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The current state of the hydrosphere is largely determined by human anthropogenic activities. Discharge of polluted waste waters into surface water bodies significantly worsens their quality and limits the possibility of safe consumption. One of the biggest sources of increasing surface waters mineralization and hardness is the discharge of spent regeneration solutions of natural waters ion-exchange softening processes, which creates a closed circulation cycle of sodium, calcium and magnesium chlorides. The necessity to reduce the intensity of this cycle and decrease environmental pollution is very actually today. The research of traditional soda-sodium softening technology has shown its low suitability for low and medium capacity systems due to necessity of water heating and subsequently pH adjusting. More acceptable solution was found in using phosphate anions as a precipitant, which ensures high efficiency in removing calcium and magnesium ions at a wide range of temperatures and pH levels. It was found that the solid phase formed during such treatment was difficult to separate from the liquid phase. Using of anionic flocculants was proposed as one of the solutions of this problem, which ensure high efficiency in separating the formed solid particles from water. Proposed technological scheme was designed for implementation as a pre-treatment stage in reverse osmosis systems of low and medium capacity. [ABSTRACT FROM AUTHOR]

Eduard Suess's invention of the word 'biosphere' sparked a trend of coining sphere-words, which has since evolved into something of a craze. Some of these words, such as atmosphere and hydrosphere, are simply name tags for their respective Earth spheres. Others, such as geosphere, are also used mainly as names but they carry more than one meaning. However, many sphere-words, including pedosphere, biosphere, ecosphere, anthroposphere, sociosphere, and technosphere, are far more than just names, bearing as they do, weighty conceptual connotations that fuel considerable debate. At a time when Earth and life scientists are attempting to understand the workings of the planet as a whole by modelling the interaction of its component spheres, and when they are collaborating with sociologists, anthropologists, and members of other human sciences to tackle current environmental challenges, it seems an opportune moment to probe the origin and meaning of words for the Earth spheres they investigate. To be sure, Earth System modelling is helping understand changes resulting from the interaction of all the Earth's spheres, including the anthroposphere, over various time and space scales, while multidisciplinary, interdisciplinary, and transdisciplinary research is helping to address such global problems as sustainable development, climate change, water supply, and biodiversity loss. An awareness of the origin, development, and disputed meanings of many sphere-words that these approaches employ should prove salutary for their multifarious practitioners. [ABSTRACT FROM AUTHOR]

The oxygen isotope ratio 18O/16O (expressed as a δ18OVSMOW value) in marine sedimentary rocks has increased by ~8‰ from the early Paleozoic to modern times. Interpretation of this trend is hindered by ambiguities in the temperature of formation of the carbonate, the δ18Oseawater, and the effects of postdepositional diagenesis. Carbonate clumped isotope measurements, a temperature proxy, offer constraints on this problem. This thermometer is thermodynamically controlled in cases where carbonate achieves an equilibrium internal distribution of isotopes and is independent of the δ18O of the water from which the carbonate grew; therefore, it has a relatively rigorous chemical-physics foundation and can be applied to settings where the δ18O of the water is not known. We apply this technique to an exceptionally well-preserved Ordovician carbonate record from the Baltic Basin and present a framework for interpreting clumped isotope results and for reconstructing past δ18Oseawater. We find that the seawater in the Ordovician had lower δ18Oseawater values than previously estimated, highlighting the need to reassess climate records based on oxygen-isotopes, particularly where interpretations are based on assumptions regarding either the δ18Oseawater or the temperature of deposition or diagenesis. We argue that an increase in δ18Oseawater contributed to the long-term rise in the δ18O of marine sedimentary rocks since the early Paleozoic. This rise might have been driven by a change in the proportion of high- versus low-temperature water-rock interaction in the earth's hydrosphere as a whole. [ABSTRACT FROM AUTHOR]

Under the Programme of integrated teacher education not a single study is recommended, the study of fish and fisheries is recommended with the study of fresh water pollution. This type study may be integrated with the study of Earth and Earth's layers of Atmosphere, Hydrosphere and Lithosphere. Pollutants are spreaded by any source in the air, soil and water. The Pollution may represent as Air pollution, water pollution and soil pollutions. The pollution is named as per their availability:- Air pollution water Pollution and Land Pollution, Land and Air Pollutants may be dissolved in water, to produce more harmful effects on the life of fishes. [ABSTRACT FROM AUTHOR]

The Euler’s holomorphic regenerative universe is a quantum-gravitational theory of Earth development recognizing that oxygen, hydrogen, nitrogen and carbon dioxide in the Earth’s hydrosphere engender biological processes along with living organisms able to reshape the planet as surely as any physical force, but with delayed effects, the so-called torsional/gravitational buckling lag. Herein, the environmental sciences as a Vernadsky’s hypothesis precursor to these, become vital for preserving biological recurrent cycles, their nature being artificially changed by a vicious human intervention. The present paper describes the thermal gravitational mechanism of a solar system associated with the regenerative processes of molecular structures (in biology called metabolism or growth) at the quantum-gravitational scale, too slow to be perceived. The term “morph” (or the concept of “morphing” in aeronautics, in mathematics called topological holomorphism) originates from ancient Greeks and refers to the shape, figure, or other related aspects of an evolving entity. Therefore, morphing/morphism pertains to the process of modifying the original form or appearance of a particular object or system. The planets of solar system like “cosmic organisms” can manipulate the curvature and twist of their surfaces to maintain precise control over their recurrent cyclical complex motions (double, orbital and sideral rotations) by the thermal gravitational waves. The out of order function of the thermal gravitational mechanism can lead to the global warming effects associated with both reshaping (earthquakes, fires, floods) surfaces and morphing (as a whole energy metabolism) mutations, crucial for perpetuity of human beings. At the same time, the concept of quantum-gravity light with a topological dual isomorphic structure solves the fundamental problem of a unified theory of physical forces, as kinematic fast dynamo electromagnetic forces for splitting quanta bonded into atomic structures, and persistent (long time) gravitational forces for non-splitting quanta bonded into thermomolecular morphing structures. The only problem remains to gauge such multiple cooperative physical phenomena induced by light, which is solved by diverse reciprocity/equivalence theorems and corresponding conversion factors. [ABSTRACT FROM AUTHOR]

