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1

Wyman, Teresa M. "Prediction of Seismic and Volcanic Activity". Science & Technology Libraries 8, n. 3 (29 novembre 1988): 55–83. http://dx.doi.org/10.1300/j122v08n03_08.

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Iguchi, Masato, Surono, Takeshi Nishimura, Muhamad Hendrasto, Umar Rosadi, Takahiro Ohkura, Hetty Triastuty et al. "Methods for Eruption Prediction and Hazard Evaluation at Indonesian Volcanoes". Journal of Disaster Research 7, n. 1 (1 gennaio 2012): 26–36. http://dx.doi.org/10.20965/jdr.2012.p0026.

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We report methods, based on geophysical observations and geological surveys, for the prediction of eruptions and the evaluation of the activity of 4 volcanoes in Indonesia. These are Semeru, Guntur, Kelud and Sinabung volcanoes. Minor increases in tilt were detected by borehole tiltmeters prior to eruptions at the Semeru volcano depending on the seismic amplitude of explosion earthquakes. The results show the possibility of prediction of the type and magnitude of eruption and the effectiveness of observation with a high signalto-noise ratio. The establishment of background data is important for evaluating volcanic activity in longterm prediction. Typical distributions of volcanic and local tectonic earthquakes were obtained around the Guntur volcano, where geodetic monitoring by continuous GPS observation is valuable. The cumulative volume of eruptive products is valuable for evaluating the potential for future eruption. The eruptive rate of the Kelud volcano is ca 2×106m3/y (dense rock equivalent), but the volume of the 2007 eruption was only 2×107m3, suggesting a still high potential for eruption. Based on geological surveys and dating, an eruption scenario is proposed for the activity of Mt. Sinabung, where phreatic eruptions occurred in 2010 after a historically long dormancy.
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Rummel, Lisa, Alexander Bartels e Franz May. "Using a multi-criteria approach for a regional differentiation of the likelihood of future volcanic activity in Germany". Safety of Nuclear Waste Disposal 2 (6 settembre 2023): 143. http://dx.doi.org/10.5194/sand-2-143-2023.

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Abstract. Future volcanic activity, which might influence the long-term stability of radioactive waste repositories, must be evaluated critically. In Germany, according to the Repository Site Selection Act (StandAG), areas in which Quaternary volcanism is either present or future volcanic activity is expected within the next 1 Ma must be excluded from the site selection process for a high-level radioactive waste repository. However, while regions with Quaternary volcanism are reasonably well known in Germany, forecasting volcanic activity in intraplate fields is difficult, as many processes and their interaction control the spatial distribution of the volcanic centres. To develop an appropriate method to forecast possible regions of volcanic activity, a semi-quantitative, multi-criteria approach is used that combines a variety of indicators including, amongst others, seismic anomalies in the mantle, gravity data, tectonic activity, sutures, ground motion, earthquakes, mantle degassing centres and the geochronological data of volcanic rocks. The used indicators provide possible information about the source of melting in the mantle, the ascent of melt through the lithosphere and the eruption process at the surface. In total, 30 indicators were defined and ranked according to their presumed relevance for the long-term prediction of volcanism, following the results of two expert surveys. Quantifiable parameters were selected for the individual indicators, and threshold values were assigned and related to levels of significance. The parameters were uniformly applied for Germany in order to enable a transparent and equal risk assessment of future volcanic activity in all of the federal states. To consider the uncertainties regarding the distribution and manifestation of parameters in addition to their mostly unknown underlying large-scale processes, buffer zones were defined in which the values of relevance decrease with increasing distance from the initial parameter extent. By combining all parameters into an overall index, the presented results allow the regional differentiation of the likelihood of future volcanic eruptions in Germany. The robustness of the results is shown by varying the weights of the used parameters in the Germany-wide risk map. Different categories for the probability of future volcanic activity can be defined and used, depending on the needs and assessment of the volcanic hazard potential.
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Shiogama, Hideo, Seita Emori, Takashi Mochizuki, Sayaka Yasunaka, Tokuta Yokohata, Masayoshi Ishii, Toru Nozawa e Masahide Kimoto. "Possible Influence of Volcanic Activity on the Decadal Potential Predictability of the Natural Variability in Near-Term Climate Predictions". Advances in Meteorology 2010 (2010): 1–7. http://dx.doi.org/10.1155/2010/657318.

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Initialization based on data assimilations using historical observations possibly improves near-term climate predictions. Significant volcanic activity in the future is unpredictable and not assumed in future climate predictions. To examine the possible influence of unpredictable future volcanic activity on the decadal potential predictability of the natural variability, we performed a 2006–2035 climate prediction experiment with the assumption that the 1991 Mt. Pinatubo eruption would take place again in 2010. The Pinatubo forcing induced not only significant cooling responses but also considerable noises in the natural variability. The errors due to the Pinatubo forcing grew faster than that arising from imperfect knowledge of the observed state, leading to a rapid reduction of the decadal potential predictability of the natural variability.
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5

Scharrer, K., R. Malservisi, Ch Mayer, O. Spieler e U. Münzer. "Combination of SAR remote sensing and GIS for monitoring subglacial volcanic activity – recent results from Vatnajökull ice cap (Iceland)". Natural Hazards and Earth System Sciences 7, n. 6 (27 novembre 2007): 717–22. http://dx.doi.org/10.5194/nhess-7-717-2007.

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Abstract. This paper presents latest results from the combined use of SAR (Synthetic Aperture Radar) remote sensing and GIS providing detailed insights into recent volcanic activity under Vatnajökull ice cap (Iceland). Glaciers atop active volcanoes pose a constant potential danger to adjacent inhabited regions and infrastructure. Besides the usual volcanic hazards (lava flows, pyroclastic clouds, tephra falls, etc.), the volcano-ice interaction leads to enormous meltwater torrents (icelandic: jökulhlaup), devastating large areas in the surroundings of the affected glacier. The presented monitoring strategy addresses the three crucial questions: When will an eruption occur, where is the eruption site and which area is endangered by the accompanying jökulhlaup. Therefore, sufficient early-warning and hazard zonation for future subglacial volcanic eruptions becomes possible, as demonstrated for the Bardárbunga volcano under the northern parts of Vatnajökull. Seismic activity revealed unrest at the northern flanks of Bardárbunga caldera at the end of September 2006. The exact location of the corresponding active vent and therefore a potentially eruptive area could be detected by continuous ENVISAT-ASAR monitoring. With this knowledge a precise prediction of peri-glacial regions prone to a devastating outburst flood accompanying a possible future eruption is possible.
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6

German, Josephine D., Anak Agung Ngurah Perwira Redi, Ardvin Kester S. Ong, Yogi Tri Prasetyo e Vince Louis M. Sumera. "Predicting Factors Affecting Preparedness of Volcanic Eruption for a Sustainable Community: A Case Study in the Philippines". Sustainability 14, n. 18 (9 settembre 2022): 11329. http://dx.doi.org/10.3390/su141811329.

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Volcanic eruption activity across the world has been increasing. The recent eruption of Taal volcano and Mt. Bulusan in the Philippines affected several people due to the lack of resources, awareness, and preparedness activities. Volcanic eruption disrupts the sustainability of a community. This study assessed people’s preparedness for volcanic eruption using a machine learning ensemble. With the high accuracy of prediction from the ensemble of random forest classifier (93%) and ANN (98.86%), it was deduced that media, as a latent variable, presented as the most significant factor affecting preparedness for volcanic eruption. This was evident as the community was urged to find related information about volcanic eruption warnings from media sources. Perceived severity and vulnerability led to very high preparedness, followed by the intention to evacuate. In addition, proximity, subjective norm, and hazard knowledge for volcanic eruption significantly affected people’s preparedness. Control over individual behavior and positive attitude led to a significant effect on preparedness. It could be posited that the government’s effective mitigation and action plan would be adhered to by the people when disasters, such as volcanic eruptions, persist. With the threat of climate change, there is a need to reevaluate behavior and mitigation plans. The findings provide evidence of the community’s resilience and adoption of mitigation and preparedness for a sustainable community. The methodology provided evidence for application in assessing human behavior and prediction of factors affecting preparedness for natural disasters. Finally, the results and findings of this study could be applied and extended to other related natural disasters worldwide.
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7

Dryukova, E. D., G. M. Nerobelov, M. S. Sedeeva, A. V. Kiselev, A. G. Mahura e V. I. Gorny. "Integration of Satellite Monitoring and Mathematical Modeling in the Analysis of the Nature of Elevated Sulfur Dioxide Concentrations in the Surface Air of the Northern Part of Finland". Известия Российской академии наук. Физика атмосферы и океана 59, n. 4 (1 luglio 2023): 450–60. http://dx.doi.org/10.31857/s0002351523040041.

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The article is devoted to the investigation of the nature of the increment in surface concentration of toxic gas sulfur dioxide (SO2) in Northern Finland. The study is carried out for June 2011 when the increased near-surface SO2 concentration was registered at Finnish observation station Inari Raja-Jooseppi together with the surface wind blowing from the territory of the Kola Peninsula. The hypothesis of natural increment of near-surface SO2 concentration as a result of Grímsvötn volcano eruption (Iceland) is verified using satellite SO2 observations by OMI, numerical weather prediction and atmospheric chemistry model Enviro-HIRLAM and particle dispersion model HYSPLIT. The results show that not only local man-made sources, but also the remote transfer of pollutants from volcanic eruptions can cause an increased near-surface SO2 concentration. To verify this hypothesis, a large set of statistics is required in Northern Finland during periods of volcanic activity in Iceland.
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8

Senyukov, S. L. "Monitoring and prediction of volcanic activity in Kamchatka from seismological data: 2000–2010". Journal of Volcanology and Seismology 7, n. 1 (febbraio 2013): 86–97. http://dx.doi.org/10.1134/s0742046313010077.

