István Gábor Hatvani

Verified

István verified their affiliation via an institutional email.

Learn more

Verified

István verified their affiliation via an institutional email.

Learn more

• Ph.D.
• Senior research fellow at Research Centre for Astronomy and Earth Sciences

Water protection is one of the most important goals in environmental protection. The Clean Water Act in the USA and the Water Framework Directive (WFD) in Europe are the legal frameworks to facilitate the achievement of this goal. The question is raised of whether more information can be extracted from WFD-related groundwater data. To answer it, a...

The classification of observations into groups is a general procedure in modern research. However, when searching for homogeneous groups the difficulty of deciding whether further division of a classification is necessary or not to obtain the desired homogeneous groups arises. The presented method, Combined cluster and discriminant analysis (CCDA),...

In most of the world along with urbanization came the deterioration of surface waters. The case of Hungary's Lake Balaton (the largest shallow freshwater lake in Central Europe) and its catchment area was no exception. In the second part of the twentieth century it became clear that measures had to be taken to prevent further water quality deterior...

Lake Balaton is the largest shallow freshwater lake in Central Europe. Its water quality is mainly affected by the supplying rivers and other water sources. The primary source is the Zala River. The water of this river used to be filtered by the Kis-Balaton wetland (KBW) before entering Lake Balaton at Keszthely Bay. In the course of the nineteenth...

Study Region: The 3000 km 2 of the Panama Canal Watershed. Study Focus: This study provides insight into the spatiotemporal behavior of precipitation across the PCW 1 utilizing 6-day rainfall records from 29 meteorological stations from 1950 to 2019. The focus interval of 2000-2017 offered the most complete spatiotemporal coverage of the long-term...

The ratio between the heavy and light stable isotopes in precipitation ( δ p ) is an effective tool in answering questions in hydrology, climatology, biogeochemistry and other disciplines, but only if spatiotemporally sufficient data is available provided by precipitation monitoring networks. However, when gathered into large databases this can con...

The SISAL webApp (Hatvani et al., 2024) is a web-based tool designed to query the Speleothem Isotope Synthesis and AnaLysis (SISAL) database (Comas-Bru et al., 2017). This software provides an intuitive front-end interface for exploring the SISAL database, while also offering the accompanying SQL code as a learning resource.

Speleothems are calcium carbonate deposits formed by the degassing of high pCO2 groundwaters typically found in karstic caves. They are a globally distributed geological archive that store information of climate and environmental changes at the time of their formation in multiple proxies, and crucially, provide excellent age control through uranium...

Az előadás célja, hogy bemutassa, felfedezhetőek-e objektíven detektálható és statisztikai szempontból szignifikáns változások Kelet-Közép-Európa egyik leghosszabb homogenizált hőmérsékleti adatsorában. A globális tendenciához hasonlóan a keszthelyi éves középhőmérsékleti idősorban is azonosítható a huszadik század eleji felmelegedés (a továbbiakba...

Can large language models (LLMs) capture a trustworthy global snapshot of the current issues and top-priority questions facing Earth and Geoscience? This article discusses the 100 most important questions facing Earth and Geosciences in the twenty-first century according to the largest of the LLMs. The study uncovered a discrepancy in responses usi...

Monographic processing of Avar Period (6–8th century) glass beads. Approx. 200 glass beads have been selected from 13 archaeological sites in current day Hungary as the representatives of typical Avar glass beads. The beads were analyzed with electron microprobe analyzer attached with wavelength dispersive X-ray spectrometer and/or energy dispersiv...

Groundwater flow systems are influenced by the changes in surface waters as well as climatic factors. These teleconnections significantly increase in cases of extreme weather conditions. To prepare and mitigate the effect of such phenomena, the background factors that create and influence natural processes must be recognized. In the present study,...

Palaeoclimate information on multiple climate variables at different spatiotemporal scales is becoming increasingly important to understand environmental and societal responses to climate change. A lack of high-quality reconstructions of past hydroclimate has recently been identified as a critical research gap. Speleothems, with their precise chron...

Diffuse Reflectance Infrared Fourier Transform Spectroscopy (FTIR DRIFT) is a widely used method for investigating soil organic materials. The existing literature suggests variations in sample preparation techniques for soil analysis. Notably, the powdering and drying method may influence the presence of organic materials, clay minerals, and carbon...

The goal of the present paper is to investigate whether any objectively defined and statistically significant changes can be discovered in one of the longest homogenized instrumental temperature records in East-Central Europe. Thus, it is hoped that the present analysis will add to earlier attempts and elucidate the persistence of the warming perio...