The elevations of water surfaces hold important information on the earth's oceans and land surface waters. Ocean sea surface height is related to the internal change of the ocean's density and mass associated with ocean circulation and its response to climate change. The flow rates of rivers and volume changes of lakes are crucial to freshwater supplies and the hazards of floods and drought resulting from extreme weather and climate events. The Surface Water and Ocean Topography (SWOT) Mission is a new satellite using advanced radar technology to make headway in observing the variability of the elevation of water surfaces globally, providing fundamentally new information previously not available to the study of earth's waters. Here, we provide the first results of SWOT over oceans, rivers, and lakes. We demonstrate the potential of the mission to address science questions in oceanography and hydrology. Plain Language Summary: Earth is a water planet. The vast amount of ocean water has stored most of the heat released to the atmosphere since the Industrial Revolution through burning fossil fuels. Climate change is thus moderated by the ocean. Over land the freshwater in lakes, rivers, and reservoirs, a critical natural resource, is affected by the warming climate and direct human modifications. Processes of oceanic uptake of heat and carbon from the atmosphere and cycling of freshwater on land take place at spatial scales too small to have been adequately quantified from space. A new satellite, the Surface Water and Ocean Topography (SWOT) mission, was launched in December 2022. Using advanced radar technology, SWOT provides unprecedented global observations for understanding the ocean's role in climate change and how freshwater resources respond to human influence. SWOT observations near coasts will also advance understanding of how rising sea levels impact those coasts. Key Points: The first space observations of submesoscale ocean surface topography for understanding ocean's role in heat uptake from the atmosphereThe first space observations of the change of water storage of lakes and flow rates of rivers for understanding the freshwater cycleThe first space observations of the details of the change of coastal water levels to assess the impact of local sea level rise [ABSTRACT FROM AUTHOR]

The global surface mass variations obtained by the Gravity Recovery and Climate Experiment (GRACE) satellite Level-2 products show significant north-south strip noise, which seriously affects the estimation of regional surface mass variations. Most existing filtering methods are based on the processing of spherical harmonic basis functions to remove stripes. However, because spherical harmonic basis functions are only orthogonal globally, they may not be orthogonal in regions, which hinders the effective constraint of quality changes in specific regions. Therefore, this paper converts the spherical harmonic base of GRACE Level-2 to the Slepian base of the interested region and truncates it based on the Shannon number of the region. Even though the signals are concentrated in the region, there are still many stripes present. In order to remove the stripes, it is necessary to introduce the regularization and consider the statistical information of the spherical harmonic coefficient. The Tikhonov regularization matrix of the Slepian coefficient is obtained, combined with a power-law model to construct the prior covariance matrix of the signal and the optimal regularization coefficient is selected by using the generalized cross-validation (GCV) method, which is represented as the statistically optimal Slepian method (SO-Slepian) in this study. The results show that the ability of SO-Slepian and decorrelation and denoising Kernel (DDK) filtering with the same regularization parameters as SO-Slepian to remove stripes and retain signals in the selected region is comparable. The line chart comparing the differences between SO-Slepian and DDK not only demonstrates the close similarity in results between SO- Slepian and traditional DDK filtering in the regional domain but also emphasizes the logical application of regularization during the Slepian modeling stage. It further supports the rationality of developing a regularization scheme for GRACE data processing based on Slepian. [ABSTRACT FROM AUTHOR]

Microseism is the continuous background seismic signal caused by the interaction between the atmosphere, the hydrosphere and the solid Earth. Several studies have dealt with the relationship between microseisms and the tropical cyclones, but none focused on the small-scale tropical cyclones that occur in the Mediterranean Sea, called Medicanes. In this work, we analysed the Medicane Apollo which impacted the eastern part of Sicily during the period 25 October–5 November 2021 causing heavy rainfall, strong wind gusts and violent sea waves. We investigated the microseism accompanying this extreme Mediterranean weather event, and its relationship with the sea state retrieved from hindcast maps and wave buoys. The spectral and amplitude analyses showed the space–time variation of the microseism amplitude. In addition, we tracked the position of Apollo during the time using two different methods: (i) a grid search method; (ii) an array analysis. We obtained a good match between the real position of Apollo and the location constraint by both methods. This work shows that it is possible to extract information on Medicanes from microseisms for both research and monitoring purposes. [ABSTRACT FROM AUTHOR]

Building on recent work identifying how the infrastructures of human social and economic life themselves depend on the "natural infrastructure" of biogeochemical systems, I explore the idea that infrastructuring - involving causal relations between subsystems operating at different timescales - might be a strategy widely adopted by matter undergoing self-organization under planetary conditions. I analyze the concept of infrastructure as it is used to describe features of the human "technosphere" and identify the importance of a difference in timescales between supporting and supported structures and processes. I explore some examples of how the wider planet might be said to engage in timescale-distancing and infrastructuring, focusing in particular on examples from the hydrosphere and biosphere. I then turn to the question of how to explain infrastructuring, developing a neocybernetic account of infrastructuring as involving the separation of a system into subsystems at different timescales in mutual but asymmetrical causal relations. I conclude by exploring the implications of this approach for the way we think about planets in general and the human technosphere. [ABSTRACT FROM AUTHOR]

This paper presents the Cameron Aquatic Projection, a novel concept designed to depict the world's surface hydrosphere as it is, a continuous unbroken unit including oceans and rivers. After a review of related past projections, the paper will describe the parameters of the projection, according to the existing layout of surface water on Planet Earth. This description of the design principles is followed by the mathematical realization of the proposal. The article concludes with completed examples of the projection and suggests future applications. [ABSTRACT FROM AUTHOR]

Exploration of the solar system has revealed multiple worlds that may host extensive liquid water oceans beneath kilometers of ice. These worlds offer compelling targets in a search for evidence of life beyond Earth. Our understanding of the physics, chemistry, and geology of Earth’s hydrosphere provides essential interpretive context for the initial observations made of these other ocean worlds. As further exploration turns increasingly toward life detection, we can find similar context in our understanding of the biology of Earth’s ocean and leverage the technologies and observing strategies that underlie it. [ABSTRACT FROM AUTHOR]

Sources of formation of environmental hazards in the Technosphere are industrial facilities and other objects of economic activity. The danger lies in the transformation of elements of the natural subsystem, and in the impact on humans. Man-made impact contributes to the emergence and accumulation of environmental hazards in the environment. The type of technological process, the frequency of its action and the intensity of man-made factors contribute to the appearance of manifestations of environmental danger, which puts before society the need to study the state of this danger and ways to eliminate it. Determining the real state of human environmental safety and the natural environment under the influence of factors of contamination of soil and hydrosphere waste from electroplating production with harmful and dangerous substances is a problem today. The economic complex of the electronic and radio engineering industry plays an essential role in the formation of the city's environmental hazard. These enterprises are the main sources of environmental hazards, the priority among which is the type of hazard caused by chemical factors affecting the environment. Liquid and solid waste in their storage areas on the territory of enterprises creates an environmental hazard, since harmful substances contained in them pollute soils, open reservoirs, and underground aquifers. Heavy metal ions found in sludge and taken to landfills can form water-soluble complex compounds and create an environmental hazard, which manifests itself in contamination of soils and underground aquifers. All of the above causes a problem that needs to be solved in order to significantly limit the formation of sludge during the production of printed circuit boards and the use of electroplating processes, which will make it possible to reduce environmental hazards. One of the serious, unresolved and constantly increasing problems is the problem of solid waste: its quantity is constantly growing, the composition is becoming more diverse, there are not enough territories for their placement, and the cost of their disposal is increasing. It should be noted that the problem of solid waste has long turned from a purely ecological one into a socio-ecological one: solid waste is not only a significant factor in pollution of the air Environment, Water Resources, soil and other natural components, but also the cause of a decrease in the quality of life, which is manifested in an increase in the incidence of diseases of the population, a decrease in income, deterioration of working and Recreation conditions. Solid waste management within the framework of socio-economic policy directly affects the development of the region. A special feature of Solid Waste Management is that this process is initiated simultaneously at different levels of management: from state to local (level of an economic entity). [ABSTRACT FROM AUTHOR]