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9

Guemas, Virginie, Susanna Corti, J. García-Serrano, F. J. Doblas-Reyes, Magdalena Balmaseda e Linus Magnusson. "The Indian Ocean: The Region of Highest Skill Worldwide in Decadal Climate Prediction*". Journal of Climate 26, n. 3 (1 febbraio 2013): 726–39. http://dx.doi.org/10.1175/jcli-d-12-00049.1.

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Abstract The Indian Ocean stands out as the region where the state-of-the-art decadal climate predictions of sea surface temperature (SST) perform the best worldwide for forecast times ranging from the second to the ninth year, according to correlation and root-mean-square error (RMSE) scores. This paper investigates the reasons for this high skill by assessing the contributions from the initial conditions, greenhouse gases, solar activity, and volcanic aerosols. The comparison between the SST correlation skill in uninitialized historical simulations and hindcasts initialized from estimates of the observed climate state shows that the high Indian Ocean skill is largely explained by the varying radiative forcings, the latter finding being supported by a set of additional sensitivity experiments. The long-term warming trend is the primary contributor to the high skill, though not the only one. Volcanic aerosols bring additional skill in this region as shown by the comparison between initialized hindcasts taking into account or not the effect of volcanic stratospheric aerosols and by the drop in skill when filtering out their effect in hindcasts that take them into account. Indeed, the Indian Ocean is shown to be the region where the ratio of the internally generated over the externally forced variability is the lowest, where the amplitude of the internal variability has been estimated by removing the effect of long-term warming trend and volcanic aerosols by a multiple least squares linear regression on observed SSTs.
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10

Lombardo, Valerio, Stefano Corradini, Massimo Musacchio, Malvina Silvestri e Jacopo Taddeucci. "Eruptive Styles Recognition Using High Temporal Resolution Geostationary Infrared Satellite Data". Remote Sensing 11, n. 6 (19 marzo 2019): 669. http://dx.doi.org/10.3390/rs11060669.

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The high temporal resolution of the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) instrument aboard Meteosat Second Generation (MSG) provides the opportunity to investigate eruptive processes and discriminate different styles of volcanic activity. To this goal, a new detection method based on the wavelet transform of SEVIRI infrared data is proposed. A statistical analysis is performed on wavelet smoothed data derived from SEVIRI Mid-Infrared( MIR) radiances collected from 2011 to 2017 on Mt Etna (Italy) volcano. Time-series analysis of the kurtosis of the radiance distribution allows for reliable hot-spot detection and precise timing of the start and end of eruptive events. Combined kurtosis and gradient trends allow for discrimination of the different activity styles of the volcano, from effusive lava flow, through Strombolian explosions, to paroxysmal fountaining. The same data also allow for the prediction, at the onset of an eruption, of what will be its dominant eruptive style at later stages. The results obtained have been validated against ground-based and literature data.
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11

Kuswandarto, Hery, Muhamad Hendrasto e Masato Iguchi. "Automatic and Real-time Processing of Tilt Records for Prediction of Explosions at Semeru Volcano, East Java, Indonesia". Indonesian Journal of Physics 19, n. 3 (3 novembre 2016): 69–74. http://dx.doi.org/10.5614/itb.ijp.2008.19.3.2.

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Eruptive activity of Semeru Volcano, East Java, Indonesia, is characterized by intermittent occurrence of strombolian and vulcanian types in intervals of 15 – 45 minutes. The explosive eruptions accompany explosion earthquakes and tilt changes of ground around the summit crater. Prior to the explosions (16 – 300 s before), gradual upward tilts of the crater side were detected with amounts of 0.3 – 20 nrad. The upward tilts turned to downward after start of explosive eruptions and tilt decreased by 0.7 – 50 nrad for 30 – 70 s. In order to detect the precursory tilt changes in real time automatically by using the tilt record, software coded by Visual Basic was developed. The software receives UDP packet data from A/D converter for the tiltmeter and shows the record on PC display. The software judge stages of volcanic activity (pre-eruption or eruption) based on the tilt change. In a test, 72% of increase in tilts prior to explosions was successfully detected.
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12

Hirose, Takashi, Hideki Ueda e Eisuke Fujita. "Identifying Anomalies in Seismic Velocity and Scattering Property Changes at Active Volcanoes Based on Seismic Interferometry and the Local Outlier Probability Method". Journal of Disaster Research 17, n. 5 (1 agosto 2022): 587–99. http://dx.doi.org/10.20965/jdr.2022.p0587.

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The identification of anomalies in seismic wave interferometry data is important in the prediction of imminent volcanic eruptions. Herein, we propose using the local outlier probability (LoOP) method to evaluate the degree of anomaly in seismic wave velocities and scattering properties, estimated via seismic wave interferometry. LoOP is the likelihood that an observation is anomalous and is always in the range of 0–1 (0–100%). We quantitatively evaluated the degree of anomaly in seismic wave velocities and scattering properties before and after the eruption of Mt. Aso, Japan, in October 2016 and Mt. Shinmoedake, which lies within the Mt. Kirishima cluster of volcanoes, Japan, in 2017 and 2018. We found that LoOP exceeded 70% 2 to 3 days before Mt. Aso erupted on October 8, 2016, and it exceeded 70% 1 to 5 days before Mt. Shinmoedake erupted on October 11, 2017 and March 6, 2018. Adjusting the reference and quiet periods for the estimation of changes in seismic velocity/scattering property and LoOP calculations can allow the tracking of repeated, significant LoOP increases during times of high volcanic activity. The quantitative evaluation of temporal anomalies in seismic datasets will improve the precision of predictions of imminent volcanic eruptions.
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Wrobel-Daveau, Jean-Christophe, e Graeme R. Nicoll. "PLATE TECTONICS AS A TOOL FOR GLOBAL SCREENING OF MAGMATIC ARCS AND PREDICTIONS FOR RELATED PORPHYRY DEPOSITS". Economic Geology 117, n. 6 (1 settembre 2022): 1429–43. http://dx.doi.org/10.5382/econgeo.4944.

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Abstract The formation of most mineral deposits is closely linked to a geodynamic context—for example, the association of porphyry Cu-Au-Mo deposits with subduction and development of volcanic arcs. This paper proposes a new approach to the global screening of volcanic arcs and their duration, as a predictive method for a mineral systems-based approach (e.g., discovery of potential porphyry occurrences). The method utilizes geospatial and temporal analytics run on a combination of large global data sets and a global plate tectonic model (covering the time period 600 Ma to present) containing plate boundaries. The method involves (1) calculating present-day arc volcano-to-trench distances and obtaining average volcanic-arc widths in both continental and intraoceanic settings, (2) applying these values to the paleotrenches contained in the plate tectonic model on 53 time intervals spread throughout the Phanerozoic, (3) unreconstructing the results back to present day, and (4) summing up all magmatic arc occurrences using their cumulative durations. This results in a spatiotemporal model of the total cumulative duration of magmatic arc activity at the global scale, back to 600 Ma, that is updatable and can serve as a proxy to predict porphyry deposit likelihood. The model output is tested against a porphyry copper occurrence data set to validate the approach as a predictive proxy for arc-related porphyry deposits. The alignment of the model results with data control is high for most geologic time periods throughout the Phanerozoic—up to 90% in the case of buffered (1σ) magmatic arcs and up to 100% in the case of buffered magmatic arcs with an additional search distance (2σ). Recent advances in plate tectonic model quality and detail now offer a higher level of precision and confidence than ever before and enable tools for the prediction and screening of porphyry deposit locations, as well as opening the potential to screen for other geodynamic context-dependent commodities (e.g., orogenic gold, volcanogenic massive sulfide, or Ni and platinum group element-sulfide deposits), particularly in the search for poorly exposed or subsurface orebodies.
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Asami, Mitsufumi, e Chiori Takahashi. "Drift prediction of pyroclasts released through the volcanic activity of Fukutoku-Okanoba into the marine environment". Marine Pollution Bulletin 186 (gennaio 2023): 114402. http://dx.doi.org/10.1016/j.marpolbul.2022.114402.

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Alqahtani, Faisal, Muhsan Ehsan, Murad Abdulfarraj, Essam Aboud, Zohaib Naseer, Nabil N. El-Masry e Mohamed F. Abdelwahed. "Machine Learning Techniques in Predicting Bottom Hole Temperature and Remote Sensing for Assessment of Geothermal Potential in the Kingdom of Saudi Arabia". Sustainability 15, n. 17 (22 agosto 2023): 12718. http://dx.doi.org/10.3390/su151712718.

