Journal articles on the topic 'Fields of Research – 260000 Earth Sciences'
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Chakraborty, Sumit. "Diffusion Studies in Earth and Planetary Sciences." Defect and Diffusion Forum 237-240 (April 2005): 1081–92. http://dx.doi.org/10.4028/www.scientific.net/ddf.237-240.1081.
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The use of atomic diffusion processes to understand the origin and evolution of the Earth and other Planetary systems are briefly reviewed in this paper. I outline some situations to illustrate how diffusion modeling may find varied applications in the Earth and Planetary Sciences. Some possible areas of research are described where advances in Geosciences may benefit researchers interested in diffusion processes in other fields. These include measurement of diffusion rates under high pressures, studies in multicomponent diffusion and modelling of diffusion and point defect related processes in multiphase and multicomponent non-metallic systems. Finally, I outline some areas where input from specialists in other areas may advance knowledge in the Geosciences.
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Annette, Lucy. "International research delivers many rewards." Impact 2021, no. 6 (July 15, 2021): 32–33. http://dx.doi.org/10.21820/23987073.2021.6.32.
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International collaboration in research is not a new concept, but as pressure on research funding increases, project applications for funding must deliver a comprehensive package of well-considered experimental design, impactful research focus and a world-class team. Collaborations with key international leaders in their fields are an excellent way of boosting the credentials of any project, increasing the chances of the group getting funding by opening up their pool of potential funders.
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Xiuzhen Li and Ülo Mander. "Future options in landscape ecology: development and research." Progress in Physical Geography: Earth and Environment 33, no. 1 (February 2009): 31–48. http://dx.doi.org/10.1177/0309133309103888.
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The aim of this brief overview is to highlight some new and promising research fields in landscape ecology, which is essentially an interdisciplinary field of study. We also analyse the development of some classical branches of landscape ecology regarding pattern and process relationships at broad spatial and temporal scales, such as landscape metrics, the influence of anthropogenic factors and global climate change on landscape development, the fragmentation of ecosystems and disturbances of populations, and material and energy cycling in and between ecosystems.
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Hossain, Liaquat, Faezeh Karimi, and Rolf T. Wigand. "Dynamics of a Global Zoonotic Research Network Over 33 Years (1980–2012)." Disaster Medicine and Public Health Preparedness 9, no. 5 (July 27, 2015): 496–503. http://dx.doi.org/10.1017/dmp.2015.58.
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AbstractObjectiveThe increasing rate of outbreaks in humans of zoonotic diseases requires detailed examination of the education, research, and practice of animal health and its connection to human health. This study investigated the collaboration network of different fields engaged in conducting zoonotic research from a transdisciplinary perspective.MethodsExamination of the dynamics of this network for a 33-year period from 1980 to 2012 is presented through the development of a large scientometric database from Scopus. In our analyses we compared several properties of these networks, including density, clustering coefficient, giant component, and centrality measures over time. We also elicited patterns in different fields of study collaborating with various other fields for zoonotic research.ResultsWe discovered that the strongest collaborations across disciplines are formed among the fields of medicine; biochemistry, genetics, and molecular biology; immunology and microbiology; veterinary; agricultural and biological sciences; and social sciences. Furthermore, the affiliation network is growing overall in terms of collaborative research among different fields of study such that more than two-thirds of all possible collaboration links among disciplines have already been formed.ConclusionsOur findings indicate that zoonotic research scientists in different fields (human or animal health, social science, earth and environmental sciences, engineering) have been actively collaborating with each other over the past 11 years. (Disaster Med Public Health Preparedness. 2015;9:496–503)
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Al-Obaidi, Dr Entisar. "The Role of the Media in establishing the Mental Image of Organization’s Reputation." GIS Business 14, no. 6 (December 12, 2019): 643–55. http://dx.doi.org/10.26643/gis.v14i6.15016.
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The use of the concept of a mental image includes several knowledge fields and different scientific disciplines. Its use in contemporary social research has become more apparent in communicative and media studies in general, as well as its abundance in the fields of philosophy, psychology, social psychology and other Knowledge.
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Denis, Antoine, Baudouin Desclee, Silke Migdall, Herbert Hansen, Heike Bach, Pierre Ott, Amani Louis Kouadio, and Bernard Tychon. "Multispectral Remote Sensing as a Tool to Support Organic Crop Certification: Assessment of the Discrimination Level between Organic and Conventional Maize." Remote Sensing 13, no. 1 (December 31, 2020): 117. http://dx.doi.org/10.3390/rs13010117.
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The annual certification of organic agriculture products includes an in situ inspection of the fields declared organic. This inspection is more difficult, time-consuming, and costly for large farms or in production regions located in remote areas. The global objective of this research is to assess how spatial remote sensing may support the organic crop certification process by developing a method that would enable certification bodies to target for priority in situ control crop fields declared as organic but that would show on satellite imagery an appearance closer to conventional fields. For this purpose, the ability of multispectral satellite images to discriminate between organic and conventional maize fields was assessed through the use of a set of four satellite images of different spatial and spectral resolutions acquired at different crop growth stages over a large number of maize fields (32) that are part of an operational farm in Germany. In support of this main objective, a set of in situ measurements (leaf hyperspectral reflectance, chlorophyll, and nitrogen content and dry matter percentage, crop canopy cover, height, wet biomass and dry matter percentage, soil chemical composition) was conducted to characterize the nature of the biochemical and biophysical differences between organic and conventional maize fields. The results of this research showed that highly significant biochemical and biophysical differences between a large number of organic and conventional maize fields may exist at identified crop growth stages and that these differences may be sufficiently pronounced to enable the complete discrimination between crop management modes using satellite images issued from quite common multispectral satellite sensors through the use of spectral or spatial heterogeneity indices. These results are very encouraging and suggest, for the first time, that satellite images could effectively support the organic maize certification process.
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Erdal, D., and O. A. Cirpka. "Joint inference of groundwater-recharge and hydraulic-conductivity fields from head data using the Ensemble-Kalman filter." Hydrology and Earth System Sciences Discussions 12, no. 6 (June 12, 2015): 5565–99. http://dx.doi.org/10.5194/hessd-12-5565-2015.
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Abstract. Regional groundwater flow strongly depends on groundwater recharge and hydraulic conductivity. Both are spatially variable fields, and their estimation is an ongoing topic in groundwater research and practice. In this study, we use the Ensemble Kalman filter as an inversion method to jointly estimate spatially variable recharge and conductivity fields from head observations. The success of the approach strongly depends on the assumed prior knowledge. If the structural assumptions underlying the initial ensemble of the parameter fields are correct, both estimated fields resemble the true ones. However, erroneous prior knowledge may not be corrected by the data. In the worst case, the estimated recharge field resembles the true conductivity field, resulting in a model that meets the observations but has very poor predictive power. The study exemplifies the importance of prior knowledge in the joint estimation of parameters from ambiguous measurements.
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Medyńska-Gulij, Beata, David Forrest, and Paweł Cybulski. "Modern Cartographic Forms of Expression: The Renaissance of Multimedia Cartography." ISPRS International Journal of Geo-Information 10, no. 7 (July 14, 2021): 484. http://dx.doi.org/10.3390/ijgi10070484.
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This article summarizes the Special Issue of “Multimedia Cartography”. We present three main research fields in which multimedia cartography and the study of the effectiveness of multimedia maps are currently taking place. In each of these fields, we describe how published research is embedded in the broader context of map design and user studies. The research refers to contemporary technological trends such as web HTML5 standards, virtual reality, eye tracking, or 3D printing. Efficiency, performance, and usability studies of multimedia maps were also included. The research published in this issue is interdisciplinary. They combine traditional mapping methods with new technologies. They are searching for new places for cartography in, e.g., the environment of computer games. They combine the design of the map with its perception by users.
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Unterbruner, U., S. Hilberg, and I. Schiffl. "Understanding groundwater – students' pre-conceptions and conceptual change by a theory-guided multimedia learning program." Hydrology and Earth System Sciences Discussions 12, no. 11 (November 10, 2015): 11689–737. http://dx.doi.org/10.5194/hessd-12-11689-2015.