Sheet erosion is a complex multi-factor-dependent process with high spatial heterogeneity on hillslopes. Although the individual factors have been well studied, their aggregated effect on size-selective erosional processes is highly uncertain. Therefore, this study concentrates on the aggregate size distribution and effective particle size distribu...

Paleoclimate information on multiple climate variables at different spatiotemporal scales is increasingly important to understand environmental and societal responses to climate change. A lack of high-quality reconstructions of past hydroclimate has recently been identified as a critical research gap. Speleothems, with their precise chronologies, w...

We present the ‘SISAL webApp’—a web-based tool to query the Speleothem Isotope Synthesis and AnaLysis (SISAL) database. The software provides an easy-to-use front-end interface to mine data from the SISAL database while providing the SQL code alongside as a learning tool. It allows for simple and increasingly complex querying of the SISAL database...

Primordial radionuclides can be found in all environmental compartments. Since coal-fired power plants (CFPP) can be a source of additional radionuclide contamination because coal contains natural radioactive isotopes such as 238U (226Ra) and 232Th. This study investigated the impact of such possible radionuclide contamination from former heavy ind...

A stalagmite was collected in northern Hungary from the Vacska Cave, where monitoring and ventilation-based site selection had been conducted. The stalagmite covers the 10–8 ka (relative to AD 1950) period, including the so-called 8.2 ka event, and showed preceding signs of climate change that were evaluated by petrographic observations, ¹⁴ C activ...

Stable isotopes of hydrogen and oxygen are important natural tracers with a wide variety of environmental applications (e.g., the exploration of the water cycle, ecology and food authenticity). The spatially explicit predictions of their variations are obtained through various interpolation techniques. In the present work, a classical random forest...

Loess-paleosol bluffs can become unstable as a result of urbanization when houses are being built on them because of the panorama. The general effect of water in landslides is well known but still a hot topic. In this study, we explore the connection of landslides to weather conditions, such as the amount of rainfall or water level changes of the R...

Loess-paleosol bluffs can be unstable, but in the course of urbanization, houses may be built in such locations to take advantage of the view. One factor affecting the stability of such bluffs is water, the role of which in mass movements is well established. In this study, the connection of mass movements to meteorological conditions, such as rain...

Lake Velence is a popular tourist destination in Hungary; thus, the lake is the focus of continuous interest and is constantly examined regarding water quality and quantity. In recent years, the lake's water level has shown a severely deteriorating tendency, possibly caused by climate change. Since the lake’s existence is threatened, it has become...

The covariance of stable hydrogen (δ²H) and oxygen (δ¹⁸O) isotopes in local precipitation (the local meteoric water line – LMWL) serves as a benchmark in isotope hydrological or paleoclimatological applications. However, the isotope hydrometeorological monitoring network is still sparse in many parts of the Mediterranean, and the degree of spatial...

Stable isotopes of precipitation are important natural tracers in hydrology, ecology, and forensics. The spatially explicit predictions of oxygen and hydrogen isotopes in precipitation are obtained through different interpolation techniques. In the present study we aim to examine the performance of various interpolation techniques when predicting t...

Stable isotope approaches are widely applied in plant science and many improvements made in the field focus on the analysis of specific components of plant tissues. Although technical developments have been very beneficial, sample collection and preparation are still very time and labor-consuming. The main objective of this study was to create a qu...

his study deals with assessment of potential exposure of natural (238U, 232Th, 40K) and artificial radionuclide (137Cs) around a former coal fired power plant using long-term accumulated attic dust material, (considered as undisturbed) and urban soil (considered as disturbed) from northern part of Hungary in city of Salgótarján. Radionuclide activi...

Primordial radionuclides can be found in all environmental compartments. Coal-fired power plants (CFPP) can be a source of additional contribution because coal contains trace amounts of natural radionuclides such as 40K, 238U, and 232Th and their decay products. These radionuclides can be released as fly ash from power plants and deposited from the...

Due to the Chernobyl nuclear power plant accident, contaminated air masses, containing 137Cs, were widely propagated across all of Europe. Cesium-137 is easily adsorbed on aerosol particles as it returns to the litho�sphere/pedosphere/via wet and dry deposition in the form of a radioactive fallout component. Following the nuclear accident, primar...

Aim: This chapter provides an insight into the diversity of constructed wetlands across large geographic range and their functional role in treating both point and non-point sources of pollutants while simultaneously providing other services such as habitats for biodiversity. Main concepts covered: The four case studies included in this chapter hig...

This chapter gives an overview of the types of (semi-) constructed wetlands, and how these can be applied for the management and, specifically, the retention of agricultural diffuse loads so that they do not reach inland surface waters. To achieve an effective wetland design, a multi-faceted approach is required, which accounts for the location of...

