bluuebunny/crossref_metadata_2025 huggingface dataset:
A survey of the effectiveness of flood maps on flood memory and risk perception: a case study from Kelani River Basin, Sri Lanka
Authors: Perera Chamal , Nakamura Shinichiro
Published: February 2023

Flood maps are important for the floodplain communities to identify the inundation regions and to make future decisions related to their behavior. The understanding of the flood maps may vary based on several factors, including age, education, previous flood experiences, income level and the length of the residence. Based on the memory/understanding of the flood maps, the risk perception of the communities can change and it may affect the reaction against the impending disasters. The memory of the risk information provided by the flood maps decays over time and it is important to know about this decays process to initiate awareness programs at suitable intervals to increase the risk perception.To understand the effect of flood maps on the floodplain communities, a study was conducted in the Lower Kelani River Basin (LKRB), Sri Lanka. LKRB is susceptible to frequent flood conditions. Under the changing climatic conditions, the frequency and intensity of floods may further increase in future. To realize the study objectives, maps with return periods of 10-yr, 50-yr and 100-yr were distributed to a selected sample from LKRB and their understanding was assessed based on 2 interview surveys. First survey was conducted in April 2022 after the distribution of flood maps and the second survey was conducted in October 2022 with the participation of the same set of respondents. A total of 124 responses were used for the analysis. The understanding of the flood maps was evaluated based on a defined criterion. Furthermore, the risk perception of the community was assessed during the Survey 1 and 2.As per the results of the surveys, a significant decline of the memory of the flood maps was observed from Survey 1 to 2. The level of education showed a significant correlation with the memory of the flood map contents. Further, a clear improvement of the risk perception was identified during the Survey 2. The community actions and engagement following the map distribution was crucial to translate the risk perception to actual behavior.
Effects of cloud-to-water lightning strokes on open sea fish cages during eastern Mediterranean winter thunderstorms
Authors: Asfur Mustafa , Lavie Roy , Silverman Jacob , Price Colin , Korzets Menahem , Yair Yoav
Published: February 2023

Based on data obtained by the Earth Networks Total Lightning Network (ENTLN) for 5 winter seasons (DJF, 2018-2022), the flash density of lightning striking the water surface of the eastern Mediterranean Sea up to 50 km from the Israeli coastline is on average 3 strokes/km2. Out of the total lightning that strike the sea surface in the said area, about 0.05% on are superbolts with peak current > 200 kA. Cloud-to-water strikes generate thunder and underwater acoustic noise that can propagate for a few km from the strike location. While anthropogenic noises have been shown to cause negative stress responses in the marine environment and specifically in aquaculture fish cages, no stress response of cultured fish due to lightning strikes have been recorded yet.  New areas in the Israeli territorial waters are allocated to fish farms. These commercial farms will be using net cages, with high fish density expecting large yields.This research aims to find out how cultured fish respond to the acoustic noises generated by lightning strikes. This hypothesis meets a growing awareness in the aquaculture field to research fish stress that, in this case, stay trapped in the water body without the ability to effectively respond and flee lightning strikes. Continual stress of cultured fish can economically adversely affect the fish farm due to high mortality rates and decreased growth rates. By monitoring sea bream (Sparus aurata) cages, with cameras and hydrophone, during winter months of years 2021-2023, we have found several cases of stress related behavior. These cases were correlated with precise lightnings data, videos of surveillance cameras pointed toward the fish farm, audio records of underwater sound and indications of abnormal fish behavior (sudden dive or direction changes). We will present results from newly developed image processing algorithm that reads underwater fish videos files and automatically finds abnormal behavior events.
Simulating the effects of sea level rise and soil salinization on migration and adaptation in coastal Mozambique
Authors: Pandey Kushagra , de Bruijn Jens , de Moel Hans , Aerts Jeroen
Published: February 2023

Sea level rise (SLR) causes increasing salt deposition in the soil and groundwater of coastal regions. This will affect coastal farmers, since salinity levels will reduce crop yield, which leads to loss in net annual income of farmer communities. To minimize the impacts and income loss, farmers often adopt adaptation measures, such as irrigation, adding manure and gypsum, switching to salt tolerant crops, or buying less saline lands. When these options are not feasible,  farmers may migrate to inland areas to minimize future impacts and damages.We adopt an agent-based model (ABM) to simulate adaptation and migration decisions by farmers in Mozambique under sea level rise. . The ABM is coupled to a salinization module for simulating the relation between soil salinity and sea level rise. The decision rules in the model (DYNAMO-M) are grounded in economic theory of subjected expected utility where household maximize their welfare by deciding 1) to stay and face loss from salinization and flooding, 2) stay and adapt (irrigation or buy land) or 3) migrate to safer inland areas. The model runs with a yearly timestep (2020-2100) for simulating salinity levels, but accounts for dynamics in the growing season. (Future-) soil salinity levels are derived from ISRIC (2012) and Hassani et al. (2020). Projections in salinity levels are converted into (reduced-) yield levels following Maas and Hoffman (1977). Country statistics and census data are then used to estimate farmers income from expected yields. The model finally simulates adaptation decisions based on the cost (expected yield loss + adaptation investments) against the benefit (expected yield). Results show how many farming households have stayed with the damage, adapted with a measure, and migrated to inland areas over time and space.   Keywords: sea level rise, soil salinization, coastal farmers, agent-based model, migration
Concurrent Development of Benthic Storms and Bottom Mixed Layers underneath an Eddying Surface-Concentrated Zonal Jet
Authors: Chen Si-Yuan (Sean) , Marchal Olivier , Gardner Wilford
Published: February 2023

