bluuebunny/crossref_metadata_2025 huggingface dataset:
Sea water chemistry in the late Paleoproterozoic: Insight from the Huangqikou formation, western part of the North China Craton
Authors: Ma Qing , Zhou Yaoqi , Zerkle Aubrey
Published: February 2023

The ~1800–800 Ma period is known as the 'Boring Billion (BB)' because of the relative stasis of the carbon isotope record during this time. However, geochemical data from the Paleo-Mesoproterozoic strata deposited in different areas indicate heterogeneity and complexity of the oxygen contents in the oceans, which hampers paleoenvironmental reconstructions from this period. In addition, very little research has been carried out on the Palaeoproterozoic strata of the North China Craton (NCC). In this study, we report analyses of U-Pb isotopes, elemental abundances, Fe speciation, and molecular markers from the Huangqikou formation in the northwestern part of the Ordos Basin (OB), NCC. The Huangqikou formation was deposited in the rift valley at about 1736 Ma. Our new data, combined with previous analyses, suggest that the warm and humid depositional environment of the Huangqikou formation in the Helanshan area evolved from a marine foreshore setting to a marine backshore setting, with increasing degree of seawater hypoxia. But a relatively oxygenated environment corresponded to the lower part. On the other hand, the Huangqikou formation in the Zhuozishan area evolved from a terrestrial deltaic environment to a marine foreshore environment, with cumulatively reducing conditions. This study points out that the late Paleoproterozoic strata deposited in the western part of the NCC might mainly formed in reduced seawater. But some degree of oxidation had occurred in the surface water during this period, which proves the oxygenation of the surface environment during the early period of Earth evolution.
Combining minero-petrological and geomorphological analyses at active volcano-tectonic and hydrologically hazardous areas: a case study on Montagnone-Monte Cito at Ischia (southern Italy).
Authors: Mormone Angela , Caputo Teresa , Marino Ermanno , Balassone Giuseppina , Piochi Monica
Published: February 2023

The combined use of minero-petrological analyses and drone photogrammetry may represent a powerful way to better understand the dynamics of hazardous geological environments. This can help to map, investigate and monitor volcanic structures that are modifying by actual processes, particularly through the creation of a time series of spatial data able to evidence the geomorphological evolution and mechanical features variation of landscapes.In this study we investigate the relationships between acid sulfate weathering, geostructural framework and geomorphological changes that can be observed at active volcanic hydrothermal systems. The investigated area is Montagnone-Monte Cito, site of high temperature geothermal activity, flank instability and disastrous seismicity in historical and recent times. The target area, in fact, is the one closest to the city of Casamicciola, remembered as the epicenter of the destructive volcanic-tectonic event (approx. magnitude 4.0) which took place on August 21, 2017 and was unfortunately destroyed by a powerful landslide on November 26, 2022.Photogrammetry of proximity survey, geological field campaign, mineralogical and geochemical analysis with Optical Microscopy (OM), X Ray Diffraction (XRD), Electron Microscopy and Energy Dispersive microanalysis (SEM-EDS), and handheld X-Ray Fluorescence (XRF) to characterize altered outcropping deposits, were repeatedly carried out in the area. We present multitemporal analysis based on the comparison of 3D data obtained by UAV photogrammetry techniques. We comparison two dataset acquired in 2022 for each of which we obtained a 3d point cloud, that has provided the setting of the area at the different times and its evolution through their comparison evaluating volumetric changes.Modifying sites have been examined in the field and characterized for mineralogical and geochemical features. Our methodological approach appears promising to evaluate evolution and rock fall susceptibility of solfataric terrains subjected to hydrothermal dynamics.
Modelling the transport of microplastic pollution across the Antarctic Circumpolar Current
Authors: Wilson Daniel R , Sheen Katy L , Clark James R , Thorpe Sally E , Young Emma F
Published: February 2023

Microplastic pollution is a ubiquitous marine environmental contaminant that is found in all the world’s oceans. The Southern Ocean is not exempt from microplastic pollution, with numerous studies reporting microplastics to be present in the region, including south of the Antarctic Circumpolar Current (ACC). However, the challenges involved in collecting data on microplastic pollution in the Southern Ocean mean there are large areas of the Southern Ocean where microplastic pollution levels are largely unknown. In addition, the processes and resulting transport pathways that move microplastic pollution across the ACC into the highly sensitive Antarctic marine ecosystem are not yet well understood.To tackle these knowledge gaps, we use a modelling approach to simulate the transport pathways of microplastic in the Southern Ocean, with a specific focus on cross-ACC transport. Specifically, we use the Lagrangian particle tracking framework OceanParcels, forced with ocean velocity fields from a Southern Ocean configuration of NEMO-LIM3 with 1/12॰ horizontal resolution. This model set up, which includes the effect of Stokes drift and sub-grid scale diffusion alongside underlying ocean currents, has allowed us to identify key regions where surface microplastic pollution may cross the ACC and potential hotspots of microplastic accumulation along the Antarctic coastline. We describe seasonal and inter-annual variability in microplastic transport through analysis of 22 years of model output, and suggest potential drivers of this variability. The results of our study will inform future field research into microplastic pollution in the Southern Ocean.
Restructuring the Indian agricultural system toward sustainability and lower environmental costs
Authors: Bhatia Udit , Goyal Shekhar , Kumar Rohini
Published: February 2023