Rare earths and yttrium (REY) distribution patterns of the hydrosphere reveal systematic correlations of Gd and Y anomalies besides the non-correlated redox-dependent Ce and Eu anomalies. Eu anomalies are inherited by dissolution of feldspars in igneous rocks, whereas Ce, Gd and Y anomalies develop in aqueous systems in contact with minerals and amorphous matter. Natural, positive Gd and Y anomalies in REY patterns characterize high-salinity fluids from the Dead Sea, Israel/Jordan, the Great Salt Lake, USA, the Aral Sea, Kazakhstan/Uzbekistan, ground- and surface water worldwide. Extreme Gd anomalies mostly originate from anthropogenic sources. The correlation of Gd and Y anomalies at low temperature in water bodies differ from geothermal ones. In nature, dynamic systems prevail in which either solids settle in water columns or water moves through permeable sediments or sedimentary rocks. In both cases, the anomalies in water develop due to repeated equilibration with solid matter. Thus, these anomalies provide information about the hydrological history of seawater, fresh groundwater and continental brines. When migrating, the interaction of aqueous phases with mineral surfaces leads to increasing anomalies because the more hydrophillic Gd and Y preferentially remain in the aqueous phase compared to their nearest neighbors. The correlation coefficients between Gd and Y anomalies in groundwater is 0.5-0.9. In lakes and oceans, it is about 0.1-0.8, under anomalous conditions it can increase to 1. [ABSTRACT FROM AUTHOR]

Let us consider Earth and the community of planets as seeds broadcast into a field - in this case, a solar field. Earth and Water We know that Earth, like other planets of the early solar system, formed from the accumulation of material surrounding our Sun. Scholars suggested there was dry land because the earth sphere floated like an apple in the water sphere, or that God miraculously held back the oceans. [Extracted from the article]

Long‐term monitoring of global mass transport within the Earth system improves our ability to mitigate natural hazards and better understand their relations to climate change. Satellite gravity is widely used to monitor surface mass variations for its unprecedented spatial and temporal coverage. However, the gravity data contain signals from visco‐elastic deformation in response to past ice sheet melting, preventing us from extracting signals of present‐day surface mass trend (PDMT) directly. Here we present a global inversion scheme that separates PDMT and visco‐elastic glacial isostatic adjustment (GIA) signatures by combining satellite gravimetry with satellite altimetry and ground observations. Our inversion provides global dual data coverage that enables a robust separation of PDMT and GIA spherical harmonic coefficients. It has the advantage of providing estimates of Earth's long wavelength deformation signatures and their uncertainties. Our GIA result, along with its uncertainty estimates, can be used in future GRACE processing to better assess the impact of GIA on surface mass change. Our GIA estimates include a rapid GIA uplift in the Southeast Alaska and the Amundsen Sea Embayment, due to the visco‐elastic response to recent glacial unloading. We estimate the average surface mass change rate from 2002–2010 to be −203 ± 3 GT·a−1 in Greenland, −126 ± 18 GT·a−1 in Antarctica and, −62 ± 5 GT·a−1 in Alaska. The GIA low degree spherical harmonic coefficients are sensitive to rheological properties in Earth's deep interior. Our low‐degree GIA estimates include geocenter motion and J˙2 which provide unique constraints to understand Earth's lower mantle and ice history. Plain Language Summary: Surface mass exchange between Earth's "spheres"—atmosphere, hydrosphere, cryosphere, biosphere, and pedosphere— are enormous. Monitoring surface mass change helps to understand climate change and mitigate hazardous effects such as extreme drought or flooding. Measurements of surface mass change are perturbed by subsurface processes, such as mantle flow underneath Earth's crust. Often, a model is used to correct the subsurface signals from observations, and likely to introduce un‐modeled process errors into the surface mass estimates. We use a mostly data‐driven method to extract present‐day surface mass change trends along with their error estimates. The results give an enhanced view of the surface mass processes and can help improving the accuracy of future surface mass estimations. Moreover, we get a more accurate picture of the subsurface processes, that are mainly caused by Earth's viscous response to past ice sheet melting. We find that Earth's crust bounces back more rapidly after glacier melting events than we assumed before, especially in places where the mantle viscosity is low. Key Points: Separation of present‐day mass transport and glacier isostatic adjustment signatures using multiple observation typesEstimation of geocenter motion due to past and present‐day surface mass changesEnhanced glacial isostatic adjustment signals detected in areas of low upper mantle viscosity and recent ice loss [ABSTRACT FROM AUTHOR]

Hydrogen and deuterium isotopic evidence indicates that the source of terrestrial water was mostly meteorites, with additional influx from nebula gas during accretion. There are two Earth models, with large (7–12 ocean masses) and small (1–4 ocean masses) water budgets that can explain the geochemical, cosmochemical, and geological observations. Geophysical and mineral physics data indicate that the upper and lower mantles are generally dry, whereas the mantle transition zone is wetter, with heterogeneous water distribution. Subducting slabs are a source of water influx, and there are three major sites of deep dehydration: the base of the upper mantle, and the top and bottom of the lower mantle in addition to slabs in the shallow upper mantle. Hydrated regions surround these dehydration sites. The core may be a hidden reservoir of hydrogen under the large water budget model. Earth is a water planet. Where and when was water delivered, and how much? How does water circulate in Earth? This review looks at the current answers to these fundamental questions. [ABSTRACT FROM AUTHOR]

Based on the most active hydrosphere on the earth, the interplay between adjacent semiconducting minerals and electrochemically active microorganisms was scientifically researched in the marine euphotic zone of the Yellow Sea, China. Fe and Ti were found in suspended minerals by ICP-MS and EDS, probing the element composition of suspended minerals from macro to micro. Moreover, SR-XRD and Raman indicated that semiconducting minerals of iron and titanium metal oxide in situ such as anatase, rutile, brookite, and goethite consisted in suspended minerals, notably, which retained prominent photo-response property and distinct photoelectric catalytic potential under visible light. 16S rRNA gene systematically emerged that electrochemically active microorganisms, such as Pseudomonas and Paraclostridium, were pivotal in the solution and preponderant on the electrode respectively after a period of cultivation. Whereupon a dual-chamber reactor was established to probe into the mechanism of redox reaction and electron transfer process between microorganisms and suspended minerals. Importantly, compared with a graphite electrode, the maximum power density of the reaction was 2.78 times with the increase of suspended minerals as the electron acceptor under dark conditions, as well as 236.53% promotion with visible light. Experiments gave an index that semiconducting minerals could interact with electroactive microorganisms, effectively promoting the process of extracellular electron transfer in the euphotic zone, which will make a foundation for further research on electron energy transfer based on the interactions of semiconducting minerals and electrochemically active microorganisms, as well as the regulation mechanism of elements cycling. [ABSTRACT FROM AUTHOR]