Benthic storms are episodes of strong bottom currents and sediment resuspension that occur at abyssal depths in the ocean. They are often observed in regions with strong, eddying surface currents, such as the western North Atlantic and the Argentine Basin. Deep cyclonic and anticyclonic eddies induced by surface current instabilities have been postulated to accelerate abyssal currents and generate benthic storms. Here, using a primitive-equation model with high vertical resolution, we conduct idealized numerical experiments of the unforced instability of a surface-concentrated, eastward-flowing jet in a zonal channel. We find that the jet, initially in strict thermal wind balance, becomes spontaneously unstable as a result of baroclinic instability, meanders, and eventually develops a complex eddy field with regions of strong ageostrophic flow. Associated with jet meandering, a train of cyclonic and anticyclonic eddies form along the jet and migrate in the same direction as the parent current but much slower. These eddies extend over the whole water column (4000 m depth), consistent with the tendency for eddy barotropization in geostrophic turbulence. They accelerate bottom currents, which are found to be more vigorous in a flat channel than in a channel with a meridional bottom slope. Over the course of the numerical integrations, bottom mixed layers with quasi-uniform potential temperature develop at various locations in the channel. These layers have thicknesses of O(100) m on a flat bottom and O(10) m on a sloping bottom. Our study yields preliminary insights into the fundamental role of surface current instabilities on near-bottom processes, calling for further investigations on downward energy transfer and near-bottom dissipation.
Phase-Locking between precipitation and El Niño-Southern Oscillation over northern South America
Authors: Salas Hernán D. , Poveda Germán , Mesa Óscar J. , Builes-Jaramillo Alejandro , Boers Niklas , Kurths Jürgen
Published: February 2023

We study phase-locking between the El Niño - Southern Oscillation (ENSO) and precipitation at inter-annual time scales over northern South America. To this end, we characterize the seasonality of the regional patterns of sea surface temperature, surface pressure levels, and precipitation anomalies associated with the states of the canonical ENSO. We find that the positive (negative) precipitation anomalies experienced in northern South America differ from those previously reported in the literature in some continental regions. In particular, the Orinoco Low-level Jet corridor separates two regions with negative (positive) rainfall anomalies during El Niño (La Niña), which are located in the Guianas (northeastern Amazon) and the Caribbean. Moreover, we show that the ENSO signal is phase-locked with the inter-annual rainfall variability in most of the study regions although some areas exhibit phase-locking without a significant change in the anomalies of precipitation. This suggests that ENSO could induce changes only in terms of phases and not so in terms of magnitude. This work provides new insights into the non-linear interactions between ENSO and hydro-climatic processes over the tropical Americas.
The coupling control of biological precursors and environmental factors on β-carotane enrichment in alkaline lacustrine source rocks: a case study from the Fengcheng Formation in the western Junggar Basin, NW China
Authors: Hou Maoguo , Zha Ming , Liu Hua
Published: February 2023

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation (Fm.) are typically alkaline lacustrine source rocks, which are typified by impressively abundant β-carotane. Abundant β-carotane has been well acknowledged as an effective indicator of biological sources or depositional environments. However, the coupling control of biological precursors and environmental factors on the enrichment of β-carotane in the Fengcheng Fm. remains obscure. Based on a comprehensive investigation of the bulk and molecular geochemistry of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes, we proposed a new understanding of the biological precursors of β-carotane and elucidated the coupling control of biological precursors and environmental factors on the enrichment of β-carotane in the Fengcheng Fm. The results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng Fm. The haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane, which is suggested by a good positive correlation between 7-+8- methyl heptadecanes/Cmax and β-carotane/Cmax in sedimentry rcoks and the predominance of cyanobacteria with abundant β-carotene in modern alkaline lakes. Land plants and algae do not significantly contribute to the enrichment of β-carotane, which is indicated by negative or weak correlations between terrigenous/aquatic ratio, C19 tricyclic terpene/C23 tricyclic terpene ratio, the concentration of C27 sterane, and β-carotane/Cmax. The environmental facors such as paleoclimate, paleoredox, paleosalinity, and thermal maturity are the indirect factors that control the enrichment of β-carotane by affecting the precursor supply from cyanobacteria and the preservation conditions in the Fengcheng Fm.
Sensitivity Analysis of the Noah-MP Land Surface Model for Soil Hydrothermal Simulations over the Tibetan Plateau
Authors: Hu Wei , Ma Weiqiang , Yang Zong-Liang , Xie Zhipeng
Published: February 2023