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Abstract. Groundwater is a crucial topic in education for sustainable development. Nevertheless, international studies with students of different ages have shown that the basic hydrogeological concept of groundwater defined as water within porous and permeable rocks is not an established everyday notion. Building upon international research a multimedia learning program ("Between the raincloud and the tap") was developed. Insights from the fields of conceptual change research, multimedia research, and the Model of Educational Reconstruction were specifically implemented. Two studies were conducted with Austrian pupils (7th grade) and teacher training students from the fields of biology and geography in order to ascertain the effectiveness of the learning program. Using a quasi-experimental research design, the participants' conceptions and knowledge regarding groundwater were determined in a pre- and post-test. The pupils and students greatly profited from independently working through the learning software. Their knowledge of groundwater increased significantly compared to the control group and there was a highly significant increase in the number of scientifically correct notions of groundwater. The acceptance of the program was also generally very high. The results speak for the fact that theory-guided multimedia learning programs can play an important role in the transfer of research results into the classroom, particularly in science education.
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LOCHER, FABIEN. "The observatory, the land-based ship and the crusades: earth sciences in European context, 1830–50." British Journal for the History of Science 40, no. 4 (September 11, 2007): 491–504. http://dx.doi.org/10.1017/s0007087407000301.
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AbstractThe 1830s and 1840s witnessed a European movement to accumulate data about the terrestrial environment, enterprises including the German and British geomagnetic crusades. This movement was not limited to geomagnetic studies but notably included an important meteorological component. By focusing on observation practices in sedentary and expeditionary contexts, this paper shows how the developing fields of geomagnetism and meteorology were then intimately interlinked. It analyses the circulation and cross-connections of the practices and discourses shared by these two research fields. Departing from a Humboldtian historiography, the paper especially stresses the role of Adolphe Quetelet, director of the Brussels Observatory, whose importance in the development of the earth sciences has until now been largely neglected. It reassesses the involvement of the French scientific community in the British and German geomagnetic crusades, moving beyond the well-known account of Arago's opposition to these undertakings. It is hoped thereby to contribute to a better historical understanding of the renewal of the earth sciences in the second quarter of the nineteenth century.
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Amanipoor, Hakimeh. "PROVIDING A SUBSURFACE RESERVOIR QUALITY MAPS IN OIL FIELDS BY GEOSTATISTICAL METHODS." Geodesy and Cartography 39, no. 4 (December 18, 2013): 145–48. http://dx.doi.org/10.3846/20296991.2013.859779.
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Under study reservoir oilfield is located south-west of Iran. This field is comprised of naturally fractured Asmari and Bangestan formation. Reservoir management and characteristic evaluation of this field requires good knowledge of reservoir rock and fluid properties. One of main methods to get such information is using known parameter and estimates this property in unknown area of reservoir by geostatistics and kriging method. In this research used the porosity parameter data from 36 oil wells that taken by well logging to estimate porosity parameter in unknown part of reservoir by geostatistics and kriging method. The porosity parameter had normal distribution. After surveyed the distribution of data varioghraphy was done and strength of structure was proved and kriging parameters including characteristic of search ellipse determined for estimation. Then porosity parameter was estimated with the use of geostatistical method in reservoir.
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Ren, Lei, Nanyang Chu, Zhan Hu, and Michael Hartnett. "Investigations into Synoptic Spatiotemporal Characteristics of Coastal Upper Ocean Circulation Using High Frequency Radar Data and Model Output." Remote Sensing 12, no. 17 (September 1, 2020): 2841. http://dx.doi.org/10.3390/rs12172841.
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Numerical models and remote sensing observation systems such as radars are useful for providing information on surface flows for coastal areas. Evaluation of their performance and extracting synoptic characteristics are challenging and important tasks. This research aims to investigate synoptic characteristics of surface flow fields through undertaking a detailed analysis of model results and high frequency radar (HFR) data using self-organizing map (SOM) and empirical orthogonal function (EOF) analysis. A dataset of surface flow fields over thirteen days from these two sources was used. A SOM topology map of size 4 × 3 was developed to explore spatial patterns of surface flows. Additionally, comparisons of surface flow patterns between SOM and EOF analysis were carried out. Results illustrate that both SOM and EOF analysis methods are valuable tools for extracting characteristic surface current patterns. Comparisons indicated that the SOM technique displays synoptic characteristics of surface flow fields in a more detailed way than EOF analysis. Extracted synoptic surface current patterns are useful in a variety of applications, such as oil spill treatment and search and rescue. This research provides an approach to using powerful tools to diagnose ocean processes from different aspects. Moreover, it is of great significance to assess SOM as a potential forecasting tool for coastal surface currents.
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Burmin, V. Yu, and A. G. Fat’yanov. "Analytical modeling of wave fields at extremely long distances and experimental research of water waves." Izvestiya, Physics of the Solid Earth 45, no. 4 (April 2009): 313–25. http://dx.doi.org/10.1134/s1069351309040041.
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Ramon, Jaume, Llorenç Lledó, Núria Pérez-Zanón, Albert Soret, and Francisco J. Doblas-Reyes. "The Tall Tower Dataset: a unique initiative to boost wind energy research." Earth System Science Data 12, no. 1 (February 18, 2020): 429–39. http://dx.doi.org/10.5194/essd-12-429-2020.
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Abstract. A dataset containing quality-controlled wind observations from 222 tall towers has been created. Wind speed and wind direction measurements covering the 1984–2017 period have been collected from existing tall towers around the world in an effort to boost the utilization of these non-standard atmospheric datasets, especially within the wind energy and research fields. Observations taken at several heights greater than 10 m above ground level have been retrieved from various sparse datasets and compiled in a unique collection with a common format, access, documentation and quality control. For the last, a total of 18 quality control checks have been considered to ensure the high quality of the wind records. Non-quality-controlled temperature, relative humidity and barometric pressure data from the towers have also been obtained and included in the dataset. The Tall Tower Dataset (Ramon and Lledó, 2019a) is published in the repository EUDAT and made available at https://doi.org/10.23728/b2share.136ecdeee31a45a7906a773095656ddb.
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Ren, Tianwei, Zhe Liu, Lin Zhang, Diyou Liu, Xiaojie Xi, Yanghui Kang, Yuanyuan Zhao, Chao Zhang, Shaoming Li, and Xiaodong Zhang. "Early Identification of Seed Maize and Common Maize Production Fields Using Sentinel-2 Images." Remote Sensing 12, no. 13 (July 3, 2020): 2140. http://dx.doi.org/10.3390/rs12132140.
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Accurate and timely access to the production area of crop seeds allows the seed market and secure seed supply to be monitored. Seed maize and common maize production fields typically share similar phenological development profiles with differences in the planting patterns, which makes it challenging to separate these fields from decametric-resolution satellite images. In this research, we proposed a method to identify seed maize production fields as early as possible in the growing season using a time series of remote sensing images in the Liangzhou district of Gansu province, China. We collected Sentinel-2 and GaoFen-1 (GF-1) images captured from March to September. The feature space for classification consists of four original bands, namely red, green, blue, and near-infrared (nir), and eight vegetation indexes. We analyzed the timeliness of seed maize identification using Sentinel-2 time series of different time spans and identified the earliest time frame for reasonable classification accuracy. Then, the earliest time series that met the requirements of regulatory accuracy were compared and analyzed. Four machine/deep learning algorithms were tested, including K-nearest neighbor (KNN), support vector classification (SVC), random forest (RF), and long short-term memory (LSTM). The results showed that using Sentinel-2 images from March to June, the RF and LSTM algorithms achieve over 88% accuracy, with the LSTM performing the best (90%). In contrast, the accuracy of KNN and SVC was between 82% and 86%. At the end of June, seed maize mapping can be carried out in the experimental area, and the precision can meet the basic requirements of monitoring for the seed industry. The classification using GF-1 images were less accurate and reliable; the accuracy was 85% using images from March to June. To achieve near real-time identification of seed maize fields early in the growing season, we adopted an automated sample generation approach for the current season using only historical samples based on clustering analysis. The classification accuracy using new samples extracted from historical mapping reached 74% by the end of the season (September) and 63% by the end of July. This research provides important insights into the classification of crop fields cultivated with the same crop but different planting patterns using remote sensing images. The approach proposed by this study enables near-real time identification of seed maize production fields within the growing season, which could effectively support large-scale monitoring of the seed supply industry.
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Morée, Anne L., and Jörg Schwinger. "A Last Glacial Maximum forcing dataset for ocean modelling." Earth System Science Data 12, no. 4 (November 20, 2020): 2971–85. http://dx.doi.org/10.5194/essd-12-2971-2020.
