Topography

In the second half of the 16th century, Girolamo Righettino, a brilliant draughtsman and theologian (a member of the Order of the Canons Lateran), produced city views with ornamental frames characterised by their rich allegorical programme. The drawings earned him widespread fame and were handsomely rewarded. A recently discovered autograph manuscript by Righettino sheds precious light on his only surviving view-an elaborate plan of Turin (1583). This article offers an introductory portrait of a personality forgotten to history and presents new research that allows us to situate his unique output-at the intersection of art and science, theology and politics, topography and allegory-in the wider context of Counter-Reformation Italy, when the ambitions of absolutist rulers were stoked by the fear of Turkish advances in the Mediterranean.

Introduction 1 Methods 2 Results and Discussion 2 Ecuador SRTM DEM versus GROPO30 2 Introduction 2 Methods 3 Results and discussion 3 Honduras SRTM DEM versus 1:50,000 cartographically derived DEM 5 Introduction 5 Methods 6 Results and discussion 6 Conclusions 10 Dapa case study: Absolute and relative differences between DEMs at the sub-catchment scale 10 Introduction 10 Methods 10 Results and discussion 11 Conclusions 16 Tambito case study: Evaluation of a hole-filling algorithm 16 Introduction 16 Methods 16 Results and discussion 18 Conclusions 21 The hydrologically significant differences between SRTM and carthographically generated DEMs 21 Introduction 21 Methods 22 Results and discussion 22 Conclusions 28 Overall Conclusions 28 References 29 1 Introduction Topography is basic to many earth surface processes. It is used in analyses in ecology, hydrology, agriculture, climatology, geology, pedology, geomorphology, and many others, as a means both of explaining processes and of pr...

The Regional Ocean Modeling System (ROMS) is used to systematically investigate equilibrium conditions and seasonal variations of the Benguela system at a resolution of 9 km, including both the large-scale offshore flow regime and the economically and ecologically important coastal upwelling regime. A shelf-edge poleward flow exists in the northern Benguela region (i.e., north of ∼28°S) and is driven primarily by the wind stress curl via the Sverdrup relation. As such, it is strongly seasonal and is most intense during spring and summer, when the wind stress curl is most negative. The poleward flow deepens as it moves southward; between ∼25° and 27°S, much of it veers offshore because of the nature of the wind stress curl and its interaction with the northwestward path of the Benguela Current, which is influenced by alongshore topographical variations. The Benguela Current is driven by nonlinear interactions of passing Agulhas rings and eddies and does not have a striking seasonal s...

1 The species composition of fragmented semi-natural grasslands may change over time due to stochastic local extinction and colonization events, successional change and/or as a response to changing management or abiotic conditions. The resistance of vegetation to change may be mediated through the effects of topography (slope and aspect) on soils and microclimate.2 To assess long-term vegetation change in British chalk grasslands, 92 plots first surveyed by F. H. Perring in 1952–53, and distributed across four climatic regions, were re-surveyed during 2001–03. Changes in vegetation since the original survey were assessed by comparing local colonization and extinction rates at the plot scale, and changes in species frequency at the subplot scale. Vegetation change was quantified using indirect ordination (Detrended Correspondence Analysis; DCA) and Ellenberg indicator values.3 Across all four regions, there was a significant decrease in species number and a marked decline in stress-tolerant species typical of species-rich calcareous grasslands, both in terms of decreased plot occupancy and decreased frequency within occupied plots. More competitive species typical of mesotrophic grasslands had colonized plots they had not previously occupied, but had not increased significantly in frequency within occupied plots.4 A significant increase in Ellenberg fertility values, which was highly correlated with the first DCA axis, was found across all regions. The magnitude of change of fertility and moisture values was found to decrease with angle of slope and with a topographic solar radiation index derived from slope and aspect.5 The observed shift from calcareous grassland towards more mesotrophic grassland communities is consistent with the predicted effects of both habitat fragmentation and nutrient enrichment. It is hypothesized that chalk grassland swards on steeply sloping ground are more resistant to invasion by competitive grass species than those on flatter sites due to phosphorus limitation in shallow minerogenic rendzina soils, and that those with a southerly aspect are more resistant due to increased magnitude and frequency of drought events. The species composition of fragmented semi-natural grasslands may change over time due to stochastic local extinction and colonization events, successional change and/or as a response to changing management or abiotic conditions. The resistance of vegetation to change may be mediated through the effects of topography (slope and aspect) on soils and microclimate. To assess long-term vegetation change in British chalk grasslands, 92 plots first surveyed by F. H. Perring in 1952–53, and distributed across four climatic regions, were re-surveyed during 2001–03. Changes in vegetation since the original survey were assessed by comparing local colonization and extinction rates at the plot scale, and changes in species frequency at the subplot scale. Vegetation change was quantified using indirect ordination (Detrended Correspondence Analysis; DCA) and Ellenberg indicator values. Across all four regions, there was a significant decrease in species number and a marked decline in stress-tolerant species typical of species-rich calcareous grasslands, both in terms of decreased plot occupancy and decreased frequency within occupied plots. More competitive species typical of mesotrophic grasslands had colonized plots they had not previously occupied, but had not increased significantly in frequency within occupied plots. A significant increase in Ellenberg fertility values, which was highly correlated with the first DCA axis, was found across all regions. The magnitude of change of fertility and moisture values was found to decrease with angle of slope and with a topographic solar radiation index derived from slope and aspect. The observed shift from calcareous grassland towards more mesotrophic grassland communities is consistent with the predicted effects of both habitat fragmentation and nutrient enrichment. It is hypothesized that chalk grassland swards on steeply sloping ground are more resistant to invasion by competitive grass species than those on flatter sites due to phosphorus limitation in shallow minerogenic rendzina soils, and that those with a southerly aspect are more resistant due to increased magnitude and frequency of drought events.