The Tibetan Plateau (TP) features unique and highly heterogeneous soils, terrains, vegetation, and climate. Accurately modeling complex freeze-thaw processes and their hydrothermal impacts remains a great challenge. This study focused on deciphering the spatiotemporal variability of diverse parameterization schemes in the soil hydrothermal simulations using the Noah-MP land surface model. We first discussed the spin-up time required by the model to reach the equilibrium state, and then performed a sensitivity analysis of these schemes. The Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature and Soil Moisture Active Passive (SMAP) remote sensing products were used as benchmarks to evaluate the schemes’ performance. Results show that longer spin-up times are required in permafrost regions owing to water phase changes. Ground temperature and soil temperature are mainly sensitive to energy-related schemes. Vegetation-related schemes play an important role after the growing season begins on the southeastern TP. Soil water content shows strong sensitivity to schemes related to both water and energy transport. However, the sensitivity of these energy-related schemes is weakened when simulating total soil moisture, including the total amount of water and ice, indicating that these schemes have marked impacts on soil freeze-thaw processes. These results reveal the different spatial (both regional and depth-related) and temporal effects of parameterization schemes; we also provided a preliminary selection of these schemes at a regional scale that could facilitate the further improvement of the soil hydrothermal simulations on the TP.
Simulation of the climate and ocean circulations in the Middle Miocene Climate Optimum by a coupled model FGOALS-g3
Authors: Wei Jilin , Liu Hailong , Zhao Yan
Published: February 2023

The warmer-than-present (5-10 ℃) climate during the Miocene Climate Optimum (MMCO, approximately 16.9-14.7 Ma) is likely to serve as a reference for the future pessimistic warming scenarios. Forced with MMCO boundary conditions, the warming and ocean circulation changes are simulated by the fully-coupled climate model FGOALS-g3. Under 400 ppmv CO2 concentration, the model generally simulates the MMCO temperature well with the small biases in the mid and low latitudes compared to proxy data. Large biases in the high latitudes show that FGOALS-g3 fails to reproduce the weak meridional gradient indicated by proxy. MMCO surface albedo decreases significantly owing to changes in worldwide forest cover in the boundary condition and the amount of sea ice melt due to the warming climate compared with the PI run. Accompanied by global ocean warming and land-sea distribution changes in MMCO, both oceanic wind-driven and thermohaline circulations strengthen. The intensified MMCO Atlantic Meridional Overturning Cell (AMOC) relative to PI is likely linked to the altered ocean-gateway configuration, particularly at low and middle latitudes. When the MMCO Panama Seaway and Tethys Seaway open, waters from the Pacific and the Indian Ocean converge and mix in the west of the North Atlantic. Joined by this water supplement (~30 Sv) from other ocean basins, the Gulf Stream enhances and flows more poleward, more heat and salinity are carried to the Subpolar North Atlantic. Consequently, the sea ice retreats and the Atlantic Meridional Overturning Cell enhances in the North Atlantic in the MMCO.
Mixing dynamics of stream water into Lake Kinneret through a short-period flow release test
Authors: Stein Shaked
Published: February 2023

The water authority of Israel has decided to create an unnatural flow starting at a point in the Tzalmon stream into Lake Kinneret (Sea of Galilee) 4 km upstream as a way to manage the lake water level. The national water company “Mekorot” use the existing national water carrier to take water from the desalination plants next to the Mediterranean Sea and transfer it to the Tzalmon river where the water will naturally flow within the stream into the lake. A test flow was conducted at changing discharge rates of 3,100, 4,500, and 6,000 m3 hour-1 for three hours for each flow rate for two days to examine the new flow system that leads desalinated water into the Tzalmon stream. Nevertheless, the test flow was a great opportunity to study the Tzalmon flow's ability to transport particles, nutrients, and bacteria as well as study their distribution dynamics in the lake. Fifteen temperature sensors were deployed in the Tzalmon river outlet to the lake to capture the mixing dynamics with the lake water during the test flow. During the flow release, profiles of temperature, electrical conductivity (EC), dissolved oxygen (DO), and pH were conducted along the flow path of the water into the lake using a boat in 5 locations. In addition, the boat sampled the water for total dissolved solids (TSS), nutrients, bacteria concentration, and general chemistry in those 5 locations in the river outlet. Along the river, six temperature sensors were deployed in and out of the water in three locations to understand the temperature change along the flow path from the discharging point to the lake. Furthermore, water samples from those 3 locations along the flow path were taken and analyzed to the above-mentioned parameters at each flow rate discharge. The results highlight the ability of the river flow to carry those parameters at different flow velocities along with their distribution dynamics in the lake water. Furthermore, the water reached the lake only at the end of the second flow period and during the third flow period due to losing conditions along the flow path. Therefore, there were only two occasions of river water mixing in the lake, and this mixing dynamic was studied and will be presented at the session. This new water discharge into an ephemeral river will start in the next few years and will change the river area ecosystem and will bring newly dissolved and solid materials into the lake. This test is the first examination of the system in which the constant flow release will potentially influence the lake ecosystem and the flow regime in the lake.
New source mechanism for airborne particulate mercury in the central Arctic
Authors: Schmale Julia , Angot Helene , Heutte Benjamin , Bergner Nora , Archer Stephen , Bariteau Ludovic , Beck Ivo , Blomquist Byron , Boyer Matthew , Frey Markus , Helmig Detlev , Howard Dean , Jacobi Hans-Werner , Jokinen Tuija , Laurila Tiia , Pernov Jakob , Posman Kevin , Pratt Kerri , Quelever Lauriane
Published: February 2023