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The global demand for energy is increasing rapidly due to population growth, urbanization, and industrialization, as well as to meet the desire for a higher standard of living. However, environmental concerns, such as air pollution from fossil fuels, are becoming limiting factors for energy sources. Therefore, the appropriate and sustainable solution is to transition towards renewable energy sources to meet global energy demands by using environmentally friendly sources, such as geothermal. The Harrat Rahat volcanic field, located in the western region of the Kingdom of Saudi Arabia (KSA), gets more attention due to its geothermal potential as a viable site for geothermal energy exploration due to its high enthalpy. The prime objective of this study is to present up-to-date and comprehensive information on the utilization of borehole temperature and remote sensing data to identify the most prospective zones with significant geothermal activity favorable for exploration and drilling. A brief description of the selected wells and the methodology used to determine the petrophysical parameters relevant to the geothermal potential assessment are presented. Special emphasis is given to gamma-ray ray and temperature logs for calculating heat production and the geothermal gradient. The effectiveness of various machine learning techniques are assessed throughout this study for predicting the temperature-at-depth to evaluate the suitability of employing machine learning models for temperature prediction, and it is found that XG Boost provided excellent results. It can be observed that some linear anomalies can be traced in the NW, trending on the west side of the Harrat volcanic field based on magnetic data interpretation. The land surface temperature in 2021 exhibited higher temperatures compared to 2000, suggesting potential volcanic activity in the subsurface. It is concluded that the integration of remote sensing data with subsurface data provides the most reliable results.
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16

Self, S. "The effects and consequences of very large explosive volcanic eruptions". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, n. 1845 (28 giugno 2006): 2073–97. http://dx.doi.org/10.1098/rsta.2006.1814.

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Every now and again Earth experiences tremendous explosive volcanic eruptions, considerably bigger than the largest witnessed in historic times. Those yielding more than 450 km 3 of magma have been called super-eruptions. The record of such eruptions is incomplete; the most recent known example occurred 26 000 years ago. It is more likely that the Earth will next experience a super-eruption than an impact from a large meteorite greater than 1 km in diameter. Depending on where the volcano is located, the effects will be felt globally or at least by a whole hemisphere. Large areas will be devastated by pyroclastic flow deposits, and the more widely dispersed ash falls will be laid down over continent-sized areas. The most widespread effects will be derived from volcanic gases, sulphur gases being particularly important. This gas is converted into sulphuric acid aerosols in the stratosphere and layers of aerosol can cover the global atmosphere within a few weeks to months. These remain for several years and affect atmospheric circulation causing surface temperature to fall in many regions. Effects include temporary reductions in light levels and severe and unseasonable weather (including cool summers and colder-than-normal winters). Some aspects of the understanding and prediction of super-eruptions are problematic because they are well outside modern experience. Our global society is now very different to that affected by past, modest-sized volcanic activity and is highly vulnerable to catastrophic damage of infrastructure by natural disasters. Major disruption of services that society depends upon can be expected for periods of months to, perhaps, years after the next very large explosive eruption and the cost to global financial markets will be high and sustained.
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Mochizuki, Takashi, Masayoshi Ishii, Masahide Kimoto, Yoshimitsu Chikamoto, Masahiro Watanabe, Toru Nozawa, Takashi T. Sakamoto et al. "Pacific decadal oscillation hindcasts relevant to near-term climate prediction". Proceedings of the National Academy of Sciences 107, n. 5 (11 gennaio 2010): 1833–37. http://dx.doi.org/10.1073/pnas.0906531107.

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Decadal-scale climate variations over the Pacific Ocean and its surroundings are strongly related to the so-called Pacific decadal oscillation (PDO) which is coherent with wintertime climate over North America and Asian monsoon, and have important impacts on marine ecosystems and fisheries. In a near-term climate prediction covering the period up to 2030, we require knowledge of the future state of internal variations in the climate system such as the PDO as well as the global warming signal. We perform sets of ensemble hindcast and forecast experiments using a coupled atmosphere-ocean climate model to examine the predictability of internal variations on decadal timescales, in addition to the response to external forcing due to changes in concentrations of greenhouse gases and aerosols, volcanic activity, and solar cycle variations. Our results highlight that an initialization of the upper-ocean state using historical observations is effective for successful hindcasts of the PDO and has a great impact on future predictions. Ensemble hindcasts for the 20th century demonstrate a predictive skill in the upper-ocean temperature over almost a decade, particularly around the Kuroshio-Oyashio extension (KOE) and subtropical oceanic frontal regions where the PDO signals are observed strongest. A negative tendency of the predicted PDO phase in the coming decade will enhance the rising trend in surface air-temperature (SAT) over east Asia and over the KOE region, and suppress it along the west coasts of North and South America and over the equatorial Pacific. This suppression will contribute to a slowing down of the global-mean SAT rise.
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Cigna, Francesca, Deodato Tapete e Zhong Lu. "Remote Sensing of Volcanic Processes and Risk". Remote Sensing 12, n. 16 (10 agosto 2020): 2567. http://dx.doi.org/10.3390/rs12162567.

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Remote sensing data and methods are increasingly being embedded into assessments of volcanic processes and risk. This happens thanks to their capability to provide a spectrum of observation and measurement opportunities to accurately sense the dynamics, magnitude, frequency, and impacts of volcanic activity in the ultraviolet (UV), visible (VIS), infrared (IR), and microwave domains. Launched in mid-2018, the Special Issue “Remote Sensing of Volcanic Processes and Risk” of Remote Sensing gathers 19 research papers on the use of satellite, aerial, and ground-based remote sensing to detect thermal features and anomalies, investigate lava and pyroclastic flows, predict the flow path of lahars, measure gas emissions and plumes, and estimate ground deformation. The strong multi-disciplinary character of the approaches employed for volcano monitoring and the combination of a variety of sensor types, platforms, and methods that come out from the papers testify the current scientific and technology trends toward multi-data and multi-sensor monitoring solutions. The research advances presented in the published papers are achieved thanks to a wealth of data including but not limited to the following: thermal IR from satellite missions (e.g., MODIS, VIIRS, AVHRR, Landsat-8, Sentinel-2, ASTER, TET-1) and ground-based stations (e.g., FLIR cameras); digital elevation/surface models from airborne sensors (e.g., Light Detection And Ranging (LiDAR), or 3D laser scans) and satellite imagery (e.g., tri-stereo Pléiades, SPOT-6/7, PlanetScope); airborne hyperspectral surveys; geophysics (e.g., ground-penetrating radar, electromagnetic induction, magnetic survey); ground-based acoustic infrasound; ground-based scanning UV spectrometers; and ground-based and satellite Synthetic Aperture Radar (SAR) imaging (e.g., TerraSAR-X, Sentinel-1, Radarsat-2). Data processing approaches and methods include change detection, offset tracking, Interferometric SAR (InSAR), photogrammetry, hotspots and anomalies detection, neural networks, numerical modeling, inversion modeling, wavelet transforms, and image segmentation. Some authors also share codes for automated data analysis and demonstrate methods for post-processing standard products that are made available for end users, and which are expected to stimulate the research community to exploit them in other volcanological application contexts. The geographic breath is global, with case studies in Chile, Peru, Ecuador, Guatemala, Mexico, Hawai’i, Alaska, Kamchatka, Japan, Indonesia, Vanuatu, Réunion Island, Ethiopia, Canary Islands, Greece, Italy, and Iceland. The added value of the published research lies on the demonstration of the benefits that these remote sensing technologies have brought to knowledge of volcanoes that pose risk to local communities; back-analysis and critical revision of recent volcanic eruptions and unrest periods; and improvement of modeling and prediction methods. Therefore, this Special Issue provides not only a collection of forefront research in remote sensing applied to volcanology, but also a selection of case studies proving the societal impact that this scientific discipline can potentially generate on volcanic hazard and risk management.
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Buszta, Julia, Katarzyna Wójcik, Celso Augusto Guimarães Santos, Krystian Kozioł e Kamil Maciuk. "Historical Analysis and Prediction of the Magnitude and Scale of Natural Disasters Globally". Resources 12, n. 9 (5 settembre 2023): 106. http://dx.doi.org/10.3390/resources12090106.

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The aim of this study was to conduct a geospatial analysis of natural disasters occurring worldwide between 1960 and 2018. A total of 9962 disasters were considered, covering 39,953 locations. These phenomena were analysed in terms of frequency and number to determine changes over time and predict future trends. The data included information such as location and year of occurrence. The following natural disasters were included in the analyses: droughts, earthquakes, extreme temperatures, floods, landslides, earth mass movements, storms, and volcanic activity. The analyses were carried out across three dimensions: by continent, by number of disasters in relation to population, and in relation to the area of the continents concerned. An additional objective was to visualise the distribution of disasters by affected countries. This aspect shows the incidence of disasters by year during the period under study, with a 20-year forecast for the coming years.
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Takahashi, Makoto, e Naoyuki Kato. "Special Issue on Literacy for Disaster Resilience: Building a Societal Capacity for Reducing Disasters Due to Earthquake and Volcanic Eruption". Journal of Disaster Research 19, n. 1 (1 febbraio 2024): 17–18. http://dx.doi.org/10.20965/jdr.2024.p0017.