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Abstract. Model simulations of the Last Glacial Maximum (LGM; ∼ 21 000 years before present) can aid the interpretation of proxy records, can help to gain an improved mechanistic understanding of the LGM climate system, and are valuable for the evaluation of model performance in a different climate state. Ocean-ice only model configurations forced by prescribed atmospheric data (referred to as “forced ocean models”) drastically reduce the computational cost of palaeoclimate modelling compared to fully coupled model frameworks. While feedbacks between the atmosphere and ocean and sea-ice compartments of the Earth system are not present in such model configurations, many scientific questions can be addressed with models of this type. Our dataset supports simulations of the LGM in a forced ocean model set-up while still taking advantage of the complexity of fully coupled model set-ups. The data presented here are derived from fully coupled palaeoclimate simulations of the Palaeoclimate Modelling Intercomparison Project phase 3 (PMIP3). The data are publicly accessible at the National Infrastructure for Research Data (NIRD) Research Data Archive at https://doi.org/10.11582/2020.00052 (Morée and Schwinger, 2020). They consist of 2-D anomaly forcing fields suitable for use in ocean models that employ a bulk forcing approach and are optimized for use with CORE forcing fields. The data include specific humidity, downwelling long-wave and short-wave radiation, precipitation, wind (v and u components), temperature, and sea surface salinity (SSS). All fields are provided as climatological mean anomalies between LGM and pre-industrial (PI) simulations. These anomaly data can therefore be added to any pre-industrial ocean forcing dataset in order to obtain forcing fields representative of LGM conditions as simulated by PMIP3 models. Furthermore, the dataset can be easily updated to reflect results from upcoming and future palaeo-model intercomparison activities.
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Urrutia-Fucugauchi, Jaime, and Ligia Pérez-Cruz. "Planetary Sciences, Geodynamics, Impacts, Mass Extinctions, and Evolution: Developments and Interconnections." International Journal of Geophysics 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/4703168.
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Research frontiers in geophysics are being expanded, with development of new fields resulting from technological advances such as the Earth observation satellite network, global positioning system, high pressure-temperature physics, tomographic methods, and big data computing. Planetary missions and enhanced exoplanets detection capabilities, with discovery of a wide range of exoplanets and multiple systems, have renewed attention to models of planetary system formation and planet’s characteristics, Earth’s interior, and geodynamics, highlighting the need to better understand the Earth system, processes, and spatio-temporal scales. Here we review the emerging interconnections resulting from advances in planetary sciences, geodynamics, high pressure-temperature physics, meteorite impacts, and mass extinctions.
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Williamson, Marie-Claude, Catherine L. Johnson, and Paul J. Sylvester. "Introduction to Special Issue ofCanadian Journal of Earth Sciences: Canadian contributions to planetary geoscience." Canadian Journal of Earth Sciences 50, no. 1 (January 2013): 1–3. http://dx.doi.org/10.1139/cjes-2012-0164.
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The first Special Issue published by the Canadian Journal of Earth Sciences in the field of planetary sciences consists of a collection of nine papers on astromaterials, planetary geology, and Earth-based analogues. We describe the milestones that led to the development of the planetary geology and geophysics (PG&G) community in Canada over the past 5 years, which culminated in record-breaking attendance at a special session of the 2011 GAC–MAC–SEG–SGA Joint Annual Meeting held in Ottawa. The idea of a Special Issue was met with enthusiasm by delegates from coast to coast. By connecting the fields of earth and planetary sciences, the Canadian Journal of Earth Sciences pioneers a new vision for geoscience that expands the options available to Canadians who wish to publish their research at home.
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Stoffel, M., and M. Bollschweiler. "Tree-ring analysis in natural hazards research – an overview." Natural Hazards and Earth System Sciences 8, no. 2 (March 11, 2008): 187–202. http://dx.doi.org/10.5194/nhess-8-187-2008.
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Abstract. The understanding of geomorphic processes and knowledge of past events are important tasks for the assessment of natural hazards. Tree rings have on varied occasions proved to be a reliable tool for the acquisition of data on past events. In this review paper, we provide an overview on the use of tree rings in natural hazards research, starting with a description of the different types of disturbances by geomorphic processes and the resulting growth reactions. Thereafter, a summary is presented on the different methods commonly used for the analysis and interpretation of reactions in affected trees. We illustrate selected results from dendrogeomorphological investigations of geomorphic processes with an emphasis on fluvial (e.g., flooding, debris flows) and mass-movement processes (e.g., landslides, snow avalanche), where lots of data have been generated over the past few decades. We also present results from rockfall and permafrost studies, where data are much scarcer, albeit data from tree-ring studies have proved to be of great value in these fields as well. Most studies using tree rings have focused on alpine environments in Europe and North America, whereas other parts of the world have been widely neglected by dendrogeomorphologists so far. We therefore challenge researchers to focus on other regions with distinct climates as well, to look on less frequently studied processes as well and to broaden and improve approaches and methods commonly used in tree-ring research so as to allow a better understanding of geomorphic processes, natural hazards and risk.
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Luo, Bingkun, and Peter J. Minnett. "Evaluation of the ERA5 Sea Surface Skin Temperature with Remotely-Sensed Shipborne Marine-Atmospheric Emitted Radiance Interferometer Data." Remote Sensing 12, no. 11 (June 9, 2020): 1873. http://dx.doi.org/10.3390/rs12111873.
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Sea surface temperature is very important in weather and ocean forecasting, and studying the ocean, atmosphere and climate system. Measuring the sea surface skin temperature (SSTskin) with infrared radiometers onboard earth observation satellites and shipboard instruments is a mature subject spanning several decades. Reanalysis model output SSTskin, such as from the newly released ERA5, is very widely used and has been applied for monitoring climate change, weather prediction research, and other commercial applications. The ERA5 output SSTskin data must be rigorously evaluated to meet the stringent accuracy requirements for climate research. This study aims to estimate the accuracy of the ERA5 SSTskin fields and provide an associated error estimate by using measurements from accurate shipboard infrared radiometers: the Marine-Atmosphere Emitted Radiance Interferometers (M-AERIs). Overall, the ERA5 SSTskin has high correlation with ship-based radiometric measurements, with an average difference of~0.2 K with a Pearson correlation coefficient (R) of 0.993. Parts of the discrepancies are related to dust aerosols and variability in air-sea temperature differences. The downward radiative flux due to dust aerosols leads to significant SSTskin differences for ERA5. The SSTskin differences are greater with the large, positive air–sea temperature differences. This study provides suggestions for the applicability of ERA5 SSTskin fields in a selection of research applications.
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Cooper, Hollie M., Emma Bennett, James Blake, Eleanor Blyth, David Boorman, Elizabeth Cooper, Jonathan Evans, et al. "COSMOS-UK: national soil moisture and hydrometeorology data for environmental science research." Earth System Science Data 13, no. 4 (April 28, 2021): 1737–57. http://dx.doi.org/10.5194/essd-13-1737-2021.
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Abstract. The COSMOS-UK observation network has been providing field-scale soil moisture and hydrometeorological measurements across the UK since 2013. At the time of publication a total of 51 COSMOS-UK sites have been established, each delivering high-temporal resolution data in near-real time. Each site utilizes a cosmic-ray neutron sensor, which counts epithermal neutrons at the land surface. These measurements are used to derive field-scale near-surface soil water content, which can provide unique insight for science, industry, and agriculture by filling a scale gap between localized point soil moisture and large-scale satellite soil moisture datasets. Additional soil physics and meteorological measurements are made by the COSMOS-UK network including precipitation, air temperature, relative humidity, barometric pressure, soil heat flux, wind speed and direction, and components of incoming and outgoing radiation. These near-real-time observational data can be used to improve the performance of hydrological models, validate remote sensing products, improve hydro-meteorological forecasting, and underpin applications across a range of other scientific fields. The most recent version of the COSMOS-UK dataset is publically available at https://doi.org/10.5285/b5c190e4-e35d-40ea-8fbe-598da03a1185 (Stanley et al., 2021).
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Bassier, Maarten, and Maarten Vergauwen. "Clustering of Wall Geometry from Unstructured Point Clouds Using Conditional Random Fields." Remote Sensing 11, no. 13 (July 4, 2019): 1586. http://dx.doi.org/10.3390/rs11131586.
