Regionalization approaches wherein utilities in close geographic proximity cooperate to manage drought risks and co-invest in new infrastructure are increasingly necessary strategies for leveraging economies of scale to meet growing demands and navigate deeply uncertain risks. Successful regional cooperative investment and management pathways, however, must equitably balance the interests of multiple partners while navigating power relationships between regional actors. In long-term infrastructure planning contexts, this challenge is heightened by the evolving system-state dynamics, which may be fundamentally reshaped by infrastructure investment. This work introduces Equitable, Robust, Adaptive, and Stable Deeply Uncertain Pathways (DU PathwaysERAS), an exploratory modeling framework for developing regional water supply management and infrastructure investment pathways. Our framework explores equity and power relationships within cooperative pathways using multiple rival framings of robustness, each representing a competing hypothesis about how performance objectives should be prioritized. To capture the time-evolving dynamics of infrastructure pathways, DU PathwaysERAS features new tools to measure the adaptive capacity of pathway policies and evaluate time-evolving vulnerability. We demonstrate our framework on a six-utility water supply partnership seeking to develop cooperative infrastructure investment pathways in the Research Triangle, North Carolina. Our results indicate that commonly employed framings of robustness can have large and unintended adverse consequences for regional equity. Results further illustrate that regional and individual vulnerabilities are highly interdependent, emphasizing the need to craft agreements that limit counterparty risks from the actions of cooperating partners. Beyond the Research Triangle, these results are broadly applicable to cooperative water supply infrastructure investment and management globally.

Cosmogenic exposure data can be used to calculate time-varying fault slip rates on normal faults with exposed bedrock scarps. However, the method relies on assumptions related to how the scarp is preserved, which should be consistent at multiple locations along the same fault. Previous work commonly relied on cosmogenic data from a single sample locality to determine the slip rate of a fault. Here we show that by applying strict sampling criteria and using geologically informed modelling parameters in a Bayesian-inference Markov chain Monte Carlo method, similar patterns of slip rate changes can be modelled at multiple sites on the same fault. Consequently, cosmogenic data can be used to resolve along-strike fault activity. We present cosmogenic 36Cl concentrations from seven sites on two faults in the Italian Apennines. The average slip rate varies between sites on the Campo Felice Fault (0.84 0.23 to 1.61 0.27 mm yr ^-1), and all sites experienced a period of higher than average slip rate between 0.5 and 2 ky and a period of lower than average slip rate before 3 ky. On the Roccapreturo fault, slip rate in the centre of the fault is 0.550.11 and 0.350.05 mm yr ^-1 at the fault tip near a relay. The estimated time since the last earthquake is the same at each site along the same fault. These results highlight the potential for cosmogenic exposure data to reveal the detailed millennial history of earthquake slip on active normal faults.

Atmospheric dust is a more extreme modifier of weather and climate on Mars than water vapor is on Earth. Global dust storms enshroud Mars in a veil of dust for months and have major implications for past and present climate, geologic history, habitability, and exploration. Yet their mysterious origins mean we remain unable to realistically simulate or predict them. In this White Paper, we find that key Knowledge Gaps are: A. how dust is lifted; B. constraints on near-surface winds and boundary-layer processes; C. the distribution of mobile surface dust; and D. the key processes and feedbacks by which dust storms begin and evolve. To make progress in the next decade, we make four Recommendations in order of priority: #1. Properly accommodate a minimum payload of meteorological and aeolian sensors on future Mars surface missions; #2. Continue orbital monitoring of the evolving surface dust distribution; #3. Expand orbital measurements to include winds and full diurnal coverage; and #4. Continue orbital monitoring and add surface measurements of aerosols during dust storms.

The physical circulation of the Southern Ocean sets the surface concentration and thus air-sea exchange of CO2. However, we have a limited understanding of the three-dimensional circulation that brings deep carbon-rich waters to the surface. Here, we introduce and analyze a novel high-resolution ocean model simulation with active biogeochemistry and online Lagrangian particle tracking. We focus our attention on a subset of particles with high dissolved inorganic carbon (DIC) that originate below 1000 m and eventually upwell into the surface mixed layer. We find that 71% of the DIC-enriched water upwelling across 1000 m is concentrated near topographic features, which occupy just 33% of the Antarctic Circumpolar Current. Once particles upwell to the surface mixed layer, their DIC decorrelates on timescales of ~1.5 months—an order of magnitude longer than their residence time. Our results show that Southern Ocean bathymetry plays a key role in delivering carbon-rich waters to the surface.