Understanding the mercury cycle in the Arctic is important due to the harmful bioaccumulation of its toxic form, methylmercury, in wildlife and ultimately Arctic residents. Gaseous elemental mercury (Hg(0)) is relatively well-mixed across the northern hemisphere atmosphere due to its long atmospheric lifetime. Hg(0) can be oxidized, especially in the Arctic spring during halogen-driven depletion events. The resulting gaseous oxidized mercury (Hg(II)) is relatively quickly deposited onto snow, either directly or via condensing onto particles, forming particulate mercury (PHg). It is generally understood that a large fraction of the deposited Hg(II) and PHg is photoreduced to Hg(0) and re-emitted to the atmosphere. However, mercury remaining in the snowpack till melt can become bioavailable through entering the ocean.There is a severe lack of Hg(II) and PHg observations in the central Arctic, particularly over sea ice, limiting our understanding of the mercury cycle in that region and inhibiting us from quantifying mercury budgets in all environmental compartments and particularly where it unfolds its harmful neurotoxic effects. Moreover, most of the observational efforts aiming at creating process understanding focused on spring during mercury depletion events or the snow melt period, leaving large knowledge gaps for fall and winter.Here, we show atmospheric observations of PHg during MOSAiC, measured with an aerosol mass spectrometer in fall and spring over the central Arctic pack ice. In both seasons, PHg concentrations correlate strongly with wind speed and chloride, suggesting a mechanical (wind-driven) process behind atmospheric PHg related partly to blowing snow. In addition, there are significant differences between fall and spring observations (e.g. no atmospheric mercury depletion events in fall), suggesting that various processes are at play.This wind-driven process has hitherto not been reported and is different from observations at land-based stations as well as previous measurements over sea ice that ascribed the formation of PHg to adsorption of Hg(II) onto pre-existing aerosols or diamond dust rather than aerosolization from the snow pack. We hypothesize, based on snow chemical analyzes and literature, that the elevated halide content in snow on sea ice creates complexes of PHg, which are much harder to photoreduce than Hg(II), leading to a larger PHg content in snow. These processes of forming PHg and wind-driven aerosolization have implications for the mercury content of snow and the distances over which PHg is re-deposited after atmospheric transport given that the lifetime of PHg is about one order of magnitude larger than that of Hg(II) in the atmosphere. 
Atmospheric Turbulent Characteristics under Summer Shamal in Coastal Qatar
Authors: Li Yuan , Sadr Reza
Published: February 2023

Summer Shamal, a strong low-level northwesterly wind in the Middle Eastern region, is the major trigger for dust storm activity with a broad impact on regional transport and human safety. Due to the scarcity of high-frequency data, near-ground turbulent mixing analyses under Shamal are still rare. The current study investigates the near-surface turbulence characteristics of the atmospheric boundary layer (ABL) in the coastal region of Qatar under summer Shamal conditions (26.08 N, 51.36 E). The results show that, in the absence of monsoon, Shamal prevents the development of summer sea breezes in the Persian Gulf. Compared to non-Shamal days (NSD), Shamal days (SD) are characterized by higher sensible heat flux magnitude and turbulent kinetic energy (TKE) with lower humidity, especially around noon time. Turbulence stability analysis indicates the probability of different dust activities during summer SD and NSD. Wind velocity spectra are investigated to evaluate the TKE dissipation rate. A Weibull distribution is observed for PDFs of TKE dissipation rate under SD for both stable and unstable conditions.
Decarbonization and sustainable energy transition to the post-lignite era in Greece
Authors: Tagaris Efthimios , Tranoulidis Apostolos , Sotiropoulou Rafaella-Eleni P , Bithas Kostas
Published: February 2023

It has been proved that reaching the objective of complete decarbonization in Greece by the year 2028 is necessary to ensure the stability of the country's power-generating system and Greece's energy security. Since the middle of the 1960s, when lignite reserves were exploited for the purpose of power production, the Region of Western Macedonia, which includes both an industrial and an agricultural sector, has held a unique position within the borders of Greece. However, as a result of a strategy for the transition to a more sustainable energy plan, the majority of plants that were powered by lignite were required to shut down in 2019. A just transition in a post-lignite era requires strategic planning in order to avoid social, economic, and energy issues while simultaneously maximizing the amount of power output that is sustainable. The present study makes use of a SWOT analysis in order to carry out a comprehensive socio-economic analysis for the Region of Western Macedonia. This analysis takes into account all of the primary economic sectors that are present in the region that is being studied, and it discusses the priorities that have been set by the Energy Union in order to achieve its energy goals. Additionally, the study discusses the results of a generalized SWOT analysis that was applied to the specific strategy of the Energy Union, placing special emphasis on the axes requiring further support actions. According to the findings of the study, the Region of Western Macedonia possesses significant advantages and presents a multitude of fresh chances as it makes the transition to a new production model. On the other hand, its unemployment rates are quite high, and its competitiveness and innovation rates are quite poor. The difficulty to locate sufficient employment opportunities is the primary factor contributing to the desertification of the region. When taking into account the aims of the Energy Union, the Region of Western Macedonia follows the priorities of Europe in its transition to the new production model in a satisfactory manner; yet, there is a significant amount of potential for development.
Varying contributions of fast and slow responses cause asymmetric tropical rainfall change between CO2 ramp-up and ramp-down
Authors: Zhou Shijie , Huang Ping , Xie Shang-Ping , Gang Huang , Wang Lin
Published: February 2023

