bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of faults and fractures in mudstone seal rocks of porous-media underground hydrogen storage reservoirs – Case study in Taranaki, New Zealand
Authors: Yates Edward , Nicol Andy , Parker Matthew , Dempsey David
Published: March 2024

Hydrogen is projected to account for at least 10% of the global energy system in 20 years and is a critical component of the future zero-emissions energy system. Underground storage of green hydrogen in Aotearoa New Zealand (ANZ) will take advantage of intermittent surplus of renewable electricity at low cost, balance seasonal fluctuations in energy supply and demand, and provide a strategic reserve of energy. This poster is part of a larger research programme primarily focused on investigating the potential for underground hydrogen storage (UHS) in Taranaki, ANZ. Here, we explore the potential for UHS in porous rock formations of depleted gas reservoirs with particular focus on the role of seal integrity for storage. 

In this project the overarching goal is to improve understanding of whether mudstone seal strata have the potential to prevent leakage of hydrogen from Taranaki reservoirs. The primary focus is to characterise the geometries of fault and fracture systems in seal strata, their impact on its bulk permeability and to identify the pressure conditions required to promote the loss of seal integrity. In this poster we use Formation Micro Imagery (FMI) together with stratigraphic and fault/fracture mapping of core from petroleum wells to identify fracture densities, orientations and properties in both seal and reservoir rocks. Interpretations of seismic reflection lines in Taranaki and analogous outcrop observations are used to understand the geometries and permeability properties of fault zones. 

Preliminary results indicate that fractures are present in both reservoir and seal rocks. The densities of fractures increase with proximity to regional fold hinges and faults, and with increasing carbonate content. Questions remain about under what conditions fractures are open and capable of transmitting hydrogen. The poster outlines preliminary results, proposed research pathways and invites discussion.
Carbonate Mineralization Related to Weathering of Mafic and Ultramafic Rocks in the Pali Aike Volcanic Field, Extra-Andean Patagonia, Chile
Authors: Henriquez Carolina , Calderon Nettle Mauricio , Cury Leonardo , Quezada Paulo , Bahniuk Anelize
Published: March 2024

On geological timescales, the volume of CO2 in the atmosphere is influenced by processes such as silicate weathering. In particular, the weathering of basaltic rocks increase the availability of divalent cations such as Mg2+ and Ca2+ in natural waters enabling carbonate formation under atmospheric conditions. Therefore, the existence of carbonate deposits in basaltic provinces provides an excellent opportunity to contribute for the regional environmental record. The Pali Aike Volcanic Field consist of basaltic rocks that covers an area of ca. 4500 km2 in southernmost South America, which were sourced from a deep Mantle source since ca. 4 Ma until the Holocene. The Laguna Timone is a maar filled by a brine developed after explosive volcanic eruptions and constitutes an endorheic hydrological system where carbonate precipitation (calcite and magnesium calcite) is controlled by enrichment of Ca2+ and Mg2+ ions released during the weathering of alkaline basalts. X- ray fluorescence analyses in basaltic rocks reveal high concentration of elements such as CaO (9.73 - 10.57 wt.%) and MgO (9.49-12.76 wt.%).  X-ray diffraction results verify that basalts contain pyroxene (Na, Ca) (Mg, Fe, Al) (Al, Si)2O6, olivine (Fe, Mg)2SiO4 and plagioclase NaAlSi3O8-CaAl2Si2O8 which are suitable phases for the mineral carbonation process. The δ13C DIC values of lake range between −12‰ and −16‰ while for the water of the river values of -7‰. These isotopic ratios are associated to three possible sources/processes: weathering of silicates by carbonic acid, atmospheric CO2 and degradation of organic matter. Furthermore, Sr isotope ratios of carbonates (tufa fragments and thin crust in pebbles) define a range between 0.70408 and 0.70475 which is discussed on basis of the data of basaltic rocks (0.70316 to 0.70351) and top soils (0.705382) in the PAVF. Although the Sr isotope ratios of carbonates are indicative of their derivation from the weathering of basalts an exogenous input from relatively enriched 87Sr material is required, this could be associated to 87Sr leached from the top soils and transported by strong wind. Contrastingly a carbonate vein preserved in the tuff ring deposit of the maar has Sr isotope ratios ranging from 0.70265 to 0.70314, similar to the compositional range of the Mantle xenoliths (0.70264 to 0.70431) and basalts. These data indicate that primary sources of carbonates in the lake are related to in-situ weathering of mafic and ultramafic rocks.
Influence of Geochemical Features on Elastic and Fracture Behavior of Organic Matter
Authors: Zhao Junliang , Zhang Pengyu , Zhang Wei , Zhang Dongxiao
Published: March 2024