Small streams are crucial but vulnerable elements of ecological networks. To better understand the occurrence of pharmaceutically active compounds (PhACs) in streams, this study focused on the occurrence, distribution, and environmental risk of 111 PhACs and 7 trace elements based on a total of 141 water and sediment samples from small streams loca...

The detection of periodic fluctuations is important in the quest for a deeper understanding of the drivers of past climates in the interests of being better able to understand the climate changes which are likely in the decades to come. Paleoclimatological information derived from natural archives is typically accompanied by chronological uncertain...

Structural changes, or changepoints, coinciding in multiple ice core records over the Greenland Ice Sheet (GrIS) may reflect a widespread response of the GrIS to atmospheric forcing. Thus, to better understand how atmospheric circulation may regulate sudden changes in δ¹⁸O of Greenland precipitation, we seek synchronous changepoints occurring in ic...

The evaluation of shear stress versus shear displacement curves is in the main focus of geotechnical engineering. Such curves, depending on the rock assessed, consist of a quasi-linear section, followed by a "kick" representing the peak shear strength, and a residual part, mostly parallel to the abscissa. The aim of the present study is to facilita...

The modeling of karst water level fluctuations is a crucial task in the water resource management of vulnerable karstic areas. In the Transdanubian Range (East Central Europe, Hungary), from 1950 to 1990, coal and bauxite mining were carried out, with large amounts of karst water being extracted, thus lowering the water table by amounts ranging bet...

Paleoclimate databases are powerful tools for improving climate models. The recent work of speleothem researchers offers lessons on creating a lasting database and fostering the needed mindset.

Shallow groundwater is one of the primary sources of fresh water, providing river base-flow and root-zone soil water between precipitation events. However, with urbanization and the increase in demand for water for irrigation, shallow groundwater bodies are being endangered. In the present study, 101 hydrographs of shallow groundwater monitoring we...

The combined use of the stable isotope compositions of speleothem carbonate and inclusion-hosted water presents great potential in paleotemperature reconstructions, due to the various temperature-dependent isotope fractionations detected in cave systems and their environment. This paper evaluates the applicational possibilities of hydrogen and oxyg...

A detailed knowledge of the stable isotope signature of precipitation is the basis of investigations in a variety of scientific fields and applications. To obtain robust and reliable results, the representativity of the currently operating (at least, as of 2018) precipitation stable isotope monitoring stations across Slovenia (n = 8) and Hungary (n...

Societal concerns about future hydroclimate changes urge a thorough understanding of the governing processes. Here, an analysis of Middle and Late Holocene speleothem-based hydroclimate reconstructions and paleoclimate model simulations reveals sub-millennial fluctuations in the spatiotemporal variability of precipitation in the European and Medite...

Future hydroclimate projections of global climate models for East-Central Europe diverge to a great extent, thus, constrain adaptation strategies. To reach a more comprehensive understanding of this regional spread in model projections, we make use of the CMIP5 multi-model ensemble and six single-model initial condition large ensemble (SMILE) simul...

Data supporting Comas-Bru et al., 2020 (ESSD): https://doi.org/10.5194/essd-12-2579-2020

Characterizing the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, correlating climate events between records, assessing climate periodicities, identifying potential triggers and evaluating climate model simulations. The first global compilation of speleothem isotope records by the SISAL (Speleothem Isoto...

Soil erosion is a complex, destructive process that endangers food security in many parts of the world; thus, its investigation is a key issue. While the measurement of interrill erosion is a necessity, the methods used to carry it out vary greatly, and the comparison of the results is often difficult. The present study aimed to examine the results...

Tritium (3H) as a constituent of the water molecule is an important natural tracer in hydrological sciences. The anthropogenic tritium introduced into the atmosphere unintentionally became an excellent tracer of processes on a time scale of up to 100 years. A prerequisite for tritium applications is to know the distribution of tritium activity in p...

It is generally observed that precipitation is gradually depleted in ¹⁸O and ²H isotopes as elevation increases (‘altitude’ effect) or when moving inland from seacoasts (‘continental’ effect); the regionally accurate estimation of these large-scale effects is important in isotope hydrological or paleoclimatological applications. Nevertheless, seaso...

The over-enrichment of shallow lakes in nutrients has emerged as one of the main causes of water quality deterioration, and is today a major focus of water quality studies worldwide. In the present work, changes in trophic conditions over three decades (1985-2017) in the largest shallow freshwater lake in Central Europe, Lake Balaton, are assessed...