Sustainable construction development is a recent term that is required to create an eco-friendly built environment using renewable and recyclable resources and to reduce energy consumption and waste within protecting the natural environment. This term means such an improvement that pleases the current requirements without limitation of the prospect of sustaining requirements in future. Many problems face builders while executing projects, especially these projects were decided to be built over difficult topographies, such as rivers, falls, inclinations, caves, ridges, cliffs, and mountains. Construction challenges to build a project over a difficult topography are diverse starting by executing piles, retaining walls, conserving stability, and choosing the proper sustainable materials that can withstand the natural environmental factors. This paper sheds the light on the potential of any site's certain criteria; mostly its topography and slope on the provision of sustainable and ...

Phantom islands are falsely mapped islands that turned out non-existent. This paper examines the histories and the etymologies of the names of Bermeja, Hy Brasil, and Sandy Island. Appearing cartographically since 1539, Bermeja's 'undiscovery' blocked Mexico's ownership of an oil-rich section of the Gulf of Mexico. Hy Brasil appeared first in 1330 maps and became falsely associated with Irish mythology. Sandy Island, near New Caledonia, was officially 'unfound' most recently in 2012, but existed on maps since 1908. This paper also examines the residential cruise liner The World, a manmade floating 'island' challenging our notion of place. Though not 'real', these islands exist as hope - Bermeja, a hope for power, Hy Brasil, a hope for a divine land, and Sandy Island and The World, a hope for the unknown. In a largely known, familiar world, discovery is not exploring the new, but revisiting the old; not uncovering what we do not know, but undiscovering what we do.

Key Words: Phantom Islands, Historical Cartography, Bermeja, Hy Brasil, Sandy Island

Outside the professional circles of topography and applied mathematics, the life and work of André-Louis Cholesky (1875–1918) are still relatively unknown to the scientific community. This new book appreciably widens the exposure of his remarkable personal achievements in topography and mathematics to a much larger international audience. Cholesky is also interesting to historians because he is a perfect representative of these ”scientists engineers” that, since the early 19th century, had issued from the French scientific high schools. Because they had received a high level of mathematical education, they were able to innovate in their practice of engineering. In the case of Cholesky, this resulted in original contributions in artillery, topography, numerical analysis and graphical calculation. In addition, the book places his education and works within the history of several European countries through the 17th to 19th centuries. The book begins with Cholesky’s biography, followed by his family's history and an introduction to topography. It continues with a historical analysis of an unpublished paper (translated into English) in which Cholesky explained his method for linear systems. Cholesky’s other works are then described, such as his participation in teaching at a superior ”school by correspondence” founded by Léon Eyrolles. His important unpublished book in French on graphical calculation, which is reproduced in his entirety, is analyzed in detail and compared to similar contemporary publications. The biography of Ernest Benoît, who wrote the first paper on Cholesky’s method, is provided. Various documents, highlighting the life and the personality of Cholesky, round out his story and end the book.

The boat-based, mobile mapping system (BoMMS) with a laser scanner allows the derivation of detailed riverine topographical data for fluvial applications. Combined with data acquisition from static terrestrial LiDAR (light detection and range) or mobile terrestrial LiDAR on the ground, boat-based laser scanning enables a totally new field mapping approach for fluvial studies. The BoMMS approach is an extremely rapid methodology for surveying riverine topography, taking only 85 min to survey a reach approximately 6 km in length. The BoMMS approach also allowed an effective survey angle for deep river banks, which is difficult to achieve with aerial or static terrestrial LiDAR. Further, this paper demonstrates the three-dimensional mapping of a point-bar and its detailed morphology. Compared with the BoMMS surface, approximately, 80% and 96% of the terrestrial LiDAR points showed a height deviation of less than 2 cm and 5 cm, respectively, with an overall standard deviation of ± 2·7 cm. This level of accuracy and rapidity of data capture enables the mapping of post-flood deposition directly after a flood event without an extensive time lag. Additionally, the improved object characterisation may allow for better 3D mapping of the point bar and other riverrine features. However, the shadow effect of the BoMMS survey in point bar mapping should be removed by additional LiDAR data to acquire entire riverine topography. The approach demonstrated allowed a large reach to be surveyed compared with static terrestrial LiDAR and increased the spatial limit of survey towards aerial LiDAR, but it maintains the same or even better temporal resolution as static terrestrial LiDAR. Copyright © 2009 John Wiley & Sons, Ltd.

Edward W. Bork1, Robert J. Hudson2; & Arthur W. Bailey3 1Department of Animal Science, University of Alberta, Edmonton, Alberta, Canada; 2Department of Renewable Resources, University of Alberta, Canada; 3Department of Agriculture, Food, and Nutritional Science, University of ...