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The national earthquake and national volcanic eruption prediction programs of Japan started in 1965 and 1974, respectively, based on the recommendation of the Geodesy Council. As a result, observations of seismic and volcanic activity have been enhanced and our understanding of the mechanisms of earthquakes and volcanic eruptions has made significant advances. However, these research results did not fully contribute to mitigating the damage caused by the 1995 Kobe earthquake or the 2011 Tohoku earthquake. In order to make further contributions to disaster mitigation, we recognize the importance of research to apply the scientific understanding of earthquakes and volcanic eruptions in collaboration with researchers in related research fields. The Earthquake and Volcano Hazards Observation and Research Program (2014–2018) was thus started on the basis of a recommendation of the Council for Science and Technology. In this Program, research in the area of forecasting the hazards of earthquakes and volcanic eruptions has become one of the main pillars of research. Disaster information and knowledge of the disaster process, which involve the interaction of hazards and natural and social vulnerability, have been investigated in cooperation with earth scientists, engineers, and social scientists. On the basis of our results, research on literacy for disaster resilience was selected as one of the main pillars of research in the Second Observation and Research Program of Earthquake and Volcano Hazards (2019–2023), because a better understanding of and immediate information about disasters are important for disaster mitigation. This special issue, which aims to disseminate the results of almost five years of research activities on literacy for disaster resilience in that Program, includes 15 papers and survey reports from multidisciplinary fields of study. The collection begins with Kimura and Ikeda’s important paper discussing the conceptual structure of the knowledge and abilities necessary to build disaster resilience capacities by analyzing school and community-based efforts, followed by a variety of empirical studies that are loosely categorized into two groups. The first group of papers concerns the understanding of disaster processes and mechanisms themselves as a factor inducing disaster prevention and mitigation. First, Ebina and Sugawara, and Sugimori attempt to learn lessons from the pre-modern earthquake disasters based on past picture maps and scrolled records, respectively, followed by Ohkura’s interesting paper that points to problems in the Aso Volcano disaster mitigation system by analyzing the 2021 phreatic eruption process. Next, utilizing information and communication technology to support effective evacuation, Inoguchi, and Shiozaki and Hashimoto develop a disaster management toolkit and the tsunami drill program, respectively. The following two papers of Takubo et al. discuss behavioral mechanisms in a disaster period based on their simulation experiments from a cognitive science perspective. The second group investigates methods of enhancing people’s literacy for disaster resilience, paying special attention to the interaction between science and civil society, led by Sawada and Sato, and Muroi, both discussing the disaster risk reduction efforts of small and medium-sized enterprises and of community-based organizations, respectively, in anticipation of the Nankai Trough earthquake and tsunami. Next, Kimura and Aikawa propose an education program to enhance the disaster awareness of high school students who have never experienced disasters. Further, four papers deal with the issue of people’s access to scientific knowledge focusing on the roles of university institutes, including case studies of so-called open science initiatives, by Yamori, Nakamichi, and Sakamoto and Nakamichi, and finally, a comparative study of several research centers in volcanic localities by Horii et al. These studies argue for the importance of the concept of literacy for disaster resilience to embed scientific knowledge in society and interconnect theory and practice, but the study of such a concept, especially in relation to earthquakes and volcanic eruptions, has just begun. We hope that this issue will encourage discussions from a wide range of scientists, experts in education and disaster management, and policy makers.
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21

Ichwanda, A. S., H. Irham, Ikah N. P. Permanasari, M. Evita, W. Srigutomo, I. Meilano, A. Setiawan et al. "A Fuzzy Decision in Volcano Warning System Forecast". IOP Conference Series: Earth and Environmental Science 830, n. 1 (1 settembre 2021): 012031. http://dx.doi.org/10.1088/1755-1315/830/1/012031.

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Abstract (sommario):
Abstract The volcanic warning system in Indonesia is divided into four levels namely normal, waspada, siaga and awas. Based on the setting above, a study is needed to design a volcanic activity forecast system using temperature sensors, SO2, CO2 concentration, as well as vibration. The formulation of determining the conditions of volcanic activity is carried out by using fuzzy logic. Volcanic activity measurements are carried out in real time and continuously. Fuzzy logic has been used in the process of determining alert level of volcanic activity based on measured parameters. There are 53 fuzzy rules to determine volcano activity. Best predictions come from the combination of all sensors into a volcano monitoring and forecast system.
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22

Ichwanda, A. S., H. Irham, Ikah N. P. Permanasari, M. Evita, W. Srigutomo, I. Meilano, A. Setiawan et al. "A Fuzzy Decision in Volcano Warning System Forecast". IOP Conference Series: Earth and Environmental Science 830, n. 1 (1 settembre 2021): 012031. http://dx.doi.org/10.1088/1755-1315/830/1/012031.

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Abstract (sommario):
Abstract The volcanic warning system in Indonesia is divided into four levels namely normal, waspada, siaga and awas. Based on the setting above, a study is needed to design a volcanic activity forecast system using temperature sensors, SO2, CO2 concentration, as well as vibration. The formulation of determining the conditions of volcanic activity is carried out by using fuzzy logic. Volcanic activity measurements are carried out in real time and continuously. Fuzzy logic has been used in the process of determining alert level of volcanic activity based on measured parameters. There are 53 fuzzy rules to determine volcano activity. Best predictions come from the combination of all sensors into a volcano monitoring and forecast system.
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23

Dussauge-Peisser, C., A. Helmstetter, J. R. Grasso, D. Hantz, P. Desvarreux, M. Jeannin e A. Giraud. "Probabilistic approach to rock fall hazard assessment: potential of historical data analysis". Natural Hazards and Earth System Sciences 2, n. 1/2 (30 giugno 2002): 15–26. http://dx.doi.org/10.5194/nhess-2-15-2002.

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Abstract. We study the rock fall volume distribution for three rock fall inventories and we fit the observed data by a power-law distribution, which has recently been proposed to describe landslide and rock fall volume distributions, and is also observed for many other natural phenomena, such as volcanic eruptions or earthquakes. We use these statistical distributions of past events to estimate rock fall occurrence rates on the studied areas. It is an alternative to deterministic approaches, which have not proved successful in predicting individual rock falls. The first one concerns calcareous cliffs around Grenoble, French Alps, from 1935 to 1995. The second data set is gathered during the 1912–1992 time window in Yosemite Valley, USA, in granite cliffs. The third one covers the 1954–1976 period in the Arly gorges, French Alps, with metamorphic and sedimentary rocks. For the three data sets, we find a good agreement between the observed volume distributions and a fit by a power-law distribution for volumes larger than 50 m3 , or 20 m3 for the Arly gorges. We obtain similar values of the b exponent close to 0.45 for the 3 data sets. In agreement with previous studies, this suggests, that the b value is not dependant on the geological settings. Regarding the rate of rock fall activity, determined as the number of rock fall events with volume larger than 1 m3 per year, we find a large variability from one site to the other. The rock fall activity, as part of a local erosion rate, is thus spatially dependent. We discuss the implications of these observations for the rock fall hazard evaluation. First, assuming that the volume distributions are temporally stable, a complete rock fall inventory allows for the prediction of recurrence rates for future events of a given volume in the range of the observed historical data. Second, assuming that the observed volume distribution follows a power-law distribution without cutoff at small or large scales, we can extrapolate these predictions to events smaller or larger than those reported in the data sets. Finally, we discuss the possible biases induced by the poor quality of the rock fall inventories, and the sensibility of the extrapolated predictions to variations in the parameters of the power law.
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24

Auguścik-Górajek, Justyna, e Marek Nieć. "The Variability of Mercury Content in Bituminous Coal Seams in the Coal Basins in Poland". Resources 9, n. 11 (30 ottobre 2020): 127. http://dx.doi.org/10.3390/resources9110127.

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Abstract (sommario):
The mercury content in bituminous coal in Poland varies depending on the coal basin. The highest of its concentrations are recorded in the Lower Silesian Coal Basin where this may be the result of the volcanic activity reported there. A much lower average of Hg content was recorded in Lublin and the Upper Silesian Coal Basins (LCB and USCB), although it was higher in the former. A higher mercury concentration in the LCB is probably related to the zone of supposed deep disturbances, named the Karpinsky lineament. Most published works present the data on the mercury content in the bulk of mined coal. The preliminary assessment of mercury content in coal seams indicates that it varies considerably between and within them. It is bound to the presence of arsenic-bearing iron sulfides. Concentration of mercury in small zones of limited extent suggests it was introduced by migrating fluids. The knowledge of mercury content distribution in coal seams would improve the prediction of its content in the mined coal and allow better management of produced coal quality with the aim of reducing mercury emission to the atmosphere as a result of coal combustion.
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25

Harrington, J. B. "Climatic change: a review of causes". Canadian Journal of Forest Research 17, n. 11 (1 novembre 1987): 1313–39. http://dx.doi.org/10.1139/x87-206.

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Abstract (sommario):
The earth's climate is constantly changing. Climatic change is effected by many factors: the influence of continental drift, variations in solar intensity, volcanism, the impact of meteors and comets, changes in the earth's orbital parameters, ice accumulation and depletion, variations in oceanic circulations and chemistry, changes in terrestrial and aquatic life, and changes in atmospheric composition and circulation. Despite these influences, many of them large, and despite changes in the sun's radiant intensity over the past 4.5 billion years, the average temperature of the earth's surface has remained remarkably constant, hovering near 15 °C. This implies the presence of strong negative feedbacks reacting to any major environmental change. During the past century, man's influence on his environment has been increasing at an unprecedented rate. Under this influence, and particularly because of the effect of the so-called "greenhouse gases," the global mean temperature is expected to rise approximately 2.5 °C by the middle of the 21st century. There remains a degree of uncertainty in this prediction because of unresolved problems in estimating various positive and negative feedback mechanisms in air, earth, ocean, ice, and vegetation interaction and in the unknown magnitude of volcanic activity. The finest numerical models and the fastest computers are, at present, inadequate to resolve all of the problems. However, the best scientific evidence points to a return by the middle of the 21st century to a climate similar to that of the climatic optimum 5000–6000 years ago. The degree of confidence in the direction, speed, and magnitude of the impending climatic change is sufficient that affected agencies should be actively mapping strategies to respond most advantageously to the expected changes. This is particularly true of forestry in Canada where climatic changes are expected to be large and the lifetime of current plantings will extend well into the period of anticipated change.
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26

Sakuno, Yuji. "Trial of Chemical Composition Estimation Related to Submarine Volcano Activity Using Discolored Seawater Color Data Obtained from GCOM-C SGLI. A Case Study of Nishinoshima Island, Japan, in 2020". Water 13, n. 8 (16 aprile 2021): 1100. http://dx.doi.org/10.3390/w13081100.