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The automated reconstruction of Building Information Modeling (BIM) objects from point cloud data is still subject of ongoing research. A vital step in the process is identifying the observations for each wall object. Given a set of segmented and classified point clouds, the labeled segments should be clustered according to their respective objects. The current processes to perform this task are sensitive to noise, occlusions, and the associativity between faces of neighboring objects. The proper retrieval of the observed geometry is especially important for wall geometry as it forms the basis for further BIM reconstruction. In this work, a method is presented to automatically group wall segments derived from point clouds according to the proper walls of a building. More specifically, a Conditional Random Field is employed that evaluates the context of each wall segment in order to determine which wall it belongs to. First, a set of classified planar primitives is obtained through algorithms developed in prior work. Next, both local and contextual features are extracted based on the nearest neighbors and a number of seeds that are heuristically determined. The final wall clusters are then computed by decoding the graph. The method is tested on our own data as well as the 2D-3D-Semantics (2D-3D-S) benchmark data of Stanford. Compared to a conventional region growing method, the proposed method reduces the rate of false positives, resulting in better wall clusters. Overall, the method computes a more balanced clustering of the observations. A key advantage of the proposed method is its capability to deal with wall geometry in complex configurations in multi-storey buildings opposed to the presented methods in current literature.
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Calderoni, Gilberto, and Vincenzo Petrone. "Department of Earth Sciences at the University of Rome Radiocarbon Dates I." Radiocarbon 34, no. 1 (1992): 105–13. http://dx.doi.org/10.1017/s0033822200013448.
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We report here, in part, dates measured on samples from Italy since the construction of a new 14C lab in 1990 for research in the fields of geology, paleomorphology and the biogeochemical cycle of carbon. We use liquid scintillation counting (LSC), following sample conversion to benzene through the four classical chemical steps: 1) combustion or hydrolysis to CO2; 2) production of Li2C2; 3) hydrolysis to C2H2; 4) trimerization of acetylene to C6H6 with specific catalysts. The vacuum line for benzene synthesis has been designed following a comparative review of the literature (Tamers 1960; Noakes et al. 1963; Scharpenseel & Pietig 1970; Harkness & Wilson 1973; Polach, Gower & Fraser 1972; Gupta & Polach 1985), and the valuable suggestions of many colleagues from well-established labs abroad. The compact vacuum line is mostly modular with “O”-ring-joined components, and is equipped with greaseless stopcocks. We use commercial two-stage rotary pumps, pressure transducers and gauges; an electrovalve coupled with a pressure control unit supplies the purified oxygen for sample combustion while holding constant, just higher than 1 atm, the gas pressure inside the combustion tube.
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Medić, Tomislav, Heiner Kuhlmann, and Christoph Holst. "Sensitivity Analysis and Minimal Measurement Geometry for the Target-Based Calibration of High-End Panoramic Terrestrial Laser Scanners." Remote Sensing 11, no. 13 (June 27, 2019): 1519. http://dx.doi.org/10.3390/rs11131519.
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Target-based calibration is the most widely used calibration procedure for terrestrial laser scanners. Nevertheless, the current implementations of this procedure are suboptimal due to the high complexity of their calibration fields. Therefore, designing calibration fields, by selecting optimal target locations with respect to the instrument, is a pending research question. Answering this question would lead to a more efficient and user-friendly calibration, as well as improved calibration results. Herein, we conduct a detailed analysis of the most sensitive target-to-instrument measurement configuration to estimate individual calibration parameters. Based on this analysis, we derive a minimal measurement geometry, sensitive to all mechanical misalignments, relevant for high-end panoramic terrestrial laser scanners. We support our sensitivity analysis by a simulation and empirical experiments followed by a discussion about the advantages and shortcomings of the proposed minimal measurement geometry.
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Förster, K., G. Meon, and U. Strasser. "Modelling of snow processes in catchment hydrology by means of downscaled WRF meteorological data fields." Hydrology and Earth System Sciences Discussions 11, no. 4 (April 11, 2014): 4063–102. http://dx.doi.org/10.5194/hessd-11-4063-2014.
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Abstract. Detailed physically based snowmelt models require a complete set of meteorological forcing data at the model's scale. Besides precipitation and temperature, time series of humidity, wind speed, and radiation have to be provided. The availability of these time series is in many cases restricted to a few meteorological stations and consequently, snowmelt modelling is often highly uncertain. To overcome this dilemma, the suitability of downscaled atmospheric analysis data for physically based snowmelt simulations in hydrological modelling is studied. We used the Weather Research and Forecast model (WRF) to derive spatial and temporal fields of meteorological surface variables as boundary conditions for four different snowmelt models. The simulations were carried out at the point scale and at the catchment scale for the Sieber catchment (44.4 km2), Harz Mountains, Germany. For the latter, all snowmelt models were integrated into the hydrological modelling system PANTA RHEI. All models performed well at both scales. In conclusion, the presented approach is suitable to derive reliable estimates of snowpack and snowmelt processes as part of water balance and flood simulations for catchments exposed to snow.
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Adi Putra, Hangga Novian, and Wahyudi Wahyudi. "The Estimation of Subsurface Structure within Geothermal Manifestation Area as an Outflow Zone Using Geoelectrical Resistivity Method in Tegal, Jawa Tengah." GeoEco 7, no. 1 (January 31, 2021): 1. http://dx.doi.org/10.20961/ge.v7i1.42392.
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<p class="TesisTextOneHalfSpace"><em>Indonesia is one of the country having a lot of geothermal fields potentially used as a source of energy. For example, Java island is noted to have almost 57 geothermal fields. One of those geothermal fields which is rarely studied is Guci geothermal field. Hence, there was conducted a research to investigate the subsurface image and geothermal system in Guci geothermal field based on resistivity data. </em><em>The research in Guci geothermal field was carried out using geoelectrical method. Resistivity geoelectrical research used two configurations, namely dipole-dipole and schlumberger. Data acquisitions for dipole-dipole configuration was done in two lines, 500 metres spread for each line. Whereas the acquisitions for schlumberger configuration was done in four points, 200-250 metres spread for each point. </em><em>Research result showed that the area of geothermal manifestation in Guci consist of top soil layer, sandstone, andesite, and a fluids-containing layer. A fluids-containing layer is estimated to be related to geothermal manifestation in Guci and is a fault zone. Fault is estimated to be a normal fault and lies in 20 metres depth. Fault within geothermal manifestation area in Guci has a role as the pathway of hot-fluid out to the surface which forms a manifestation.</em></p>
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Jiang, Xiaowei, Jun Li, Zhenglong Li, Yunheng Xue, Di Di, Pei Wang, and Jinlong Li. "Evaluation of Environmental Moisture from NWP Models with Measurements from Advanced Geostationary Satellite Imager—A Case Study." Remote Sensing 12, no. 4 (February 18, 2020): 670. http://dx.doi.org/10.3390/rs12040670.
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The distribution of tropospheric moisture in the environment is highly associated with storm development. Therefore, it is important to evaluate the uncertainty of moisture fields from numerical weather prediction (NWP) models for better understanding and enhancing storm prediction. With water vapor absorption band radiance measurements from the advanced imagers onboard the new generation of geostationary weather satellites, it is possible to quantitatively evaluate the environmental moisture fields from NWP models. Three NWP models—Global Forecast System (GFS), Unified Model (UM), Weather Research and Forecasting (WRF)—are evaluated with brightness temperature (BT) measurements from the three moisture channels of Advanced Himawari Imager (AHI) onboard the Himawari-8 satellite for Typhoon Linfa (2015) case. It is found that the three NWP models have similar performance for lower tropospheric moisture, and GFS has a smaller bias for middle tropospheric moisture. Besides, there is a close relationship between moisture forecasts in the environment and the tropical cyclone (TC) track forecasts in GFS, while regional WRF does not show this pattern. When the infrared and microwave sounder radiance measurements from polar orbit satellite are assimilated in regional WRF, it is clearly shown that the environment moisture fields are improved compared with that with only conventional data are assimilated.
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Oktar, Osman, and Hediye Erdoğan. "Research of behaviors of continuous GNSS station by signal analysis methods." Earth Sciences Research Journal 22, no. 1 (January 1, 2018): 19–27. http://dx.doi.org/10.15446/esrj.v22n1.62552.