IDN Penelitian ini dilakukan dengan tujuan untuk memetakan pola aliran air tanah di sekitar Kali Sumpil di wilayah Kota Malang. Lokasi penelitian ini adalah di segmen Kali Sumpil sepanjang 5,6 km yang mengalir mulai dari Kecamatan Lowokwaru hingga ke pertemuan antara Kali Sumpil dan Kali Sari di Kecamatan Blimbing, Kota Malang. Pola aliran air tanah di lokasi penelitian dipetakan berdasarkan elevasi muka air tanah yang diukur dari 43 lokasi sumur gali milik warga yang tersebar di sepanjang aliran Kali Sumpil tersebut. Elevasi muka air tanah pada sumur gali warga di lokasi penelitian berkisar antara +493,88 m dpl di bagian hulu hingga +436,70 m dpl di bagian hilir. Elevasi muka air tanah tertinggi berada pada sumur gali SG-26 yang berada di sebelah kanan aliran bagian hulu Kali Sumpil, sedangkan elevasi muka air tanah terendah berada pada sumur gali SG-25 di sebelah kiri aliran bagian hilir Kali Sumpil. Secara umum, aliran air tanah di lokasi penelitian mengalir dari arah Barat Laut menuju ke arah Tenggara bersesuaian dengan arah aliran Kali Sumpil. Hubungan antara air tanah dan air permukaan adalah air tanah mengisi air permukaan Kali Sumpil. EN The objective of this study is to mapping the groundwater flow patterns around Sumpil River in Malang City. The location of this study is in one of the segments of Sumpil River along the 5.6 km which flows from Lowokwaru District to the confluence of Sumpil River and Sari River in Blimbing District, Malang City. The groundwater flow pattern in the area of the study was mapped based on the groundwater level measured from 43 resident’s dug wells scattered along Sumpil River. The groundwater level in the area of the study ranges from +493,88 m asl in the upstream area to +436,70 m asl in the downstream area. The highest groundwater level is in the SG-26 which is located to the right of the upstream flow of the Sumpil River, while the lowest groundwater level is in the SG-25 to the left of the downstream flow of the Sumpil River. In general, groundwater flow in the area of study flows from the Northwest to the Southeast in accordance with the direction of the Sumpil River flow. The interaction between groundwater and surface water is the groundwater flows to Sumpil River (gaining stream).

Seismicity models are probabilistic forecasts of earthquake rates to support seismic hazard assessment. Physics-based models allow extrapolating previously unsampled parameter ranges and enable conclusions on underlying tectonic or human-induced processes. The Coulomb Failure (CF) and the rate-and-state (RS) models are two widely-used physics-based seismicity models both assuming pre-existing populations of faults responding to Coulomb stress changes. The CF model depends on the absolute Coulomb stress and assumes instantaneous triggering if stress exceeds a threshold, while the RS model only depends on stress changes. Both models can predict background earthquake rates and time-dependent stress effects, but the RS model with its three independent parameters can additionally explain delayed aftershock triggering. This study introduces a modified CF model where the instantaneous triggering is replaced by a mean time-to-failure depending on the absolute stress value. For the specific choice of an exponential dependence on stress and a stationary initial seismicity rate, we show that the model leads to identical results as the RS model and reproduces the Omori-Utsu relation for aftershock decays as well stress-shadowing effects. Thus, both CF and RS models can be seen as special cases of the new model. However, the new stress response model can also account for subcritical initial stress conditions and alternative functions of the mean time-to-failure depending on the problem and fracture mode.

Rainfall runoff and leaching are the main driving forces that nitrogen, an important non-point source (NPS) pollutant, enters streams, lakes and groundwater. Hydrological processes thus play a pivotal role in NPS pollutant transport. However, existing environmental models often use oversimplified hydrological components and do not properly account for overland flow process. To better track the pollutant transport at a watershed scale, a new model is presented by integrating nitrogen-related processes into a comprehensive hydrological model, the Distributed Hydrology Soil and Vegetation Model (DHSVM). This new model, called DHSVM-N, features a nitrate transport process at a fine resolution, incorporates landscape connectivity, and enables proper investigations of the interactions between hydrological and biogeochemical processes. Results from the new model are compared with those based on Soil & Water Assessment Tool (SWAT). The new model is shown capable of capturing the “hot spots” and spatial distribution patterns of denitrification, reflecting the important role in which heterogeneity of the watershed characteristics plays. In addition, a set of control experiments are designed using DHSVM-N and its variant to study the respective role of hydrology and nitrate transport process in modeling the denitrification process. Our results highlight the importance of adequately representing hydrological processes in modeling denitrification. Results also manifest the importance of having a good transport model with accurate flow pathways that considers realistic landscape connectivity and topology in identifying the denitrification hot spots and in properly estimating the amount of nitrate removed by denitrification.