The evolving international conflicts have a rippling effect on global food security, forcing nations to impose new trade laws to increase their domestic supply at reduced prices and promote the need to develop local and regional food systems to reduce transboundary dependence. While aiming to become a major global food supplier, India faces significant domestic food security risks. India has achieved food security through injudicious fertilizer application on the domestic front. Past agricultural policies, while primarily focusing on maximizing production, paid less attention to their environmental consequences. India feeds 17.1% of the world's population, with 10.7% of the world's arable land: this will further increase with increasing national and international food trade. Sustainably feeding the growing population has garnered considerable attention; however, its national implementation still needs to be improved. The current intensive agricultural practices operate at low water, nutrient, and nutritional efficiencies, demanding high input for high output. As a result, Nitrogen, Phosphorus losses are high, and groundwater resources are depleting in some areas. The vexing question is how to produce sufficient food in the existing regions with minimum inputs and reduced environmental impact. For this, India must reconfigure its current cereal crop production and interstate crop distribution system by reducing nutrient pollution losses, greenhouse gas emissions, and water consumption while sufficing its increasing nutritional demand. Using a state-of-the-art framework from agricultural sciences, network, and resource optimization, our study provided ways toward national assessment of Indian staple crop system redesign for future sustainable intensification.  Further, by incorporating interstate trade within this restructured system, we try to understand how India's cereal crop redistribution will impact domestic food security. Thus to limit the environmental burden of the growing consumer demand, we optimized crop distribution and domestic trade patterns within the parameters of minimizing nitrogen and phosphorus losses. This realistic multi-dimensional framework will help India and other nations identify sustainable food security solutions. 
Diel and seasonal methane dynamics in the shallow and turbulent Wadden Sea
Authors: de Groot Tim , Mol Anne , Mesdag Katherine , Witte Harry , Ndhlovu Rachel , Ramond Pierre , Engelmann Julia , Röckmann Thomas , Niemann Helge
Published: February 2023

The UNESCO world heritage Wadden Sea is a highly productive coastal system, rich in biodiversity and influenced by physical and biological forcing. Such coastal seas are known to dominate ocean’s methane emissions, but knowledge on variations and controls of methane and the efficiency of the microbial methane filter in these vastly dynamic systems are scarce. We conducted high frequency sampling over a 2-days’ period during four seasons to determine diel and seasonal effects on methane dynamics in the Dutch Wadden Sea. We found that waters were charged with methane throughout the year with maximum concentrations of up to 155 nM in summertime. Methane concentrations were generally lower at high tide and in the colder seasons, whereas MOB activity increased by ~2-fold during low tide compared to high tide. On average, only a minor fraction of the WZ methane budget (~2%) is retained by MOBs in the WZ itself, while ~1/3 escapes to the atmosphere and ~2/3 are flushed out into the open North Sea where it may be consumed by microbes or is liberated to the atmosphere.
Use and recovery of mining waste and tailings for sustainable management of works related to extractive activities
Authors: Dino Giovanna , Mancini Susanna , Casale Marco , Lasagna Manuela
Published: February 2023

Extractive waste (EW), including tailings, are produced in large quantities during mining activities.In recent years, the linear economic model (based on “take-use-and-throw” approach) has been replaced by a circular approach, in which even waste and extractive residues acquire importance through sustainable use and recovery.The use and recovery of EW shows also positive technological (in term of technological innovations), economic and social (in terms of new expertise and skills linked to sustainability), and environmental impacts (to be evaluated and faced to reduce the ecological footprint).The use and recovery of EW takes place through the application and development of innovative protocols linked to waste exploitation (sustainable and environmentally friendly), i.e. BAT, which aim at the technological and process improvement of the activities and at the production of renewed, highly performing green materials. Mining waste and tailings, if suitably characterized, can be used to improve and make sustainable the works connected to the management of mining activities.The qualitative-quantitative characterization of EW is essential not only for any subsequent reuse but also for assessing the extent of environmental impacts (AMD, dust, high concentrations of heavy metals, etc.) in the various matrices and risk to human health and the environment.The application areas of use vary according to the type of waste and mining tailings, the morphological characteristics of the deposits, and the geological, geomorphological and logistic context of the area.In this study, some examples of sustainable use of tailings and mining waste are presented (i.e. use of calcareous tailings to reduce acid drainage and the production of artificial substrates for environmental rehabilitation, waste for mining backfills, waste/landfill waste recovered for extraction RM/CRM, etc.). Further to this, positive impacts on the economic, environmental and technological/social level are also analysed. The latter actions, together with energy saving and the adoption of appropriate financial instruments, contribute to the transition of mining activities into "sustainable mining".
Flood Risk in Vietnamese Coastal Cities – Remote Sensing Based Urban Structure Types as a Planning Relevant Tool
Authors: Hochschild Volker , Braun Andreas , Schultz Michael , Warth Gebhard
Published: February 2023

