bluuebunny/crossref_metadata_2025 huggingface dataset:
Pedodiversity, biodiversity, and SOC storage in an alpine pasture
Authors: Ferré Chiara , Mascetti Gaia , Agaba Sara , Fuccella Roberto , Gentili Rodolfo , Comolli Roberto
Published: February 2023

Mountain soils provide a variety of ecosystem services (ES) that are increasingly threatened by anthropogenic impacts and climate change.We present here the results of a study on the pedodiversity, biodiversity, and soil organic carbon (SOC) sequestration of alpine soils in a pasture of the central Alps, that took into account the effect of morphology and vegetation. The study area was the Andossi plateau (350 ha) in Valchiavenna (Lombardy Region), between 1800 and 2000 m elevation.As part of the PascolAndo project, whose goal was to promote sustainable pasture management, at 160 georeferenced points we characterized soils (down to bedrock or a maximum of 50 cm) and carried out the floristic survey to define the vegetation type; soil samples were collected by horizons and analyzed for the main soil properties.The main soil types were Leptosols, Regosols, Cambisols, Umbrisols, Podzols, Gleysols and Histosols, strongly related to geomorphology and vegetation type (peat bogs, earth hummocks, and poor, calcareous, shrub and rich pastures).Histosols and Gleysols of peatland and wet areas showed the highest SOC stock with an average of 31.8±2.6 kg m-2 and 23.3±2.7 kg m-2 respectively, followed by Umbrisols, distributed all over (17.2±6.2 kg m-2), and Podzols (16.6±4.6 kg m-2), typical of poor pastures and shrub areas. The most prevalent soils on the plateau were Cambisols (average SOC stock of 13.6±2.7 kg m-2): Eutric Cambisols were primarily in rich pasture and Dystric Cambisols in poor pasture. Among poorly developed soils, Regosols stored on average 10.8±4.2 kg m-2, while Leptosols, widespread on steep slopes in calcareous pastures and shrub areas, showed the lowest SOC stock (9.6±4.9 kg m-2).Soil types, vegetation types, and SOC were first modeled using geomorphometric variables (27 variables extracted from a 4-m resolution DTM) and vegetation indices (NDVI, NDWI, NDRE, for 3 dates of the growing season, extracted from Sentinel 2 images) and then spatially estimated, allowing quantification of the pedodiversity, biodiversity, and SOC sequestration in the study area.The study showed that the plateau has a high level of biodiversity and pedodiversity, with OC-rich soils that are important for regulating the global climate. There was evidence that grazing and livestock loading affected soil ES by acting on biodiversity, soil fertility, and erosion.
Designing or Upgrading a Seismic Network To Meet Specific Performance Criteria Using Array Modeling, a Case Study
Authors: Laporte Michael , Parker Tim , Hamilton Valarie , McNamara Dan
Published: February 2023

More science, particularly related to hazard reduction and earthquake forecasting, is enabled via the availability of rich seismic datasets and event catalogs. Deployment of high performing monitoring networks, which produce high quality datasets, is an investment that enables ongoing and future science advancements.One measure of network performance, magnitude of completeness (Mc), is determined by a number of factors including station density, network geometry, self-noise and passband of the system used, ambient noise environment and sensor installation method and depth.  Sensor installation techniques related to depth are of particular importance due to their impact on deployment cost and station performance. It is well established that deploying seismic sensors at greater depths reduces their exposure to cultural and environmental noise, improving seismic signal detection. When extended to overall network performance, this noise suppression results in improved (decreased) magnitude of completeness for the network. Using modeling tools, we assess the theoretical improvement in performance associated with an upgrade to borehole installations, increasing sensor depth, for a real world network in the Puget Sound area of Washington State.The goals of monitoring networks and science are overlapping and dependent. Establishing measurable and achievable performance metrics for these supported networks helps the community understand the present distribution of performance and converge on recommendations for government agencies that will benefit both science and monitoring. For example, datasets from monitoring networks with reduced Mc are likely to inform and enable earthquake forecasting research with the potential to benefit hazard reduction for the general population.
French NOx emissions as estimated from TROPOMI-PAL NO2 observations
Authors: Plauchu Robin , Fortems-Cheiney Audrey , Broquet Grégoire , Pison Isabelle , Berchet Antoine , Potier Elise , Coman Adriana , Savas Dilek , Dufour Gaëlle
Published: February 2023

