-populations and electromagnetic fields via physical mechanisms that are not well understood. The electrostatic potential across such shocks is frame dependent. In a frame where the incident bulk velocity is parallel to the magnetic field, the deHoffmann-Teller frame, the potential is linked directly to the ambipolar electric field established by the electron pressure gradient. Thus measuring and understanding this potential solves the electron partition problem, and gives insight into other competing shock processes. Integrating measured electric fields is space is problematic since the measurements can have offsets that change with plasma conditions. The offsets, once integrated, can be as large or larger than the shock potential. Here we exploit the high-quality field and plasma measurements from NASA's Magnetospheric Multiscale mission to attempt this calculation. We investigate recent adaptations of the deHoffmann-Teller frame transformation to include time variability, and conclude that in practise these face difficulties inherent in the 3D time-dependent nature of real shocks by comparison to 1D simulations. Potential estimates based on electron fluid and kinetic analyses provide the most robust measures of the deHoffmann-Teller potential, but with some care direct integration of the electric fields can be made to agree. These results suggest that it will be difficult to independently assess the role of other processes, such as scattering by shock turbulence, in accounting for the electron heating.

Solar wind magnetic holes are localized depressions of the magnetic field strength, on time scales of seconds to minutes. We use Cluster multipoint measurements to identify 26 magnetic holes which are observed just upstream of the bow shock and, a short time later, downstream in the magnetosheath, thus showing that they can penetrate the bow shock and enter the magnetosheath. For two magnetic holes we show that the relation between upstream and downstream properties of the magnetic holes are well described by the MHD Rankine-Hugoniot jump conditions. We also present a small statistic investigation of the correlation between upstream and downstream observations of some properties of the magnetic holes. The temporal scale size, and magnetic field rotation across the magnetic holes are very similar for the upstream and downstream observations, while the depth of the magnetic holes varies more. The results are consistent with the interpretation that magnetic holes in Earth's and Mercury's magnetosheath are of solar wind origin, as has earlierly been suggested. Since the solar wind magnetic holes can enter the magnetosheath, they may also interact with the magnetopause, representing a new type of localised solar wind-magnetosphere interaction.

Cirrus clouds of various thicknesses and radiative characteristics extend over much of the tropics, especially around deep convection. They can be difficult to observe due to their high altitude and sometimes small optical depths. They are also difficult to simulate in conventional global climate models, which have coarse grid spacings and simplified parameterizations of deep convection and cirrus formation. We investigate the representation of tropical cirrus in global storm-resolving models (GSRMs), which have higher spatial resolution and explicit convection and could more accurately represent cirrus cloud processes. This study uses GSRMs from the DYnamics of the Atmospheric general circulation Modeled On Non-hydrostatic Domains (DYAMOND) project. The aggregate life cycle of tropical cirrus is analyzed using joint albedo and outgoing longwave radiation (OLR) histograms to assess the fidelity of models in capturing the observed cirrus cloud populations over representative tropical ocean and land regions. The proportions of optically-thick deep convection, anvils, and cirrus vary across models and are reflected in the vertical distribution of cloud cover and top-of-atmosphere radiative fluxes. Model differences in cirrus populations, likely driven by subgrid processes such as ice microphysics, dominate over regional differences between convectively-active tropical land and ocean locations.

Urbanization and climate change are exacerbating stress on aging urban critical infrastructure systems, including water, energy, mobility, and telecommunication networks. Simulation tools and scenario analyses able to capture the interdependencies among these different infrastructure systems are crucial to support decision making and realize sustainable and resilient development. Yet, existing simulation tools are mostly developed within the boundaries of individual application sectors and information often remains siloed, despite the increasing data and computational opportunities offered by the digital transformation of many infrastructure sectors. In this work, we present how the ide3a project (international alliance for digital e-learning, e-mobility and e-research in academia – https://ide3a.net) addresses this research gap. ide3a is building a digital campus to support digital learning, research, and mobility in collaboration within a network of six European partner universities. Several senior and early career researchers with multidisciplinary backgrounds in water management, IT systems, mobility, energy, urban planning, sustainability, and psychology, work together to integrate state-of-the-art research on critical infrastructure and digitalization into traditional higher education curricula. As part of the ide3a portfolio of digital tools for learning and research, we present a prototype of “ConnectiCity”, an open-source simulation-based serious game that integrates multi-sectoral models to perform simulations of interconnected critical infrastructure systems and quantify cascading effects under various climate, social, and technical scenarios. Along with other ide3a activities, it is used to train early career researchers and students alike to enrich their transdisciplinary knowledge, foster critical system thinking, drive research on urban critical infrastructure dynamics, and ultimately working across disciplines to tackle contemporary urban challenges.

The ozonesonde observations in Hanoi, Vietnam, over fourteen years since 2004 have confirmed the enhancement in lower tropospheric ozone concentration at about 3 km altitude in the spring season. We investigated the evolution of the ozone enhancement from analysis of meteorological data, backward trajectories, and model sensitivity experiments. In spring, air masses over Hanoi exhibit strong height dependence. At 3km, the high-ozone air masses originate from the land area to the west of Hanoi, while low-ozone air masses below about 1.5 km are from the oceanic area to the east. Above 4 km, the air masses are mostly traced back to the farther west area. The chemical transport model simulations revealed that precursor emissions from biomass burning in the inland Indochina Peninsula have the largest contribution to the lower tropospheric ozone enhancement, which is transported upward and eastward and overhangs the clean air intrusion from the ocean to the east of Hanoi. At this height level, the polluted air has the horizontal extent of about 20 degrees in longitude and latitude. The polluted air observed in Hanoi is transported further east and widely spread over the northern Pacific Ocean.