Coastal and delta cities in Vietnam like Ho Chi Minh City, Da Nang, or Hué are exposed to multi-hydrometeorological hazards caused by heavy rainfall, typhoons, tsunamis, rising sea levels, land subsidence as well as river flooding, intensified by global climate warming. Being exposed to these regular events, different degrees of spatial vulnerabilities are resulting for the citizens in relation to their distance to water ways or height above sea level, but also their capabilities to recover from possible hazards.Since development of many Southeast Asian cities is extremely dynamic, city planners are lacking relevant planning information on population numbers and material flows (waste, drinking water demand, wastewater disposal, energy consumption, etc.), which are usually not provided by outdated masterplans. For that reason, so called Urban Structure Types (USTs) can be defined and derived from high-resolution remote sensing data. They are basic urban spatial units with homogeneous functional and morphological structure, delineated by shape, form, height, material, and density parameters. USTs are independent, quantifiable, and generic and thereby providing a surplus information to urban land cover classes. Their final classification is achieved by machine learning approaches applied to high and very high resolution imagery. A discrimination is made between globally applicable parameters like building height, size, or density and locally adjusted parameters like e. g. distance to water way or street width which are additionally required to cover the character of the individual cities.   Urban Structure Types are a crucial input for hydrological modelling as well as damage modelling approaches, but they are also correlated with socio-economic data collected by questionnaires and interviews in several sampled quarters of the cities. As a conclusion, the USTs might indicate different ways of living within the city and give hints to consumption patterns but also topics of environmental justice.
ABACUS – a repeated glider monitoring line across the western Mediterranean Sea
Authors: Cotroneo Yuri , Aulicino Giuseppe , Fusco Giannetta , Ruiz Simon , Pascual Ananda , Testor Pierre , Cauchy Pierre , Zarokanellos Nikolaos , Miralles Albert , Zerrouki Mohamed , Tintoré Joaquin , Budillon Giorgio
Published: February 2023

Algerian Basin Circulation Unmanned Survey – ABACUS - has been carried on since 2014 across the Algerian Basin to investigate high resolution variability of the first 1000 m of the ocean and to fill the gap in data collection in this area of the Western Mediterranean Sea.Five deep SLOCUM G2 glider missions were carried out in the AB between 2014 and 2022 by Università degli Studi di Napoli Parthenope, in collaboration with Balearic Islands Coastal Observing and Forecasting System (SOCIB) and the Mediterranean Institute for Advanced Studies (IMEDEA CSIC-UIB), with the participation of scientists from Algeria, France and Canada. A sixth mission (ABACUS 2023) is indeed in progress. ABACUS projects were supported since 2014 through the Trans National Access (TNA) calls of JERICO, JERICO-NEXT and JERICO S3 programmes and through the SOCIB glider facility open access programme.Recently, ABACUS line was also added to the Boundary Ocean Observing Network (BOON) of the OceanGliders programme that proposes the long term and sustained observation of oceanographic features using the unique capabilities of the gliders.To date, a total of 22 deep glider ABACUS transects were realized between the island of Mallorca and the Algerian coast. Each mission had an average duration of about 40 days and was mainly carried out during fall and/or early winter (2014–2018, 2021-2022) or spring (2018, 2022). All the glider surveys were conducted along neighboring SARAL/AltiKa (2014-2016) and Sentinel-3A (2018, 2021-2022) satellite groundtracks. The timing of the glider missions were accurately planned to optimize the synopticity between in situ and remote sensed observations.All the ABACUS gliders were equipped with a glider-customized CTD measuring temperature, conductivity/salinity and pressure/depth; a two-channel combo fluorometer sensor by WetLabs (for Chl-a concentration and turbidity measurement); and an oxygen optode by AADI to measure absolute oxygen concentration and saturation. During the last two missions, the glider was also equipped with a passive acoustic probe to study wind and rain events during the mission, as well as the presence of marine mammals in the monitored area.ABACUS data are freely available through a dedicated webpage and cooperation with new scientists is strongly encouraged. This presentation aims at making the scientific community aware of the importance and possibilities offered by ABACUS and similar glider monitoring lines, as well as at enlarging the ABACUS science team to fully exploit the collected ocean observations.
Assessing the impacts of land use/land cover (LULC) change and the effects of nature-based solutions in Andean basins.
Authors: Fonseca Kalina , Ramírez Miguel , Martínez William , Espitia Edgar , Breuer Lutz
Published: February 2023