Accounting for an accurate noise model is essential when dealing with real data which are noisy due to the effect of environmental noise, failures and limitations in data acquisition and processing. Quantifying the noise model is a challenge for practitioners in formulating an inverse problem and usually, a simple Gaussian noise model is assumed as a white noise model. Here we propose a pragmatic approach to using an estimated seismic wavelet to capture the correlated noise model (coloured noise) for the processed reflection seismic data. We test the method for a probabilistic sampling-based inversion where post-stack seismic data, associated with a hard carbonate reservoir in southwest Iran, is inverted directly to porosity. We assume eight different scenarios for the bandwidth and the magnitude of the noise. The investigation of the corresponding posterior statistics shows that ignoring the correlation of the noise samples in the noise covariance matrix generates unrealistic features in porosity realisations while underestimating the noise magnitude leads to overfitting the data and generating a biased model with low uncertainty. Furthermore, by considering an imperfect bandwidth for the noise model, the error is propagated to the posterior realisations. These issues are resolved considerably when the correlated noise is considered in the inversion. Therefore, in real data applications where the estimation of the magnitude and correlations of the noise is not trivial, the estimated seismic wavelet provides a good proxy for describing the correlation of the noise samples or equivalently the bandwidth of the noise model. In addition, it might be better to overestimate the noise magnitude than to underestimate it. This is true especially for an uncorrelated noise model and to a lesser degree also for the correlated noise model.

Water analyses typically result in numerous characteristic values. The bunch of parameters hamper temporal or spatial comparisons of different samples. In order to facilitate the evaluation and interpretation of hydrochemical data, hydrogeologists use various special diagrams. One of them is the Schoeller diagram, in which concentrations of different species are plotted on logarithmic scales. Entries of an analysis are connected and form a characteristic signature. In the Schoeller diagram, parallel or subparallel signatures indicate relatedness of waters. Here we present the idea of standardized Schoeller diagrams: different logarithmic axes are shifted with respect to each other, in order for the signature of a selectable sample to form a straight line. This standardization greatly facilitates the comparison of water samples to the chosen standard and increases the informative value of a Schoeller diagram. As to our knowledge, there is no software that could generate standardized Schoeller diagrams, we have developed a Matlab tool for this purpose. The tool is available for free and allows fast generation of standardized Schoeller diagrams with many possibilities to implement user-specific wishes. We hope that this tool will contribute to a wider use of Schoeller diagrams.

Solar eruptions cause geomagnetic storms in the near-Earth environment, creating spectacular aurorae visible to the human eye and invisible dynamic changes permeating all of geospace. Just equatorward of the aurora, radars and satellites often observe intense westward plasma flows called subauroral polarization streams (SAPS) in the dusk-to-midnight ionosphere. SAPS occur across a narrow latitudinal range and lead to intense frictional heating of the ionospheric plasma and atmospheric neutral gas. SAPS also generate small-scale plasma waves and density irregularities that interfere with radio communications. As opposed to the commonly observed duskside SAPS, intense eastward subauroral plasma flows in the morning sector were recently discovered to have occurred during a super storm on 20 November 2003. However, the origin of these flows termed “dawnside SAPS” could not be explained by the same mechanism that causes SAPS on the duskside and has remained a mystery. Through real-event global geospace simulations, here we demonstrate that dawnside SAPS can only occur during major storm conditions. During these times the magnetospheric plasma convection is so strong as to effectively transport ions to the dawnside, whereas they are typically deflected to the dusk by the energy-dependent drifts. Ring current pressure then builds up on the dawnside and drives field-aligned currents that connect to the subauroral ionosphere, where eastward SAPS are generated. The origin of dawnside SAPS explicated in this study advances our understanding of how the geospace system responds to strongly disturbed solar wind driving conditions that can have severe detrimental impacts on human society and infrastructure.