Since 2018, TROPOMI onboard Sentinel-5P has brought images of NO2 tropospheric columns at an unprecedented high spatial resolution. We attempt to exploit the potential of this high-resolution information to estimate NOx emissions at the national scale based on atmospheric inversion approaches, with a 10-km spatial resolution. This study focuses on France and assesses the Covid-19 pandemic effects.Our analysis is based on the variational mode of the recently developed Community Inversion Framework (CIF), coupled with France's configuration of the CHIMERE regional chemistry transport model and its adjoint code. Both CHIMERE and its adjoint code include the MELCHIOR-2 chemical scheme with more than 100 reactions (24 for inorganic chemistry). This variational framework allows to solve high-dimensional inversion problems and thus investigate fine-scale patterns in the concentration and emission fields. It also allows to properly account for the non-linearities associated with the chemistry. CHIMERE is driven by the European Centre for Medium-Range Weather Forecasts (ECMWF) operational meteorological forecast. The inversion corrects anthropogenic emissions from the French National Spatialized Inventory (INS, Inventaire National Spatialisé), mapping NOx emissions at a 1 x 1 km2 horizontal resolution. It also corrects biogenic emissions from the MEGAN model. We use the last TROPOMI reprocessed data: the PAL product. We present different tests that have been conducted to improve the implementation of the observation and control vector in order to strengthen the robustness of the inversion. Then, we evaluate the potential of the TROPOMI-PAL observations to quantify emissions at the national to local scale and at the annual to monthly scale based on the analysis of the reference inversions for the years 2019 and 2020. Finally, we focus on the differences found between the emission estimates for spring 2020 and 2019 to assess the impact of the Covid-19 pandemic.
Predictability of heat waves over West African main cities
Authors: Lavaysse Christophe , Ngoungue Langue Cedric Gacial , Flamant Cyrille , Vrac Mathieu
Published: February 2023

Heatwaves are one of the most dangerous climatic hazards affecting the health of humans and ecosystems around the world. Accurate forecasts of these dramatic events can be relevant for policy makers, climate services and the local population. In this perspective, the present study addresses the predictability of heatwaves in sub-seasonal to seasonal forecasts in the West Africa region over the recent period from 2001 up to 2020. Two models from the S2S Prediction project namely ECMWF and UKMO have been analyzed. Heatwaves have been detected using minimum/maximum values of 2-m temperature as indicators over a period of at least 3 consecutive  days. The validation of the model outputs is processed using ERA5 as reference. The global skill of the models in reproducing 2-m temperature is done by calculating the Continuous Rank Probability Score (CRPS). ECMWF model shows more skill in the Guinean region for minimum and maximum values of 2-meter temperatures.  The predictability of heatwaves in the models is estimated by the computation of some probabilistic metrics such as : hit-rate and false alarm ratio (FAR).  Models show predictive skill of heatwave days greater than the climatology up to 3 weeks lead time in the 3 regions. The FAR values are high and increasing with the lead time. This suggests that the models used to predict heat wave days which are not observed in the reanalysis (ERA5) more than real events. ECMWF shows more predictive skill at weekly time scale with high hit_rate values up to 3 weeks lead time. The accurate representation of the heatwaves intensity in the models remains very challenging at any lead time.
Critical taper analysis of the North Alpine Thrust Front, SE Germany – Influence of fluid overpressure on fault strength in a subaerial orogenic wedge
Authors: Duschl Florian , Schätz Antonia , Drews Michael
Published: February 2023

Weak detachments below active thrust fronts of subaerial orogenic wedges are mostly controlled by wedge taper geometry. A common method to investigate wedge properties is critical taper analysis. According to critical taper theory fault strength in a mechanically homogeneous wedge can be constrained from surface slope angle α and the angle of inclination of the basal detachment β. However, the influence of fluid overpressure on fault strength is often underestimated. Here, we present a simplified 3D wedge taper model of the North Alpine Thrust Front (SE Germany) between Lake Constance and the Inn Valley which is used for critical taper analysis. Different scenarios with varying input parameters are considered with special emphasis on fluid overpressure ratios.Critical taper analysis shows that frictional sliding resistance within the wedge varies both, laterally and longitudinally. Small fault strength values are predominant in the inner wedge, whereas the outer wedge is characterized by a higher fault strength due to a steepening detachment. Frictional sliding resistance in general decreases towards the hinterland likely resulting from lower surface slope values. For the western part of the North Alpine Thrust Front, our model shows low fault strength which is probably controlled by pore fluid overpressure and a flat detachment angle. Comparatively high fault strength in the eastern part however might be controlled by a steeper basal detachment, which is problay caused by underplating and a more complex structural framework. Finally, we use acquired data to discuss the influence of laterally varying sliding friction within the basal detachment on observed pore fluid overpressure in adjacent tectonic units, i.e. the Subalpine Molasse and the Foreland Molasse in Bavaria.
Observationally Constrained Cloud Phase Unmasks Orbitally Driven Climate Feedbacks
Authors: Hahn Lily , Sagoo Navjit , Storelvmo Trude , Tan Ivy , Danco James , Raney Bryan , Broccoli Anthony
Published: February 2023

The mechanisms that amplify orbitally-driven changes in insolation and drive the glacial cycles of the past 2.6 million years, the Pleistocene, are poorly understood. Previous studies indicate that cloud-phase feedbacks oppose ice sheet initiation when orbital configuration supports ice sheet growth. Cloud phase was observationally constrained in a recent study and provides evidence for a weaker negative cloud feedback in response to carbon dioxide doubling. We observationally constrain cloud phase in the Community Earth System Model and explore how changes in orbital configuration impact the climate response. Constraining cloud phase weakens the negative high latitude cloud phase feedback and unmasks positive water vapor and cloud feedbacks (amount and optical depth) that extend cooling to lower latitudes. Snowfall accumulation and ablation metrics also support ice sheet expansion as seen in proxy records. This indicates that well-known cloud and water vapor feedbacks are the mechanisms amplifying orbital climate forcing.
A stochastic shallow water hydro-sediment-morphodynamic model for uncertainty quantification in landslide modelling
Authors: Ji Li
Published: February 2023