The limited spatial scope of Andean basins conservation agreements by nature-based solutions (NbS) in the tropical alpine grassland region (páramos) has led to unequal protection of upstream ecosystems, endangering the water quality downstream of large Andean cities. Simultaneously, the páramos have been converted to other land uses in response to the political, economic, social, technological, ecological, and legal (PESTEL) factors. In this context, we aim to compare the negative impacts associated with land use/land cover (LULC) change and the positive effects of nature-based solutions in the upper Andean basins using remote sensing data, PESTEL analysis, and water quality assessment. The upper basin of the Pita and Cutuchi rivers, located above 3,000 m.a.s.l., which supply drinking and irrigation water to two major Andean cities in Ecuador, i.e., Quito (the capital of Ecuador) and Latacunga (an important city for floriculture and agriculture), were examined in comparison as case studies between 1999 and 2022. Our results reveal significant land-use changes from páramo to agriculture, Pinus plantations, urban growth, and mining areas in the upper basin of the Cutuchi river, driving water quality between low to moderate for drinking and irrigation purposes. According to the PESTEL framework, the main factors contributing to the lack of upper basin protection are (1) short-term policies in line with the political party, (2) state budget planning that does not meet restoration needs, (3) conflicts between the upper, middle, and lower river basin communities, (4) lack of public investment in technological tools, (5) agricultural practices in the páramo due to high soil carbon storage in comparison to other areas and (6) conflicting laws between administrative divisions. In contrast, main páramo areas have remained unaltered or passively restored in the upper basin of the Pita river by the combination of NbS and policies implemented by water funds, conserving good water quality. By using these catchments as ideal natural laboratories, we can demonstrate the positive experiences through NbS in river basin management. Together with our PESTEL analyses, it is possible to develop integral conservation projects that ensure human health and sustainable agricultural productivity in the context of Sustainable Development Goal (SDG) 6: Clean Water and Sanitation.
A Transformer-Based Analysis of Tweets in Germany to Investigate the Appearance and Evolution of the 2021 Eifel Flood in Social Media
Authors: Veigel Nadja , Kreibich Heidi , de Bruijn Jens A. , Aerts Jeroen C.J.H. , Cominola Andrea
Published: February 2023

In July 2021 several European countries were hit by severe floods. Estimates by SwissRe indicate that a flood event caused by the low-pressure area “Bernd” caused 227 deaths and economic losses of 41 billion USD in Central and Western Europe, with hotspots in Germany, Belgium, and the Netherlands. An increasing number of studies focus on understanding and modelling the causes and evolution of this event, developing reliable estimates of the losses it caused, and recommending improved disaster management strategies. However, risk communication and flood-related citizens’ behaviors, attitudes, and perceptions before, during, and after the flood are currently understudied.Here, we develop an analytical framework to extract information on these human-related elements based on social media data. We ultimately aim to understand how flood warnings, intensity and impact are reflected in social media topics. To this extent, we analyze differences between topics arising on social media for an event like the 2021 flood compared to less devastating floods that occurred in the past. This requires homogeneous automatic assessment of Twitter data over time. We analyse the content of 42,000 tweets containing selected keywords related to flooding posted in Germany since 2014. Keywords refer to both fluvial and flash floods. Bidirectional Encoder Representations from Transformers (BERT) in combination with unsupervised clustering techniques are implemented to classify the tweets in different topic groups (BERTopic). Further, we extract the temporal evolution of topic patterns for different flood types and phases of flooding. Our analysis contributes to understanding the patterns of key topics, reflecting behaviors before, during and after the flooding event - thus how these topics change over time. Using the new framework and understanding these dynamics supports (i) modelling risk communication, behavioral drivers, and social interactions in relation to different types of floods with different intensities, and (ii) identifying indirect flood impacts that are not reported in traditional flood documentation. Finally, our approach can be extended for analysis of other natural hazards as well as compound events.
Fireworks: A Major source of elemental aerosols during Diwali in Delhi-NCR
Authors: Faisal Mohd , Ali Umar , Singh Vikram , Kumar Mayank
Published: February 2023

Fireworks activities worldwide seem to play a significant role in air quality degradation, especially during different events that lead to worsening air quality in the form of ambient particulate matter (PM) pollution. The fireworks activity in Delhi is one of the primary cause for the considerable increase in the particulate concentration during Diwali in Delhi. The substantial increase due to extensive firework activity results in enhanced metal concentration in the atmosphere. Therefore a comprehensive understanding of fireworks induced into the atmosphere is crucial to develop an enhanced mitigation strategy. Thus this study focuses on the comparative analysis of fireworks used in Diwali for the years 2019, 2020 and 2021. The current analysis studies the impact of Diwali for three consecutive years on the concentration, composition, and sources of ambient PM2.5. The measurement of elements in PM2.5 was performed with half-hourly time resolution using the Xact 625 Ambient Metals Monitor. The 12-hour average concentration of metals during Diwali night for 2019, 2020 and 2021 are 181 ug/m3, 117 ug/m3, and 151 ug/m3, respectively. Concentration levels of species like K, Al, Sr, Ba, and S displayed distinct peaks during the firework event and were identified as tracers for the same. We conducted source apportionment by positive matrix factorization (PMF) of the elemental mass measurable by the Xact. The source apportionment study indicated that more than 85% of elemental mass had been apportioned to firecrackers during Diwali. The reported enhancement in the mass concentration of elemental metals like Al, Ba, Cl, Pb, and Mn poses a severe threat to the health of the exposed population as the average mass concentration of these species exceeded the standard EPA risk-based levels by orders of magnitude during the Diwali phase. Moreover, possible carcinogens like As also exceeded the risk-based concentration significantly.
Freeze-thaw effects on pore space and hydraulic properties of agricultural soils – a summary of studies and implications for the temperate-boreal zones in a changing climate
Authors: Klöffel Tobias , Larsbo Mats , Jarvis Nicholas , Barron Jennie
Published: February 2023