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Continuously Operating Reference Station (CORS) networks consisting of multiple GNSS systems have been set up and operating in many developed countries. In Turkey, CORS-TR has been operating. The aim of CORS-TR is a fast, correct, and reliable collection of all kinds of geographic data, thus, speeding up the activities of cadastre, assuring organized urbanization, constituting the spatial infrastructure for relevant works of e-government, and monitoring plate tectonics. Therefore, in this paper, we investigated 788 days of linear and periodic of AKHR, BEYS, CIHA, KAMN, YUNA, AKSI and KNYA CORS-TR stations by linear trend analysis and Wavelet Transform in located in the Central Anatolia Region of Turkey. As a result of trend analyses of time series, it was determined that except a single station (KAMN), other stations were moving in the Southwest direction (17.78 mm/year). This finding is consistent with the region’s tectonic plate movements. In the periodical analyses, stations’ daily, monthly, seasonal, annual and even biennial movements resulting from atmospheric and hydrologic loading, climatic and other effects were revealed. Moreover, Detail (D) component, which protects the largest percentage of energy, was determined by calculating the energy spectrum. Energies of detail components are similar in horizontal, and especially D7-D8 have the highest energy. However, the components obtained the maximum energy was varied in Up coordinate time series. These results indicate that stations of CORS-TR network located in Central Anatolia were rather stable and able to be providing reliable, accurate and continuous data for national and international studies to be conducted in many fields.
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Kvíderová, Jana. "Research on cryosestic communities in Svalbard: the snow algae of temporary snowfields in Petuniabukta, Central Svalbard." Czech Polar Reports 2, no. 1 (January 1, 2012): 8–19. http://dx.doi.org/10.5817/cpr2012-1-2.
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Although the observations of the colored snow in Svalbard are dated from 17th century, the research in cryosestic algae during last 50 years was focused to NW part of Svalbard, Hornsund and Sveagruva areas. No observations have been reported for the Central or East Svalbard yet, with exception of Longyearbyen and Sveagruva areas. In Petuniabukta, two types of possible cryoseston habitats were recognized: 1) temporal snow fields that melt-away in summer completely, and 2) perennial glacier surfaces. During summer seasons 2009 - 2011, ten temporary snow field samples were sampled in the Petuniabukta area. The cryosestic communities did not cause visible snow coloration, however the presence of snow algae was revealed by light microscope. In samples, zygospores of Chlamydomonas cf. nivalis, were dominant. Other found species included Chlamydomonas nivalis, Chloromonas nivalis, Cryodactylon glaciale, and cf. Chainomonas sp. No motile stages of snow algae were observed. Due to low cell concentration and association of the cells with dust grains, wind transport of snow algae to the snow fields seems to be more possible than presence of a stable cryosestic community growing in situ.
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Shtohryn, Liudmyla. "GEODYNAMICS." GEODYNAMICS 1(30)2021, no. 1(30) (June 29, 2021): 65–77. http://dx.doi.org/10.23939/jgd2021.01.065.
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Purpose. The aim of the research presented in this article is to analyze the features of the reflection of the damage to the territory of the Transcarpathian region by landslide processes based on the anomalies in the magnetic and gravitational fields, taking into account tectonic zoning. The study is an important stage in predicting the landslide processes and it is aimed at reducing their negative effects on the environment. The relevance of the research is due to the growing intensification of landslides in the Carpathian region of Ukraine. Methodology. The development of landslides in each structural-tectonic zone is associated with its tectonic structure, and therefore these processes can have different intensity, dynamics, tendencies for further development and distribution area. Lithological-facies composition and bedding conditions of rocks form the physical and mechanical properties of rocks, determining the rate and mechanism of the development of landslides. The spatial confinedness of landslide processes in the fault zones is reflected in the gravitational and magnetic fields. Results. With the help of GIS MapInfo tools, a number of landslides in each tectonic zone, anomalies in the gravitational and magnetic fields, areas affected by landslides, the distance to the fault zones were calculated. The important result of the research is to prove a direct correlation between the spatial distribution of landslides and fault zones, tectonic structure, the lithological composition of rocks, which are reflected in gravimagnetic anomalies. Scientific novelty. The peculiarities of the reflection of the tectonic structure, zones of decompression, fragmentation of rocks and lithological composition in gravimagnetic fields on a regional scale are examined, and their association with landslide processes is evaluated for the first time. Practical significance. The theoretical substantiation of the peculiarities of the behaviour of gravimagnetic fields in the zones of distribution of landslide processes makes it possible to assess the natural conditions for the formation and development of landslides in a given region. The connection between the impact of the fault zones on landslide processes by their reflection in gravimagnetic fields is established, which can be used in the future for spatial forecasting of the development of landslides in territories with related structural-tectonic conditions.
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Herzfeld, Ute C., Sheldon Drobot, Wanli Wu, Charles Fowler, and James Maslanik. "Spatiotemporal Climate Model Validation—Case Studies for MM5 over Northwestern Canada and Alaska." Earth Interactions 11, no. 20 (December 1, 2007): 1–23. http://dx.doi.org/10.1175/ei208.1.
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Abstract The Western Arctic Linkage Experiment (WALE) is aimed at understanding the role of high-latitude terrestrial ecosystems in the response of the Arctic system to global change through collection and comparison of climate datasets and model results. In this paper, a spatiotemporal approach is taken to compare and validate model results from the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) with commonly used analysis and reanalysis datasets for monthly averages of temperature and precipitation in 1992–2000 and for a study area at 55°–65°N, 160°–110°W in northwestern Canada and Alaska. Objectives include a quantitative assessment of similarity between datasets and climate model fields, and identification of geographic areas and seasons that are problematic in modeling, with potential causes that may aid in model improvement. These are achieved by application of algebraic similarity mapping, a simple yet effective method for synoptic analysis of many (here, 45) different spatial datasets, maps, and models. Results indicate a dependence of model–data similarity on seasonality, on climate variable, and on geographic location. In summary, 1) similarity of data and models is better for temperature than for precipitation; and 2) modeling of summer precipitation fields, and to a lesser extent, temperature fields, appears more problematic than that of winter fields. The geographic distribution of areas with best and worst agreement shifts throughout the year, with generally better agreement between maps and models in the northeastern and northern inland areas than in topographically complex and near-coastal areas. The study contributes to an understanding of the geographic complexity of the Arctic system and modeling its diverse climate.
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Li, Xingrong, Chenghai Yang, Hongri Zhang, Panpan Wang, Jia Tang, Yanqin Tian, and Qing Zhang. "Identification of Abandoned Jujube Fields Using Multi-Temporal High-Resolution Imagery and Machine Learning." Remote Sensing 13, no. 4 (February 22, 2021): 801. http://dx.doi.org/10.3390/rs13040801.
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The jujube industry plays a very important role in the agricultural industrial structure of Xinjiang, China. In recent years, the abandonment of jujube fields has gradually emerged. It is critical to inventory the abandoned land soon after it is generated to adjust agricultural production better and prevent the negative impacts from the abandonment (such as outbreaks of diseases, insect pests, and fires). High-resolution multi-temporal satellite remote sensing images can be used to identify subtle differences among crops and provide a good tool for solving this problem. In this research, both field-based and pixel-based classification approaches using field boundaries were used to estimate the percentage of abandoned jujube fields with multi-temporal high spatial resolution satellite images (Gaofen-1 and Gaofen-6) and the Random Forest algorithm. The results showed that both approaches produced good classification results and similar distributions of abandoned fields. The overall accuracy was 91.1% for the field-based classification and 90.0% for the pixel-based classification, and the Kappa was 0.866 and 0.848 for the respective classifications. The areas of abandoned land detected in the field-based and pixel-based classification maps were 806.09 ha and 828.21 ha, respectively, accounting for 8.97% and 9.11% of the study area. In addition, feature importance evaluations of the two approaches showed that the overall importance of texture features was higher than that of vegetation indices and that 31 October and 10 November were important dates for abandoned land detection. The methodology proposed in this study will be useful for identifying abandoned jujube fields and have the potential for large-scale application.
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Malaurie, Jean. "J.-B. Charcot; father of French polar research." Polar Record 25, no. 154 (July 1989): 191–96. http://dx.doi.org/10.1017/s0032247400010780.
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AbstractBorn in 1867 and trained as a doctor, Jean-Baptiste Charcot gave up a fashionable medical practice to become, in his mid-thirties, France's leading polar explorer. His two major expeditions to the peninsular sector of Antarctica and the Bellingshausen Sea (1903–05, 1908–10) resulted in many new discoveries of land and established his reputation as a leader in the fields of scientific oceanography, research and survey. After service in World War I he continued polar work with a series of ten summer expeditions to the Arctic (1926–36), in which many young explorers were trained. Lost with his ship Pourquoi Pas? in a storm off Iceland in 1936, Charcot is remembered for qualities of leadership and scientific integrity which inspire the current generation of French polar scientists.