Shallow water hydro-sediment-morphodynamic (SHSM) model has been widely used for landslide modelling. However, modelling hydro-sediment-morphodynamic (SHSM) processes is subject to multiple sources of uncertainty arising from input data and incomplete understanding of the underlying physics. A stochastic SHSM model with multiple uncertainties has yet to be developed as most SHSM models still concern deterministic problems and only one has been recently extended to a stochastic setting, but is restricted to a single source of uncertainty. Here we first present a new probabilistic SHSM model incorporating multiple uncertainties within the stochastic Galerkin framework using a multidimensional tensor product of Haar wavelet expansion to capture local, nonlinear variations in joint probability distributions and an operator-splitting-based method to ensure the modelling system remain hyperbolic. Then, we verify the proposed model via benchmark probabilistic numerical tests with joint uncertainties introduced in initial and boundary conditions, matching established experiments of flow-sediment-bed evolutions driven by a sudden dam break and by a landslide dam failure and large-scale rapid flow-sediment-bed evolution in response to landslides. The present work facilitates a promising modelling framework for quantifying multiple uncertainties in practical shallow water hydro-sediment-morphodynamic modelling applications.
Dry and wet climatic change and its driving factors in China
Authors: Tang Jie , Wang Wenting , Xie Yun
Published: February 2023

Evaluating the characteristics of long-term dry and wet climate changes under the background of global climate change is important for regional water resources security, ecosystem security and socio-economic development. Based on the daily meteorological data of 1680 meteorological stations in China from 1971 to 2019, the reference evapotranspiration (ET0) was estimated with the FAO-56 Penman–Monteith equation. Based on which, the temporal and spatial variations of humidity index (HI), precipitation (P), reference evapotranspiration (ET0) and the driving factors of which were further analyzed. Results showed that HI significantly increased in the northwest China of arid area, the northeast China of subhumid area and the Huang-Huai region of humid area, while it significantly decreased in the southwest and southeast China of humid areas. The change of HI can be mainly attributed to the change of ET0 while no significant trends has been detected for P for most regions of China. During the past 50 years, the increasing rate of ET0 was 3.76 mm/10a. But the temporal variation of ET0 are different from regions, and the increasing and decreasing area were mainly dominated by climate different factors. For region of Huang-huai and northern Northeast China, ET0 showed significant downward trend. Among factors that relating to ET0, wind speed contributes most to the significant decrease of ET0. For all rest regions of China, ET0 showed significant upward trends, and relative humidity contribute most to the increase. Key words: Dry and wet climatic change, humidity index, reference evapotranspiration, contribution, climatic factors.
An Atlantic interhemispheric teleconnection established by South American summer monsoon
Authors: Tseng Wan-Ling , Wang Yi-Chi , Lee Yu-chi , Hsu Huang-Hsiung , Keenlyside Noel
Published: February 2023

This paper reports the structure of an interhemispheric atmosphere–ocean coupling pattern, which occurs over the Atlantic Ocean from January to February, and refers to it as the Atlantic symmetric pattern (ASP). The ASP occurs in the middle–upper troposphere, with two trains of cyclonic–anticyclonic–cyclonic anomalous circulations aligned meridionally over the Atlantic Ocean. The sea surface temperature (SST) signature of the ASP, which is composed of a distinct SST dipole, is the leading mode of the interannual SST of the Southwest Atlantic Ocean. Experiments with the linear baroclinic model shows that the interhemispheric wave trains of the ASP can be excited as a Gill-type response to convection in the South American monsoon system and the South Atlantic convergence zone. Further studies are warranted to elucidate other aspects of the ASP, including teleconnection in the Northern Hemisphere and interactions with other climatic modes.
Knowledge Representation of Levee Systems - an Environmental Justice Perspective
Authors: Davarpanah Armita , Nguy Robertson Anthony.l , Lipscomb Monica , McCord Jacob.w. , Morris Amy
Published: February 2023