Freeze-thaw (FT) cycles have shown to affect the evolution of the pore space of agricultural soils, thereby affecting their hydraulic properties. In the temperate-boreal zones, FT patterns are projected to shift from relatively long and uniform freezing periods to more frequent fluctuations around 0°C as a result of climate change. To better anticipate potential consequences for water storage and flows in agricultural soils, a thorough evaluation of the importance of FT cycles in this context is required.Here we summarize the findings of studies investigating the effects of FT cycles on various pore-space characteristics (e.g. macroporosity, pore connectivity, percolating pore space) and hydraulic properties (e.g. infiltration capacity, hydraulic conductivity, water retention) of agricultural soils. This includes the results of a laboratory experiment where we simulated different FT scenarios representative for current and future winter conditions in the temperate-boreal zones.Our findings suggest that a shift in FT patterns with climate change indeed has the potential to alter, at least temporarily, water retention properties and (near-)saturated hydraulic conductivities of agricultural soils. We highlight that this is despite most changes in pore-space characteristics seem to occur in pores with a diameter smaller than 50 µm. The persisting increase in pore connectivity of specific soils with an increasing number of FT cycles appears to be decisive in this respect. However, to assess fully the magnitude of changes in soil water functions at the field scale may require modelling. We finally stress that the sensitivity of hydraulic properties to FT patterns questions the transferability of results of some previous studies to the natural environment, applying unrealistic temperatures and rates of freezing and thawing.
Challenges of long-term AMOC prediction due to riddled basins in coupled atmosphere-ocean models
Authors: Seshadri Ashwin K , Stainforth David
Published: February 2023

Low-order coupled models of the atmosphere and ocean can illuminate the role of weather-climate interactions in long-term climate prediction. An important example is models that bring together the interplay between the Atlantic meridional overturning circulation (AMOC) with mid-latitude quasi-geostrophic dynamics of the atmosphere, as in the coupled model introduced by Van Veen et al (2001). In such models, the AMOC can transition from its present thermally driven to a much weaker salinity-driven state, through a tipping point. We show using these coupled models that, for scenarios with intermediate forcing between a strong and weak circulation, the long-term evolution shows extreme sensitivity to initial conditions, due to the appearance of riddled basins of attraction. The literature on dynamical systems has extensively examined such dynamics when two distinct basins of attraction are riddled, that is any small part of one attractor’s basin also includes a piece of the other. Moreover, in the presence of feedback from the atmosphere to the ocean, initial atmospheric conditions are amplified to the extent that long-term prediction in these models is inhibited by the finite precision at which the atmospheric state is known. We propose to describe the various facets of this phenomenon and consider the lessons for understanding and predicting long-term climate (in our case, thermohaline circulation), given initial state uncertainty. Furthermore, the resulting challenges of long-term prediction are not necessarily ameliorated by the real-world asymmetries in the model. When the relevant symmetries that yield riddled basins are broken through perturbations to the vector fields, the asymptotic dynamics become perfectly predictable given the initial conditions; however, long-term uncertainties in the transient state (strong vs weak circulation) persist for centuries, owing to ocean timescales. 
Land use management effects on water yield and hydrological connectivity after rural abandonment in a mid-mountain basin: Leza Valley (Iberian System, Spain)
Authors: Llena Manel , Zabalza Javier , Cortijos-López Melani , Lasanta Teodoro , Nadal-Romero Estela
Published: February 2023