Intense convection (updrafts exceeding 10 m∙s-1) plays an essential role in severe weather and Earth’s energy balance. Despite its importance, how the global pattern of intense convection changes in response to warmed climates remains unclear, as simulations from traditional climate models are too coarse to simulate intense convection. Here we take advantage of a kilometer-scale global storm resolving model and conduct year-long simulations of a control run, forced by analyzed sea surface temperature (SST), and one with a 4-K increase in SST for comparison. Comparisons show that the increased SST enhances the frequency of intense convection globally with large spatial and seasonal variations. Increases in the intense convection frequency do not necessarily reflect increases in convective available potential energy (CAPE). Results are also compared with traditional climate model projections. Changes in the spatial pattern of intense convection are associated with changes in planetary circulation.

In near-Earth space, variations in thermospheric composition have important implications for thermosphere-ionosphere coupling. The ratio of O to N2 is often measured using far-UV airglow observations. Taking such airglow observations from space, looking below the Earth’s limb allows for the total column of O and N2 in the ionosphere to be determined. While these observations have enabled many previous studies, determining the impact of non-migrating tides on thermospheric composition has proved difficult, owing to a small contamination of the signal by recombination of ionospheric O+. New ICON observations of far UV are presented here, and their general characteristics are shown. Using these, along with other observations and a global circulation model we show that under certain circumstances the impact of non-migrating tides on thermospheric composition can be observed. By comparing the amplitude of the variation seen with that in the model, both the utility of these observations and a pathway to enable future studies is shown.

Stable water isotopologues tend to fractionate from ordinary water during evaporation processes resulting in an enrichment of the isotopic species in the soil. The fractionation process can be split into equilibrium fractionation and kinetic fractionation. Due to the complex coupled processes involved in simulating soil-water evaporation accurately, defining the kinetic fractionation correctly remains an open research area. In this work, we present a multi-phase multi-component transport model that resolves flow through both the near surface atmosphere and the soil, and models transport and fractionation of the stable water isotopologues using the numerical simulation environment DuMuX. Using this high resolution coupled model, we simulate transport and fractionation processes of stable water isotopologues in soils and the atmosphere without further parameterization of the kinetic fractionation process as is commonly done. In a series of examples, the transport and distribution of stable-water isotopologues are evaluated numerically with varied conditions and assumptions. First, an unsaturated porous medium connected to constant laminar flow conditions is introduced. The expected vertical isotope profiles in the soil as described in literature are reproduced. Further, by examining the spatial and temporal distribution of the isotopic composition, is determined the enrichment of the isotopologues in soil is linked with the different stages of the evaporation process. Building on these results, the robustness of the isotopic fractionation in our model is analysed by isolating single fractionation parameters. The effect of wind velocity and turbulent atmospheric conditions is investigated, leading to different kinetic fractionation scenarios and varied isotopic compositions in the soil.

Advances in high-performance computing have enabled large-eddy simulations (LES) of turbulence, convection, and clouds, but their potential to improve parameterizations in global climate models (GCMs) is only beginning to be harnessed. We design an experimental setup in which LES can be driven by large-scale forcings from GCMs. This can be done anywhere in the atmosphere, and we use this setup to create a library of LES of clouds across tropical and subtropical regimes. The LES are used to simulate the transition from stratoculumus to shallow cumulus over the East Pacific. The results are not very sensitive to the choice of the host GCM driving the LES. The setup is also used to simulate clouds under climate change. The LES simulate a positive but weak shortwave cloud feedback. The LES library expands the datasets available for calibrating parameterizations in GCMs.

Due to differences in solar illumination, a geomagnetic field line may have one footpoint in a dark ionosphere while the other ionosphere is in daylight. This may happen near the terminator under solstice conditions. In this situation, a resonant wave mode may appear which has a node in the electric field in the sunlit (high conductance) ionosphere and an antinode in the dark (low conductance) ionosphere. Thus, the length of the field line is one quarter of the wavelength of the wave, in contrast with half-wave field line resonances in which both ionospheres are nodes in the electric field. These quarter waves have resonant frequencies that are roughly a factor of 2 lower than the half-wave frequency on the field line. We have simulated these resonances using a fully three-dimensional model of ULF waves in a dipolar magnetosphere. The ionospheric conductance is modeled as a function of the solar zenith angle, and so this model can describe the change in the wave resonance frequency as the ground magnetometer station varies in local time. The results show that the quarter-wave resonances can be excited by a shock-like impulse at the dayside magnetosphere and exhibit many of the properties of the observed waves. In particular, the simulations support the notion that a conductance ratio between day and night footpoints of the field line must be greater than about 5 for the quarter waves to exist.