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Gousheva, M., D. Danov, P. Hristov, and M. Matova. "Quasi-static electric fields phenomena in the ionosphere associated with pre- and post earthquake effects." Natural Hazards and Earth System Sciences 8, no. 1 (February 21, 2008): 101–7. http://dx.doi.org/10.5194/nhess-8-101-2008.
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Abstract. To prove a direct relationship between the quasi-static electric field disturbances and seismic activity is a difficult, but actual task of the modern ionosphere physics. This paper presents new results on the processing and analysis of the quasi-static electric field in the upper ionosphere (h=800–900 km) observed from the satellite INTERCOSMOS-BULGARIA-1300 over earthquakes' source regions (seismic data of World Data Center, Denver, Colorado, USA). Present research focuses on three main areas (i) development of methodology of satellite and seismic data selecting, (ii) data processing and observations of the quasi-static electric field (iii) study and accumulation of statistics of possible connection between anomalous vertical electric fields penetrating from the earthquake zone into the ionosphere, and seismic activity. The most appropriate data (for satellite orbits above sources of forthcoming or just happened seismic events) have been selected from more than 250 investigated cases.The increase of about 5-10-15 mV/m in the vertical component of the quasi-static electric field observed by INTERCOSMOS-BULGARIA-1300 during seismic activity over Southern Ocean, Greenland Sea, South-Weat Pacific Ocean, Indian Ocean, Central America, South-East Pacific Ocean, Malay Archipelago regions are presented. These anomalies, as phenomena accompanying the seismogenic process, can be considered eventually as possible pre-, co- (coeval to) and post-earthquake effects in the ionosphere.
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Zhang, Lin, Zhe Liu, Tianwei Ren, Diyou Liu, Zhe Ma, Liang Tong, Chao Zhang, Tianying Zhou, Xiaodong Zhang, and Shaoming Li. "Identification of Seed Maize Fields With High Spatial Resolution and Multiple Spectral Remote Sensing Using Random Forest Classifier." Remote Sensing 12, no. 3 (January 22, 2020): 362. http://dx.doi.org/10.3390/rs12030362.
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Seed maize and common maize plots have different planting patterns and variety types. Identification of seed maize is the basis for seed maize growth monitoring, seed quality and common maize seed supply. In this paper, a random forest (RF) classifier is used to develop an approach for seed maize fields’ identification, using the time series vegetation indexes (VIs) calculated from multispectral data acquired from Landsat 8 and Gaofen 1 satellite (GF-1), field sample data, and texture features of Gaofen 2 satellite (GF-2) panchromatic data. Huocheng and Hutubi County in the Xinjiang Uygur Autonomous Region of China were chosen as study area. The results show that RF performs well with the combination of six VIs (normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), triangle vegetation index (TVI), ratio vegetation index (RVI), normalized difference water index (NDWI) and difference vegetation index (DVI)) and texture features based on a grey-level co-occurrence matrix. The classification based on “spectrum + texture” information has higher overall, user and producer accuracies than that of spectral information alone. Using the “spectrum + texture” method, the overall accuracy of classification in Huocheng County is 95.90%, the Kappa coefficient is 0.92, and the producer accuracy for seed maize fields is 93.91%. The overall accuracy of the classification in Hutubi County is 97.79%, the Kappa coefficient is 0.95, and the producer accuracy for seed maize fields is 97.65%. Therefore, RF classifier inputted with high-resolution remote-sensing image features can distinguish two kinds of planting patterns (seed and common) and varieties types (inbred and hybrid) of maize and can be used to identify and map a wide range of seed maize fields. However, this method requires a large amount of sample data, so how to effectively use and improve it in areas lacking samples needs further research.
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Stuchlík, Radim, Zdeněk Stachoň, Kamil Láska, and Petr Kubíček. "Unmanned Aerial Vehicle – Efficient mapping tool available for recent research in polar regions." Czech Polar Reports 5, no. 2 (June 1, 2015): 210–21. http://dx.doi.org/10.5817/cpr2015-2-18.
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Unmanned Aerial Vehicles (UAV) have technical capabilities to extended usage in various fields ofscience. The existing UAVs are to be relatively easily accessible in the near future. It is possible to equip them with different sensors but there are still some usage limitations. This paper focuses ondemonstrating UAVs usage for research in polar regions. The research in polar regions is very specific and, due to harsh climate, limits the field work with UAVs. The options and limitations are presented in a case study performed in the Nordenskiöldbreen area, Svalbard Archipelago. In the end some derived products suitable for further analysis are presented.
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Yang, Chengsheng, Bingquan Han, Chaoying Zhao, Jiantao Du, Dongxiao Zhang, and Sainan Zhu. "Co- and post-seismic Deformation Mechanisms of the MW 7.3 Iran Earthquake (2017) Revealed by Sentinel-1 InSAR Observations." Remote Sensing 11, no. 4 (February 18, 2019): 418. http://dx.doi.org/10.3390/rs11040418.
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The extraction of high-accuracy co- and post-seismic deformation fields and inversions of seismic slip distributions is significant in the comprehension of seismogenic mechanisms. On 12 November 2017, a MW 7.3 earthquake occurred on the border between Iran and Iraq. To construct the co-seismic deformation field, Sentinel-1A synthetic aperture radar (SAR) images from three tracks were used. Based on a prior knowledge, least-squares iterative approximation was employed to construct the three-dimensional (3D) co-seismic deformation field. to derive a time series of 2D post-seismic deformation, the multidimensional small baseline subset (MSBAS) technique was use. Co-seismic deformation fields were asymmetric; the maximum relative displacement was nearly 90cm in the radar line-of-sight between two centers of co-seismic deformation. The 3D co-seismic deformation field showed southwestward horizontal motion and continuous subsidence-to-uplift variation from northeast to southwest. The two-dimensional (2D) post-seismic deformation time series showed a gradual decaying trend and good correspondence with the aftershock distribution. The main mechanism of post-seismic deformation was an afterslip of the post-seismic faults. We used the elastic half-space model to invert co-seismic deformation fields and obtain source parameters of the slip model. The maximum and average slips were 2.5 and 0.72 m, respectively. The average slip angle was 126.38° and the moment magnitude was MW 7.34. The results of this study will contribute to research on regional tectonic activities.
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Babadzhanov, Pulat B. "Astronomical Research and Education in Tajikistan." Transactions of the International Astronomical Union 24, no. 3 (2001): 187–96. http://dx.doi.org/10.1017/s0251107x00000742.
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AbstractAstronomical researches in Tajikistan are carried out by the Institute of Astrophysics, Tajik Academy of Sciences. The main scientific fields of investigation are physics and dynamics of asteroids, comets and meteors, variable stars and observations of artificial Earth satellites. The Institute has three observational stations: the Gissar observatory (at an altitude 730 m above sea-level) with photographic fireball and meteor patrols, a 70-cm reflector, a 40-cm Zeiss astrograph, a high-precision astronomical telescope (D=1 m, F=0.75 m), etc.; the Sanglokh observatory (at an altitude 2300 m above sea-level) with a Ritchey-Chretien 1-m telescope and 0.6-m reflector by Carl Zeiss; the Pamir observatory (at an altitude 4350 m above sea-level) with a 70-cm reflector. In 1999 the Department of Astronomy was restored in the Tajik State National University and the first students were admitted to this university for the astronomical profession.
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Goh, Y. K., A. R. Holt, and P. P. Alberoni. "Doppler radar wind field retrieval over the Po Valley." Natural Hazards and Earth System Sciences 6, no. 2 (May 4, 2006): 285–91. http://dx.doi.org/10.5194/nhess-6-285-2006.
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Abstract. Although methods of using multiple Doppler radars to study wind fields have long been proposed, and many research studies have been made, very few operational radar operators adopt methods which require the use of specific scanning strategies to allow the extraction of wind information. Here we report a collaborative study on dual-Doppler radars based on two Doppler radars in the Po valley, Italy. Unusually, the radars are only about 90 km apart, though operated by the same authority. The wind field syntheses are carried out on a 30 km by 30 km region where the two radars have overlapping scan coverage. An iterative method based on the linear wind model and the equation of mass continuity is used to construct the wind fields. The methodology has been validated by two different methods. The first method is to reconstruct the radial wind observed by each radar, and the second method is calculating and comparing the along-track component with that derived from the observations. Both two comparisons show good agreement with the original data.
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Nora Hardt, Judith. "Research Perspectives and Boundaries of Thought: Security, Peace, Conflict, and the Anthropocene." Revista de Estudios en Seguridad Internacional 7, no. 1 (June 21, 2021): 11–28. http://dx.doi.org/10.18847/1.13.3.