As the source material of hydrocarbon and a significant matrix constituent in organic-rich shale, organic matter influences not only the oil/gas generation and accumulation but also the mechanical behavior of shale formations. Previous researches have found that organic matter exhibits different mechanical properties from inorganic minerals, and proved that geochemical features could significantly affect the elastic behavior of organic matter in shale. Here, this work systematically investigates the influence of organic type and/or thermal maturation on mechanical behavior of organic matter. For elastic behavior, in conjunction with vitrinite reflection test, scanning electron microscope (SEM) observation, and micro-Raman analysis, nanoindentation is performed to measure the modulus of different macerals. The results indicate that with the same thermal maturity, inertinite has the highest Young’s modulus, while the modulus of bitumen is the lowest. In addition, with the increase of thermal maturity, the Young’s moduli of all kinds of maceral tend to increase, while the intensity ratio of D peak to G peak measured by micro-Raman analysis shows a decreasing trend, which indicates a higher degree of graphitization. For fracture behavior, maceral identification, focused xenon ion beam fabrication, and in situ fracture test are combined to analyze the deforming and fracturing process of different organic types. Micro cantilever beams are manufactured by using a xenon plasma focused ion beam-SEM (Xe PFIB-SEM), and then loaded in an environmental SEM (ESEM). Organic matter particle is set at the fixed end of cantilever beam, and the load is applied at the free end. Thus, the interaction between micro crack and organic matter can be observed and the corresponding mechanical data can be recorded. Test results indicate that the micro cantilever beams dominated by inertinite and vitrinite show the features of brittle failure, while those dominated by bitumen show the features of ductile failure. These microscale findings can support the upscaling model for precise prediction of mechanical properties at the macro scale, and assist with the understanding and interpretation of macroscopic elastic and fracture behavior in shale reservoirs.
A model for representing earth observation tasks that supports the dynamic demand for flood disaster monitoring and management
Authors: Zhao Zhongguo , Hu Chuli , Wang Ke , Zhang Yixiao , Xu Zhangyan , Ding Xuan
Published: March 2024

A comprehensive, accurate, and timely expression of earth observation (EO) tasks is the primary prerequisite for responding to emergency monitoring of disasters, especially floods. However, the existing information model does not fully satisfy the demand for a fine-grain observation expression of EO task, which results in the absence of task process management. The current study proposed an EO task representation model based on meta-object facility to address this problem. The model not only describes the static information of a task, but it also defines the dynamics of an observation task by introducing a functional metamodel. This metamodel describes the full life cycle of a task; it comprises five process methods: birth, separation, combination, updating, and extinction. An earth observation task modeling and management prototype system (EO-TMMS) for conducting a remote sensing satellite sensor observation task representation experiment on flooding was developed. In accordance with the results, the proposed model can describe various EO tasks demands, full life cycle process of EO task. Compared with other typical observation tasks information models, the proposed model satisfies the dynamic and fine-grain process representation of EO tasks, which can improve the efficiency of EO sensors utilization
Accelerating Geoscience Research: An Advanced Platform for Efficient Multimodal Data Integration from Geoscience Literature
Authors: Guo Zhixin , Zhou Jianping , Zheng Guanjie , Wang Xinbing , Zhou Chenghu
Published: March 2024

In the era of big data science, geoscience has experienced a significant paradigm shift, moving towards a data-driven approach to scientific discovery. This shift, however, presents a considerable challenge due to the plethora of geoscience data scattered across various sources. These challenges encompass data collection and collation and the intricate database construction process. Addressing this issue, we introduce a comprehensive, publicly accessible platform designed to facilitate extracting multimodal data from geoscience literature, encompassing text, visual, and tabular formats. Furthermore, our platform streamlines the search for targeted data and enables effective knowledge fusion. A distinctive feature of it is its capability to enhance the generalizability of Deep-Time Digital Earth data processing. It achieves this by customizing standardized target data and keyword mapping vocabularies for each specific domain. This innovative approach successfully overcomes the constraints typically imposed by a need for domain-specific knowledge in data processing. The platform has been effectively applied in processing diverse data sets, including mountain disaster data, global orogenic belt isotope data, and environmental pollutant data. This has facilitated substantial academic research, evidenced by developing knowledge graphs based on mountain disaster data, establishing a global Sm-Nd isotope database, and meticulous detection and analysis of environmental pollutants. The utility of our platform is further enhanced by its sophisticated network of models, which offer a cohesive multimodal understanding of text, images, and tabular data. This functionality empowers researchers to curate and regularly update their databases meticulously with enhanced efficiency. To demonstrate the platform's practical application, we highlight a case study involving compiling Sm-Nd isotope data to create a specialized database and subsequent geographic analysis. The compilation process in this scenario is comprehensive, encompassing tasks such as PDF pre-processing, recognition of target elements, human-in-the-loop annotation, and integrating multimodal knowledge. The results obtained consistently mirror patterns found in manually compiled data, thereby reinforcing the reliability and accuracy of our automated data processing tool. As a core component of the Deep-Time Digital Earth (DDE) program, our platform has significantly contributed to the field, supporting forty geoscience research teams in their endeavors and processing over 40,000 documents. This accomplishment underscores the platform's capacity for handling large-scale data and its pivotal role in advancing geoscience research in the age of big data.
High-resolution Assessment of Heat Mitigation Strategies in the City of Toronto
Authors: Hesse Sara , Krayenhoff Scott , Jiang Timothy , Lu Henry , Gaur Abhishek
Published: March 2024