Levee systems are designed to reduce the risk of water-related natural hazards (e.g., flooding) in areas behind levees. Most levees in the U.S. are designed to protect people and facilities against the impacts of the 100-year floods. However, the current climate change is increasing the probability of the occurrence of 500-year flood events that in turn increases the likelihood of economic loss, environmental damage, and fatality that disproportionately impacts communities of color and low-income groups facing socio-economic inequities in leveed areas. The increased frequency and intensity of flooding is putting extra pressure on emergency responders that often require diverse, multi-dimensional data originating from different sources to make sound decisions. Currently, the integration of these heterogeneous data acquired by diverse sensors and emergency agencies about environmental, hydrological, and demographic indicators requires costly and complex programming and analysis that hinder rapid disaster management efforts. Our domain ‘Levee System Ontology (LSO)’ resolves the data integration and software interoperability issues by semantically modeling the static aspects, dynamic processes, and information content of the levee systems by extending the well-structured, top-level Basic Formal Ontology (BFO) and mid-level Common Core Ontologies (CCO). LSO’s class and property names follow the terminology of the National Levee Database (NLD), allowing data scientists using NLD data to constrain their classifications based on the knowledge represented in LSO. In addition to modeling the information related to the characteristics and status of the structural components of the levee system, LSO represents the residual risk in leveed areas, economic and environmental losses, and damage to facilities in case of breaching and/or overtopping of levees. LSO enables reasoning to infer components and places along levees and floodwalls where the system requires inspection, maintenance, and repair based on the status of system components. The ontology also represents the impact of flood management activities on different groups of people from an environmental justice perspective, based on the principles of DEI (diversity, equity, inclusion) as defined by the U.N. Sustainable Development Goals.
An integrated meteorological forecasting system for emergency response
Authors: Haefele Alexander , Hervo Maxime , Bättig Philipp , Leuenberger Daniel , Merker Claire , Regenass Daniel , Kaufmann Pirmin , Arpagaus Marco
Published: February 2023

EMER-Met is the new meteorological forecasting system for the protection of the population in Switzerland. It provides the meteorological basis for coping with all types of emergencies, especially in case of nuclear and chemical accidents. EMER-Met consists of a dedicated upper air measurement network and a high-resolution numerical weather prediction model. The measurement network is composed of state-of-the-art remote sensing instruments to measure accurate wind and temperature profiles in the boundary layer. At three sites, a radar wind profiler PCL1300, a Doppler lidar Windcube-200s and a microwave radiometer Hatpro-G5 are installed. The data from the measurement network are assimilated into the operational 1-km ensemble numerical weather prediction (NWP) system. In the case of the microwave radiometers, we assimilate the brightness temperatures using an adapted version of the RTTOV observation operator. To ensure best impact on the NWP results, the data quality of the measurements is of high importance and is monitored closely on a daily and monthly basis against radiosondes and the NWP model itself. EMER-Met is operational since 2022 and to our best knowledge, it is the first time that the brightness temperatures measured by surface-based microwave radiometers are assimilated operationally. This presentation will focus on the upper air network performance and its impact on NWP. 
Criteria for assessing the impact of nature-based solutions on groundwater systems
Authors: Selles Adrien , Herivaux Cécile , Le Coent Philippe , Marechal Jean-Christophe
Published: February 2023

Nature-based solutions (NBS) involve using natural systems such as wetlands, forests, and rivers restoration, to address challenges related to water, such as flooding, water scarcity, and water quality. Groundwater circulations and processes play a critical role in these natural systems. The solutions applied at the surface will have qualitative and quantitative impacts on groundwater, in this case, we propose the term NBS-GW (nature based solutions on groundwater). Therefore, the impact of the NBS on the groundwater systems should be assessed.The evaluation of NBS implemented with the objective of sustainable management of groundwater poses particular challenges related to the specificities of aquifers, invisible due to their underground location, whose functioning is complex and highly dependent on the geological context. Many factors influence the hydrogeological effects of a NBS-GW, including the climate, the topography of the watershed, the geology, but also the characteristics of the ecosystems concerned.The recharge of the aquifers allows to store water during times of plenty, and then it can be released gradually during times of drought providing sustainable base flow in the rivers, helping to mitigate the effects of water scarcity. Moreover, groundwater systems can act as a buffer against flooding by absorbing excess water during heavy rainfall events. NBS can have negative impact if not designed and implemented based on hydrogeological considerations. The benefits of NBS-GW can be maximized by combining different solutions and tailoring them to the specific conditions of a given area.This work aims to define the criteria to assess the effectiveness of different NBS in terms of their ability to recharge aquifers and improve water quality. NBS-GW can be distinguished according to the type of environment/ecosystem on which the solution acts, by preserving it, by improving its functioning, or by creating a new ecosystem. At the scale of a hydrogeological watershed, we will then distinguish between the solutions implemented (1) in agro-forestry environments, (2) in urban and peri-urban environments, or (3) aimed at aquatic environments.A review of the scientific literature was carried out in order to characterize the hydrogeological effects of NBS-GW by major type of environment (agro-forestry, urban, aquatic), and to identify the main factors of variation of these effects.These indicators of hydrogeological effects and efficiency could contribute to the list of NBS impact indicators recommended by the European Commission, which currently do not take groundwater into account.
An Intelligent Irrigation Decision Support System for Optimizing Cotton Water Use
Authors: Umutoni Lisa
Published: February 2023