The current approaches have known limitations to understanding the coupling of terrestrial ecosystem evapotranspiration (ET) and photosynthesis (referred to as gross primary productivity, GPP). To better characterize the relationship between ET and GPP, we developed a novel remote sensing (RS)-driven approach (RCEEP) based on the underlying water use efficiency (uWUE). RCEEP partitions transpiration (T) from ET using a RS vegetation index (VI)-derived ratio of T to ET (VI-fT) and then links T and GPP via RS VI-derived Gc (VI-Gc) rather than leaf-to-air vapor pressure difference. RCEEP and other two uWUE versions (VI-T or VI-G), which only incorporate VI-fT or VI-Gc , were evaluated and compared with the original uWUE model in terms of their performances (Nash-Sutcliffe efficiency, NSE) in estimating GPP from ET over 180 flux sites covering 11 biome types over the globe. Results revealed better performances of VI-T and VI-G compared to the original uWUE, implying remarkable contributions of VI-fT and VI-Gc to a more meaningful relationship between ET and GPP. RCEEP yielded the best performances with a reasonable mean NSE value of 0.70 (0.76) on a daily (monthly) scale and across all biome types. Further comparisons of RCEEP and approaches modified from recent studies revealed consistently better performances of RCEEP and thus, positive implications of introducing VI-fT and VI-Gc in bridging ecosystem ET and GPP. These results are promising in view of improving or developing algorithms on coupled estimates of ecosystem ET and GPP and understanding the GPP dynamics concerning ET on a global scale.

Hydrological alterations, which can be represented by the extent of the changes in the flow patterns resulting from anthropogenic factors, can reduce aquatic biodiversity by disrupting the life cycles of organisms. However, past studies have faced difficulties in quantifying the impacts of dams and climate change, which are major drivers of hydrological alterations. Here, we aimed to evaluate and compare the hydrological alterations caused by dams and climate change throughout the Omaru River catchment, Japan, using a distributed hydrological model. First, to assess the impacts of dam and climate change independently, we performed runoff analyses using either dam discharge or future climatic data (two future periods × three representative concentration pathways; RCPs). Subsequently, we derived indicators of hydrologic alterations (IHA) to quantify changes in flow alterations by comparing them to IHA under natural conditions (i.e., without dam or climate change data). The runoff analyses showed high reproducibility throughout the study period (Nash-Sutcliffe efficiency = 0.921–0.964). We found that dams altered IHAs more than climate change. However, on a catchment-scale standpoint, climate change induced wider ranges of flow alterations, such as low flow metrics along the tributaries and uppermost main stem, suggesting a watershed-level shrinkage in important corridors of aquatic organisms by reducing upstream length and water level. We also observed that the altered flow by water withdrawals were ameliorated by the confluence of tributaries and downstream hydropower outflows. Our approach, which used a distributed hydrological model, developed a better understanding of flow alterations by dams and climate change.

Identifying the causes for historical sea-level changes in coastal tide-gauge records is important for constraining oceanographic, geologic, and climatic processes. The Río de la Plata estuary in South America features the longest tide-gauge records in the South Atlantic. Despite the relevance of these data for large-scale circulation and climate studies, the mechanisms underlying relative sea-level changes in this region during the past century have not been firmly established. I study annual data from tide gauges in the Río de la Plata and stream gauges along the Río Paraná and Río Uruguay to establish relationships between river streamflow and sea level over 1931-2014. Regression analysis suggests that streamflow explains 59%+/-17% of the total sea-level variance at Buenos Aires, Argentina, and 28%+/-21% at Montevideo, Uruguay (95% confidence intervals). A longterm streamflow increase effected sea-level trends of 0.71+/-0.35 mm/yr at Buenos Aires and 0.48+/-0.38 mm/yr at Montevideo. More generally, sea level at Buenos Aires and Montevideo respectively rises by (7.3+/-1.8)x10^-6 m and (4.7+/-2.6)x10^-6 m per 1 m^3 s^-1 streamflow increase. These observational results are consistent with simple theories for the coastal sea-level response to streamflow forcing, suggesting a causal relationship between streamflow and sea level mediated by ocean dynamics. Findings advance understanding of local, regional, and global sea-level changes, clarify sea-level physics, inform future projections of coastal sea level and the interpretation of satellite data and proxy reconstructions, and highlight future research directions.