Toronto is vulnerable to the negative impacts of extreme heat episodes, due to its high density of buildings, regular summertime heat episodes, and complex weather patterns influenced by Lake Ontario. As warming trends are anticipated to continue, the number of extreme heat days (warmer than 30 OC) will also increase. A high frequency of extreme heat days is associated with increased heat related mortality. Despite this, studies assessing strategies of heat mitigation in Toronto, which involve implementing infrastructure to reduce heat hazards, are currently limited. Using the mesoscale (~ 1 km resolution) climate model, Weather Research and Forecasting (WRF), various heat mitigation strategies, including addition of vegetation and high albedo surfaces, are explored. To quantify the impacts of urbanization, we modelled climatic conditions in the Toronto region with and without urban development. This step established that under the same boundary conditions, the presence of urban features significantly increases diurnally averaged temperatures in Toronto by as much as 4 oC. Having established that urbanization has led to higher temperatures, we then modelled the impacts of adding cool roofs and vegetation to urbanized Toronto simulations, finding that having 80% vegetation in all grid cells significantly reduces day-time diurnal temperatures. Lastly, our project will include a novel addition of street trees into WRF, allowing users to calculate tree-building interactions, including evapotranspiration and radiation trapping effects. The results of this study will be used in real time by building simulation teams to determine which mitigation strategies will best prevent overheating.
Flow Channeling, Dissolutional Growth, and Preferential Flow of Fractures in Karst formation: Insights from Reactive Transport Modeling
Authors: Liu Haocheng , Dong Chunmei , Lin Chengyan
Published: March 2024

Fractured and karstified carbonates often serve as major aquifers and hydrocarbon reservoirs. Water-rock interactions within variable aperture fractures can lead to dissolution of fracture surfaces and local alteration of fracture apertures, potentially transforming the transport properties of fractures over time. Numerical modeling offers a valuable tool for comprehending the spatial and temporal evolution of karst reservoirs. This work aims to present a comprehensive model to reveal percolation characteristic and dissolution process of stochastic primary fracture systems in carbonate formation. Based on the embedded discrete fracture model, a multi-scale modeling approach is proposed to describe fracture networks with different topologies and various apertures. This model is verified against preexisting numerical models. Simulation results shows that the mechanisms of flow focusing and reactive infiltration instabilities determines fracture dissolutional propagation. Patterns of local dissolution-induced alterations related to fracture permeability, hydraulic conductivity and extensive dissolution appear in fracture tips and intersections.
Modeling the Influence of Subsurface Geology on Northern Peatland Hydrology
Authors: Niedzinski Victoria , Reeve Andrew , Slater Lee , Comas Xavier
Published: March 2024

Peatlands are complex wetlands that play an important role in global carbon cycling as both carbon sinks and sources. They contain over one-third of all global soil carbon but cover
Exploring subsurface heterogeneity of nitrogen and carbon cycling under a southeastern U.S. cattle grazing pasture 
Authors: Roscioli Joseph , Shorter Joanne , Lunny Elizabeth , Herndon Scott , Gomez-Casanovas Nuria , Byck Peter
Published: March 2024

Subsurface cycling of nitrogen and carbon is central to our understanding of biosphere-atmosphere exchange and can strongly impact the ability of soil to be a greenhouse gas source or sink.  The underlying processes exhibit strong environmental dependence that can lead to substantial spatiotemporal heterogeneity across scales.  Here we present a study that explores how that variability manifests in subsurface greenhouse gases and their isotopes under a cattle grazing pasture in the southeastern U.S.  We used an automated array of 24 diffusive soil gas probes connected to a tunable infrared laser direct absorption spectrometer (TILDAS) to produce real-time maps of nitrous oxide isotopes, carbon dioxide, and oxygen with high spatial (meters) and temporal (hours) resolution.  We discuss ways to visualize and process the heterogeneity data, including using Lorenz plots and two-dimensional correlation, to reveal the magnitude and persistence of spatial heterogeneity of these gases.  CO2 is found to be much more spatially homogeneous than N2O, indicating a stronger dependence of N processing upon the local environment.  Analysis of N2O isotopic signatures shows that the last step in subsurface N-cycling, N2O reduction, is spatially heterogeneous and related to the magnitude of “hot spots” of N2O production.   
Soil microbial communities undergo changes in various succession stages following a wildfire in an alpine forest
Authors: Cheng Hao
Published: March 2024

