Arno Peters changed the World! Development Education and the Peters' Projection

Abstract

This paper describes, from a map librarian's perspective, an investigation into the feasibility of the provision of digital mapping for use by students in a British academic library. Establishing the funding has been a significant part of the project. This has included consideration of hardware as well as the pricing structures for the supply of digital cartographic data.     

A vector and raster graphic mapping tool on micro-computers

Abstract

The rapid development of physically-based hydrological information and modelling systems has necessitated enhanced data entry and display systems. A 'mapping tool' is developed for the manipulation and display of spatial information, which is a cost-efficient, self-contained utility system that is suitable for use on micro-computers. It has the ability to be integrated as part of any modelling or information system. Diverse applications using the 'mapping tool' are briefly described including resource management systems for planners, mass balance studies in urban catchments and data entry systems for physically based models.     

User Desires and Graphics Capability in the Academic Environment

Abstract

In this paper the cartographic grids engraved on two antique instruments from Iran for finding the sacred direction and distance to Mecca are discussed. It appears that these grids can be well explained in terms of the Mecca-centred retro-azimuthal orthographic projection described in 1968 by J. E. Jackson. In this projection the lines of constant latitude reduce to a set of ellipses with their major axes parallel to the equator and the lines of the constant longitudes reduce to a set of non-equidistant straight lines parallel to the north-south direction. It is shown that the curves actually engraved on the instrument conform to this projection and can be fairly easily constructed. This interpretation of the grid on the Iranian instruments stands in contrast with another explanation, recently proposed by King (1999), which is based on medieval Arabic concepts such as the so-called 'methods of the zijes'. Insufficiently accurate workmanship makes it impossible to distinguish between the two explanations through the study of the instruments themselves. The newly gained insight into the projection itself, however, shows that a direct relation between the Iranian maps and Islamic mappings insight knows from the ninth century, as suggested by King, does not exit. Thus, it is concluded that it is as yet completely unknown when and where the very idea behind the Iranian cartographic grid was first conceived, and that the quest for their historical background is still open.     

Code as Cartography

Abstract

Provincial Atlas of People's Republic of China (Chung hua ien min kung wo kuo fên shêng di t'u chi). 190 x 265 mm. pp. 251 (84 pages of maps). Peking: Map Publishing Society (di t'u ch'u p'an shê), China, Oct., 1974. 6.30 Yuan     

Typology of Meteorological Weather Forecast Maps Printed in World Newspapers

ABSTRACT

This paper presents the results of the analysis of more than 150 different printed newspaper weather forecasting maps, representing 91 global, national, regional and local daily news periodicals from 33 countries in 4 continents. The classification attention focused both on the character of the localizing background layer of the analysed maps as well as on the meteorological thematic layer. The results identify 12 types of background localizing maps and 47 used types of presentation of meteorological forecast information, only 19 of which were used repeatedly in more than one newspaper. All the findings were documented on comparable cartographic models. Conclusions suitable for practical applications are demonstrated in the discussion.     

Change vector analysis for disaster assessment: A case study of Hurricane Andrew

Abstract

Remote sensing is a powerful and accurate means of collecting data for wildlife management, particularly for large areas which are difficult of access and feature delicate ecosystems.

Giant panda habitat in the People's Republic of China was evaluated by visual interpretation of multitemporal LANDSAT MSS images. The resulting map, combined with ground survey data, provides important information upon which management decisions can be planned.

This case study illustrates that remote sensing techniques can make a significant contribution to the management programme for the conservation of a threatened animal species.     

Seven possible states of geospatial data with respect to map projection and definition: a novel pedagogical device for GIS education

ABSTRACT

Conceptually, the theory and implementation of “map projection” in geographic information system (GIS) technology is difficult to comprehend for most introductory students and novice users. Compounding this difficulty is the concept of a “map projection file” that defines map projection parameters of geo-spatial data. The problem of the “missing projection file” appears ubiquitous for all users, especially in practice where data is widely shared. Another common problem is inadvertent misapplication of the “Define Projection” tool that can result in a GIS dataset with an incorrectly defined map projection file. GIS education should provide more guidance in differentiating the concepts of map projection versus projection files by increasing understanding and minimizing common errors. A novel pedagogical device is introduced in this paper: the seven possible states of GIS data with respect to map projection and definition. The seven possible states are: (1) a projected coordinate system (PCS) that is correctly defined, (2) a PCS that is incorrectly defined, (3) a PCS that is undefined, (4) a geographic coordinate system (GCS) that is correctly defined, (5) a GCS that is incorrectly defined, (6) a GCS that is undefined, and (7) a non-GCS. Recently created automated troubleshooting tools to determine a missing map projection file are discussed.     