During the second half of the 20th century the mountain areas of the Mediterranean region undergone an intense process of rural abandonment. This process together with a transition to warmer and drier climatic conditions caused a decrease in runoff and sediment yield, which have several consequences from hydrological, geomorphological and ecological points of view. Land use management of these areas has become a target of environmental authorities and stakeholders to ensure the sustainability of ecosystem services. An active management has been applied in some areas through the reduction of vegetation density or by human afforestation, while other areas have not been managed, undergoing a natural process of revegetation. In this context, assessing the contribution of different land use management on runoff is fundamental for addressing water management at the catchment and regional scales, especially in a context of climate change. The main objective of this work is to analyse the relative effects of land use management techniques to hydrological connectivity and water yield in a Mediterranean mid-mountain basin. To pursue this objective, we applied hydrological connectivity (IC index) and ecohydrological (RHESSys) models to different sub-catchments of the Leza Valley (Iberian System, Spain), representative of three different scenarios: (i) natural revegetation, (ii) human afforestation, and (iii) shrub clearing. Results show how hydrological connectivity tends to decrease when vegetation cover increases (i.e., natural revegetation and human afforestation) while tends to increase when shrub clearing takes place. Runoff coefficient followed a similar pattern, decreasing in basins where vegetation increases and decreasing where there is vegetation clearing. Important differences were observed in terms of the distribution of connectivity changes, their location in relation to the outlet and the effects on surface runoff.This research project was supported by the MANMOUNT (PID2019-105983RB-100/AEI/ 10.13039/501100011033) project funded by the MICINN-FEDER and the PRX21/00375 project funded by the Ministry of Universities of Spain from the “Salvador de Madariaga” programme. Manel Llena has a “Juan de la Cierva Formación” postdoctoral contract (FJC2020-043890-I/AEI/ 10.13039/501100011033) from the Spanish Ministry of Science and Innovation, while Melani Cortijos-López is working with an FPI contract (PRE2020-094509) from the Spanish Ministry of Economy and Competitiveness associated to the MANMOUNT project.  
Comparing erosion rates across timescales and processes: insights from the Western Southern Alps of New Zealand
Authors: Roda-Boluda Duna , Schildgen Taylor , Prancevic Jeff , Tofelde Stefanie , Bufe Aaron , Lupker Maarten , Wittmann Hella , Hovius Niels
Published: February 2023

Understanding the landscape evolution and potential geohazards of mountain landscapes requires quantifying the rates at which they uplift and erode, and the relative importance of different erosional processes. However, each of the available techniques to quantify rates of landscape change provides only a partial account of mountain erosion, given their inherent methodological biases and measuring timescales. Therefore, reconciling erosion and uplift rates estimated with different methods can be challenging, but can also provide insights into changes in erosion rates and dominant erosional processes.Here, we present a combination of new and compiled data from the western Southern Alps of New Zealand (WSA), one of the fastest-eroding ranges on Earth, which is believed to be in steady state. We present new data on: (a) 20 in-situ 10Be catchment-averaged denudation rates, which mostly range between ~0.6-9 mm/yr and represent erosion integrated over the last 275 years on average; (b) 17 10Be concentrations from recent landslide deposits, which together with drone photogrammetry of landslide scars, provide information about landslide recurrence intervals on millennial timescales; (c) the grain size distributions of sediment supplied from hillslopes and transported by rivers, which allows us to convert published suspended sediment load estimates (0.2-6.7 mm/yr, recorded over the 1960s-1990s) into total sediment flux estimates. Based on (b) and published landslide frequency-area data, we estimate landslide erosion rates on millennial timescales, and compare these to erosion rate estimates from (a), (c); and (d) modern published landslide erosion rates (1.8-18 mm/yr, 1948-1986), (e) published millennial soil erosion rates (up to 2.5 mm/yr), (f) compiled Late Quaternary fault throw rates (up to 12 mm/yr), and (g) recalculated thermochronological exhumation rates (up to ~6-9 mm/yr, Myr timescales).This comprehensive data set allows us to examine: (i) the proportion of total erosion driven by landslides versus other erosional processes; (ii) how modern denudation rates and landslide erosion rates compare to long-term erosion rate, rock uplift, and exhumation rate estimates; and (iii) the potential fluctuations of erosion rates and processes over seismic cycles and Holocene climate change.
Development of a spectroscopic sensor for accurate, real-time monitoring of personal exposure to nitrogen dioxide
Authors: Halpin Eibhlín F. , Venables Dean S.
Published: February 2023

Nitrogen dioxide (NO2) is a major air pollutant that can lead to increased risks of lung cancer, cardiovascular mortality, and a 50% increased likelihood of children developing asthma. Expanding the scope and range of NO2 measurements is therefore desirable to quantify NO2 levels and emissions in different settings. Current research and regulatory instruments are too expensive and bulky for widespread deployment and personal exposure measurements, while low-cost sensors do not have the required sensitivity, accuracy, and response time for many applications.Here we describe a spectroscopic, optical cavity approach to sensitively quantify NO2 based on the differential absorption at two nearby wavelengths. The system uses a modulated blue LED, an optical cavity for high absorption sensitivity, and lock-in amplification to measure the light transmitted through the cavity. Careful spectral filtering is needed to remove unwanted wavelengths. We report the system performance and Allan deviation of the system, and compare the system response against a standard IBBCEAS set-up for in situ measurements of NO2. Strategies to improve the instrument performance and reduce sensor size and cost are discussed.
Observations of the ocean waves directional spreading during the HIGHWAVE project and SUMOS campaign.
Authors: Peláez Zapata Daniel Santiago , Pakrashi Vikram , Dias Frederic
Published: February 2023