Wildfires are the typical ecological disturbances to forests globally, vegetation regeneration and successional routes may be altered, changing coniferous forests into broad-leaved forests, shrublands, or grasslands. As soil microbes mediate soil function and different biogeochemical cycles, taking into account the effects of disturbance on soil microbes is essential. However, little is known about the response of the soil microbial community to this succession, especially in alpine forest ecosystems. Here, we studied the differences between soil bacterial communities of three different vegetation succession in an alpine forest ecosystem after wildfire and compared them to a control unburned soil. The results showed that there were significant differences in soil properties of vegetation successional after wildfire. Compared to coniferous forests and broad-leaved forest soil plots, shrubland soil plots had higher pH (4.02±0.02); SOC and TN had no significant differences, but broad-leaved forest soil plots had higher TP (1.36±0.08). Compared to burned soil plots, the unburned soil plots had higher SOC (101.32±7.70), TN (6.02±0.29), and N:P (6.66±0.54). Vegetation successional after wildfire significantly changed the Shannon, chao1, pielou, and Simpson diversity index of soil bacterial community. Compared to unburned soil plots, the relative abundance of Acidobacteria decreased by 16.53%, 5.57%, and 5.13% in shrublands, coniferous forests, and broad-leaved forests, respectively. While the relative abundances of Actinobacteria increased by 4.53% in coniferous forest soil plots, the relative abundances of Chloroflexi increased by 10.93% and 6.87% in shrublands soil plots and broad-leaved forest soil plots, respectively. Principal coordinates analysis (PCoA) analysis indicated that the similarity of soil bacterial communities was higher in different succession after wildfire. We found soil bacterial communities significantly influenced by elevation (r2=0.86, p=0.0005), pH (r2=0.46, p=0.0005), and C: N (r2=0.45, p=0.0015). This study provides a better understanding of the correlation between soil microbial communities and the function of alpine forest ecosystems after wildfires.
Lithospheric Imaging of Northern Taiwan Using Teleseismic Full Waveform Inversion: from Volcanic Reservoirs to Plate Boundaries
Authors: Kan Li-Yu , Kuo-Chen Hao , Chevrot Sebastien , Sibuet Jean-Claude , Lin Cheng-Horng , Monteiller Vadim
Published: March 2024

The tectonic of northern Taiwan is in a post-collisional stage and has undergone a subduction polarity flip between the Eurasian Plate (EP) and Philippine Sea Plate (PSP). The shallow crust of northern Taiwan features the Tatun Volcano Group (TVG) and the Turtle Island magma reservoirs, with their proximity to Taipei metropols highlighting the volcanic risks to densely populated regions and critical infrastructure. However, it is challenging to image all these structures from the surface down to several hundred kilometers depth with classical passive tomographic approaches. Here, we present tomographic models of density, P-wave velocity (Vp), S-wave velocity (Vs), and the Vp/Vs ratio beneath northern Taiwan, obtained by inverting complete teleseismic waveforms from 18 P and 9 SH events recorded by 175 broadband stations from the Formosa Array and the permanent stations. In our final model, the plate boundary between EP and PSP is clearly depicted as a west-dipping plane, consistent with the western boundary of slab seismicities. Our model identifies two distinct low-velocity, high VP/VS bodies beneath the TVG and Turtle Island, indicative of underlying magma reservoirs. The reservoir beneath the TVG is beaker-shaped, extending from a depth of 6 to 20 kilometers. The reservoir beneath Turtle Island, located on the island’s eastern side, is larger than TVG's but less well defined due to sparse station coverage. The crust north of the Hsueshan Range is thinner, likely related to the post-collisional delamination of the lower crust. This process leads to increased mantle heat flow, providing the heat source for the TVG. With the new 3-D model, we also relocate the local events by utilizing a nonlinear location method, in order to improve their spatial accuracy and get better constraints on the seismogenic structure.
Resilient Waters: Exploring Hydrological Response in Evolving Mountain Systems of the Southern Andes
Authors: Somos-Valenzuela Marcelo , Morales Bastian , Lizama Elizabet , Lillo Mario , Fernandez Alfonso , Rivera Diego
Published: March 2024

Mountain systems have experienced significant changes due to variations in precipitation and temperature. These changes have affected natural water reservoirs, such as glaciers and snow. There is a high probability that glaciers will disappear entirely in some mountain ranges during this century, with current impacts evident on the flows and ecosystems dependent on them. The reduction in snow cover has also been observed globally, especially in lower altitude areas, due to the increase in liquid rain. The increase in temperature has accelerated the melting of snow before the season of most significant water demand. This transformation in mountain basin hydrology raises global concerns about the sustainability of water resources.Despite the evident loss of storage in glaciers and snow, numerous studies have highlighted the importance of mountain aquifers, quaternary deposits, wetlands, and fractured basements in groundwater storage. However, these elements are often ignored in studies that project changes in flow in mountainous areas.Mountain catchments will play a crucial role in the response of Earth systems to climate change. Given the loss of glaciers and decreases in solid precipitation, these systems will activate alternative mechanisms to provide water in times of less rainfall, acting as hydrological refuges. Identifying these refuges is crucial for the conservation and management of watersheds.Although there are studies on climate change refugia for species habitat, there is no defined conceptual framework for hydrological refugia in the Southern Andes of Chile. This work seeks to review elements within the basins that could mitigate or delay the effects of climate change on flows, proposing indexes to identify potential refuges and validate their usefulness in multiple basins throughout the Southern Andes of Chile.
Estimating Climate Sensitivity from UV satellite observations and CMIP6 models since 198
Authors: Weaver Clark , Wu Dong , Labow Gordon , Haffner David , Borgia Lauren , McBride Laura , Salawitch Ross
Published: March 2024