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The geological era of the Anthropocene is expected to trigger a paradigm shift across the natural and social sciences. Within International Relations (IR), the arrival of the planetary has generated various debates that range from questioning the very future of the discipline to proposals for how to fix IR. This article takes stock of different research perspectives from three disciplines, namely IR, Earth System Sciences and New Materialism/Posthumanism. With reference to these different perspectives, it examines the ways in which peace, conflict and security are related to the Anthropocene. This panoramic overview reveals also certain demarcations between the research approaches, disciplines and study fields, and aims to trigger future research on overcoming these boundaries of thought and push the research on Anthropocene thinking further.
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Bielecka and Jenerowicz. "Intellectual Structure of CORINE Land Cover Research Applications in Web of Science: A Europe-Wide Review." Remote Sensing 11, no. 17 (August 27, 2019): 2017. http://dx.doi.org/10.3390/rs11172017.
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The objective of this paper is to manifest the intellectual and cognitive structure of CORINE Land Cover (CLC) research applications. Data from the Web of Science (WoS) was used to delimit publication on CLC during the period from 1985 until 2019 (29th April), retrieving a total of 873 documents. Through author citations, the origins and the most influential papers were identified. The main lines of research were identified from word co-occurrences extracted from the titles, keywords, and abstracts of the papers. In the view of both structures, it can be concluded that CORINE land cover constitutes a relatively young set of scientific data, with a constant expansion and a strongly interdisciplinary structure. The development of this application is dependent on the knowledge of such research areas as geography, remote sensing, ecology, forestry, agriculture, engineering, optics, and/or computer science. We believe that this information could be very useful for CLC users, as it reflects a large-scale analysis of the research lines of CLC and illuminates how research has changed over time in diverse areas of applications. Moreover, this study is intended to offer a useful tool for the CLC scientific community, showcasing the main research lines and the most noteworthy papers. Finally, the methodology used in this study can be replicated in many other fields of science to explore its intellectual and cognitive structure.
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Lima, Silvio Felipe Barbosa. "PECEN Publications in the Field of Biological Sciences: Present and Future." Pesquisa e Ensino em Ciências Exatas e da Natureza 1, no. 2 (December 11, 2017): 84. http://dx.doi.org/10.29215/pecen.v1i2.445.
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Biological Sciences is the discipline that studies the most diverse aspects of microscopic and macroscopic life forms on earth. This vast field of studies enables biologists to follow numerous paths according to their professional interest.<br />Biological Sciences has made rapid advances in Biochemistry, Biophysics, Biotechnology, Botany, Cell Biology, Ecology, Ethnobiology, Evolutionary Biology, Genetics, Immunology, Mycology, Microbiology, Morphology, Parasitology, Physiology and Zoology. In some cases, the expansion of different fields of Biological Sciences is tied to the crisis of biodiversity and environmental problems, such as the extinction of species, the introduction of invasive exotic species, increasing habitat loss and degradation, the overexploitation of natural resources, pollution, diseases and human-induced climate change.<br />In 2017, Pesquisa e Ensino em Ciências Exatas e da Natureza/Research and Teaching in Exact and Natural Sciences (PECEN) received 28 manuscripts for evaluation and published 18 papers, all related to the field of Biological Sciences. An analysis of the papers published in year shows that the field of Zoology (branch of Biology that studies the animal kingdom) has been the flagship of publications with 7 papers so far. Among the contributions within Zoology published in PECEN are papers involving the following sub-fields of knowledge: (2) Morphology of Recent Groups; (4) Taxonomy of Recent Groups; and (3) “ecological interactions” – phenomenon and object of study also in the field of Ecology. In 2017, PECEN also published important contributions in the fields of Ecology (2), Environmental Sciences (1), Health and Biological Science (1), Mycology (2) and Science Teaching (2).<br />Contributions in the fields of biodiversity and science teaching will undoubtedly continue to play an important role in the scientific production of PECEN in both qualitative and quantitative terms. However, given the vast field of Biological Sciences, we expect a substantial increase in the number of publications on the most diverse subjects in 2018.<br />It is important to emphasize that PECEN is a multidisciplinary journal that receives contributions from diverse fields, such as Agrarian, Biomedical, Chemical, Earth, Environmental, Health and Exact and Natural Sciences. The fundamental mission is to strengthen multidisciplinary publications through scientific and theoretical-methodological studies as well as thematic literature reviews. Regardless of the number of submissions, the main factor for publication in PECEN is the importance and quality of the contributions.
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Chaudhuri, Ayan H., and Rui M. Ponte. "An Evaluation of Surface Atmospheric Changes over the Arctic Ocean for 2000–09 Using Recent Reanalyses." Earth Interactions 19, no. 2 (January 1, 2015): 1–18. http://dx.doi.org/10.1175/ei-d-14-0012.1.
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Abstract The authors examine five recent reanalysis products [NCEP Climate Forecast System Reanalysis (CFSR), Modern-Era Retrospective Analysis for Research and Applications (MERRA), Japanese 25-year Reanalysis Project (JRA-25), Interim ECMWF Re-Analysis (ERA-Interim), and Arctic System Reanalysis (ASR)] for 1) trends in near-surface radiation fluxes, air temperature, and humidity, which are important indicators of changes within the Arctic Ocean and also influence sea ice and ocean conditions, and 2) fidelity of these atmospheric fields and effects for an extreme event: namely, the 2007 ice retreat. An analysis of trends over the Arctic for the past decade (2000–09) shows that reanalysis solutions have large spreads, particularly for downwelling shortwave radiation. In many cases, the differences in significant trends between the five reanalysis products are comparable to the estimated trend within a particular product. These discrepancies make it difficult to establish a consensus on likely changes occurring in the Arctic solely based on results from reanalyses fields. Regarding the 2007 ice retreat event, comparisons with remotely sensed estimates of downwelling radiation observations against these reanalysis products present an ambiguity. Remotely sensed observations from a study cited herewith suggest a large increase in downwelling summertime shortwave radiation and decrease in downwelling summertime longwave radiation from 2006 and 2007. On the contrary, the reanalysis products show only small gains in summertime shortwave radiation, if any; however, all the products show increases in downwelling longwave radiation. Thus, agreement within reanalysis fields needs to be further checked against observations to assess possible biases common to all products.
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Li, Gang, and Jiafei Teng. "Research and Optimization of Gas Extraction by Crossing-Seam Boreholes from Floor Roadway." Geofluids 2021 (August 9, 2021): 1–10. http://dx.doi.org/10.1155/2021/7499012.
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Deep coal seams are characterized by large stress, high gas pressure, and low permeability. The gas disaster threatens the safe production of coal mine seriously. Gas extraction by crossing-seam boreholes from floor roadway (GECMBFR) can reduce the pressure and content of coal seam gas, which is the main measure to prevent gas disaster. Considering the Klinkenberg effect, governing equations of gas adsorption/desorption-diffusion, gas seepage, and stress fields within the coal seam are established to form the seepage-stress coupling model. The governing equations are embodied into a finite element driven software to numerically simulate gas migration and fluid-solid coupling law in coal seam. On this basis, the process of gas extraction under different borehole spacings and diameters is simulated. The effects of these two key parameters on coal seam gas pressure, gas content, and gas permeability were analyzed. The borehole spacing and diameter were determined to be 5 m and 0.09 m, respectively. Combined with the actual situation of a mine, the process of gas extraction from floor roadway with different cross-sectional schemes, ordinary drilling boreholes and punching combined drilling boreholes, is comparatively analyzed. The results show that the gas extraction effect by ordinary drilling boreholes is lower than that of the punching combined drilling boreholes, and the extraction is uneven and makes it difficult to meet the standard. Hydraulic punching was carried out, and coal was washed out of the borehole, which expanded the contact area between the borehole wall and coal seam. The coal seam around the punching borehole is unloaded, which improves coal permeability and accelerates gas migration towards the borehole, thus promoting the efficiency of gas extraction. It is more reasonable to use punching combined drilling borehole scheme when implementing the GECMBFR technology.
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Qi, Rongrong, Xuwen Qin, Hang Bian, Cheng Lu, Lu Yu, and Chao Ma. "Overview of Molecular Dynamics Simulation of Natural Gas Hydrate at Nanoscale." Geofluids 2021 (June 24, 2021): 1–17. http://dx.doi.org/10.1155/2021/6689254.