A saját fejlesztésű ImaGeo rendszer terepen, fúrásokban és bányatérségekben is nagy felbontású, digitális földtani dokumentációt és 3D földtani-tektonikai adatfelvételt tesz lehetővé, normál és UV fény megvilágításban egyaránt. A fúrásokban kapott adatok mélyfúrás-geofizikai akusztikus (Borehole televiewer, BHTV) vagy ellenállás (pl. Formation Micr...

Shallow groundwater acts as an important source of water for the ecosystem, agriculture, drinking water supply, etc.; it is, however, among those water resources most sensitive to climate change, and especially to aridification. In the present study, the delineation of regional recharge and discharge zones of the Danube–Tisza Interfluve (Hungary, 8...

Abstract. Characterising the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, for correlating climate events between records, for assessing climate periodicities, identifying potential triggers, and to evaluate climate model simulations. The first global compilation of speleothem isotope records by the SIS...

Additional methodological description and predicted amount-weighted isoscapes (1×1 km grid) of d18O and d2H for Iberian precipitation are provided in GEOtiff format.

Abstract. Tritium (³H) as a constituent of the water molecule is an important natural tracer in hydrological sciences. The anthropogenic tritium introduced into the atmosphere became unintentionally an excellent tracer of processes on the time scale of up to a 100 years. A prerequisite for tritium applications is to know the distribution...

The isotopic composition of precipitation provides insight into the origin of water vapor, and the conditions attained during condensation and precipitation. Thus, the spatial variation of oxygen and hydrogen stable isotope composition (δp) and d-excess of precipitation was explored across the Iberian Peninsula for October 2002–September 2003 with...

Stable isotope composition of biological materials records the prevailing e.g. climatological, hydrological conditions; thus, serves as important biogeochemical marker in determining the authenticity of agricultural products and in tracing their origins. The application of isotopes of the water molecule in research activities is steadily increasing...

Zusammenfassung Die vorliegende Arbeit gibt einen Überblick über die Untersuchungen zur mikrobiologisch-hygienischen Wasserqualität des Neusiedler Sees. Am Beginn steht ein historischer Abriss über die Entwicklung eines entsprechenden Monitorings. Es folgt eine statistische Analyse mikrobiologischer Langzeitdaten (1992 bis 2013) und deren Verknüpfu...

The region comprising of East Central Europe, South East Europe and Turkey contributed to the SISAL (Speleothem Isotopes Synthesis and AnaLysis) global database with stable carbon and oxygen isotope time-series from 18 speleothems from 14 caves. The currently available oldest record from the studied region is the ABA-2 flowstone record (Abaliget Ca...

Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercom...

Dissolved oxygen is one of the most important water quality parameters in relation to aquatic life, and one of the most direct indicators of water pollution. The present study employs a novel methodology for the estimation of riverine dissolved oxygen using neural network models taking the spatial homogeneity of the water quality sampling sites int...

Planktic algae have an essential role in the food web as primary producers; the determination of the ecological niche space occupied by them is thus essential in strategies aimed at sustaining the biodiversity of surface waters. In the present study, principal component analysis combined with the outlying mean index was applied to 14 water quality...

A stalagmitic flowstone deposit from the Béke Cave (called Nagy-tufa deposit), East-Central Europe is characterized by complex, climate related textural and geochemical records as documented from a drill core (BNT-2 core) covering the period of 4 to 1 ka cal BP. The core location was monitored in an earlier study. Based on monitoring, textural and...

The aim of the present study is to extend the applicability of MRI measurements similar to those used in human diagnostics to the examination of water barriers in living plants, thus broadening their use in natural sciences. The cucumber, Cucumis sativus, and Phillyrea angustifolia, or false olive, were chosen as test plants. The MRI measurements w...

To minimize the risk of negative consequences for public health from fecal pollution in lakes, the continuous surveillance of microbiological water quality parameters, alongside other environmental variables, is necessary at defined bathing sites. Such routine surveillance may prove insufficient to elucidate the main drivers of fecal pollution in a...

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-sample” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Sy...

Anthropogenic activity such as damming or diversion of rivers cause extensive disturbance to ecosystems, as well as the interaction between surface water and groundwater. Following the diversion in 1992 of the River Danube (NW Hungary) and the construction of a water barrage system, the level of shallow groundwater dropped and altered the connectio...

The efficient operation of shallow groundwater (SGW) monitoring networks is crucial to water supply, in-land water protection, agriculture and nature conservation. In the present study, the spatial representativity of such a monitoring network in an area that has been thoroughly impacted by anthropogenic activity (river diversion/damming) is assess...

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-sample” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Sy...

The application of stable and radioactive isotopes of the water molecule in various research activities is steadily increasing worldwide. Precipitation isotope mapping has revolutionized during last decades and isoscapes were calculated based on data from Global Network of Isotopes in Precipitation (GNIP) database and different regional databases....