Irrigation plays a crucial role in alleviating the negative effects of drought on crop production. However, increasing competition for water by other sectors, such as industry and domestic use, increases the pressure on available water supplies. Under these circumstances, agricultural producers must be able to manage their available supplies efficiently to optimize irrigation water use. The objective of this research is to develop a decision support system (DSS) for optimizing irrigation scheduling for cotton production using Deep Reinforcement learning (DRL). Our approach uses multiple DRL algorithms that enable an intelligent agent to learn cotton irrigation needs in an interactive environment by trial and error using feedback from its past actions and experiences. Aquacrop is used as an environment (cotton field) simulator and is coupled with a DRL model to simulate crop yield for different actions taken by the agent. Our proposed software estimates the daily irrigation needs of a 7-acre crop field irrigated by a center pivot system located at Clemson University's Edisto Research and Education Center (REC), near Blackville, South Carolina. This new system enables a closed-loop control scheme to adapt the DSS to local perturbations such as soil moisture and rainfall variabilities.
Resilient water governance under climate change within the WEFE Nexus (RETOUCH Nexus project)
Authors: Vrachioli Maria
Published: February 2023

With increased water scarcity due to anthropocentric and natural causes, the trade-offs and synergies intrinsic to efficiently allocating water resources to various competing uses have become more polarized. Realizing the importance of an integrated approach in water governance, the Water-Energy-Food-Ecosystems (WEFE) Nexus can be used as a multi-level and cross-sectoral approach that advocates the EU water economy and, in addition, relies on ecological and social considerations. The goal of this work is to propose, design and foster the adoption of integrated, innovative and inclusive Nexus-smart water governance schemes and institutional settings to promote a secure water future in the EU, resilient to climate change. This work follows an evidence-based approach to propose, assess and optimize a set of WEFE Nexus smart methods in six different case studies reflecting various cross-sectoral, multi-level and multi-stakeholder water governance contexts. To achieve this goal and monitor water governance in the EU we provide a set of Nexus-smart socio-economic and environmental indicators that reflect the cross-sectoral and multi-level nature of water use.  We also propose and develop economic instruments and business models that support robust water management under cross-sectoral competition. 
Rapid Grounding Line Retreat of Ryder Glacier, Northern Greenland, from 1992 to 202
Authors: Zhu Yikai , Zhou Chunxia , Zhu Dongyu
Published: February 2023

Ice losses from the Greenland Ice Sheet (GrIS) have expanded rapidly in recent decades. The Ryder Glacier (RG) is one of the major marine-terminating outlet glaciers located on the northwestern GrIS. Paying attention to its dynamic changes is of great significance to the study of the mass balance in the whole GrIS. We utilize the Double Differential Synthetic Aperture Radar Interferometry (DDInSAR) to detect the change of grounding line (GL) position in RG from 1992 to 2021. It is found that the GL has retreated significantly (1-8 km) during this period and its rate on the eastern and western flanks is nearly eight times different. To explore the reasons for the retreat, we combine the ice-shelf thickness variation, surface and bed topography, and potential subglacial drainage-pathway to discover that the basal melt governs the severe migration in RG. The uneven melting dominates the asymmetric retreat on the eastern and western flanks, which is caused by the disparity of ocean heat near the GL at different depths and the bed topography slope. The higher the ocean heat and the greater the slope are, the more intense the basal melt is, leading to further GL retreat and threatening the stability of the ice shelf. The experimental results also demonstrate that RG may continue to retreat, with a more drastic change in the west, in the coming decades.
Modelling compound flooding events for multiple hazards mapping: an example from Sweden.
Authors: Ashraf Faisal Bin , Passos Marlon Vieira , Barquet Karina
Published: February 2023

Globally climate change has increased exposure to multiple hazards. In Sweden, 10-year events of precipitation and streamflow have started to cluster around the summer months for most of the country. However, Sweden's south and west coasts are especially vulnerable to river flooding events caused by extreme sea surges during the winter. This national-level analysis needs to be combined with detailed local assessments to quantify the hazard properly, its potential impacts and cascading effects. In response to this need, we explore the impacts of multiple hydrometeorological (i.e., weather and water) events that happen simultaneously or close together in Halmstad. Furthermore, we investigate the effects of climate change on the intensity and frequency of these hazards by focusing on extreme – low likelihood but high impact – events. Due to its geographical location, Halmstad is particularly vulnerable to flooding risks. Wind and waves combine to make the city vulnerable to flooding and storm surges. That confluence triggers extreme local sea level rise, resulting in high sea levels in Halmstad compared to nearby coastal towns. These compound flooding events in Halmstad are expected to increase in future climate scenarios. We will simulate multiple scenarios of compound flooding events with a two-dimensional hydrodynamic model. The model's values used as boundary conditions will be based on computed joint return intervals for fluvial flooding and extreme sea surge. This study can not only be used to support local adaptation strategies but will also contribute to the body of knowledge on the issue of compound flooding events in a changing climate. Local-scale assessments like this one are necessary for a nuanced understanding of the possible impacts of multiple hazards on society. At the same time, societies' dependency on critical infrastructure and vital societal services is increasing due to growing system complexity and interconnectedness. Together, these shifts will likely increase societal vulnerability and impact adaptive capacity.
Development of 2.05 um Fiber Lasers for CO2 DIAL lidar Measuring Martian CO2 and Pressure
Authors: Liu Zhaoyan , Lin Bing , Campbell Joel , Yu Jirong , Jiang Shibin
Published: February 2023