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As a dynamic research method for molecular systems, molecular dynamic (MD) simulation can represent physical phenomena that cannot be realized by experimental means and discuss the microscopic reaction mechanism of things from the molecular level. In this paper, the previous research results were reviewed. First, the MD simulation process was briefly described, then, the applicability of different molecular force fields in the natural gas hydrate (NGH) system was discussed, and finally, the application of MD simulation in the formation and decomposition law of NGH was summarized from the perspective of NGH mining. The results show that the selection of water molecular force field has a great influence on the simulation results, and the evaluation of water model applicable to the simulation of NGH under different thermodynamic states is still an open research field that needs to be paid attention to. The effect of surface properties of porous media (such as crystallinity and hydrophilicity) on hydrate needs to be further studied. Compared with thermodynamic inhibitors, kinetic inhibitors (such as amino acids) have more promising research prospects, and further research can be carried out in the screening of efficient kinetic inhibitors in the future.
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Libman, A. "Modern Economic Theory: The Main Tendencies." Voprosy Ekonomiki, no. 3 (March 20, 2007): 35–54. http://dx.doi.org/10.32609/0042-8736-2007-3-35-54.
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The paper presents a survey of the main fields of theoretical and empirical research in economics and social sciences. It offers two classifications of economic research based on methodology and segments of scientific community. Advantages and disadvantages of different methodological approaches and standards of communication are considered. The article also discusses the main directions of evolution of mainstream economics, as well as empirical and experimental turn in the modern economic science.
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Sun, Zhensheng, Miao Liu, Peng Liu, Juan Li, Tao Yu, Xingfa Gu, Jian Yang, Xiaofei Mi, Weijia Cao, and Zhouwei Zhang. "SAR Image Classification Using Fully Connected Conditional Random Fields Combined with Deep Learning and Superpixel Boundary Constraint." Remote Sensing 13, no. 2 (January 14, 2021): 271. http://dx.doi.org/10.3390/rs13020271.
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As one of the most important active remote sensing technologies, synthetic aperture radar (SAR) provides advanced advantages of all-day, all-weather, and strong penetration capabilities. Due to its unique electromagnetic spectrum and imaging mechanism, the dimensions of remote sensing data have been considerably expanded. Important for fundamental research in microwave remote sensing, SAR image classification has been proven to have great value in many remote sensing applications. Many widely used SAR image classification algorithms rely on the combination of hand-designed features and machine learning classifiers, which still experience many issues that remain to be resolved and overcome, including optimized feature representation, the fuzzy confusion of speckle noise, the widespread applicability, and so on. To mitigate some of the issues and to improve the pattern recognition of high-resolution SAR images, a ConvCRF model combined with superpixel boundary constraint is developed. The proposed algorithm can successfully combine the local and global advantages of fully connected conditional random fields and deep models. An optimizing strategy using a superpixel boundary constraint in the inference iterations more efficiently preserves structure details. The experimental results demonstrate that the proposed method provides competitive advantages over other widely used models. In the land cover classification experiments using the MSTAR, E-SAR and GF-3 datasets, the overall accuracy of our proposed method achieves 90.18 ± 0.37, 91.63 ± 0.27, and 90.91 ± 0.31, respectively. Regarding the issues of SAR image classification, a novel integrated learning containing local and global image features can bring practical implications.
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Duethmann, D., J. Zimmer, A. Gafurov, A. Güntner, B. Merz, and S. Vorogushyn. "Evaluation of areal precipitation estimates based on downscaled reanalysis and station data by hydrological modelling." Hydrology and Earth System Sciences Discussions 9, no. 9 (September 20, 2012): 10719–73. http://dx.doi.org/10.5194/hessd-9-10719-2012.
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Abstract. In data sparse regions, as in many mountainous catchments, it is a challenge to generate suitable precipitation input fields for hydrological modelling, as station data do not provide enough information to derive areal precipitation estimates. This study presents a method using the spatial variation of precipitation from downscaled reanalysis data for the interpolation of gauge observations. The second aim of this study is the evaluation of different precipitation estimates by hydrological modelling. Study area is the Karadarya catchment in Central Asia (11 700 km2). ERA-40 reanalysis data are downscaled with the regional climate model Weather Research and Forecasting Model (WRF). Precipitation data from gauge observations are interpolated (i) using monthly accumulated WRF precipitation data, (ii) using monthly fields from multiple linear regression against topographical variables and (iii) with the inverse distance approach. These precipitation data sets are also compared to (iv) the direct use of the precipitation output from the WRF downscaled ERA-40 data and (v) precipitation from the APHRODITE data set. Our study suggests that using monthly fields from downscaled reanalysis data can be a good approach for the interpolation of station data in data sparse mountainous regions. Compared to mean annual precipitation from continental and global scale gridded data sets our precipitation estimates for the study area are considerably higher. The introduction of a calibrated precipitation bias factor for the comparison of different precipitation estimates by hydrological modelling allows for a more informed differentiation with regard to the temporal dynamics, on the one hand, and the overall bias, on the other hand. Uncertainty and sensitivity analyses suggest that our results are robust against uncertainties in the calibration parameters, other model parameters and inputs, and the selected calibration period.
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Wang, Ying, Xuan Feng, Haoqiu Zhou, Zejun Dong, Wenjing Liang, Cewen Xue, and Xiaotian Li. "Water Ice Detection Research in Utopia Planitia Based on Simulation of Mars Rover Full-Polarimetric Subsurface Penetrating Radar." Remote Sensing 13, no. 14 (July 8, 2021): 2685. http://dx.doi.org/10.3390/rs13142685.
Full textAbstract:
The probe of China’s first Mars exploration mission, Tianwen-1, has been successfully launched. It will carry out scientific exploration on the topography, soil characteristics, water ice, climate, ionosphere, and physical fields of Mars. Different from other rovers landing on the moon and Mars, the Zhurong rover is equipped with a full polarimetric subsurface penetrating radar (FP-SPR) system for the first time. The radar’s mission is to depict the shallow subsurface structure of Mars and search for possible water ice. Therefore, in this paper, a 3D realistic structure model is established and numerically simulated based on the possible subsurface structure of Utopia Planitia (the landing area). Influencing factors such as topographical fluctuations, rocks, water ice, and the variation of dielectric constant of different layers are added to the model. The analysis of the acquired FP-SPR data set shows that the two-dimensional principal component analysis (2D-PCA) method can extract effective reflected signals from the radar data with noise interference and improve the data quality. These clearly imaged targets may be water ice blocks, so the application of 2D-PCA to FP-SPR data increases the imaging quality of suspected water ice targets. The results of this paper are the basis for future processing of the measured FP-SPR data on Mars, which will help to identify more details of subsurface structures.
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Karst, Isabel G., Isabel Mank, Issouf Traoré, Raissa Sorgho, Kim-Jana Stückemann, Séraphin Simboro, Ali Sié, Jonas Franke, and Rainer Sauerborn. "Estimating Yields of Household Fields in Rural Subsistence Farming Systems to Study Food Security in Burkina Faso." Remote Sensing 12, no. 11 (May 27, 2020): 1717. http://dx.doi.org/10.3390/rs12111717.
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Climate change has an increasing impact on food security and child nutrition, particularly among rural smallholder farmers in sub-Saharan Africa. Their limited resources and rainfall dependent farming practices make them sensitive to climate change-related effects. Data and research linking yield, human health, and nutrition are scarce but can provide a basis for adaptation and risk management strategies. In support of studies on child undernutrition in Burkina Faso, this study analyzed the potential of remote sensing-based yield estimates at household level. Multi-temporal Sentinel-2 data from the growing season 2018 were used to model yield of household fields (median 1.4 hectares (ha), min 0.01 ha, max 12.6 ha) for the five most prominent crops in the Nouna Health and Demographic Surveillance (HDSS) area in Burkina Faso. Based on monthly metrics of vegetation indices (VIs) and in-situ harvest measurements from an extensive field survey, yield prediction models for different crops of high dietary importance (millet, sorghum, maize, and beans) were successfully generated producing R² between 0.4 and 0.54 (adj. R² between 0.32 and 0.5). The models were spatially applied and resulted in a yield estimation map at household level, enabling predictions of up to 2 months prior to harvest. The map links yield on a 10-m spatial resolution to households and consequently can display potential food insecurity. The results highlight the potential for satellite imagery to provide yield predictions of smallholder fields and are discussed in the context of health-related studies such as child undernutrition and food security in rural Africa under climate change.