Tropical rainfall is important for regional climate around the globe. In a warming climate forced by rising CO2, the tropical rainfall will increase over the equatorial Pacific where sea surface warming is locally enhanced. Here, we analyze an idealized CO2 removal experiment from the Carbon Dioxide Removal Model Intercomparison Project and show that the tropical rainfall change features a stronger pattern during CO2 ramp-down than ramp-up, even under the same global mean temperature increase, such as the 2 °C goal of the Paris Agreement. The tropical rainfall during CO2 ramp-down increases over the equatorial Pacific with a southward extension, and decreases over the Pacific intertropical convergence zone and South Pacific convergence zone. The asymmetric rainfall changes between CO2 ramp-down and ramp-up result from time-varying contributions of the fast and slow oceanic responses to CO2 forcing, defined as the responses to abrupt CO2 forcing in the first 10 years and thereafter, respectively, in the abrupt-4xCO2 experiment. The fast response follows the CO2 evolution, but the slow response does not peak until 60 years after the CO2 peak. The slow response features a stronger El Niño-like pattern, as the ocean dynamical thermostat effect is suppressed under stronger subsurface warming. The delayed and stronger slow response leads to stronger tropical rainfall changes during CO2 ramp-down. Our results indicate that returning the global mean temperature increase to below a certain goal, such as 2 °C, by removing CO2, may fail to restore tropical convection distribution, with potentially devastating effects on climate worldwide.
Assessing changes in post-fire vegetation resilience in Mediterranean basin over the past 22 years
Authors: Ermitão Tiago , Gouveia Célia , Bastos Ana , Russo Ana
Published: February 2023

Fire is an integral component of ecological dynamics, playing an important role in biome distribution and biomass variability. Nonetheless, fires can also pose a  threat to both ecosystems and humans, by imposing severe economic and social consequences, and potentially contributing to biodiversity loss, carbon loss and soil erosion, whose effects can last from months to years.The Mediterranean basin is a fire-prone region where vegetation is in general well adapted to fire, with several species showing resistance to fire itself or being able to recover quickly following fire events. However, as a consequence of climate change, more intense and frequent summer hot and dry conditions are expected to occur, which can promote more frequent and severe wildfires, with return periods potentially outpacing recovery times. Understanding recovery dynamics is therefore crucial to assess the impact of changing fire regimes in ecological dynamics and stability of ecosystems. In our study, we use the “Enhanced Vegetation Index” (EVI), remotely-sensed by MODIS sensor with a temporal span of 22 years, to evaluate vegetation dynamics before, during and following large fire seasons. We use a mono-parametric recovery model to assess recovery times in different burn scars across the Mediterranean basin, covering different fire regimes and land cover types. We find a tendency for slower recovery in areas that burned more often, which may indicate a decrease in ecosystems’ resilience in the past 22 years.This study was performed under the frameworks of the 2021 FirEUrisk project (funded by European Union’s Horizon 2020 research and innovation programme under the Grant Agreement no. 101003890) and of the PhD MIT Portugal MPP2030-FCT programme (Grant no.22405886350).
Integration of deep-time databases: towards building a deep-time digital Earth
Authors: Li Haipeng , Ogg James , Quinn Daven , Scotese Christopher , Xu Honghe , Peters Shanan , Wang Jun , Zhang Linna , Hou Mingcai , Hu Linshu , Chang Sabrina , Wang Luoqi
Published: February 2023

The integration of deep-time databases is a key aspect in the creation of a comprehensive digital model of Earth's history, known as the "deep-time digital Earth." This model would enable scientists to better comprehend the intricate processes that have shaped our planet and its life forms over time. Currently, the data are dispersed across various databases and research institutions, making it challenging for scientists to fully utilize the information contained in the data.We present a virtual integration of deep-time databases, where the data remain in the sources and are accessed as needed at query time. We will demonstrate this integration using the Macrostrat, PBDB, GBDB, GeoLexicon, and the Paleogeographic Atlas Project databases. The first step involves identifying the available information from each data source and deciding on the relevant data attributes, such as lithology, age, and formation name. The next step is aligning the schemata of different data sources to a common mediated schema, allowing attribute names with the same semantics to be merged. For example, Palaeo-block in GBDB is equivalent to geoplate in PBDB. The third step is to create a virtual integration layer that allows users to access and query data from various sources as if they were stored in a single database. This virtual integration layer uses the mediated schema to translate queries and data among different sources and provides tools and interfaces for data visualization and analysis. Our goal is to make deep-time data more easily accessible and usable for a better understanding of Earth's history.
Cloud Feedback on Earth's Long-Term Climate Simulated by a Near-Global Cloud-Permitting Model
Authors: Yan Mingyu , Yang Jun , Zhang Yixiao , Huang Han
Published: February 2023