The Gravity Recovery and Climate Experiment (GRACE) mission has enabled mass changes and transports in the hydrosphere, cryosphere and oceans to be quantified with unprecedented resolution. However, while this legacy is currently being continued with the GRACE Follow-On (GRACE-FO) mission there is a gap of 11 months between the end of GRACE and the start of GRACE-FO which must be addressed. Here we bridge the gap by combining time-variable, low-resolution gravity models derived from European Space Agency's Swarm satellites with the dominating spatial modes of mass variability obtained from GRACE. We show that the noise inherent in unconstrained Swarm gravity solutions is greatly reduced, that basin averages can have root mean square errors reduced to the order of cm of equivalent water height, and that useful information can be retrieved for basins as small as 1000 × 1000 km . It is found that Swarm data contains sufficient information to inform the leading three global mass modes found in GRACE at the least. By comparing monthly reconstructed maps to GRACE data from December 2013 to June 2017, we suggest the uncertainty of these maps to be 2 - 3 cm of equivalent water height. [ABSTRACT FROM AUTHOR]

One of the requirements for inferring mantle redox states via zircon Ce/Ce* oxybarometry and Ti‐in‐zircon thermometry is to select mantle‐equilibrated zircon derived from melts that have not interacted with the hydrosphere nor assimilated exogenous materials. Traditional protocols for identifying mantle‐equilibrated zircon require a comprehensive examination of whole rock geochemistry in addition to zircon morphology, texture, and trace element and isotopic measurements. This study proposes a simple filter scheme for selecting mantle‐equilibrated zircon using trace element systematics alone (P, Ti, Y, Nb, rare earth elements [REE], Hf, Th, and U) to provide the geological context of zircon from three perspectives: (1) mineral inclusions; (2) source melt petrogenesis; and (3) zircon saturation context. The filter scheme presented here, comprising of 13 criteria, is established based on detailed classifications of 2,173 zircon analyses from 30 independent references and is shown to distinguish between nonmagmatic zircon, magmatic zircon with significant inclusions and/or sourced from highly enriched source melts, and mantle‐equilibrated zircon. The filter scheme is validated with known, well‐characterized mantle‐equilibrated Jack Hills zircon (n = 53) and derives an average mantle redox state of ΔFMQ1.5±1.3 (sd) circa 4,400 Ma, in agreement with previously published results. Further application of the filter scheme to zircon dataset (n = 76) from three metasedimentary rocks successfully reveals the mantle‐equilibrated zircon in the dataset, and implies a mantle redox state of ΔFMQ−1.5±1.3 (sd) circa 2,950 Ma. This filter scheme can be applied to studies of out‐of‐context detrital and/or xenocrystic zircon in the future. Plain Language Summary: Zircon is a robust accessory mineral commonly found in felsic rocks. The Ce/Ce* and Ti content in zircon can be used to infer the redox states of local magmatic environments from which they crystallized. Importantly, only mantle‐equilibrated zircon (i.e., unaltered magmatic zircon that crystallized from melts without interaction to the hydrosphere nor assimilated exogenous materials) record the chemistry of mantle source, and provide insights of mantle redox state via zircon Ce/Ce* oxybarometry and Ti‐in‐zircon thermometry. Traditionally, the identification of mantle‐equilibrated samples has relied on comprehensive examination of zircon and their host rocks (i.e., whole rock geochemistry, zircon morphology, texture, and trace element and isotopic measurements) in order to obtain information for zircon saturation context, source melt petrogenesis, and postmagmatic history. This study, however, presents a simple filter scheme that facilitates the selection of mantle‐equilibrated zircon and provides insights about zircon petrogenesis using trace element systematics alone (P, Ti, Y, Nb, REE, Hf, Th, and U). Key Points: This study has established a multidimensional filter scheme to select mantle‐equilibrated zircon using trace element chemistry aloneThe local melt redox states have been estimated from zircon using Ti‐in‐zircon thermometry and Ce/Ce* oxybarometryThis proposed filter scheme has been validated with external datasets and derived mantle redox states around ΔFMQ since the early Earth [ABSTRACT FROM AUTHOR]

The Mont-Blanc massif, being iconic with its large glaciers and peaks of over 4,000 m, will experience a sharp increase in summer temperatures during the twenty-first century. By 2100, the impact of climate change on the cryosphere and hydrosphere in the Alps is expected to lead to a decrease in annual river discharge. In this work, we modelled the twenty-first century evolution of runoff in the Arve river, downstream of Mont-Blanc's French side. For the first time for this region, we have forced a hydrological model with output from an ice-dynamical glacier model and 16 downscaled climate projections, under RCP4.5 and RCP8.5 scenarios. By 2100, under RCP8.5 (high-emission scenario), the winter discharge of the Arve river remains low but is expected to increase by 80% when compared to the beginning of the century. By contrast, the summer season, currently the most important discharge period, will be marked by a runoff decrease of approximately 40%. These changes are almost similar according to a scenario with a lower warming (RCP4.5) and are mostly driven by glacier retreat. These shifts will have significant downstream impacts on water quantity and quality, affecting hydroelectric generation, agriculture, forestry, tourism and aquatic ecosystems. [ABSTRACT FROM AUTHOR]

The presence of a planetary magnetic field is an important ingredient for habitability. The coexistence of a solid and a liquid core can facilitate the maintenance of a compositionally driven dynamo; however, the likelihood of such a configuration in super‐Earths is unknown. Recently, shock experiments and ab initio calculations have constrained the stability, equations of state, and melting properties of ultrahigh pressure core and mantle phases. Here, we investigate the internal structure of super‐Earth exoplanets with a range of total masses and core mass fractions ranging from that of Mars (0.2) to Mercury (0.68), including an Earth‐like bulk composition. We examine the effect of the initial core‐mantle boundary temperature (TCMB) on their internal structure and identify regimes with coexisting solid and liquid cores, and deep mantle melting. We find that the range of TCMB for which an inner core is growing increases with the total planet mass and even more with the core mass fraction. Therefore, our results suggest that super‐Earths should have a crystallizing core over a large temperature range. We also find that the presence of a growing inner core is likely to be accompanied by a partially liquid lower mantle, which will likely influence planetary thermal evolution. We estimate the initial CMB temperature after super‐Earth accretion by assuming an accretional heat retention efficiency similar to Earth. We find that massive super‐Earths are expected to have an initial internal temperature consistent with a partially liquid core, allowing for the possibility of thermal and compositional dynamo action. Plain Language Summary: The presence of a magnetic field in a planetary body is an important criterion for habitability, since it may reduce atmospheric loss and shield planetary surfaces from high‐energy charged particles. In terrestrial planets, when an inner iron‐rich core crystallizes, it releases light elements in the residual liquid outer core, which can facilitate liquid iron alloy convection and contribute to the maintenance of a magnetic field. In this study, we investigate the optimal conditions for the presence of a crystallizing core in super‐Earths (i.e., large rocky exoplanets), by modeling their internal structure and using recent data on the melting properties of materials at ultrahigh pressure. We find that cores of super‐Earths of large sizes have a greater likelihood to be partially molten, which may aid in maintaining a magnetic field. In addition, the lowermost mantle of massive super‐Earths are likely to experience prolonged partial melting. Increasing the size of their core relative to their mantle increases even more the probability of a growing inner core. In addition, we calculate the initial heat retained during planetary formation, which confirms that large super‐Earths are likely to have an initial crystallizing core. Key Points: We modeled the internal structure of super‐Earths and investigated the likelihood that an inner core existsSuper‐Earths with a large core have a wide range of temperature at the core mantle boundary over which a solid and a liquid core coexistIncreasing the size of super‐Earths iron core increases the likelihood of maintaining an inner core and deep mantle melting [ABSTRACT FROM AUTHOR]