We construct a long-term record of Top of Atmosphere shortwave (SW) albedo of clouds and aerosols from 340 nm radiances observed by NASA and NOAA satellite instruments from 1980 to 2013. We compare our SW cloud+aerosol albedo with simulated cloud albedo from both AMIP and historical CMIP6 simulations from 47 climate models. While most historical runs did not simulate our observed spatial pattern of the trends in albedo over the Pacific Ocean, four models qualitatively simulate our observed patterns. Those historical models and the AMIP models collectively estimate an Equilibrium Climate Sensitivity (ECS) of ~3.5oC, with an uncertainty from 2.7 to 5.1oC. Our ECS estimates are sensitive to the instrument calibration which drives the wide range in ECS uncertainty. We force the calibrations to have a near neutral change in reflectivity over the Antarctic ice sheet. Our observations show no sign of dissipating marine stratocumulus clouds. Instead, they show increasing cloudiness over the eastern equatorial Pacific and off the coast of Peru as well as neutral cloud trends off the coast of Namibia and California. To produce our SW cloud+aerosol albedo we first retrieve a Black-sky Cloud Albedo and empirically correct the sampling bias from diurnal variations. Then we estimate the broadband proxy albedo using multiple non-linear regression along with several years of CERES cloud albedo to obtain the regression coefficients. We validate our product against CERES data from the years not used in the regression. Zonal mean trends of our SW cloud+aerosol albedo show reasonable agreement with CERES as well as the Extended Pathfinder Atmospheres (Patmos-x) observational dataset.
The impact of streamflow forecast errors on economic outcomes in future climates
Authors: Modi Parthkumar , Carbone Jared , Kamen Hannah , Small Eric , Szafranski Bill , Wobus Cameron , Livneh Ben
Published: March 2024

More than half of annual runoff across the montane regions of the western US and Europe originates as snowmelt, making knowledge of snowpack crucial to the quality of water supply forecasts. However, ongoing and projected warming is expected to reduce snow water equivalent (SWE) and alter snowmelt timing, thus impacting forecast skill and uncertainty. Rising temperatures are anticipated to reduce the fraction of future precipitation falling as snow by up to 30% in intermountain and continental regions of the western US. This will fundamentally alter the regional water cycle, and we posit that this will increase forecast errors and uncertainty, ultimately impacting the quality of decision-making that relies on water supply information. This research assesses the Relative Economic Value (REV) of water supply forecasts under changing snowpack regimes to understand the impact of forecast uncertainty on economic outcomes. Forecast errors will be rigorously estimated using statistical, physical, and machine learning models applied to 76 western US basins. Historical and projected future hydrology (2025-2050) will serve as a test bed for the analysis. Preliminary results over these basins suggest forecast errors on the order of +/- 25%, corresponding with changes in economic outcomes of up to +/- 15%. With findings from the proposed research, we hope to aid water entities by assessing the economic outcomes based on the skill of water supply forecasts, thereby exploring how forecast users can maximize productivity in response to changing climate conditions.
The NOAA Balloon Baseline Stratospheric Aerosol Profiles (B2SAP) – In situ insight on the stratospheric aerosol layer 
Authors: Baron Alexandre , Asher Elizabeth , Smith Katie , Thornberry Troy ,   B2SAP extended Team
Published: March 2024

Stratospheric aerosols play a crucial role in the climate system, but uncertainties persist in understanding the chemical, dynamical, and microphysical processes governing their distribution and variability. The chemical and radiative impacts of stratospheric aerosols hinge on particle size distribution. However, models exhibit significant variations in how they parameterize aerosol microphysical processes and simulate size distributions, leading to divergent predictions of the time evolution of radiative impacts from stratospheric aerosol perturbation events. To refine models for assessing the effects of potential climate intervention strategies, systematic measurements are crucial. In pursuit of this understanding, the Baseline Balloon Stratospheric Aerosol Profiles (B2SAP) project utilizes compact, lightweight payloads carried by meteorological balloons. These payloads measure aerosol number density and size distributions, along with water vapor, ozone, and meteorological data from the surface to the middle stratosphere. The long-term goal of the B2SAP project is to generate climatologies of aerosol number and size distributions up to the middle stratosphere at latitudinally distributed measurement sites. Since March 2019, B2SAP payloads have been launched from Boulder, CO, USA (40°N) once to twice per month and four to six times per year from Lauder, NZ (45°S). Starting in 2022, two tropical sites were added to this evanescent network with quarterly launches: Hilo, HI, USA (20°N) and Reunion Island, FR (20°S). These measurements provide a new record of in situ observations allowing to characterize the natural stratospheric aerosol burden, its variability, and responses to perturbations, providing essential data for refining models and aiding in the validation of satellite-based estimates. In this context, we will present a subset of this growing database, emphasizing the discussion on the stratospheric aerosol layers in the North hemisphere and South hemisphere (SH) mid-latitudes. Perturbations recorded in the SH after the Australian New Year super pyroCb outbreak in 2020 will also be investigated.
US fossil-CO2 emissions from 2010 - 2019 based on measurements of atmospheric radiocarbon
Authors: Miller John , Islam Nazrul , Lehman Scott , Basu Sourish , Andrews Arlyn , Sweeney Colm , Tans Pieter , Xu Xiaomei , Gurney Kevin
Published: March 2024