The directional distribution of ocean waves is of great importance for a better understanding of air-sea interactions. Countless applications in science and engineering, such as, offshore energy production, microseisms prediction, wave climate modelling, coastal erosion, among many others, require precise information about the wave directionality. However, in spite of its importance, this quantity is poorly understood and difficult to accurately model. This study presents observations of the directional spreading parameters obtained from a set of low-cost GPS-based buoys during highly energetic conditions. One of the buoys was anchored off the west coast of Ireland during the HIGHWAVE project. These observations are compared with the measurements of 20 freely drifting buoys deployed in the Bay of Biscay during the SUMOS campaign. Spreading parameters were compared in the framework of widely used parameterisation for the directional distribution. The directional spreading is narrower at the spectral peak and broadens as the frequency moves away towards higher and lower scales. There is a particularly sharp increase in the spreading for f < fp. The results showed that buoy-based observations significantly differ from spatial-based measurements for frequencies around half the spectral peak. The measruements obtained by the drifting buoys show that for 2 < f/fp < 6, the spreading appears to be approximately constant with the frequency and tends to increase again for f > 6fp. The results showed that the directional spreading seems to be independent of the wave age, roughly across the entire range of frequencies.  This may imply that the shape of the directional spectrum is primarily controlled by the non-linear wave-wave interactions rather by the wind forcing.  In the vicinity of the spectral peak, a weakly linear relationship between the directional spreading and the significant wave height was observed.  The results show that as the significant wave height increases by one meter, the spreading decreases by about 4.5°. The preliminary results presented here contribute to the understanding of the directional distribution of ocean waves. However, further observations and comparisons are needed to fully capture the complexity of this phenomenon. Despite being preliminary, these results provide valuable insights and add to the ongoing discussion on this topic. This work was funded by the European Research Council (ERC) under the EU Horizon 2020 research and innovation programme (grant agreement no. 833125-HIGHWAVE). We are very grateful to the scientific team behind the SUMOS campaign for providing the drifting buoys data.
Empirical approaches for quick management of cascading hazards in the Italian Alps: a warning procedure for landslide reactivation, river damming and outburst waves
Authors: Segoni Samuele , Barbadori Francesco , Gatto Alessio
Published: February 2023

Landslide hazard management usually requires time-consuming campaigns of data acquisition, elaboration, and modeling. However, in the post-emergency phase management, time is a factor, and simple but fast methods of analysis are needed to support decisions in the short-term. This paper analyzes the Theilly landslide (Western Italian Alps), which was recently affected by a series of reactivations. While some instrumental campaigns (aimed at supporting physics-based modeling and the design of effective protection measures) were still in progress, simple tools were set up to manage the hazard of future reactivations and to evaluate the possibility of damming the stream flowing at the footslope. After a detailed geomorphological survey, state-of-the-art empirical methods were customized for the specific case of study. First, a set of intensity–duration rainfall thresholds depicting increasing hazard levels is used to monitor and forecast possible reactivations. Second, in case the landslide body reaches the narrow valley at the footslope, the possible evolution scenarios (i- landslide that does not block the river; ii- river blockage with formation of a stable dam and a lake; iii- river blockage with formation of an unstable dam and release of an outburst wave) are evaluated by means of a methodology based on the hydro-morphometric characterization of the site. The proposed empirical methodologies have the advantage of requiring only ready-available input data and quick elaborations, thus allowing the rapid set up of tools that could be used for hazard management. In this case of study, these tools are being used until mitigation measures (to date, still in the project phase), are completed.
Investigating the effects of extreme rainfall trends on the flow capacity of streams over the Northeast United States
Authors: Emmanouil Stergios , Prevezianos Andreas , Langousis Andreas , Anagnostou Emmanouil N.
Published: February 2023

While various research efforts investigate the direct effects of climate change on hydrometeorological variables, the incidental consequences of extreme rainfall trends on the flow capacity of open channels remains an open question. Hydrological modeling for the assessment of flood events and the organization of protection strategies usually include precipitation fields transformed by climate change factors. The latter, however, simply account for the relation (frequently through a ratio) between past and future Intensity-Duration-Frequency (IDF) values. Along these lines, epistemic uncertainties introduced by the choice of the IDF estimation techniques and/or the extensive incorporation of climate model simulations are accounted for through the application of safety factors on the yielded results. Yet, this practice may lead to a misestimation of flood risk, accompanied by costly, yet ineffective, protective measures. Moreover, the employment of high-resolution distributed hydrological models over extensive areas can be computationally cumbersome, while introducing an additional layer of uncertainty. In this study, we attempt to link the occurrence of channel overflowing to the evolution of the magnitude and frequency of extreme rainfall over the Northeast United States. More precisely, we: a) use measured streamflow data offered by the United States Geological Survey (USGS) during the 41-year period from 1979 to 2019, to assess the rate of occurrence of flood events over gauge locations across the study domain, and b) link the observed evolution of the aforementioned overflow rates to that of extreme rainfall for different return periods and durations of temporal averaging. In this context, we attempt to develop a conceptual basis for studying the effects of climate change on the linkage between rare precipitation events and the reliability of existing channels.
Influence of Potential Vorticity Structure on North Atlantic Tropical Cyclone Activity
Authors: Lohmann Ulrike , Enz Bernhard , Neubauer David , Sprenger Michael
Published: February 2023