In many respects, the field of environmental soil chemistry has never been more important than today. Permafrost soils sequester 1035 petagrams (Pg) of carbon (C) [[9]] in the top 3 m of soil, which represents about 70% of the current estimate for global soil C storage in the top 3 m (1500 Pg C) [[10]]. It is critical to understand the role of warming in release of C, particularly C that is complexed with soil minerals such as iron oxides, which are major components for sequestering soil carbon [[16]-[20]]. Major decadal research thrusts in environmental soil chemistry In view of the above environmental challenges, it seems clear that the major research frontiers in environmental soil chemistry over the next 5-10 years will be heavily focused on the impacts of climate change on various soil chemical and mineralogical reactions and processes. [Extracted from the article]

Observations taken over the last few decades indicate that dramatic changes are occurring in the Arctic-Boreal Zone (ABZ), which are having significant impacts on ABZ inhabitants, infrastructure, flora and fauna, and economies. While suitable for detecting overall change, the current capability is inadequate for systematic monitoring and for improving process-based and large-scale understanding of the integrated components of the ABZ, which includes the cryosphere, biosphere, hydrosphere, and atmosphere. Such knowledge will lead to improvements in Earth system models, enabling more accurate prediction of future changes and development of informed adaptation and mitigation strategies. In this article, we review the strengths and limitations of current space-based observational capabilities for several important ABZ components and make recommendations for improving upon these current capabilities. We recommend an interdisciplinary and stepwise approach to develop a comprehensive ABZ Observing Network (ABZ-ON), beginning with an initial focus on observing networks designed to gain process-based understanding for individual ABZ components and systems that can then serve as the building blocks for a comprehensive ABZ-ON. [ABSTRACT FROM AUTHOR]

To investigate the effect of CO2 on water solubility in orthopyroxene coexisting with H2O-CO2 as a buffering fluid, high-pressure experiments were conducted at pressures of 1.5 and 3 GPa and a temperature of 1100 °C. The experiments were performed in a Walker-type multianvil assembly using natural orthopyroxene with various CO2 to CO2-H2O molar ratios as a starting material. The water contents were measured by polarized Fourier transform infrared spectrometry. At 1.5 GPa and 1100 °C, the H2O solubility decreased with increasing CO2 content in the fluid. The water solubility c(H2O) could be quantitatively determined based on water fugacity f(H2O) as c(H2O) = 25.21 × f(H2O)1.24. The addition of 57% CO2 dramatically reduced the water solubility in orthopyroxene from 184 to 90 ppm. In contrast, at 3 GPa and 1100 °C, the water solubility did not change with the CO2 content in the starting material because CO2 is unstable in bulk peridotite due to the reaction between CO2 and olivine at pressures exceeding 2.2 GPa. This study confirms that the additional component in the aqueous fluid can change the water activity and fugacity, thereby directly lowering the water storage capacity in mantle minerals. As a result, previous estimates of the maximum water storage capacity in the shallow mantle may be overestimated by a factor of 3. [ABSTRACT FROM AUTHOR]

Current studies in global mean sea level, GMSL, studies assess the closure/misclosure of the GMSL budget components and their uncertainties. Because Earth's hydrosphere conserves water, a closed global mean sea level budget with a consistent set of estimates and their statistics is necessary. An unclosed budget means that there are problems to be addressed such as biases in the budget components, unreliable error statistics about the estimates, unknown or known but unmodeled budget components. In a misclosed global mean sea level budget, as practiced in recent studies, the trend estimates for the budget components and their errors account only for the anomalies of each budget component in isolation. On the other hand, the trend of each series must consider the trends of the other series in tandem such that the global mean sea level budget is closed for a holistic assessment, which can only be achieved by adjusting global mean sea level budget components simultaneously. In this study, we demonstrate a statistical protocol to ameliorate this deficiency, which potentially have implications for future sea level science studies, including the future Intergovernmental Panel on Climate Change (IPCC) Assessment Reports, and the US Climate Assessment Reports. [ABSTRACT FROM AUTHOR]

At seasonal and shorter time scales, polar motion and length‐of‐day (LOD) change are dominated by mass redistribution in the Earth climate system, including the atmosphere, oceans, and hydrosphere. Long‐term polar motion and LOD change are believed to be forced by solid Earth geophysical process, such as glacial isostatic adjustment. Decadal LOD variations are also connected to core‐mantle coupling. This study provides a comprehensive analysis of interannual oscillations in all three components of Earth rotation using accurately measured polar motion and LOD time series, and geophysical excitations computed from atmospheric, oceanic, and hydrological models over the period 1962 to 2018. Strong interannual oscillations remain in all three components after detrending and band‐pass filtering to retain variations at periods between 2 and 8 years. Polar motion Y is dominated by a 3.65‐year oscillation, plus others at periods of 2.5 and 5.9 years. Polar motion X shows a strong oscillation near 5.9 years, plus smaller variations at shorter periods. A 5.9‐year LOD variation has been recognized in earlier studies, but oscillations at periods of 2.36, 3.65, and 4.9 years are also observed. Atmosphere, ocean, and hydrosphere (AOH) sources largely account for 2.5‐ and 3.65‐year components in polar motion Y, but not for the 5.9‐year component in polar motion X and Y. The 2.36‐, 3.65‐, and 4.9‐year components in LOD can largely be accounted for by AOH sources. The 5.9‐year LOD component becomes more prominent after AOH sources have been subtracted. The presence of a 5.9‐year variation in all three components of Earth rotation suggests a source in Earth's interior, probably from the core. Key Points: We provide a comprehensive analysis of interannual oscillations in all three components of Earth rotation over the period 1962–2018This is the first study to have identified a 5.9‐year oscillation in all three components of Earth rotation, polar motion (X and Y), and LODThe presence of a 5.9‐year variation in all three components of Earth rotation suggests a source from the core and mantle [ABSTRACT FROM AUTHOR]