Despite inventory-based (“bottom-up”) estimates of fossil-fuel emissions likely being accurate to within 10% for most developed countries, estimates of emissions based on atmospheric measurements are needed to bolster confidence in bottom-up estimates as well as possibly reduce uncertainty and provide emissions estimates closer to real time.  In the case of CO2, however, measurements of CO2 concentrations alone, whether from in situ or remote sensing approaches, are not sufficient to determine fossil emissions because of the confounding influence of terrestrial ecosystem CO2 exchange which influences, and even dominate, spatio-temporal gradients of CO2.  The rarest isotope of C, 14C (radiocarbon), is completely absent from fossil CO2 because of radioactive decay allowing us to use precise measurements of atmospheric CO2 and its 14C:C ratio to isolate the fossil contribution to observed gradients.  Within the context of an atmospheric inverse model, CO2 and 14C:C measurements provide constraints that yield optimized fluxes of both fossil and ecosystem CO2.  Using a global, but US-focused, radiocarbon measurement and modeling system developed over the past 20 years, we are now able to estimate seasonal fossil CO2 emissions for different regions the U.S. between 2010 and 2019 with an estimated national, annual random error of ~ 2%.   Our top-down estimates for 2010 and 2015 show a significant decrease in US fossil CO2 emissions in line with, yet independent from, the inventory-based estimates from the US EPA.  Despite some limitations of top-down emissions related to systematic errors in atmospheric transport models, we expect that top-down year to year flux changes should be robust with respect to transport error, as has been shown previously in model intercomparison studies.  Indeed, while our 2015 – 2010 decrease matches the EPA well, mean emissions are offset, although within 95% confidence intervals. Spatially, our results show that the eastern third of the US dominates national emissions and also dominates the observed decrease, consistent with the understanding that US emissions have decreased since their peak mainly as a result of a transition from coal- to gas-fired power plants, which are dominantly in this area.  Here, we will compare our 2010-2019 emissions estimates with both the EPA’s official US inventory and other bottom-up estimates such as the Vulcan data product that were not used as a priori information in our inverse modeling system.  We will also discuss the steps required to enhance our US-focused system and the extent to which our system might be applied to regions in other parts of the world.
Basin management inspiration from impacts of alternating dry and wet conditions on water production and carbon uptake in arid region
Authors: Lu Zhixiang , Feng Qi , Xie Jiali
Published: March 2024

The impacts of alternating dry and wet conditions on water production and carbon uptake at different scales remain unclear, which limits the integrated management of water and carbon. We quantified the response of runoff efficiency (RE) and plant water-use efficiency (PWUE) to a typical shift from dry to wet episode of 2003–2014 in Australia's Murray-Darling basin using good and specific data products for local application, including Australian Water Availability Project, Penman-Monteith-Leuning Evapotranspiration V2 product, MODIS MCD12Q1 V6 Land Cover Type and MODIS MOD17A3 V055 GPP product. The results show that there are significant power function relationships between RE and precipitation for basin and all ecosystems, while the PWUE had a negative quadratic correlation with precipitation and satisfied the significance levels of 0.05 for basin and the ecosystems except the grassland and cropland. The shrubs can achieve the best water production and carbon uptake under dry conditions, while the evergreen broadleaf trees and evergreen needleleaf trees can obtain the best water production and carbon uptake in wet conditions, respectively. These findings help integrated basin management for balancing water resource production and climate change mitigation.
Groundwater quality assessment for human consumption. A case study of the Middle Magdalena Valley  – Colombia.
Authors: Lora-Ariza Boris , Piña Adriana , Donado Leonardo David , Vaca Mónica
Published: March 2024

Water quality is one of the major causes affecting human health, especially in vulnerable populations in developing countries. In Colombia, groundwater is often consumed by rural populations as drinking water without any treatment. Therefore, a groundwater quality assessment in the Middle Magdalena Valley in Colombia (MMV) was conducted to determine potential health hazards associated with its consumption. The study area covers approximately 8500 km2 and is bounded by the piedmont of the San Lucas Mountain range and the Central and Eastern Mountain Ranges of the Andes.In this study, 458 water samples were analyzed. They were collected during three (3) field campaigns conducted between February 2020 and March 2021, encompassing contrasting hydrologic periods. Based on laboratory results, the potential health hazards associated with groundwater consumption were assessed using the Colombian Water Quality Risk Index (CDQRI-IRCA).CDQRI-IRCA values in the MMV ranged from 0 to 80, with a mean of 51 and a standard deviation of 21. Furthermore, more than 84% of the analyzed samples were classified as high risk for human consumption. This outcome is associated with the presence of fecal and total coliforms in 58% and 89% of the analyzed samples, respectively. These parameters hold the highest specific weights in the CDQRI-IRCA calculation.The presence of fecal and total coliforms in groundwater in the MMV is associated with deficiencies in sanitation coverage, particularly in rural areas where water supply wells are often located near septic tanks, handmade pit latrines without proper hygienic protection, or in areas with backyard livestock farming. AcknowledgmentsThe researcher thanks the MEGIA Research Project, Contingent Recovery Contract FP44842-157-2018 funded by Minciencias and the National Hydrocarbons Agency 
Removal of strontium and cesium from soil using ion-based washing agents with similar hydrated radii
Authors: Song Hojae , Shim Gunwoo , Nam Kyoungphile
Published: March 2024