Mastering the Niger. James MacQueen’s African Geography and the Struggle Over Atlantic Slavery

Abstract

Since the publication of the first waterway map in 1990, the Inland Waterways of Britain series has expanded to a total of twenty three individual maps, a national route planning map, the first ring atlas and a directory of the inland waterways which explores aspects of preservation, restoration and heritage. Many of the titles have featured in walking guides, directories, promotional literature and web sites. This paper outlines the development of the series from the first map, describing the maps themselves, tracking the evolution of production methodologies, defining marketing and sales strategies and discussing the decision-making processes behind the publication and introduction of new titles.     

A comprehensive framework for exploratory spatial data analysis: Moran location and variance scatterplots

Abstract

A significant Geographic Information Science (GIS) issue is closely related to spatial autocorrelation, a burning question in the phase of information extraction from the statistical analysis of georeferenced data. At present, spatial autocorrelation presents two types of measures: continuous and discrete. Is it possible to use Moran's I and the Moran scatterplot with continuous data? Is it possible to use the same methodology with discrete data? A particular and cumbersome problem is the choice of the spatial-neighborhood matrix (W) for points data. This paper addresses these issues by introducing the concept of covariogram contiguity, where each weight is based on the variogram model for that particular dataset: (1) the variogram, whose range equals the distance with the highest Moran I value, defines the weights for points separated by less than the estimated range and (2) weights equal zero for points widely separated from the variogram range considered. After the W matrix is computed, the Moran location scatterplot is created in an iterative process. In accordance with various lag distances, Moran's I is presented as a good search factor for the optimal neighborhood area. Uncertainty/transition regions are also emphasized. At the same time, a new Exploratory Spatial Data Analysis (ESDA) tool is developed, the Moran variance scatterplot, since the conventional Moran scatterplot is not sensitive to neighbor variance. This computer-mapping framework allows the study of spatial patterns, outliers, changeover areas, and trends in an ESDA process. All these tools were implemented in a free web e-Learning program for quantitative geographers called SAKWeb© (or, in the near future, myGeooffice.org).     

Primitive-based Construction Theory for Diagrams in Thematic Maps

Abstract

To enhance the variety of map symbols and to develop new symbol types, a fundamental understanding of the map symbol construction process is mandatory. Current construction theories focus on diagrams without taking georeferencing or interactivity into account. This paper presents a new methodology for the creation of two-dimensional geometric symbols and diagrams for the application in thematic maps. In this context, 49 diagrams found in cartographic literature were analysed and classified regarding their construction properties. As a result of this research, diagrams can be defined using cartographic primitives which are arranged according to six arrangement principles. Since the variation of the primitive's size according to the data values follows a certain geometric direction, each diagram can be explicitly defined based on the three construction properties 'primitive', 'arrangement principle' and 'data direction'.     

Blending Aggregation and Selection: Adapting Parallel Coordinates for the Visualization of Large Datasets

Abstract

Many of the traditional data visualization techniques, which proved to be supportive for exploratory analysis of datasets of moderate sizes, fail to fulfil their function when applied to large datasets. There are two approaches to coping with large amounts of data: data selection, when only a portion of data is displayed, and data aggregation, i.e. grouping data items and considering the groups instead of the original data. None of these approaches alone suits the needs of exploratory data analysis, which requires consideration of data on all levels: overall (considering a dataset as a whole), intermediate (viewing and comparing collective characteristics of arbitrary data subsets, or classes), and elementary (accessing individual data items). Therefore, it is necessary to combine these approaches, i.e. build a tool showing the whole set and arbitrarily defined subsets (object classes) in an aggregated way and superimposing this with a representation of arbitrarily selected individual data items.

We have achieved such a combination of approaches by modifying the technique of parallel coordinate plot. These modifications are described and analysed in the paper.     

How to Enhance Cartographic Visualisations of Natural Hazards Assessment Results

Abstract

Cartographic visualisations are important tools for the communication of hazard related data among stakeholders. Although these representations are essential for various hazard management tasks, an analysis of existing hazard visualisations showed that they often disregard cartographic principles. This leads to confusion on the part of users through poor representations and consequently to an impairment of the information flow. The objective of this research is to offer suggestions for enhanced hazard visualisations to facilitate hazard management tasks and decision making. Existing cartographic shortcomings are identified based on an extensive analysis of hazard visualisations and an expert survey. These shortcomings are discussed and improvements for important cartographic elements are presented.     

Harveys and Walking Maps

Abstract

Geographical information is connected to everyday life in many ways. Web cartography has made geospatial data more available to the public. In the next few years, the average age of the population will be over 51 years, with more than 15% of the population over the age of 65 years. The fact that the senior population is increasing suggests that online mapping and map viewer design should be aware of the senior population’s visual restrictions, as well as restrictions of other potential map users, including colour-vision-impaired users. This paper describes the senior population’s visual restrictions that can be compared with colour-vision-impaired users and provides guidelines with regard to online mapping and map viewer design for this growing segment of the elderly population.     