A new concept of Martian differential absorption lidar (DIAL) operating in the 2050 nm CO2 absorption band for atmospheric CO2 and pressure observations has been proposed recently.  Based on the concept, we are awarded to develop 2.05 μm fiber lasers by the NASA Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Program. The laser is designed to be an all-fiber master oscillator and power amplifier (MOPA) system with laser output of ~3 mJ at a repetition frequency of 2 kHz.  The primary master oscillator (PMO) is locked to the center of the selected CO2 absorption line (2050.428 nm). The frequency of a second MO (SMO) is locked to that of PMO. This SMO frequency is adjustable and switched between the online (2050.44156 nm) and offline (2050.50812 nm) wavelengths for demonstration. The online wavelength is optimally selected so that the CO2 absorption optical depth (AOD) is ~1.1 at 3 km and the measurement in the low Martian atmosphere has largest signal-to-noise ratio. The online wavelength can also be adjusted to a line slope location where AOD is larger to observe atmospheric pressure at higher altitudes. We will present more detail about this project and instrument development at the conference. 
A Soil Data Platform to Inform Soil Health Investment
Authors: Sala Simone , Miglio Ester , Burra Dharani Dhar , Hopkins Austin
Published: February 2023

Healthy soil is critical to the growth of nutritious food and to farmers’ livelihoods. However, one-third of global soil is already affected by moderate to severe degradation by diverse processes. The reduction of soil degradation is one of the most important policy objectives, but policymakers and local planners require guidance in choosing  the most effective interventions, both scientifically and economically, to reduce soil degradation.  

The complex interconnections between agriculture, the natural environment, and social well-being increase the need of researchers to access and use comprehensive soil data sets. Our ability to manage and support soil depends on the data we collect and the information and knowledge that we generate from them. Nevertheless, soil data accessibility and sharing are currently low and represent one of the major barriers to making better decisions in agriculture. A critical first step to capitalize on the opportunities offered by agriculture science and technologies is thus the standardization, organization, and the making of the multitude of specialty datasets generated by studies and projects publicly available to the global community. 

To address this challenge, Varda is creating an interactive soil digital platform that allows surfacing and comparing existing soil data across the globe in order to facilitate soil data sharing and interoperability. Moreover, the platform highlights soil data gaps across regions through a soil data gap index, and particularly soil health data gap through another ad hoc index developed by Varda and Aberdeen University. Such indexes will allow multilateral organizations, governments, and agribusiness stakeholders to fill some of these data gaps through ad-hoc soil sampling and data collection campaigns.
Magnitude, trends, and variability of the global ocean carbon sink from 1985-2018
Authors: DeVries Timothy , Yamamoto Kana , Wanninkhof Rik ,   RECCAP2 Global Ocean Team
Published: February 2023

The RECCAP2 global ocean project provides an assessment of the mean, trends, and variability of the global ocean carbon sink for the period 1985-2018. The analysis is based on a comprehensive assessment of models and observation-based products, including global ocean biogeochemical models (GOBMs), pCO2 observation-based air-sea CO2 flux products, ocean data assimilation models, and DIC-observation based products. We find that the mean ocean CO2 sink from 1985-2018 is -1.7±0.3 PgC yr-1 as diagnosed by pCO2-observation based air-sea CO2 flux products. The dominant component of the global air-sea CO2 flux is the oceanic uptake of anthropogenic CO2, which is estimated at between -2.0 to -2.6 PgC yr-1 using a range of GOBMs, assimilation models and DIC-based products. The second largest component of the global air-sea CO2 flux is the outgassing of terrestrially-derived CO2, which is estimated at 0.65±0.3 PgC yr-1 but is not yet fully resolved by RECCAP2 models. The trend in the global air-sea CO2 flux from 1985-2018 ranges from -0.26 PgC yr-1 decade-1 in the GOBMs to -0.39 PgC yr-1 decade-1 in the pCO2 products. Over the 2001-2018 period, when the pCO2-based estimates benefit from improved data coverage, they predict a strengthening trend in the ocean carbon sink of -0.63 PgC yr-1 decade-1. This is driven primarily by the trend in anthropogenic carbon uptake of -0.41 PgC yr-1 decade-1, and secondarily by a climate-forced trend of -0.28 PgC yr-1 decade-1. This climate-forced strengthening of the ocean carbon sink since 2001 is not diagnosed in the GOBMs, and the reasons for this trend remain unclear. We find that the interannual to decadal variability of the global carbon sink is mainly driven by climate variability, with the climate-driven variability exceeding the CO2-forced variability by 2-3 times. GOBMs suggest that the climate-driven variability is about 4-8% of the global mean carbon sink, while the climate-driven variability is about 9-14% of the global mean flux in the observation-based pCO2 products. In all, the RECCAP2 analysis provides a state-of-the-art summary of our current knowledge of the ocean carbon sink, and the mechanisms driving its magnitude, trends, and variability over time.
Scattering of Giant Planets Around M-dwarf: The Implication for the Origin of the Hierarchical and Eccentric Two-planet System like GJ 1148
Authors: Yuan Longhui , Lee Man Hoi
Published: February 2023