The Sun becomes brighter with time, but Earth's climate is roughly temperate for life during its long-term history; for early Earth, this is known as the faint young Sun problem (FYSP). Besides the carbonate-silicate feedback, recent researches suggest that a long-term cloud feedback may partially solve the FYSP. However, the general circulation models they used cannot resolve convection and clouds explicitly. This study re-investigates the clouds using a near-global cloud-permitting model without cumulus convection parameterization. Our results confirm that a stabilizing shortwave cloud feedback does exist, and its magnitude is ≈6 W m−2 or 14% of the energy required to offset a 20% fainter Sun than today, or ≈10 W m−2 or 16% for a 30% fainter Sun. When insolation increases and meanwhile CO2 concentration decreases, low-level clouds increase, acting to stabilize the climate by raising planetary albedo, and vice versa.
Anthropogenic aerosols turn liquid cloud droplets into ice crystals, produce snow and eat holes in the clouds
Authors: Toll Velle , Rahu Jorma , Keernik Hannes , Trofimov Heido , Voormansik Tanel , Manshausen Peter , Hung Emma , Michelson Daniel , Christensen Matthew , Post Piia , Junninen Heikki , Lohmann Ulrike , Watson-Parris Duncan , Stier Philip , Donaldson Norman , Storelvmo Trude , Kulmala Markku , Bellouin Nicolas
Published: February 2023

Living downwind of a cement-producing or a metallurgical plant could mean you get more snow, fewer clouds and more sunshine compared to nearby areas. We use satellite observations to reveal the glaciation of supercooled stratiform liquid-phase clouds by anthropogenic aerosols acting as ice-nucleating particles. There are strong indications that glaciation is caused by aerosols emitted from oil refineries, coal-fired power plants, cement, metal smelting and processing, chemical plants, and other anthropogenic air pollution sources in Europe, Asia, North America and Australia. Heavily polluted areas derived by simulating aerosol dispersion from strong anthropogenic aerosol point sources overlap with the areas of glaciation, snowfall, and decreased cloud cover strikingly well. Moreover, the polluted areas with decreased cloud cover are plume-shaped, with a distinctive head pointing towards the pollution source, similar to aerosol-polluted cloud tracks in liquid-water clouds (Toll et al 2019 Nature https://doi.org/10.1038/s41586-019-1423-9).Glaciation-induced snowfall downwind of aerosol sources is observed using ground-based precipitation radars, and tracks of snow are also seen on the ground in satellite imagery. Aerosol-induced glaciation and snowfall lead to reduced cloud cover. At multiple aerosol sources, glaciation events are more frequent than polluted tracks in liquid-phase clouds. Thus, at least locally at some aerosol sources in the middle and high latitudes, the warming effect induced by aerosols acting as ice-nucleating particles likely exceeds the cooling effect induced by aerosols acting as cloud condensation nuclei. Further research is needed to quantify the global radiative forcing by anthropogenic ice nucleating particles.
Electrical Resistivity Tomography and Ground-Penetrating Radar Measurements for Permafrost Detection on a Mountain Slope at Strandartindur, Seyðisfjörður - East Iceland
Authors: von der Esch Alexandra , Piispa Elisa Johanna , Sæmundsson Þorsteinn
Published: February 2023

In many regions of the Northern Hemisphere, permafrost is thawing due to climate change. In steep terrain, this permafrost degradation can affect slope stability. In one of Iceland's eastern fjords, Seyðisfjörður, nine major landslide cycles have occurred in the last century, originating from the lower parts (< 500 m a.s.l.) of the Strandartindur slopes, with the largest landslide event ever recorded in Iceland occurring in December 2020. Its triggering mechanism is being intensively studied and its development is being monitored. In addition to these instabilities, slow movements are also observed in the upper part (> 500 - 1010 m a.s.l.) of these slopes. In these upper areas, it is not known whether permafrost is present in the subsurface or what is causing it to creep downward. To further investigate the stability of these slopes, it is important to know and map the distribution and condition of possible permafrost layers. Therefore, electrical resistivity tomography (ERT) and ground penetrating radar (GPR) measurements were performed to study the presence and distribution of permafrost in the mountain, Strandartindur, above Seyðisfjörður. A combination of measurements is used as ERT responds primarily to the electrical resistivity of the subsurface, but this can depend strongly on other factors such as porosity, water content, etc., and GPR can help map the presence of different interfaces in the soil determined by their different physical properties, such as relative electrical permittivity, but also conductivity, which is the reciprocal of resistivity. Combining the two methods allows us to get a clearer picture of the subsurface. As a benchmark for ERT measurements in the field, a laboratory setup was performed with soil and rock samples at different temperatures and water saturations to study the behavior of frozen and non-frozen conditions in our geologic environment. With all of these measurements, we aim to answer the questions of whether permafrost is present in the selected area, what the distribution of permafrost is, whether we can use laboratory ERT to establish reference resistivity values, and if these methods are appropriate for this area.
Sequential optimization of temperature measurements to estimate groundwater-surface water interactions
Authors: Thibaut Robin , Ferré Ty , Laloy Eric , Hermans Thomas
Published: February 2023