We use numerical integration of Brzeziński's broad-band Liouville equations with the new atmospheric/oceanic excitations provided by GFZ Potsdam to calculate their effect on polar motion. There exist several studies hinting that geomagnetic jerks, sudden changes of intensity of geomagnetic field, can also affect polar motion. We concentrate our efforts to study possible influence of geomagnetic jerks on temporal changes of polar motion. We demonstrate that the fit between integrated and polar motion observed by space geodesy improves substantially, if the influence of geomagnetic jerks is added to excitations by geophysical fluids. We also applied additional excitations due to the continental hydrosphere and barystatic sea-level variations. Although these effects complete the geophysical fluids system, their adding could not improve the agreement between integrated and observed polar motion. [ABSTRACT FROM AUTHOR]

Principles of the world origin and structure in relation to the Mendeleev's periodic law are presented in this paper. Our Universe consisting of hydrogen (88.6%), helium (11.3%), and other chemical elements (0.1%) has created very favorable conditions for life on the Earth, including the much-needed water—a unique substance with all its anomalies. Special attention is given to hydrogen, the first element of the periodic table, from which the formation of our solar system began. Moreover, hydrogen is a basic building material for all the other elements. It is shown that a fundamentally important fact implies that all the worlds consist of the same chemical elements of the periodic table; today the total number of the known elements in this table amounts to 118, including the artificially produced ones. There are no new elements in the Universe. And herein lies the genius of Mendeleev as the author of the periodic law and the whole grandeur of the law of understanding the world, in which the humanity lives, making it possible to predict the existence of new planets and the existence of unknown chemical elements in the periodic table that were not discovered earlier. The second unique substance on planet Earth is water, because it can simultaneously exist in three phase states: liquid, solid and gaseous with a multitude of various physical, biological and other anomalies violating the generally accepted laws of nature, but owing to which life exists on our planet. Indeed, it is just the entropy changes of the process that make a decisive contribution to all energy characteristics of transformation of some substances into others. The essence of all chemical processes occurring on earth in accordance with the laws of non-equilibrium thermodynamics consists in an infinite sequence of self-organization processes. Due to these laws, new types of structures can spontaneously arise that are characterized by a transition from chaos and disorder to the order and strict organization. Despite an enormous progress in the study of the Universe, its structure remains to be no less mysterious. It remains to find scientific evidence that there is a Supreme Being that generates the intellect inherent only to Human Being. [ABSTRACT FROM AUTHOR]

The article talks about the complex system of earth that includes atmosphere, hydrosphere, lithosphere, biosphere, solar terrestrial space and its interaction, evolution between the subsystems of the earth and analyzing sediment source by using paleocurrent direction, paleoclimate and tectonic background. It talks about the ordos basin in China that is located in China craton and the highland denuded zones in the Middle Triassic Ordos Basin.

The regional gas geochemical profile was first performed in the South China Sea in the north–south direction in January 2017 (42nd cruise of the R/V Akademik Boris Petrov). Five zones with methane emission into the atmosphere with a maximum of 30 mole km–2 day–1, were revealed above the oil- and gas-bearing structures in the southern part of the sea, in the Nam Con Son Basin. Methane emission into the atmosphere is generally related to ascending migration of methane from hydrocarbon deposits along fault zones. The expedition was set up by the Council for the Earth's Hydrosphere of the Federal Agency for Scientific Organization as part of the international project "The 2nd International Indian Ocean Expedition (IIOE-2)." [ABSTRACT FROM AUTHOR]

Developing scientific literacy about water systems is critical for K‐12 students. However, even with opportunities to build knowledge about the hydrosphere in elementary classrooms, early learners may struggle to understand the water cycle (Forbes et al., ; Gunckel et al., ; Zangori et al., ; Zangori et al.,). Scientific modeling affords opportunities for students to develop representations, make their ideas visible, and generate model‐based explanations for complex natural systems like the water cycle. This study describes a comprehensive evaluation of a 5‐year, design‐based research project focused on the development, implementation, revision, and testing of an enhanced, model‐centered version of the Full Option Science System (FOSS) Water (2005) unit in third grade classrooms. Here, we build upon our previous work (Forbes et al., a; b; Vo et al., ; Zangori et al., ; Zangori et al.,) by conducting a comparative analysis of student outcomes in two sets of classrooms: (1) one implementing the modeling‐enhanced version of the FOSS Water unit developed by the research team (n = 6), and 2) another using the standard, unmodified version of the same curricular unit (n = 5). Results demonstrate that teachers in both conditions implemented the two versions of the curriculum with relative fidelity. On average, students exposed to the modeling‐enhanced version of the curriculum showed greater gains in their model‐based explanations for the hydrosphere. Engagement in scientific modeling allowed students to articulate hydrologic phenomena by (1) identifying various elements that constitute the hydrosphere, (2) describing how these elements influenced the movement of water in the hydrosphere, and (3) demonstrating underlying processes that govern the movement of water in the hydrosphere. [ABSTRACT FROM AUTHOR]

Short-term forecasts of atmospheric, oceanic, and hydrological effective angular momentum functions (EAM) of Earth rotation excitation are combined with least-squares extrapolation and autoregressive modeling to routinely predict polar motion (PM) and ΔUT1 for up to 90 days into the future. Based on hindcast experiments covering the years 2016 and 2017, a best performing parametrization was elaborated. At forecast horizons of 10 days, remaining prediction errors are 3.02 and 5.39 mas for PM and ΔUT1, respectively, corresponding to improvements of 34.5 and 44.7% when compared to predictions reported routinely in Bulletin A of the International Earth Rotation and Reference Systems Service. At forecast horizons of 60 days, prediction errors are 12.52 and 107.96 mas for PM and ΔUT1, corresponding to improvements of 34.5 and 8.2% over Bulletin A. The 90-day-long EAM forecasts leading to those improved EOP predictions are routinely published on a daily basis at isdc.gfz-potsdam.de/esmdata/eam. [ABSTRACT FROM AUTHOR]