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This study aims to develop the relational equation between the color and chemical composition of discolored seawater around a submarine volcano, and to examine its relation to the volcanic activity at Nishinoshima Island, Japan, in 2020, using the model applied by atmospheric corrected reflectance 8 day composite of GCOM-C SGLI. To achieve these objectives, the relational equation between the RGB value of the discolored seawater in the submarine volcano and the chemical composition summarized in past studies was derived using the XYZ colorimetric system. Additionally, the relationship between the volcanic activity of the island in 2020 and the chemical composition was compared in chronological order using the GCOM-C SGLI data. The following findings were obtained. First, a significant correlation was observed between the seawater color (x) calculated by the XYZ colorimetric system and the chemical composition such as (Fe + Al)/Si. Second, the distribution of (Fe + Al)/Si in the island, estimated from GCOM-C SGLI data, fluctuated significantly just before the volcanic activity became active (approximately one month prior). These results suggest that the chemical composition estimation of discolored seawater using SGLI data may be a powerful tool in predicting submarine volcanic activity.
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27

Gahramanov, G. N., e F. N. Kerimov. "The role of mud volcanism in prediction of oil-gas bearing content in deep layers of Meso-Cenozoic sediment complex of South Caspian megabasin". Azerbaijan Oil Industry, n. 06 (15 giugno 2022): 17–23. http://dx.doi.org/10.37474/0365-8554/2022-6-7-17-23.

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Abstract (sommario):
While conducting exploration surveys for new hydrocarbon fields in oil-gas bearing basins of the world, the data on the mud volcanoes in the area and their explosion is widely used. As the stage of initial activity of mud volcanoes, the source of generation, the product of explosion etc. are associated with the deep layers (7–8 km) of the Earth, this process is an essential source of information for exploration surveys. One of the original aspects of the South Caspian basin is the great amount of mud volcanoes. The study of the composition of gas masses released into the atmosphere as a result of explosion of mud volcanoes enables to make objective forecast on the gas generation zones on the deposition cover of the area and the oil-gas bearing potential as well. By the distribution areal the mud volcanoes predominantly cover oil-gas bearing zones. Thus, there are mud volcanoes on sixty basins from existing 252 oil-gas bearing zones in sedimentation basin of the Earth. Although the generation source of a great deal of mud volcanoes in Azerbaijan is principally associated with Paleogen-Neogen sedimentation complexes, a specific part of volcanic gases is supposed to belong to the Cretaceous-Jurassic sedimentation complexes (8−10 km), which increases the probability of existence of formation sources for hydrocarbon in these complexes.
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28

Goldberd Harmuda Duva Sinaga, Switamy Angnitha Purba e Ady Frenly Simanullang. "Coulomb Stress Analysis And Monte Carlo Simulation In Predicting Sinabung Pyroclastic Flow". World Journal of Advanced Research and Reviews 13, n. 1 (30 gennaio 2022): 781–92. http://dx.doi.org/10.30574/wjarr.2022.13.1.0085.

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Sinabung is a small stratovolcano located in northern Sumatra about 50 km northwest of the Toba caldera. On August 27, 2010, it was confirmed that Sinabung experienced a phreatic eruption for the first time in history. Initially the eruption formed a lava dome that fell out on January 10, 2014 forming pyroclastic density currents. An increase in pore fluid pressure in the crust supports Coulomb Failure Friction. Positive coulomb stress values ​​are thought to trigger Sinabung activity. The research uses a combination of Monte Carlo simulation to predict the next earthquake parameters and coulomb stress analysis to determine the direction and value of stress . The Monte Carlo simulation produces earthquake parameter prediction, longitude 98o latitude 3.175o depth 104.5 meters, Mw 6.0, strike 28.125 o, slip 42o, dip 44.17o. Coulomb Stress analysis of the combined 2001-2021 earthquake data produces an average coulomb value of 0.24 bar, 0.14 bar shear, 0.25 bar normal and the direction of the stress vector to the southwest of Mount Sinabung. The results of the combined coulomb stress analysis and Monte Carlo simulation predict the direction of pyroclastic flows to the northeast, east, and southeast of Mount Sinabung, in accordance with the direction that is inversely proportional to positive stress so that the area needs to receive early warning of volcanic eruption natural disasters in 2022.
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29

Litvinenko, Larisa, e Victoria Litvinenko. "Modern warming, medieval and ancient optimums as the result of orbital changes in the Earth-Moon-Sun system". E3S Web of Conferences 210 (2020): 02008. http://dx.doi.org/10.1051/e3sconf/202021002008.

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Abstract (sommario):
The root cause of modern climate warming is the influence of gravitational forces on the geospheres of our planet, determined by the orbital configuration of the Earth-Moon-Sun system. The annual changes in the position of the total vector of gravitational forces in space visually reflects the movement of the shadow cone of solar eclipses around the globe. The aim and novelty of the study is to identify the relationship between the number of years with four to five polar eclipses (in periods of pessimums, their number reaches 15-17 years, and in periods of optimums – 2-7 years in a century) and glaciation processes, such as the Fernau fluctuation, Late Antique Little Ice Age, or processes of warming and degradation of glaciers in the Roman and Medieval optimums. The research methods were study, generalization of materials, data synthesis, logical and graphical analysis. The anthropogenic causes of modern warming, which will last until the middle of the 22nd century, are secondary. In the second half of the 22nd century, and throughout the entire 24th century, the advance of the alpine glaciers will be associated with the conditions of the climatic pessimum. Solar activity, planetary factors and processes - volcanic activity, current intensity, heat transfer with the World Ocean – can noticeably strengthen or weaken both the manifestation of optimums and pessimums. The results of the study, taking into account other factors, can be used in the retroanalysis of the periods of glaciation in centuries before the Common Era and the prediction of them in the future.
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30

Man, Yuning. "Factor analysis and countermeasures for global warming based on data science methods". Applied and Computational Engineering 58, n. 1 (30 aprile 2024): 222–30. http://dx.doi.org/10.54254/2755-2721/58/20240725.

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Abstract (sommario):
In recent years, the frequent and intensifying occurrence of extreme weather events such as heatwaves, floods, and storms worldwide has led scientists and policymakers to be increasingly concerned about the phenomenon of global warming. The global average temperature has steadily risen over the past few decades, and 2015-2022 has been identified as the warmest years on record. Taking global warming as the research object, the main problem is to find out the factors affecting climate change. The article predicts the global average temperature of the future and builds a model to analyse the relationship between global average temperature, time, location and the factors affecting climate change. The prediction models of ARMIA and EEMD-LSTM were built, and the model with the best fit was obtained after several iterations of tuning and trial optimization. The results showed that Flood, Storm, and Extreme temperature, had a high correlation with the global average temperature. The data of greenhouse gas indicators such as CO2, NO, and CH4, and catastrophes such as earthquakes, Volcanic activity, and wildfires have objective effects on global warming. Random forest regression model pairs were developed, and analysis of the importance of each component to the model showed that CO2 concentration and CH4 concentration had significant effects on global average temperature. Propose measures that can curb or slow down global warming.
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31

Khavroshkin, O. B., S. A. Fedotov, V. V. Tsyplakov e A. N. Boiko. "Volcanology and new geophysics: reality and prospects for example Yellowstone volcano". Вулканология и сейсмология, n. 1 (4 marzo 2019): 25–35. http://dx.doi.org/10.31857/s0203-03062019125-35.

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Abstract (sommario):
The dynamic portrait of Yellowstone volcano activity in the form of detailed analysis of key parameters and in real time is presented. Some preliminary findings show that active volcanoes are energetically open systems with a strong influence of the external astrophysical component, primarily solar muon and neutrino fluxes. This should be taken into account when predicting their activity. The astrophysical component of activity may be one of the main mechanisms synchronizing the state of supervolcanoes. The astrophysical component of volcanic activity can exist in other volcanoes of the terrestrial planets of the Solar system, which also experience the synchronizing effects of the solar neutrino flux, that is, the planets of the Solar system can be found to have common rhythms of volcanic activity.
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32

Khavroshkin, O. B., S. A. Fedotov, V. V. Tsyplakov e A. N. Boiko. "Volcanology and new geophysics: reality and prospects for example Yellowstone volcano". Вулканология и сейсмология, n. 1 (4 marzo 2019): 25–35. http://dx.doi.org/10.31857/s0205-96142019125-35.

Testo completo
Abstract (sommario):
The dynamic portrait of Yellowstone volcano activity in the form of detailed analysis of key parameters and in real time is presented. Some preliminary findings show that active volcanoes are energetically open systems with a strong influence of the external astrophysical component, primarily solar muon and neutrino fluxes. This should be taken into account when predicting their activity. The astrophysical component of activity may be one of the main mechanisms synchronizing the state of supervolcanoes. The astrophysical component of volcanic activity can exist in other volcanoes of the terrestrial planets of the Solar system, which also experience the synchronizing effects of the solar neutrino flux, that is, the planets of the Solar system can be found to have common rhythms of volcanic activity.
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33

Kent, Adam J. R., Christy B. Till e Kari M. Cooper. "Start me up: The relationship between volcanic eruption characteristics and eruption initiation mechanisms". Volcanica 6, n. 2 (17 agosto 2023): 161–72. http://dx.doi.org/10.30909/vol.06.02.161172.