The groundwater-surface water (GW-SW) exchange fluxes are driven by a complex interplay of subsurface processes and their interactions with surface hydrology, which have a significant impact on the water and contaminant exchanges. Due to the complexity of these systems, the accurate estimation of GW-SW fluxes is important for quantitative hydrological studies and should be based on relevant data and careful experimental design. Therefore, the effective design of monitoring networks that can identify relevant subsurface information are essential for the optimal protection of our water resources. In this study, we present novel deep learning (DL)-driven approaches for sequential and static Bayesian optimal experimental design (BOED) in the subsurface, with the goal of estimating the GW-SW exchange fluxes from a set of temperature measurements. We apply probabilistic Bayesian neural networks (PBNN) to conditional density estimation (CDE) within a BOED framework, and the predictive performance of the PBNN-based CDE model is evaluated by a custom objective function based on the Kullback-Leibler divergence to determine optimal temperature sensor locations utilizing the information gain provided by the measurements. This evaluation is used to determine the optimal sequential sampling strategy for estimating GW-SW exchange fluxes in the 1D case, and the results are compared to the static optimal sampling strategy for a 3D conceptual riverbed-aquifer model based on a real case study. Our results indicate that probabilistic DL is an effective method for estimating GW-SW fluxes from temperature data and designing efficient monitoring networks. Our proposed framework can be applied to other cases involving surface or subsurface monitoring and experimental design.
Future projection of the African easterly waves in a high-resolution AGCM
Authors: Raj Jerry , Bangalath Hamza Kunhu , Stenchikov Georgiy
Published: February 2023

African Easterly Waves (AEWs) are a significant control of West African rainfall and the associated Mesoscale Convective Systems (MCSs) and squall lines embedded within them. More than 40% of the total MCSs over the region are associated with AEWs and these MCSs account for approximately 80% of the total annual rainfall over the Sahel. Approximately 60% of all Atlantic hurricanes and 80% of major hurricanes have their genesis associated with AEWs. Simulating the features of AEWs, such as their westward propagation off the east Atlantic coast, is challenging for coarse-resolution climate models. In this study, we use High-Resolution Atmospheric Model (HiRAM) to simulate AEWs and analyze their future projections by the end of the 21st century. The simulations are performed globally at a horizontal resolution of 25km. The model uses shallow convective parameterization for moist convection and stratiform cloudiness. Future projections are conducted using representative concentration pathway 8.5. AEWs are separated with respect to their periods as 3–5 and 6–9-day period AEWs, and bandpass filtering is used to filter the waves from the mean flow. HiRAM simulates the structure and propagation of the waves well; however, it tends to overestimate the associated precipitation. In the future, the AEW precipitation and intensity of the circulation will considerably increase. The northward extent of the AEW track also shows a significant increase in the future. Enhanced baroclinic overturning and eddy available potential energy generated due to diabatic heating is also observed in the future.
Long-term dynamics of nitrogen export from European catchments
Authors: Sarrazin Fanny , Nguyen Tam , Musolff Andreas , Ebeling Pia , Batool Masooma , Sarker Paromita , Anpilova Yevheniia , Fleckenstein Jan , Attinger Sabine , Kumar Rohini
Published: February 2023

Since the beginning of the twentieth century, anthropogenic activities have severely altered the global nitrogen (N) cycle through the fixation of atmospheric N for the production of N fertilizers, the cultivation of N fixing crops, fossil fuel combustion, and the discharge of human and industrial wastewater into the environment. Both N diffuse sources (fertilizer application, biological N fixation and atmospheric N deposition) and point sources (wastewater) have led to the contamination and eutrophication of numerous water bodies worldwide and are still threatening human and aquatic ecosystem health today. This calls for both large-scale and long-term analyses of N dynamics to gain a better understanding of the changes in N export from streams in response to changes in N input following environmental policies and technological developments.In this study, we investigate the long-term dynamics of N export from European river basins over the last 70 years, which is made possible by our recent development of novel gridded datasets of long-term N diffuse sources and point sources across Europe (Batool et al., 2022). To this end, we apply the mHM hydrological model coupled with the SAS-N model (Nguyen et al., 2022). The latter accounts for possible N accumulation in the soil (biogeochemical legacy), as well as in the subsurface (hydrological legacy) utilizing water travel time via StorAge Selection (SAS) functions. We quantify N export in major European river basins (e.g. Danube, Elbe, Rhine, Rhone, Seine) accounting for the uncertainties in input data and model parameters (Sarrazin et al., 2022). We identify distinct relationships between N inputs and simulated N export, resulting from different legacy behaviours across river basins. Overall, we find a decreasing contribution of point sources to total N export over the study period, due to improvements in wastewater treatment. Through learning from the past N export dynamics, our study ultimately contributes to informing the development of future management strategies to reduce N levels below target values.Batool, M., Sarrazin, F. J., Attinger, S., Basu, N. B., Van Meter, K., & Kumar, R. (2022). Long-term annual soil nitrogen surplus across Europe (1850–2019). Sci. Data, 9, 612. https://doi.org/10.1038/s41597-022-01693-9Nguyen, T. V., Sarrazin, F. J., Ebeling, P., Musolff, A., Fleckenstein, J. H., & Kumar, R. (2022). Toward understanding of long-term nitrogen transport and retention dynamics across German catchments. Geophys. Res. Lett., 49, e2022GL100278. https://doi.org/10.1029/2022GL100278Sarrazin, F. J., Kumar, R., Basu, N. B., Musolff, A., Weber, M., Van Meter, K. J., & Attinger, S. (2022). Characterizing catchment-scale nitrogen legacies and constraining their uncertainties. Water Resour. Res., 58, e2021WR031587. https://doi.org/10.1029/2021WR031587
Using Apriori Algorithm to Find the Number of Frequent Heat Wave Days Affecting Cities in Europe Over the Future Period
Authors: Ramadoss Mahesh , Kadow Christopher , Thirunavukkarasu Meyyappan , Chellathurai Samuel , Begum Shameema , Duraisamy Narmatha , Bhadushah Akbar , Rasheed Abdul
Published: February 2023