GJ 1148 is an M-dwarf star, which has two well-separated Saturn mass planets with an orbital period ratio of around 13 and eccentricities of around 0.375 at the current epoch. A plausible scenario for producing the orbital architecture of the GJ 1148 system is planet-planet scattering. To test this scenario, we perform scattering experiments, assuming the third planet of 0.1 MJ (Jupiter’s mass) in the initial GJ 1148 system with initial orbital separations set to 3.5, 4, and 4.5 mutual Hill radii Rm,H respectively and initial semi-major axis of the innermost planet ai,1 in the range of 0.10-0.50 AU. The majority of scattering results in planet-planet collisions, followed by planet ejections, and planet removals as its distance to the star are smaller than a critical value of 0.02 AU. Among them, only the post-ejection two-planet systems have similar properties to the GJ 1148 system, and when ai,1 is around 0.21 AU, the semi-major axis of the inner planet GJ 1148 b can be reproduced. We further perform simulations with ai,1 in a narrower range between 0.16 and 0.30 AU, and found one system with similar orbital properties to the GJ 1148 system. Therefore, the simulation results suggest that the GJ 1148 system may have lost a giant planet. The two-sample Kolmogorov–Smirnov (KS) test on simulations with and without GR apsidal precession shows that it does not affect the ejection outcomes. When setting the mass of the third planet to 0.227 MJ of GJ1148 c, the optimal ai,1 move to about 0.29 AU.
Characterizing the transition from diffuse to localized deformation using optical image correlation: the 2021 Mw7.4 Maduo, Tibet, earthquake
Authors: Antoine Solene L , Liu Zhen , Klinger Yann , Delorme Arthur , Liu-Zeng Jing
Published: February 2023

The 2021 Mw7.4 Maduo earthquake generated a ~160 km-long fault rupture within the Eastern Tibetan plateau, at about 100-150 km to the south-west of the Eastern Kunlun fault. Fault slip measured on the field represents only 20% of the displacements from satellite Interferometric Synthetic Aperture Radar (InSAR) measurements, highlighting the primarily diffuse nature of the surface deformation for this earthquake. Most surface deformation associated with this event corresponds to diffuse shear, occurring over widths of a few hundreds of meters to a few kilometers, and sometimes associated with shearing and tensional cracks mapped in the field. In this study, we use sub-pixel correlation of Pleiades (0.5 m) and SPOT-6/7 (1.6 m) optical images to characterize the near-fault displacement patterns associated with the 2021 Maduo event. We also use other optical data to assess the impact of sensor resolution on the measurements. Our results cover three kilometers on both sides of the rupture area with a resolution of 0.5 m. These results show that, despite the large rupture gaps observed in the field, the shear deformation zone at the surface is continuous along the entire length of the 2021 rupture. Even though, we observe variations in the surface deformation patterns, with regions that present more localized deformation whereas others are primarily characterized by diffuse shear. Using the high-resolution displacement maps, we characterize the transitions from the localized to the diffuse shear along the rupture strike, and investigate the relations with the bulk rock properties, and coseismic slip distribution. We also determine the limit at which deformation starts to localize on fractures that are large enough to be visible in the field.
Astronomic influences on seasonal to interannual variability in saltwater intrusion in a subtropical estuary
Authors: Valle-Levinson Arnoldo , Laurel-Castillo Jorge Armando
Published: February 2023

A 10-year time series of surface salinity values along an estuary-river transition documents their spatial structure and their temporal variability. Decomposition of detided time series into empirical modes indicates that the first mode, explaining almost 95% of the overall variance, has the typical sigmoid spatial structure found in estuaries. The temporal variability of mode 1, referred to as salinity index, displays annual and semiannual signals that are modulated from year to year. A fit of the salinity index to harmonics associated with luni-solar orbital motions and solar activity explain more than 70% of the index variance. This suggests that a) gravitational forcing from moon and sun, and b) the thermodynamic influence of solar activity, both impact salinity intrusions into rivers. The mechanistic linkage is unknown, but it is likely that it develops through atmospheric pressure, winds, air temperature, and water level. These variables are influenced by gravitational forcing and solar activity as observed elsewhere. The main finding is that the salinity variability at an estuary-river transition is influenced by gravitational forces and solar activity, i.e., saltwater intrusion could be determined by the modulation of astronomic influences. Similar variability may be found for mixing processes in coastal regions. 
Solid Carbon: Safe and Durable Carbon Storage in Ocean Basalt - From Feasibility to Demonstration to Global Potential
Authors: Tutolo Benjamin , Scherwath Martin , Moran Kate , Goldberg David , Awolayo Adedapo , Coogan Laurence , Crawford Curran , Dosso Stan , Ekpo Johnson Eneanwan , Lauer Rachel , Louis Emma , Nawaz Sara , Satterfield Terre , Slagle Angela , Todd Devin , Webb Romany
Published: February 2023