The environmental hazards associated with nuclear power plants, specifically the release of fission byproducts such as strontium (Sr) and cesium (Cs) are highlighted for their harmful attributes, even in non-radioactive forms owing to their physicochemical characteristics and potential health risks. Sr and Cs exhibit significant physicochemical resemblances to calcium (Ca) and potassium (K), respectively. These similarities are so pronounced that the human body often confuses Sr and Cs with Ca and K, leading to their accumulation. This accumulation can give rise to detrimental health conditions, including leukemia, thyroid cancer, bone marrow cancer, and general paralysis. In this study, a soil washing method was employed to eliminate Sr and Cs contaminants from the soil. We hypothesize that the efficiency of Sr and Cs removal is influenced by the resemblance in physicochemical properties. Physicochemical properties such as atomic radius, hydrated radius, electronegativity, and electron affinity of Sr, Cs, Na, Mg, K, Ca, Ba, and Al were carefully studied and summarized for the investigation. Subsequently, solutions with Na, Mg, K, Ca, Ba, and Al at concentrations of 0.1 and 0.01 M, with a pH of 7, were tested for their efficacy in removing Sr and Cs from the soil. The results showed that the greater similarity in hydrated radius between heavy metals and ions appears to be responsible for increased removal efficiencies. For example, both Ca and Sr share the same hydrated radius of 0.412 nm. Interestingly, Ca exhibited the highest efficiency in removing Sr compared to Na, K, Mg, Ba, and Al. Additionally, Ba, with a hydrated radius of 0.404 (the second closest to Sr), demonstrated the second-highest efficiency in Sr removal. Examining results for other heavy metals (i.e., Cd, Co, Cu, Ni, Pb, and Zn), a heightened resemblance in hydrated radii between the heavy metal and ion corresponded to increased removal efficiency, indicating a strong positive correlation. Overall, this study contributes valuable insights into effective strategies for mitigating the environmental impact of nuclear power plant activities on soil contamination.
Measurement of the Total Meltwater Amount in the Greenland Ice Sheet Using SMAP L-band Radiometry 
Authors: Hossan Alamgir , Colliander Andreas , Miller Julie , Marshall Shawn , Harper Joel , Vandecrux Baptiste
Published: March 2024

With the growing concern of climate change, an accurate estimation of the total meltwater amounts (MWA) in the Greenland ice sheet (GIS) becomes crucial for understanding the physical processes of the GrIS and its mass balance, thereby enabling accurate prediction of its contribution to the global sea-level rise. Satellite microwave radiometers have been widely used for monitoring ice sheet melting for the last four decades; nevertheless, quantification of total MWA, especially the sub-surface MWA, remains a challenge.Here, we used the enhanced resolution L-band brightness temperature (TB) observations from the NASA Soil Moisture Active Passive (SMAP) mission to quantify the magnitude of the total MWA in GrIS for 2015-2023. Because of the larger penetration depth, L-band signals can track liquid water in deeper layers and provide a reliable estimate of surface-to-subsurface MWA, contrary to the higher frequency signals (18 or 37 GHz bands), which are limited to the top few centimeters of the surface snow. The algorithm uses vertically polarized (V-pol) TBs and an empirically derived adaptive thresholding technique to detect melt events. A simple microwave emission model, based on ice sheet radiative transfer, was used to simulate L-band TBs. The simulated TBs were then used in an inversion algorithm for MWA retrieval.Finally, the retrieval was compared with the corresponding MWA derived from an ice sheet energy and mass balance (EMB) model which was forced by hourly in situ observations from the Programme for Monitoring of the Greenland Ice Sheet (PROMICE) automatic weather station (AWS) network. The model was initialized and constrained by the relevant ice core density and sub-surface temperature profiles. The retrievals generally demonstrate a stronger agreement with the in situ observations in the percolation zone than in the ablation and upper elevation regions. The radiometric sensitivity, meltwater process, and their spatiotemporal variability were analyzed. The results demonstrate the potential for advancing our understanding of ice sheet physical processes to better project Greenland’s contribution to global sea level rise in response to the warming climate.
Development of coastal groundwater management solution in Jeju Island, South Korea
Authors: Chung IL Moon , Chang Sun Woo , Woo So Young
Published: March 2024