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Abstract (sommario):
Understanding the processes that initiate volcanic eruptions after periods of quiescence are of paramount importance to interpreting volcano monitoring signals and mitigating volcanic hazards. However, studies of eruption initiation mechanisms are rarely systematically applied to high-risk volcanoes. Studies of erupted materials provide important insight into eruption initiation, as they provide direct insight into the physical and chemical changes that occur in magma reservoirs prior to eruptions, but are also often underutilized. Petrologic and geochemical studies can also constrain the timing of processes involved in eruption initiation, and the time that might be expected to elapse between remote detection of increased activity and eventual eruption. A compilation and analysis of literature data suggests that there are statistical differences in the composition, volume, style and timescales between eruptions initiated by different mechanisms. Knowledge of the processes that initiate eruptions at a given volcano may thus have significant predictive power.
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34

Takahashi, Hiroaki. "Real-Time Eruption Magnitude Estimation from Far-Field Geodetic Data: A Proposal for Volcanic Early Warning". Journal of Disaster Research 3, n. 4 (1 agosto 2008): 252–60. http://dx.doi.org/10.20965/jdr.2008.p0252.

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Abstract (sommario):
Recent developments in dense geodetic observation of volcanoes have enabled us to handle data in real-time. Monitoring agencies detect volcano unrest using numerous instruments and quickly broadcast volcanic activity alerts but based on little quantitative information. Residents on volcanoes seek predictive, practical, and reliable alerts including place, time, and magnitude directly linked to disaster mitigation activities. A strategy I proposed in this study answers the question of the magnitude of a foreseen eruption. Far-field displacements by geodetic instruments provide the signals of deflating magma reservoirs, and may give predictive maximum magnitude Mvpof a looming eruption. This may play an important role in antidisaster measures because it is the parameter most determinate for evacuation. Continuous monitoring of Mvpmay also yield valuable information for judging the termination of an eruption because its stagnation indicates magma feeding disconnection from reservoir to shallower part. I believe that predictive volcanic early warnings with quantitative Mvpcan provide truly effective, practical information to residents and local governments potentially affected by active volcanoes.
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35

ΛΥΚΟΥΔΗ, Ε. "Geomorphic evolution of the upper reaches of the drainage basin of Acheloos river". Bulletin of the Geological Society of Greece 34, n. 1 (1 gennaio 2001): 397. http://dx.doi.org/10.12681/bgsg.17333.

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Abstract (sommario):
The scope of this study work is to give an insight into the dynamic processes which shape the relief in the drainage basin of the upper reaches the Acheloos river, so that the geomorphological and geodynamical evolution of the region in the past can be approached, together with a possible prediction. For this reason, the relationships between the relief and the endogenic and exogenic factors are sought. The investigated area is made up of geological formations that belong to the zones: "Ionian" (inner Ionian zone), "Gavrovo", "Pindos" and "Hyperpindos". There are also younger rocks (postalpine formations), together with some volcanic rocks. The main stream segment of Acheloos river was formed in the Upper-Middle Miocene, after the deposition of the flysch of "Gavrovo" and the tectonism of the zone. The structures were cut to a large extent by trace-slip faults, striking ENE-WSW, during the Middle-Upper Miocene. At the same time (Lower Miocene - Plio-Quaternary), in NW-Greece, is observed a horizontal clockwise rotation (45°). Finally, the region shows an expanding movement from North to South. Due to the above tectonic activity, the drainage basin shows a monoclinic structure with a westward displacement of the drainage pattern. The displacement increases from North to South. The displacement of the drainage pattern is also favoured by the presence of erodible rocks in the western part (flysch of "Gavrovo") and the general eastward dip of the strata. Neotectonic activity controls the river up to date, as it is inferred from the orientation of the stream segments, which follow the tectonic structure (lithological boundaries, faults, thrusts). The drainage pattern appears to be in an early mature stage. According to the quantitative geomorphological analysis data, the drainage pattern (mainly the west part of it) is in an unstable dynamic status. During Plio-Quaternary there were a few rejuvenating episodes, due to tectonic and climate changes. The present rejuvenated stage, which is more obvious in the southwestern part of the investigated area, is supported by morphotectonic data. Among them, the most remarkable are: a)the steep slopes (30-60 %), b)the negative deviation of "cummulative" area compared to ideal values, c)the slope flexions, which separate the new lower level from the old higher one.
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36

Morgenstern, U., C. J. Daughney, G. Leonard, D. Gordon, F. M. Donath e R. Reeves. "Using groundwater age to understand sources and dynamics of nutrient contamination through the catchment into Lake Rotorua, New Zealand". Hydrology and Earth System Sciences Discussions 11, n. 8 (27 agosto 2014): 9907–60. http://dx.doi.org/10.5194/hessd-11-9907-2014.

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Abstract (sommario):
Abstract. The water quality of Lake Rotorua has declined continuously over the past 50 yr despite mitigation efforts over recent decades. Delayed response of the groundwater discharges to historic land-use intensification 50 yr ago was the reason suggested by early tritium measurements, which indicated large transit times through the groundwater system. We use the isotopic and chemistry signature of the groundwater for detailed understanding of the origin, fate, flow pathways, lag times, and future loads of contaminants. A unique set of high-quality tritium data over more than four decades, encompassing the time when the tritium spike from nuclear weapons testing moved through the groundwater system, allows us to determine detailed age distribution parameters of the water discharging into Lake Rotorua. The Rotorua volcanic groundwater system is complicated due to the highly complex geology that has evolved through volcanic activity. Vertical and steeply-inclined geological contacts preclude a simple flow model. The extent of the Lake Rotorua groundwater catchment is difficult to establish due to the deep water table in large areas, combined with inhomogeneous groundwater flow patterns. Hierarchical cluster analysis of the water chemistry parameters provided evidence of the recharge source of the large springs near the lake shore, with discharge from the Mamaku ignimbrite through lake sediment layers. Groundwater chemistry and age data show clearly the source of nutrients that cause lake eutrophication, nitrate from agricultural activities and phosphate from geologic sources. With a naturally high phosphate load reaching the lake continuously via all streams, the only effective way to limit algae blooms and improve lake water quality in such environments is by limiting the nitrate load. The groundwater in the Rotorua catchment, once it has passed through the soil zone, shows no further decrease in dissolved oxygen, indicating absence of electron donors in the aquifer that could facilitate microbial denitrification reactions. Nitrate from land-use activities that leaches out of the root zone of agricultural land into the deeper part of the groundwater system must be expected to travel with the groundwater to the lake. The old age and the highly mixed nature of the water discharges imply a very slow and lagged response of the streams and the lake to anthropogenic contaminants in the catchment, such as nitrate. Using the age distribution as deduced from tritium time series data measured in the stream discharges into the lake allows prediction of future nutrient loads from historic land-use activities 50 yr ago. For Hamurana Stream, the largest stream to Lake Rotorua, it takes more than a hundred years for the groundwater-dominated stream discharge to adjust to changes in land-use activities. These time scales apply to activities that cause contamination, but also to remediation action.
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37

Dashore, Nilesh. "Fuzzy logic based model for predicting volcanic activity". Indian Journal of Science and Technology 3, n. 7 (20 luglio 2010): 759–62. http://dx.doi.org/10.17485/ijst/2010/v3i7.5.

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38

Morgenstern, U., C. J. Daughney, G. Leonard, D. Gordon, F. M. Donath e R. Reeves. "Using groundwater age and hydrochemistry to understand sources and dynamics of nutrient contamination through the catchment into Lake Rotorua, New Zealand". Hydrology and Earth System Sciences 19, n. 2 (5 febbraio 2015): 803–22. http://dx.doi.org/10.5194/hess-19-803-2015.

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Abstract (sommario):
Abstract. The water quality of Lake Rotorua has steadily declined over the past 50 years despite mitigation efforts over recent decades. Delayed response of the groundwater discharges to historic land-use intensification 50 years ago was the reason suggested by early tritium measurements, which indicated large transit times through the groundwater system. We use the isotopic and chemistry signature of the groundwater for detailed understanding of the origin, fate, flow pathways, lag times and future loads of contaminants. A unique set of high-quality tritium data over more than four decades, encompassing the time when the tritium spike from nuclear weapons testing moved through the groundwater system, allows us to determine detailed age distribution parameters of the water discharging into Lake Rotorua. The Rotorua volcanic groundwater system is complicated due to the highly complex geology that has evolved through volcanic activity. Vertical and steeply inclined geological contacts preclude a simple flow model. The extent of the Lake Rotorua groundwater catchment is difficult to establish due to the deep water table in large areas, combined with inhomogeneous groundwater flow patterns. Hierarchical cluster analysis of the water chemistry parameters provided evidence of the recharge source of the large springs near the lake shore, with discharge from the Mamaku ignimbrite through lake sediment layers. Groundwater chemistry and age data show clearly the source of nutrients that cause lake eutrophication, nitrate from agricultural activities and phosphate from geologic sources. With a naturally high phosphate load reaching the lake continuously via all streams, the only effective way to limit algae blooms and improve lake water quality in such environments is by limiting the nitrate load. The groundwater in the Rotorua catchment, once it has passed through the soil zone, shows no further decrease in dissolved oxygen, indicating an absence of bioavailable electron donors along flow paths that could facilitate microbial denitrification reactions. Nitrate from land-use activities that leaches out of the root zone of agricultural land into the deeper part of the groundwater system must be expected to travel with the groundwater to the lake. The old age and the highly mixed nature of the water discharges imply a very slow and lagged response of the streams and the lake to anthropogenic contaminants in the catchment, such as nitrate. Using the age distribution as deduced from tritium time series data measured in the stream discharges into the lake allows prediction of future nutrient loads from historic land-use activities 50 years ago. For Hamurana Stream, the largest stream to Lake Rotorua, it takes more than a hundred years for the groundwater-dominated stream discharge to adjust to changes in land-use activities. About half of the currently discharging water is still pristine old water, and after this old water is completely displaced by water affected by land use, the nitrogen load of Hamurana Stream will approximately double. These timescales apply to activities that cause contamination, but also to remediation action.
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39

Roukounakis, Nikolaos, Panagiotis Elias, Pierre Briole, Dimitris Katsanos, Ioannis Kioutsioukis, Athanassios A. Argiriou e Adrianos Retalis. "Tropospheric Correction of Sentinel-1 Synthetic Aperture Radar Interferograms Using a High-Resolution Weather Model Validated by GNSS Measurements". Remote Sensing 13, n. 12 (9 giugno 2021): 2258. http://dx.doi.org/10.3390/rs13122258.