Oceanic crustal basalt rock has been identified to be the most abundant CO2 sequestration reservoir on earth with a total capacity of up to 250,000 Gt of CO2 and the added advantage of the CO2 mineralizing into carbonate rock in the safest and most durable way. Experiments and pilot projects have established geologic carbon storage in basalt on land (e.g. Carbfix in Iceland) but have not been carried out offshore and are therefore required to demonstrate and prove this form of carbon storage offshore. We are presenting the ongoing Solid Carbon project, which is currently in the feasibility stage of demonstrating this concept in the Cascadia Basin offshore Vancouver Island where Ocean Networks Canada operates a cabled ocean observatory, which will be utilized to monitor and verify this form of geologic carbon storage. The demonstration site is at about 2700 m water depth, where the ocean crust is overlain by 200-600 m of sediment acting as a cap for the porous and permeable crustal basalt aquifer (300-500 m thick), underlain by a thick conductive basement. From previous seafloor drilling campaigns, the subsurface and hydrogeology in this area are well known, feeding both into sequestration modelling and also planning the required monitoring. In addition to planning the offshore demonstration experiment, the Solid Carbon project further includes research on social, regulatory and social acceptance as well as adding offshore energy and direct carbon capture to transform the concept into a negative emission technology. We will present the past, present and potential future of this form of geologic carbon storage.
Exploring New Instrument deGradation Models and Algorithms (ENIGMA)
Authors: Béland Stéphane , Penton Steven
Published: February 2023

The Solar Radiation and Climate Experiment measured Total Solar Irradiance (TSI) and Solar Spectral Irradiance (SSI) from 2003 to 2020. The Solar Irradiance Monitor (SIM) instrument measured SSI from 200nm to 2400 nm on a daily basis. The current SORCE-SIMinstrument degradation correction uses a measurement equation derived fromaccessible telemetry, the known instrument refraction geometry, inter-detector comparisons,and inter-spectrometer comparisons. While the current degradation model captures much of thelong-term trending, some of the parameters were adjusted without well-defined physicalinterpretations.The degradation model used for SORCE-SIM is not unique. We're reporting on work to Explore NewInstrument degradation Models and Algorithms (ENIGMA) to address issues with the currentmodel and with the derived corrected irradiances. The development of enhanced SORCE-SIMmeasurement equations permits the evaluation, and potential inclusion, of degradationmechanisms not captured in the present model.We present an initial updated degradation model which improves our ability to construct a composite irradiance time series in combination with TSIS-SIM, whose measurements overlap with SORCE for 2 years and has well-defined uncertainties. Combining the two datasets, allowedthe construction of a consistent composite irradiance time series from 2003-2023. 
The environment surrounding the subduction zone plate interface
Authors: Mann Michael Everett , Abers Geoffrey , Fulton Patrick
Published: February 2023

The interface between a subducting and overriding plate usually exhibits low seismic velocities within a thin (<6 km thick) layer. The hydrologic and petrologic conditions surrounding this layer control the behavior of the plate interface fault, which shows a wide range of rupture behavior from the megathrust through the down-dip transition to tremor and slow-slip. Many analyses of the properties of this plate interface low-velocity layer (LVL) use receiver functions (RFs), which sample sharp seismic velocity gradients and depend primarily on the time separation between RF phases from the top and bottom of the layer, to provide diagnostic estimates of thickness and Vp/Vs. Previous hypotheses for plate interface rupture behavior have invoked high pore-fluid pressure to explain inferences of apparently high Vp/Vs (exceeding 2.2) along the seismogenic zone and the adjacent down-dip slow-slip region determined from RF analyses. However, new higher-resolution analyses of scattered teleseismic P-wave coda that sample this region in two different subduction zones reveal Vp/Vs within the range of normal lithologies (1.6-2.0) and remove the observational requirement for a thick region of high pore-fluid pressure. These results agree with recent laboratory analyses of the properties of exhumed megathrust rocks. Instead, the mechanical properties of a thick damage zone surrounding the interface or entrained sediments explain both the scattered-wave observations and observed fault rupture behavior in the seismogenic zone and deeper. Pore pressure could play a role, but it may operate more locally or intermittently than conventionally thought. Additionally, from this analysis we find that the frequency content of the scattered phases generated at the delimiting boundaries of the LVL are limited and do not provide enough resolution to include direct (up-going P-to-S converted waves) conversions in LVL RF analyses without biasing the results to high values of Vp/Vs and thickness.
Geodiversity and the fate of alpine plant communities in a changing climate
Authors: Malanson George
Published: February 2023

Geodiversity has been identified as the basis for the persistence of alpine vegetation during climate change. Geodiversity relevant to the current plant community composition in three alpine regions of the Rocky Mountains, USA was evaluated. Vascular plant cover and continuous and ordinal indicators of geodiversity were recorded in the field, and indicators of topographic wetness and insolation were calculated. In each region, the contribution of these variables to the variation in nonmetric multidimensional scaling of vegetation was determined using random forest models. The models differed among the regions: water variables were more important in the northern region, energy was more important in the southern region, and the central region had a more equal partitioning. The determinants of plant community variation differ predictably along regional climate gradients, and therefore geodiversity features as refugia, or their opposite – ‘hazardia,’ will vary among future climates, and the impacts on plant communities will differ.