The idea to verify the height of the highest peaks (summits) in the Crown of Polish Mountains arose after analyzing sources regarding the date and method of measuring the height of these mountain ...peaks. Our investigations revealed that this type of material is not usually available, and the first mention of height values is most often noted in the inter-war period, and occasionally before WWI (when Poland did not exist as an independent state); most of these values are still in use to this day. The problem of accurate measurement of the height of mountain peaks concerns not only the peaks analyzed by the authors, but also almost all mountain peaks worldwide. Therefore, as part of this work, several trips were organized to the highest peaks of several dozen mountain ranges in the territory of Poland. Measurement was made using a precise geodetic GNSS receiver an accuracy of within 10 cm and a DTM model based on ALS (airborne laser scanning). The results showed that commonly published heights can differ by up to several meters from the actual ones. The most important element of this work consists of the establishment of new measurements of the heights of the highest peaks of all mountain ranges in Poland, which may result in an alteration of the officially recorded heights based on this article. Apart from verification of these heights, this work also aimed to address the issue of the heights of all characteristic objects whose heights must be verified by using modern satellite techniques.
Time is the basis of satellite navigation systems. In precision studies, it is additionally important to ensure accuracy at the highest possible level, up to sub-millimetres. For this purpose, ...corrections of the clocks of satellites and GNSS reference stations are made available. This type of data is made available in real time in a navigation dispatch with an interval of 10 min–2 h depending on the GNSS system, or in a precision orbit file (interval of 15 min) or in the form of clock correction files (30 s or 300 s). This paper analyses the long-term stability of the clocks of satellites of four GNSS systems. For this purpose, IGS reprocessing data from 1994 to 2020 were used and ADEV (Allan deviation) and three related variances were adopted. The study showed the different nature of the satellite correction for each GNSS system and the increase of the stability over time.
The application of Airborne Laser Scanning methods (ALS) in archaeology has opened a new chapter for prospective research in forest areas. Previously, these were under-explored due to the lack of ...effective methods for recording archaeological remains in forests. With LiDAR data, researchers can now use available analytical tools. Also, they have developed new tools by creating so-called image derivatives, which have expanded the possibilities of microrelief interpretation for the identification of archaeological objects. This paper presents the results of DTM analyses and field investigations that were carried out at the Osie archaeological site (Poland). The site was discovered thanks to DTM analyses, which made it possible to identify an extensive settlement complex from the Late Roman Period. The object of our research was to identify remains connected with modern forest management in the form of traces of ploughing. The aim was to see how spatial data analyses, by means of which we identify ploughing traces, correlate with the results of archaeological surveys.
One of the limitations of satellite techniques in archaeological investigations is the land cover. Heritage objects may be more or less visible depending on the land cover type. Low vegetation, such ...as grass or small shrubs, will usually allow us to determine the location of archaeological objects if the difference in height between the object and vegetation is not significant enough. Forest or high vegetation cover makes it more challenging to determine the location of potentially artificial structures. This project's study area covered 50^70 km of the lower reaches of the Vistula River, Poland. The authors searched for anthropogenic objects close to watercourses and analysed nine different (point, line and surface type) objects having a defensive, sepulchral or settlement function. Circular objects, ditches and earth embankments, burial mounds and strongholds of regular forms were found during this research. Based on nine different models processed with LiDAR-based DEMs, several characteristics and relationships of various types of objects were demonstrated. Moreover, optimal models for searching for archaeological objects in forest areas were defined.
Landscape archaeology (archaeogeography) is a multidisciplinary study used by prehistorical, classic, and historical archaeologists. Archaeogeography deals with the study of how people have shaped ...and used their environment throughout history. It focuses on the relationship between the material culture of a given community and the changes it introduces in its spatial environment. Traditionally search for archaeological sites is mainly carried out using surface research, i.e., observation of ploughed fields in spring and autumn. However, the percentage ratio of the area covered by forests to the total area of the countries can reach up to even several dozen per cent. This is where archaeogeography aided with modern remote sensing data and processing techniques can be most useful. In this article, the authors describe the problems occurring while searching for anthropological objects in forest areas. In this first part of the two-part series, the authors present a non-invasive method based on widely available remote sensing and historical data that can be used for remote prospection or archaeological sides. The authors also present methods of field verification and critically describe the limitations and advantages of this method.
Advances in remote data acquisition techniques have contributed to the flooding of society with spatial data sets and information. Widely available spatial data sets, including digital terrain models ...(DTMs) from aerial laser scanning (ALS) data, are finding more and more new applications. The article analyses and compares the heights of the 14 highest peaks of the Polish Carpathians derived from different data sources. Global navigation satellite system (GNSS) geodetic measurements were used as reference. The comparison primarily involves ALS data, and selected peaks’ GNSS measurements carried out with Xiaomi Mi 8 smartphones were also compared. Recorded raw smartphone GNSS measurements were used for calculations in post-processing mode. Other data sources were, among others, global and local databases and models and topographic maps (modern and old). The article presents an in-depth comparison of Polish and Slovak point clouds for two peaks. The results indicate the possible use of large-area laser scanning in determining the maximum heights of mountain peaks and the need to use geodetic GNSS measurements for selected peaks. For the Polish peak of Rysy, the incorrect classification of point clouds causes its height to be overestimated. The conclusions presented in the article can be used in the dissemination of knowledge and to improve positioning methods.
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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