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Abstract (sommario):
Synthetic Aperture Radar Interferometry (InSAR) is a space geodetic technique used for mapping deformations of the Earth’s surface. It has been developed and used increasingly during the last thirty years to measure displacements produced by earthquakes, volcanic activity and other crustal deformations. A limiting factor to this technique is the effect of the troposphere, as spatial and temporal variations in temperature, pressure, and relative humidity introduce significant phase delays in the microwave imagery, thus “masking” surface displacements due to tectonic or other geophysical processes. The use of Numerical Weather Prediction (NWP) models as a tropospheric correction method in InSAR can tackle several of the problems faced with other correction techniques (such as timing, spatial coverage and data availability issues). High-resolution tropospheric modelling is particularly useful in the case of single interferograms, where the removal of the atmospheric phase screen (and especially the highly variable turbulent component) can reveal large-amplitude deformation signals (as in the case of an earthquake). In the western Gulf of Corinth, prominent topography makes the removal of both the stratified and turbulent atmospheric phase screens a challenging task. Here, we investigate the extent to which a high-resolution WRF 1-km re-analysis can produce detailed tropospheric delay maps of the required accuracy by coupling its output (in terms of Zenith Total Delay or ZTD) with the vertical delay component in GNSS measurements. The model is operated with varying physical parameterization in order to identify the best configuration, and validated with GNSS zenithal tropospheric delays, providing a benchmark of real atmospheric conditions. We correct sixteen Sentinel-1A interferograms with differential delay maps at the line-of-sight (LOS) produced by WRF re-analysis. In most cases, corrections lead to a decrease in the phase gradient, with average root-mean-square (RMS) and standard deviation (SD) reductions in the wrapped phase of 6.0% and 19.3%, respectively. Results suggest a high potential of the model to reproduce both the long-wavelength stratified atmospheric signal and the short-wave turbulent atmospheric component which are evident in the interferograms.
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40

Falanga, Mariarosaria, Enza De Lauro, Simona Petrosino e Salvatore De Martino. "Interaction between seismicity and deformation on different time scales in volcanic areas: Campi Flegrei and Stromboli". Advances in Geosciences 52 (5 dicembre 2019): 1–8. http://dx.doi.org/10.5194/adgeo-52-1-2019.

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Abstract (sommario):
Abstract. We study oscillations recorded at Stromboli and Campi Flegrei by different sensors: seismometers, strainmeters and tiltmeters. We examine both the high-frequency (>0.5 Hz) portion of the spectrum and very long period signals up to tidal scales. In this context, seismicity and deformation are investigated on different time scales (from minutes to days/years) in order to identify the basic elements of their interaction, whose understanding should provide new insights on the predictive models. In this work, the strict relation of tides and volcanic processes is shown. At Stromboli, indeed the transition from the stationary phase to the non-stationary phase seems to have a tidal precursor that is related to the duration of the crisis. The subsequent volcanic activity is interpreted as the response of the volcano to restore the equilibrium condition. The moveout from equilibrium produces, first, variations in the standard statistics of explosions, then leads to effusive stage and to a pressure drop in the shallow feeding system. That process induces the nucleation of a gas bubble and the excitation of low frequencies. Campi Flegrei seismicity shows a correlation between the diurnal solar solid tide and the energy released by the long period signals, indicating that the whole mechanism is modulated on a tidal scale. In other words, in the case of Stromboli, a departure from the equilibrium state is marked by solid tide variations in a certain frequency band. On the other hand, at Campi Flegrei diurnal to annual solid tides modulate an increase of volcanic activity.
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41

Sakuno, Yuji, Sakito Hirao e Naokazu Taniguchi. "Quantitatively Mapping Discolored Seawater around Submarine Volcanoes Using Satellite GCOM-C SGLI Data: A Case Study of the Krakatau Eruption in Indonesia in December 2018". GeoHazards 4, n. 2 (3 aprile 2023): 107–20. http://dx.doi.org/10.3390/geohazards4020007.

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Abstract (sommario):
The final goal of this paper is to contribute to the difficult task of understanding and forecasting submarine volcanic eruption activity by proposing a method to quantify discolored water. To achieve this purpose, we quantitatively analyzed the discolored seawater seen before and after the eruption of the marine environment around the Indonesian submarine volcano “Anak Krakatau”, which erupted at the end of December 2018, from the viewpoint of the “dominant wavelength”. The atmospherically corrected COM-C SGLI data for 17 periods from the eruption from October 2018 to March 2019 were used. As a result, the following three main items were found. First, the average ± standard deviation of the entire dominant wavelength was 497 nm ± 2 nm before the eruption and 515 nm ± 35 nm after the eruption. Second, the discolored water area around the island derived from SGLI was detected from the contour line with dominant wavelengths of 500 nm and 560 nm. Third, the size of a dominant wavelength of 500 nm or more in the discolored water areas changed in a complicated manner within the range of almost 0 to 35 km2. The area of the dominant wavelength of 500 nm or more slightly increased just before the eruption. Finally, it was proven that the “dominant wavelength” from the SGLI proposed in this paper can be a very effective tool in understanding or predicting submarine volcanic activity.
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42

Muravyev, A. "Geothermal monitoring as a way to predict volcanic eruptions and estimate geothermal energy resources". Georesursy 20, n. 4 (30 novembre 2018): 413–22. http://dx.doi.org/10.18599/grs.2018.4.413-422.

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Abstract (sommario):
Geothermal monitoring is an effective tool for predicting volcanic eruptions, as well as for assessing the geothermal energy potential of geothermal areas. Increased magmatic activity, an indicator of which is the penetration of hot volcanic gases through faults, has been observed in recent years on the Elbrus volcano. Since Elbrus is a year-round resort of world importance, in order to control volcanic and seismic activity, forecast and reduce the risks of eruption and earthquakes, it is recommended to drill a observation well on the slope of Elbrus with the installation of an underground fiber-optic system for temperature and pressure monitoring. In combination with microseismic, gravimetric and inclinometric observations, satellite IR imaging and geochemical gas testing, the continuously obtained information on the thermodynamic conditions of the subsoil will provide a reliable complex for the operational forecast of natural geophysical disasters. Utilization of the geothermal energy of the magma chamber in the artificial circulation systems of small GeoPPs, water injection from the surface and obtaining superheated water and steam from producing wells will reduce the risks of eruption and at the same time provide the resort with environmentally friendly thermal and electric power. Technological justification for the construction of a GeoPP will also require exploratory drilling to the area of ​​hot rocks, therefore information on the distribution of temperature and pressure along the wellbore is doubly valuable. In geothermal fields that are under development, to assess the spatial heterogeneity of the filtration characteristics can be a useful method of “thermal interference testing” – as a complement or alternative to hydrodynamic interference testing. It is recommended to conduct such an experiment at the North Mutnovsky geothermal field.
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43

Burl Henry. "The definitive cause of La Nina and El Nino events". World Journal of Advanced Research and Reviews 17, n. 1 (30 gennaio 2023): 908–11. http://dx.doi.org/10.30574/wjarr.2023.17.1.0124.

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Abstract (sommario):
Rather than being strictly random events, it has been proven that all La Ninas and El Ninos are caused by the increase or decrease of reflective SO2 aerosols in Earth’s atmosphere, from both volcanic eruptions and industrial activity. Although volcanic eruptions are random events, an eruption usually signifies a forthcoming La Nina/El Nino cycle, and thus can have some predictive value.
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44

Brown, Geoff, Hazel Rymer, John Dowden, Phiroze Kapadia, David Stevenson, Jorge Barquero e Louis D. Morales. "Energy budget analysis for Poás crater lake: implications for predicting volcanic activity". Nature 339, n. 6223 (giugno 1989): 370–73. http://dx.doi.org/10.1038/339370a0.

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45

Black, Benjamin A., Jean-François Lamarque, Daniel R. Marsh, Anja Schmidt e Charles G. Bardeen. "Global climate disruption and regional climate shelters after the Toba supereruption". Proceedings of the National Academy of Sciences 118, n. 29 (6 luglio 2021): e2013046118. http://dx.doi.org/10.1073/pnas.2013046118.