Tropical cyclones are among the most devastating natural phenomena that can cause severe damage when hitting land. Some of this damage could be prevented with more reliable short-term and seasonal forecasts. In the wake of the poorly forecast 2013 North Atlantic hurricane season, Rossby wave breaking has been linked to tropical cyclone activity measured by the accumulated cyclone energy. Here, ERA5 reanalysis data and HURDAT2 tropical cyclone data are used to show that the latitude of the 2 potential vorticity unit (PVU) contour on the 360 K isentropic surface in the western North Atlantic is linked to changes in vertical wind shear and relative humidity during the month of September.A more equatorward position of the 2 PVU contour is linked to an increase in vertical wind shear and a reduction in relative humidity, as manifested in an increased ventilation index, in the tropical western North Atlantic during September. The more equatorward position of the 2 PVU contour is further linked to a reduction in the number of named storms, hurricane days, hurricane lifetime, and number of tropical cyclones making landfall due to changes in genesis location. In summary, the 2 PVU contour latitude in the western North Atlantic can therefore potentially be used as a predictor in seasonal and sub-seasonal forecasting.
A global approach to defining Concurrent Atmospheric and Marine Heatwaves
Authors: Behr Lorine , Luther Niklas , Xoplaki Elena , Petalas Stamatis , Tragou Elina , Zervakis Vassilis
Published: February 2023

Atmospheric and marine heatwaves (AHW/MHW) have been observed around the world and are expected to increase in intensity and frequency under future climate change. Despite numerous studies that have examined AHW or MHW independently, only few regional studies investigated potential associations between these two types of extreme events. However, the co-occurrence of AHW and MHW could have broader and greater environmental, human, and economic impacts than an individual event, such as changes in species distributions, land and marine mass mortalities, or increased heat stress in coastal areas due to interactions between warm and moist air over the ocean. Based on research on AHW and MHW, we propose a comprehensive and globally applicable definition that relates the two extreme events and the two realms, and allows comparison with past and present concurrent and single events. Our definition is based on a conditional approach: We define a concurrent heatwave as an extreme event where sea surface temperature (SST) and 2 m air temperature (Tair) exceed their daily 90th percentiles, based on a 30-year historical baseline period, for at least 5 and 3 consecutive days, respectively (Perkins & Alexander 2013; Hobday et al. 2016). Thereby, we account for a potential lagged relationship between the two extremes by calculating and choosing the lag that provides the maximum probability of observing a MHW and an AHW simultaneously or delayed. In this work, we show the results of the most common heatwave metrics, such as duration, frequency, intensity, and cumulative intensity, for concurrent and single heatwaves in the Mediterranean Sea, Western Australia, and the Northwest Atlantic. We use SSTs from Advanced Very High-Resolution Radiometer (AVHRR) satellite data (NOAA OISST V2) as well as Tair from the ECMWF Reanalysis v5 (ERA5), both provided daily and globally on a high resolution (0.25°) for the period 1982 – 2022. In the Mediterranean Sea, we find concurrent heatwaves to be shorter and less frequent, but more intense and cumulatively intense than their single variants. For concurrent events, the MHW component (SST) is observed to be most intense in summer and spring, and the AHW component (Tair) in fall and winter. Moreover, the MHW appears to determine the strength of the concurrent heatwave in that region.
Determining the meteorological disaster of maize and soybean by machine learning algorithms with Sentinel-2 satellite images
Authors: Zeng Wenzhi , Liu Shenzhou , Huang Jiesheng
Published: February 2023

Meteorological disasters such as windstorm, waterlogging, drought and so on, are crucial factors affecting crop production and farmers’ income. Agricultural insurance is one of the important strategies to protect the interests of farmers, especially in developing countries such as China. However, the accurate identification and quantification of meteorological disasters in large scale are still difficult issues for the popularization and development of agricultural insurance. One possible solution is to combine the high-resolution remote sensing satellite images with machine learning algorithms. In this study, we conducted the measurements for the yield of soybean and maize and determined the damage degrees of about 2000 fields in 2021. The Sentinel-2 satellite images were also collected in the same or adjacent date as the field measurements. The clustering algorithm was applied to amplify the field measurements. After that, three machine learning algorithms named LightGBM, XGboost and RandomForest were used to relate the surface reflectance, crop types, disaster damage degrees, and crop yields of soybean and maize. The results indicated that the accuracy of the XGBoost algorithm is better than the LightGBM and RandomForest. In addition, the present method obtained higher accuracy for the maize than the soybean, which indicates that meteorological and image data during crop growth periods should also be added in the yield estimation process, and the differences between crop loss mechanisms of different crops should be studied in the future.