Jeju Island is the region in South Korea that receives the highest amount of rainfall, and most of this precipitation infiltrates into the ground as groundwater, which is utilized as the primary water resource. The major challenge in extracting groundwater in coastal areas is the intrusion of seawater. This study aims to develop management solutions to address the limitations on water resource utilization and water scarcity issues caused by saltwater intrusion in coastal areas. Utilizing observational data from Jeju, precise water circulation analysis and hydrogeological data related to groundwater salinization were collected. The study also involved the construction of a database for hydrological components based on water circulation analysis and the impacts of climate change. Additionally, techniques for predicting coastal groundwater levels and developing a coastal groundwater management system were established. Through the research findings, it is expected that a comprehensive solution for coastal groundwater management in response to climate change, improved accuracy in groundwater level management, and policy recommendations can be achieved. Acknowledgment : The work was suppored by the KICT Research Program (project no. 20230166-001, Development of Coastal Groundwater Management Solution) funded by the Ministry of Science and ICT. 
Detection of iodine oxide by Broadband Cavity-Enhanced Absorption Spectroscopy (BBCEAS) based on an ICAD (iterative cavity-enhanced DOAS) algorithm
Authors: Qin Min , Xie Jianye , Han Baobin , Fang Wu , Zhang Helu , Shao Dou , Ren Enbo , Zhao Xiadan , Liao Zhitang , Duan Jun , Xie Pinhua
Published: March 2024

Correspondence: Min Qin (mqin@aiofm.ac.cn)Abstract: Iodine oxide (IO) radicals, as a significant active halogen species in the iodine cycle, play a crucial role in the ozone depletion process. They affect atmospheric chemistry by altering the distribution of NO/NO2 and OH/HO2 radicals. In coastal regions, IO radical play an important role in the formation of ultrafine aerosol particles. The nucleation of these particles affects cloud properties, thereby impacting the climate.Therefore, for the monitoring and understanding of its tropospheric chemical processes, it is important to explore and develop new techniques for the sensitive measurement of IO. Here, the quantitative method for detection atmospheric IO radicals using Broadband Cavity-Enhanced Absorption Spectroscopy (BBCEAS) technique was introduced. Considering the spectral absorption characteristics of IO radicals in the 435 - 465 nm wavelength region, as well as the actual atmospheric levels in the marine boundary layer, the parameters which affected the BBCEAS system performance were investigated. An iterative algorithm (ICAD) which actually models the light path reduction from the derived absorbers in the optical resonator applied to BBCEAS technique was established. Constant IO concentration used to evaluate the IO sampling loss was generated from the photolysis of molecular iodine (I2) and then reacting with ozone (O3). Nitrogen was bubbled through a solution of I2 and potassium iodide (KI) to take out I2 and then diluted before the reaction between iodine (I) and O3 occurring. The loss of IO within a 10-meter sampling tube was estimated to be approximately 2%, which can be neglected. The system's performance was assessed using Allan variance. For an acquisition time of 60 s, 2σ detection limits for IO and NO2 were about 1.9 pptv and 20 pptv, respectively. The dependency between IO radicals generated from the photolysis of iodine emitted by seaweed and seaweed activity was investigated in the laboratory. The peak of IO radicals reached a maximum value of 50 pptv with O3 at ppmv level, and subsequently the IO radicals showed a declining trend with the reduction of seaweed activity.Acknowledgements: This work was supported by the National Key Research and Development Program of China (Grant No. 2022YFC3700300) and the HFIPS Director’s Fund (Grant No. YZJJQY202205). 
APEP: Eclipse Sounding Rocket Campaign
Authors: Barjatya Aroh , Clayton Robert , Debchoudhury Shantanab , Zettergren Matthew , Valentine Henry , Graves Nathan , Conway Rachel , Ribbens Peter , Milford Joshua , Obenberger Kenneth , Holmes Jeffrey , Chau Jorge (Koki) , Lynch Kristina , Mrak Sebastijan , Bullett Terry
Published: March 2024

Solar eclipses present a unique opportunity to study the effects of a supersonic cooling shadow and its modulation of the structure and energetics of the ionosphere-thermosphere system. Atmospheric Perturbations around Eclipse Path (APEP) is an eclipse rocket campaign that launched 3 sounding rockets from White Sands Missile Range (WSMR) during the Oct 2023 annular eclipse and will launch 3 sounding rockets from the Wallops Flight Facility (WFF) during the April 2024 total solar eclipse. This campaign will be the first simultaneous multipoint spatio-temporal in-situ observations of electrodynamics and neutral dynamics associated with solar eclipses. For each eclipse, the first instrumented rocket will be launched ~35 minutes before peak local eclipse, second at peak local eclipse, third ~35 minutes after peak local eclipse. The launches are supported by ground-based observations from AFRL Digisondes for WSMR launch and by VIPIR Dynasonde and Millstone ISR for WFF launch. Ground based meteor radar observations of neutral winds are also performed for both eclipses. These observations will be used to constrain comprehensive modeling during data analysis. 