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Abstract (sommario):
The Toba eruption ∼74,000 y ago was the largest volcanic eruption since the start of the Pleistocene and represents an important test case for understanding the effects of large explosive eruptions on climate and ecosystems. However, the magnitude and repercussions of climatic changes driven by the eruption are strongly debated. High-resolution paleoclimate and archaeological records from Africa find little evidence for the disruption of climate or human activity in the wake of the eruption in contrast with a controversial link with a bottleneck in human evolution and climate model simulations predicting strong volcanic cooling for up to a decade after a Toba-scale eruption. Here, we use a large ensemble of high-resolution Community Earth System Model (CESM1.3) simulations to reconcile climate model predictions with paleoclimate records, accounting for uncertainties in the magnitude of Toba sulfur emissions with high and low emission scenarios. We find a near-zero probability of annual mean surface temperature anomalies exceeding 4 °C in most of Africa in contrast with near 100% probabilities of cooling this severe in Asia and North America for the high sulfur emission case. The likelihood of strong decreases in precipitation is low in most of Africa. Therefore, even Toba sulfur release at the upper range of plausible estimates remains consistent with the muted response in Africa indicated by paleoclimate proxies. Our results provide a probabilistic view of the uneven patterns of volcanic climate disruption during a crucial interval in human evolution, with implications for understanding the range of environmental impacts from past and future supereruptions.
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46

Manjón-Cabeza Córdoba, Antonio, e Maxim D. Ballmer. "The role of edge-driven convection in the generation ofvolcanism – Part 2: Interaction with mantle plumes, applied to the Canary Islands". Solid Earth 13, n. 10 (21 ottobre 2022): 1585–605. http://dx.doi.org/10.5194/se-13-1585-2022.

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Abstract (sommario):
Abstract. In the eastern Atlantic Ocean, several volcanic archipelagos are located close to the margin of the African continent. This configuration has inspired previous studies to suggest an important role of edge-driven convection (EDC) in the generation of intraplate magmatism. In a companion paper (Manjón-Cabeza Córdoba and Ballmer, 2021), we showed that EDC alone is insufficient to sustain magmatism of the magnitude required to match the volume of these islands. However, we also found that EDC readily develops near a step of lithospheric thickness, such as the oceanic–continental transition (“edge”) along the western African cratonic margin. In this work, we carry out 3D numerical models of mantle flow and melting to explore the possible interactions between EDC and mantle plumes. We find that the stem of a plume that rises close to a lithospheric edge is significantly deflected ocean-ward (i.e., away from the edge). The pancake of ponding hot material at the base of the lithosphere is also deflected by the EDC convection cell (either away or towards the edge). The amount of magmatism and plume deflection depends on the initial geometric configuration, i.e., the distance of the plume from the edge. Plume buoyancy flux and temperature also control the amount of magmatism, and influence the style and extent of plume–EDC interaction. Finally, comparison of model predictions with observations reveals that the Canary plume may be significantly affected and deflected by EDC, accounting for widespread and coeval volcanic activity. Our work shows that many of the peculiar characteristics of eastern Atlantic volcanism are compatible with mantle plume theory once the effects of EDC on plume flow are considered.
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47

Abdelkareem, Mohamed, Fathy Abdalla, Samar Y. Mohamed e Farouk El-Baz. "Mapping Paleohydrologic Features in the Arid Areas of Saudi Arabia Using Remote-Sensing Data". Water 12, n. 2 (4 febbraio 2020): 417. http://dx.doi.org/10.3390/w12020417.

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Abstract (sommario):
At present, the Arabian Peninsula is one of the driest regions on Earth; however, this area experienced heavy rainfall in the past thousand years. During this period, catchments received substantial amounts of surface water and sustained vast networks of streams and paleolakes, which are currently inactive. The Advanced Land Observing Satellite (ALOS) Phased Array Type L-band Synthetic Aperture Radar (PALSAR) data reveal paleohydrologic features buried under shallow aeolian deposits in many areas of the ad-Dawasir, Sahba, Rimah/Batin, and as-Sirhan wadis. Optical remote-sensing data support that the middle of the trans-peninsula Wadi Rimah/Batin, which extends for ~1200 km from the Arabian Shield to Kuwait and covers ~200,000 km2, is dammed by linear sand dunes formed by changes in climate conditions. Integrating Landsat 8 Operational Land Imager (OLI), Geo-Eye, Shuttle Radar Topography Mission (SRTM) digital elevation model, and ALOS/PALSAR data allowed for the characterization of paleodrainage reversals and diversions shaped by structural and volcanic activity. Evidence of streams abruptly shifting from one catchment to another is preserved in Wadi ad-Dawasir along the fault trace. Volcanic activity in the past few thousand years in northern Saudi Arabia has also changed the slope of the land and reversed drainage systems. Relics of earlier drainage directions are well maintained as paleoslopes and wide upstream patterns. This study found that paleohydrologic activity in Saudi Arabia is impacted by changes in climate and by structural and volcanic activity, resulting in changes to stream direction and activity. Overall, the integration of radar and optical remote-sensing data is significant for deciphering past hydrologic activity and for predicting potential water resource areas.
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48

Toohey, M., K. Krüger, M. Bittner, C. Timmreck e H. Schmidt. "The impact of volcanic aerosol on the Northern Hemisphere stratospheric polar vortex: mechanisms and sensitivity to forcing structure". Atmospheric Chemistry and Physics 14, n. 23 (9 dicembre 2014): 13063–79. http://dx.doi.org/10.5194/acp-14-13063-2014.

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Abstract (sommario):
Abstract. Observations and simple theoretical arguments suggest that the Northern Hemisphere (NH) stratospheric polar vortex is stronger in winters following major volcanic eruptions. However, recent studies show that climate models forced by prescribed volcanic aerosol fields fail to reproduce this effect. We investigate the impact of volcanic aerosol forcing on stratospheric dynamics, including the strength of the NH polar vortex, in ensemble simulations with the Max Planck Institute Earth System Model. The model is forced by four different prescribed forcing sets representing the radiative properties of stratospheric aerosol following the 1991 eruption of Mt. Pinatubo: two forcing sets are based on observations, and are commonly used in climate model simulations, and two forcing sets are constructed based on coupled aerosol–climate model simulations. For all forcings, we find that simulated temperature and zonal wind anomalies in the NH high latitudes are not directly impacted by anomalous volcanic aerosol heating. Instead, high-latitude effects result from enhancements in stratospheric residual circulation, which in turn result, at least in part, from enhanced stratospheric wave activity. High-latitude effects are therefore much less robust than would be expected if they were the direct result of aerosol heating. Both observation-based forcing sets result in insignificant changes in vortex strength. For the model-based forcing sets, the vortex response is found to be sensitive to the structure of the forcing, with one forcing set leading to significant strengthening of the polar vortex in rough agreement with observation-based expectations. Differences in the dynamical response to the forcing sets imply that reproducing the polar vortex responses to past eruptions, or predicting the response to future eruptions, depends on accurate representation of the space–time structure of the volcanic aerosol forcing.
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49

O'Hara, Daniel, Liran Goren, Roos M. J. van Wees, Benjamin Campforts, Pablo Grosse, Pierre Lahitte, Gabor Kereszturi e Matthieu Kervyn. "Time-varying drainage basin development and erosion on volcanic edifices". Earth Surface Dynamics 12, n. 3 (8 maggio 2024): 709–26. http://dx.doi.org/10.5194/esurf-12-709-2024.

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Abstract (sommario):
Abstract. The erosional state of a landscape is often assessed through a series of metrics that quantify the morphology of drainage basins and divides. Such metrics have been well explored in tectonically active environments to evaluate the role of different processes in sculpting topography, yet relatively few works have applied these analyses to radial landforms such as volcanoes. We quantify drainage basin geometries on volcanic edifices of varying ages using common metrics (e.g., Hack's law, drainage density, and number of basins that reach the edifice summit, as well as basin hypsometry integral, length, width, relief, and average topographic slope). Relating these measurements to the log-mean age of activity for each edifice, we find that drainage density, basin hypsometry, basin length, and basin width quantify the degree of erosional maturity for these landforms. We also explore edifice drainage basin growth and competition by conducting a divide mobility analysis on the volcanoes, finding that young volcanoes are characterized by nearly uniform fluvial basins within unstable configurations that are more prone to divide migration. As basins on young volcanoes erode, they become less uniform but adapt to a more stable configuration with less divide migration. Finally, we analyze basin spatial geometries and outlet spacing on edifices, discovering an evolution in radial basin configurations that differ from typical linear mountain ranges. From these, we present a novel conceptual model for edifice degradation that allows new interpretations of composite volcano histories and provides predictive quantities for edifice morphologic evolution.
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50

Inguaggiato, Salvatore, Fabio Vita, Marianna Cangemi e Lorenzo Calderone. "Changes in CO2 Soil Degassing Style as a Possible Precursor to Volcanic Activity: The 2019 Case of Stromboli Paroxysmal Eruptions". Applied Sciences 10, n. 14 (10 luglio 2020): 4757. http://dx.doi.org/10.3390/app10144757.

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Abstract (sommario):
Paroxysmal explosions are some of the most spectacular evidence of volcanism on Earth and are triggered by the rapid ascent of volatile-rich magma. These explosions often occur in persistently erupting basaltic volcanoes located in subduction zones and represent a major hazard due to the sudden occurrence and wide impact on the neighboring populations. However, the recognition of signals that forecast these blasts remains challenging even in the best-monitored volcanoes. Here, we present the results of the regular monitoring of soil CO2 flux from a fumarole field at the summit of Stromboli (Italy), highlighting that the 2016–2019 period was characterized by two important phases of strong increases of volatile output rate degassing (24 g m2 d−2 and 32 g m2 d−2, respectively) and moreover by significant changes in the degassing style few months before the last paroxysmal explosions occurred in the summer 2019 (3 July and 28 August). Establish that the deep portions of a volcano plumbing system are refilled by new volatiles-rich magma intruding from the mantle is therefore a key factor for forecasting eruptions and helping in recognizing possible precursors of paroxysmal explosions and could be highlighted by the monitoring of soil CO2 flux. The abrupt increase of degassing rate coupled with the strong increase of fluctuating signal (daily natural deviation) recorded during 2019 at Stromboli could be the key to predicting the occurrence of paroxysmal events.
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