Abstract The deep geological disposal concept is widely accepted by the scientific community for the storage of high activity level nuclear waste. It uses a multi-barrier system to isolate radioactive waste from the hydrosphere and biosphere for hundreds of centuries. The multiple barriers include, from the waste to near- and far-field: metal (e.g., iron or copper) and/or concrete canisters/casks containing the radioactive waste, cement, clay (e.g., smectites) buffer and/or backfill materials, and naturally occurring host rocks (e.g., claystone and granite). The mobility of radionuclides (RNs) is a key issue regarding the safety assessment of nuclear waste repositories, especially for the soluble and mobile RNs, such as 129I, 36Cl, 235, 238U, 79Se, and 99Tc. Among them, 235, 238U, 79Se, 99Mo, and 125Sb are some of the redox-sensitive RNs whose mobility largely depends on their speciation, i.e. , their oxidation states. The interactions of these redox-sensitive RNs with the components of each of the barriers is complex, and it needs to be fully understood for a correct safety assessment. Much progress has been made in the recent years in getting a fundamental understanding of the migration of redox-sensitive RNs in geological media. Here, an overview of the major achievements is presented. In general, the electron donors in repositories can be steel (i.e., zero valent iron), steel reaction products when in contact with groundwater (producing H 2), steel corrosion products (e.g., magnetite, green rust, and ferrous oxyhydroxides), Fe(II)-sulfides (e.g., pyrite, chalcopyrite, and mackinawite), Fe(II)-bearing clays (e.g., Fe-bearing smectites) in claystone, or Fe(II)-bearing mica minerals (e.g., biotite) in granites. All these phases can sorb redox-sensitive RNs and drive reductive immobilization processes. For U and all the redox-sensitive RN oxyanions, the resulting reduced products are the most stable and least soluble phases, such as FeSe 2 for Se or UO 2 for U, which may be favorably formed in the presence of a high solubility of electron donors and fast reaction kinetics. However, with slow reaction kinetics, metastable reduced mixed species in intermediate oxidation states such as Se(0) and hyperstoichiometric uranium oxides are produced. In order to characterize the RN-bearing phases and the uptake and reduction pathway, powerful molecular-scale tools such as X-ray photoelectron spectroscopy (XPS) or X-ray absorption spectroscopy (XAS) are commonly used. Here, we provide a comprehensive perspective on the studies addressing interactions of redox-sensitive RNs with the above-mentioned potential barrier. Highlights • Sorption mechanisms of redox-sensitive RNs on geochemical barriers are reviewed. • Reductive immobilization is an efficient radionuclide removal pathway. • Fe and S bearing minerals act as key reductants in repositories. • Non-redox sorption dominates radionuclide uptake on cement and Fe-free clays. • Minerals with reducing power will create potential reactive interfaces. [ABSTRACT FROM AUTHOR]

The article focuses on helpful tips and instructions for science teachers when it comes to monitoring the hydrosphere. Topics being presented include the importance of teaching students about water and how to manage the human impact on water and aaccessingthe Earth Science Mission Operations website of the U.S. National Aeronautics and Space Administration.

Soil is one of the most complex systems on Earth, functioning at the interface between the lithosphere, biosphere, hydrosphere, and atmosphere and generating a multitude of functions. Moreover, soil constitutes the belowground environment from which plants capture water and nutrients. Despite their great importance, soil properties are often not sufficiently considered in other disciplines, especially in spatial studies of plant distributions. Most soil properties are available as point data and, to be used in spatial analyses, need to be generalised over entire regions (i.e. digital soil mapping). Three categories of statistical approaches can be used for such purpose: geostatistical approaches (GSA), predictive-statistical approaches (PSA), and hybrid approaches (HA) that combine the two previous ones. How then to choose the best approach in a given soil study context? Does it depend on the soil properties to be spatialized, the study area’s characteristics, and/or the availability of soil data? The main aims of this study was to review the use of these three approaches to derive maps of soil properties in relation to the soil parameters, the study area characteristics, and the number of soil samples. We evidenced that the approaches that tend to show the best performance for spatializing soil properties were not necessarily the ones most used in practice. Although PSA was the most widely used, it tended to be outperformed by HA in many cases, but the latter was far less used. However, as the study settings were not always properly described and not all situations were represented in the set of papers analysed, more comparative studies would be needed across a wider range of regions, soil properties, and spatial scales to provide robust conclusions on the best spatialization methods in a specific context. [ABSTRACT FROM AUTHOR]

Abstract: The main aim of this work is to obtain new data on the seasonal variability of the vertical flux of sedimentary matter, its composition, and its transformation during deposition on the seafloor using materials from a year's exposure of sediment traps in the central part of the Black Sea. [ABSTRACT FROM AUTHOR]

Abstract Circulation of hydrothermal fluids within the oceanic crust is a major factor in mass and heat transfer between hydrosphere and lithosphere. Many occurrences of massive sulfide have been reported along the mid-ocean ridges, showing effective mass transfer of sulfur and metals in these systems. Besides precipitation of sulfide at the seafloor, replacive sulfide formation in the sub-seafloor has been documented. However, different lithologies are expected to have different affinities to sulfidization. To investigate the role of rock composition on sulfidization efficiency, we have conducted batch experiments at 250 °C and 400 bars that placed an H 2 S-rich hydrothermal fluid into contact with four different rock types: dunite (olivine separates), troctolite, basalt, and serpentinite. These rocks were exposed to fluids containing 20 mmol/kg total dissolved sulfide for durations between 1 and 10 weeks. In situ fluid sampling allowed us to determine the evolution of the concentrations of ionic solutes and dissolved gases. Solid products were analyzed after termination of the experiments, using XRD, SEM, TG and VSM. Geochemical modeling was employed to compare observed reaction with equilibrium thermodynamic predictions. Sulfide (in the form of euhedral pyrite crystals) could be observed only in the basalt experiment. In all other runs, prevailing H 2 S-activities were too low for sulfide formation despite high total sulfide concentrations. Instead, the troctolite and peridotite experiments showed serpentinization of olivine and magnetite formation. Plagioclase in troctolite experienced desilicification, resulting in andradite formation. The stability field of sulfide in the H 2 -H 2 S activity plane is diminished due to the prevalence of andradite in hydrothermally reacted troctolite and sulfidization in the troctolite experiment was hence inhibited. The serpentinite experiment showed very little reaction and no sulfide formation. Our results show that olivine-rich seafloor lithologies are not very prone to sulfidation; basaltic crust appears to have a larger potential to form sulfide deposits. In some experiments, pyrrhotite did not form although H 2 -H 2 S activities plot in the pyrrhotite stability field of the Fe-O-S phase diagram. We suggest that the higher oxidation state in basalt allows for the precipitation of pyrite, which is not stable under the more reducing conditions prevailing where water interacts with olivine-rich lithologies. Highlights • Basalt showed growth of euhedral pyrite on dissolving minerals. • Olivine was partly serpentinized. • Serpentinite showed no major alteration. • Troctolite was fully serpentinized and plagioclase desilicified. • Sulfur activity is more important to sulfidation than ∑S. [ABSTRACT FROM AUTHOR]