Heatwave episodes have severe consequences in the forms of excess mortality in many regions around the world, shortage of agricultural products, drastic changes in ecosystem function and health risks. Due to the global mean temperature rising, the acceleration of extreme temperature disturbing highly at the local scale level, particularly in urban areas. From an economic growth point of view, Major cities are contributing in terms of GDP more. Heatwaves have impacted European GDP significantly in recent years. Our work is to find the number of frequent heat wave days affecting cities which are contributing to the growth of the economy in terms of GDP and density of population wise in Europe over the near future, mid future and long future using the Apriori algorithm. The features of the heat wave and their attributes have been defined according to the criteria explained in ETCCDI. The dataset that contains heat wave days in Europe derived from EURO-CORDEX climate projections is used in this work.ReferencesCopernicus Climate Change Service (C3S): Heat waves and cold spells in Europe derived from climate projections, Climate Change Service Climate Data Store (CDS),  DOI:10.24381/cds.9e7ca677
David García-León.et.al, Current and projected regional economic impacts of heatwaves in Europe, Nature Communications, https://doi.org/10.1038/s41467-021-26050-z
Christophe Lavaysse.et.al, Towards a monitoring system of temperature extremes in Europe, Nat. Hazards Earth Syst. Sci,doi:10.5194/nhess-2017-181, 2017
Chloé Prodhomme. et.al, Seasonal prediction of European summer heatwaves,https://doi.org/10.1007/s00382-021-05828-3
S. E. Perkins and L.V.Alexander, On the Measurement of Heat Waves, DOI: https://doi.org/10.1175/JCLI-D-12-00383.1
S. E. Perkins-Kirkpatrick.et.al, Changes in regional heatwave characteristics as a function increasing global temperature, DOI:10.1038/s41598-017-12520-2
Agrawal, R. and Srikant, Fast Algorithms for Mining Association Rules in Large Databases. Proceedings of the 20th International Conference on Very Large Data Bases, VLDB, Santiago de Chile, 12-15 September 1994, 487-499.
Atmospheric CO2 impact on spontaneous Dansgaard–Oeschger type oscillations: oscillatory sweet-spot for three climate models
Authors: Malmierca Vallet Irene , Sime Louise C.
Published: February 2023

Greenland ice core records feature Dansgaard–Oeschger (DO) events; abrupt warming episodes followed by a gradual cooling phase during mid-glacial periods. Here, we analysis spontaneous self-sustained D-O type oscillations reproduced in three climate models: CCSM4, MPI-ESM and HadCM3. The three models show D-O type oscillatory behaviour in a remarkably similar, narrow window of atmospheric CO2 concentrations between approximately 185 to 230 parts per million (ppm). This CO2 range also compares particularly well with Marine Isotopic Stage 3 (MIS 3 - between 27.8 – 59.4 thousand of years BP, hereafter ka) atmospheric CO2 values (∼ 233-187.5 ppm), when D-O events occurred with most regularity. Outside this CO2 window of oscillatory behaviour, two different stable states are shown in the three models; warm high CO2 (strong AMOC) and cold low CO2 (weak AMOC) states. The weak state remains stable below the first critical tipping point near 185-195 ppm and the strong state remains stable above the second tipping point near 217-230 ppm. In all three models, the oscillatory experiments with higher CO2 show an increased built-up of stadial salinity in the upper ocean in the subtropics, especially in the eastern edge of the North Atlantic Current, compared with the ensemble mean: the tendency to re-invigorate the Atlantic Meridional Overturning Circulation (AMOC) is increased and so the system spend less time in the stadial phase. CO2 also affects North Atlantic and Arctic sea ice, determining interstadial and stadial duration. Similar sensitivity CO2 experiments performed with other climate models may help in further constraining the here-identified range of atmospheric CO2 (∼185-230 ppm) bounding this D-O sweet-spot. 