The preparation of the town maps for Lysons' Magna Britannia

Abstract

Although methods of map preparation and production in the nineteenth century are generally understood, in truth little is known in detail. A rare opportunity to further understanding of the methods of the day is offered by the analysis of the surviving working documents and correspondence related to the production of town maps for Lysons' Magna Britannia. As methods of compilation and preparation become clearer, some of the resultant town maps appear more original and carefully created than previously thought, forcing a reassessment of their value as historical evidence.     

Classsroom Applications of High Resolution Digital Imagery

Abstract

This article deals with some instructional applications of high resolution, multispectral digital imagery in the authors' respective undergraduate, introductory remote sensing courses. Both authors participated in the U.S. National Council for Geographic Education's Remote Sensing Task Force's high resolution image evaluation program. This paper represents a continuation of the work conducted under this evaluation program.     

BinSq: visualizing geographic dot density patterns with gridded maps

ABSTRACT

Dot maps have become a popular way to visualize discrete geographic data. Yet, beyond showing how the data are spatially distributed, dot maps are often visually cluttered in terms of consistency, overlap, and representativeness. Existing clutter reduction techniques like jittering, refinement, distortion, and aggregation also address this issue, but do so by arbitrarily displacing dots from their exact location, removing dots from the map, changing the spatial reference of the map, or reducing its level of detail, respectively. We present BinSq, a novel visualization technique to compare variations in dot density patterns without visual clutter. Based on a careful synthesis of existing clutter reduction techniques, BinSq reduces the wide variety of dot density variations on the map to a representative subset of density intervals that are more distinguishable. The subset is derived from a nested binning operation that introduces order and regularity to the map. Thereafter, a dot prioritization operation improves the representativeness of the map by equalizing visible data values to correspond with the actual data. In this paper, we describe the algorithmic implementation of BinSq, explore its parametric design space, and discuss its capabilities in comparison to six existing clutter reduction techniques for dot maps.     

Point grid map: a new type of thematic map for statistical data associated with geographic points

ABSTRACT

Social, economic, and environmental statistical data associated with geographic points are currently globally available in large amounts. When conventional thematic maps, such as proportional symbol maps or point diagram maps, are used to represent these data, the maps appear cluttered if the point data volumes are relatively large or cover a relatively dense region. To overcome these limitations, we propose a new type of thematic map for statistical data associated with geographic points: the point grid map. In a point grid map, an input point data set is transformed into a grid in which each point is represented by a square grid cell of equal size while preserving the relative position of each point, which leads to a clear and uncluttered appearance, and the grid cells can be shaded or patterned with symbols or diagrams according to the attributes of the points. We present an algorithm to construct a point grid map and test it with several simulated and real data sets. Furthermore, we present some variants of the point grid map.     

Mapping Everest

Abstract

From its inception in the middle of the 19th century, the Royal Geographical Society (RGS) took a keen interest in the exploration and mapping of the Everest region. This formed an integral part of the many Everest expeditions, some of which had individual surveyors or survey parties attached to them. Many mountaineers took part in this work, particularly those with a scientific background. But it was not until 1961 that a comprehensive map was produced of the Everest region.     

Monitoring thickness and volume changes of the Dongkemadi Ice Field on the Qinghai-Tibetan Plateau (1969–2000) using Shuttle Radar Topography Mission and map data

Abstract

This paper presents the first measurement of multi-decadal thickness and volume changes (1969–2000) of the Dongkemadi Ice Field (DIF) in the Tanggula Mountains, central Qinghai-Tibetan Plateau, China, using multi-source remote sensing data. These include the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) acquired in February, 2000, a DEM generated by digitising analogue topographic maps from 1969, and Landsat ETM+ imagery from 2000. Digital glacier outlines and GIS-based processing were used to calculate an elevation difference map to evaluate the relative elevation error of these two DEMs over ice-free areas. This method was also used to identify regions of glacier elevation thinning and thickening corresponding to glacier mass loss and gain. Analysis of 67,520 points on flat grass and rock terrain surrounding the DIF, with a slope less than 25°, showed a mean elevation difference of –0.90 m and a standard deviation of 5.58 m. A thickness change error within ±6 m was estimated. Between 1969 and 2000, 76.51% of the whole DIF area appeared to be thinning while 23.49% showed thickening. The average glacier surface thinning was –12.58 m with a standard deviation of 18.29 m and the estimated volume loss was 1.17 km³. The standard deviation of volume change was 0.0006 km³ over the DIF. A thinning rate up to 0.41±0.194 m a^?1 or 0.038 km³ a^?1 for the volume loss was observed for the whole ice field, which seems to be evidence for the ongoing retreat of glaciers on the Qinghai-Tibetan Plateau. It was found that the spatial thickness change pattern derived from the remote sensing method was consistent with the thickness change results of the Small Dongkemadi Glacier (SDG) from field measurements. The estimated error of the annual thickness change rate was on the order of 5%. The relationship between elevation change and absolute glacier elevation over typical glaciers was also analysed, showing considerable variability. These changes have possibly resulted from increased temperature and decreased precipitation in this region.