Abstract The radioactive isotope 129I, with a half-life of 1.57 × 107 years, is widely used as a tracer to assess nuclear safety, to track environmental and geological events and to figure out the details of the stable iodine geochemical cycle. This work investigated the 129I and 127I distribution in water samples collected from the terrestrial (rivers, lakes and springs) and marine water systems (estuary and sea) in China. The measured 129I concentrations of (1–51) × 106 atoms/L and 129I/127I ratios of (0.03–21) × 10−10 shows the variability of 129I level in the water systems. The local permafrost and seasonal frozen environment play a key role in groundwater recharge in the Qinghai-Tibet region, which is reflected in the 129I distribution in surface water. The depth distribution of 129I in the water column of the South China Sea reflects the effluence of different currents. The results also indicate that the hydrosphere of China contains one to three orders of magnitude less 129I compared to those reported in Europe. Despite the large distance, the European nuclear fuel reprocessing facilities represent the major source of 129I in the hydrosphere of China through atmospheric transport. The contribution of the Fukushima nuclear accident to 129I levels in the hydrosphere of China was negligible. Highlights • Variable 129I concentrations (1–51) × 106 atoms/L occur in the hydrosphere of China. • The range of 129I/127I is (0.03–21) × 10−10 in the hydrosphere of China. • Depth profiles of 129I in the South China Sea water reveal effects of different ocean currents. • Emissions from the Nuclear fuel reprocessing facilities is the major source of 129I in China. [ABSTRACT FROM AUTHOR]

Trace metal concentration in black shales can hold valuable information regarding ancient deep-ocean redox state. The size of marine reservoir of redoxsensitive elements (particularly molybdenum and chromium) is principally controlled by the extent of anoxicity in marine conditions following the onset of oxidative weathering post Great Oxygenation Event (~2.5-2.3 Ga). Hence, it is considered that coupled analysis involving redox-sensitive element/s and primary organic productivity (total organic carbon) may provide a clue for redox behaviour of ancient deep ocean. Here, we use the redox behaviour of Mo and total organic carbon values of Vindhyan shales to show that the Vindhyan hydrosphere although initiated as a stratified sea with anoxic and sulphidic deep water as exemplified by the geochemical character of the Arangi Shale, the extent and veracity of anoxicity and euxinicity was never pervasive. It further suggests that the Vindhyan hydrosphere developed euxinic deep water only during deposition of Arangi, Rampur and Bijaygarh black shale and was anoxic but certainly not euxinic during Koldaha and Rewa sedimentation. The low concentration of Mo and Cr, in general, in argillaceous intervals suggests that the Vindhyan Sea behaved as a moderate Mo and depleted Cr reservoir. The consistent low concentration of Cr within the Vindhyan shales also suggests restriction in the availability of Cr in the water column in the absence of any significant detrital supply of Cr at very low atmospheric oxygen level (<0.1% PAL; present atmospheric level). [ABSTRACT FROM AUTHOR]

Speleothems, as secondary carbonate deposits, precipitate in the cave environment from the water originally sourced from the ocean, transferred via atmosphere through soil and epikarst into the cave system. As such, they archive valuable information on the ongoing changes in the atmosphere, biosphere, hydrosphere and lithosphere which may be used for palaeoenvironmental reconstructions, especially for the Quaternary Period. Speleothem-based Quaternary research in Croatia started in the 1960's with the utilization of the flowstone and speleothems whose radiometric ages ( 14 C and U-Th) provided constrained chronological framework for underlying fossils or archaeological material, mainly without any further palaeoenvironmental interpretations. Since the 1990's, several studies have used speleothems for the reconstruction of particular phases of speleogenesis, while in the early 2000's investigation on submerged speleothems started, with the aim to reconstruct Quaternary relative sea-level changes along the eastern Adriatic coast. Only after that, thorough research on subaerial speleothems from the different regions of the Croatian karst has been initiated, usually associated with monitoring programs. This paper gathers the most important speleothem-based studies, displaying potential of this still understudied, but promising area in the terms of palaeoclimate and palaeoenvironmental changes in a wider European and global context. [ABSTRACT FROM AUTHOR]

A >1500–km–long northeast–southwest trending Neoproterozoic metamorphic belt in the South China Craton (SCC) consists of subduction mélange and extensional basin deposits. This belt is present under an unconformity of Devonian–Carboniferous sediments. Tectonic evolution of the Neoproterozoic rocks is crucial to determining the geology of the SCC and further influences the reconstruction of the Rodinia supercontinent. A subduction mélange unit enclosed ca.1000–850–Ma mafic blocks, which defined a Neoproterozoic ocean that existed within the SCC, is exposed at the bottom of the Jiangnan Orogen (JO) and experienced at least two phases deformation. Combined with new (detrital) zircon U–Pb ages from metasandstones, as well as igneous rocks within the metamorphic belt, we restrict the strongly deformed subduction mélange as younger than the minimum detrital age ca. 835 Ma and older than the ca. 815 Ma intruded granite. Unconformably overlying the subduction mélange and the intruded granite, an intra–continental rift basin developed <800 Ma that involved abundant mantle inputs, such as mafic dikes. This stratum only experienced one main phase deformation. According to our white mica 40Ar/30Ar data and previously documented thermochronology, both the Neoproterozoic mélange and younger strata were exhumed by a 490–400–Ma crustal–scale positive flower structure. This orogenic event probably induced the thick–skinned structures and was accompanied by crustal thickening, metamorphism and magmatism and led to the closure of the pre–existing rift basin. Integrating previously published data and our new results, we agree that the SCC was located on the periphery of the Rodinia supercontinent from the Neoproterozic until the Ordovician. Furthermore, we prefer that the convergence and dispersal of the SCC were primarily controlled by oceanic subduction forces that occurred within or periphery of the SCC. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) is one of the most important fluxes in terrestrial ecosystems that regulate atmosphere–hydrosphere–biosphere interactions. Several studies have suggested that global ET has significantly increased in the past several decades, and that such increase has exhibited big spatial variability, but there are few detailed studies on the spatio-temporal change in ET over China. Here, we developed a high-resolution data-oriented monthly ET product in China between 1982 and 2015 by integrating remote-sensing and the eddy covariance technique observed ET data in a machine learning approach (model tree ensemble, MTE). We showed that the mean annual ET over China is 552 ± 14 mm yr −1 , which is comparable to the estimate from a MTE-derived product based on water balance, but is larger than that from both previous MTE-derived global product and process-based land surface models. ET in China significantly increased with a rate of 10.7 mm yr −1 per decade over the past 30 years ( p  < 0.05). The largest increases in ET (>60 mm yr −1 per decade) occurred in the eastern periphery of Sichuan, southern Taiwan, and central China, which was attributed to the increases in temperature and solar radiation, as well as the enhanced vegetation productivity. About 22% of the area showed a decreasing trend in ET, mainly in parts of southeastern, southwestern, and northeastern China. The regional decrease in ET was likely due to decreasing precipitation and/or vegetation browning. Although our finding of the significant increase in China’s ET at the country scale is supported by five different ET products, there are still less agreement on the change in ET at the regional scale among different ET products. [ABSTRACT FROM AUTHOR]

The peculiarities of the generation of infragravity sea waves with the periods from 30 s to 5 minutes are identified by the processing and analysis of experimental data obtained with the laser meter of hydrosphere pressure variations in the Vityaz’ Bay (the Sea of Japan). [ABSTRACT FROM AUTHOR]