4. From Maps to Multimedia Atlases

The need for maps

- Delivery of physical services such as emergency, utility, etc.
- Delivery of abstract services such as fees, credit application, etc.
- Delivery of management services such as land and property taxes.
- Integration of individuals into modern society and management systems.
- Personal navigation.
- Military planning uses.

Types of map classification

- Classified by scale
- Classified by function or use
- Classified by mapping method

Small scale maps

Show large parts of a study area: 1:500,000 to 1:1,000,000.

Large scale maps

Show small parts of a study area: 1:25,000 to 1:50,000

Topographic maps

General purpose maps where major features are depicted including the landforms and surface configuration.
However, some non-visible information such as political boundaries are added.
They are of high accuracy as distances and other elements are calculated.

Cadastral maps

Define the extent, value and ownership of land for taxation purposes.

Navigational charts/cartometric maps

Special purpose maps that allow for efficient and highly accurate measurements of distance for marine and aeronautical maps for safe navigational purposes.
Example: stick charts

Stick charts

Polynesian navigation maps containing locations of islands, winds and ocean currents. They were made and used by Polynesian Indigenous People to navigate the Pacific Ocean by canoe.

Thematic maps

Define the spatial distribution of one or more specific data themes for a geographic area.
Use statistical methods for map production:
- Qualitative (e.g. land cover with ecozone, major agricultural types)
- Quantitative/statistical (e.g. percentage of population change or persons who volunteer)

Mapping methods

- Dot density mapping method
- Isoline mapping method
- Proportional mapping method
- Choropleth mapping method
- Dasymetric mapping method
- Map as a graph

Dot density mapping method

Method used to represent a count of features. For each dot, a specific number-unit value of feature instances is assigned.
The quality of a dot map depends on:
- Choice of appropriate and representative size of dots
- Choice of the unit value for each dot
- Appropriate placement (location) of the dots on the map

Isoline mapping method

Method used when attribute data have to be represented as continuous spatial distribution of Earth features as a series of equipotential lines.
Various interpolation methods (kriging, IDW, spline, etc.) are used to predict values between known sample points.
The quality of an isoline map depends on:
- Location (x,y) of sample measurement points for attribute value (z)
- Choice of interpolation procedure to calculate values between sample points
- Choice of an optimal number of sample points

Proportional mapping method

Method using symbols at different sizes to proportionally represent the magnitude of the attribute. Each symbol is at the true location or represents a conceptual point.
The quality of the proportional map depends on:
- Choice of appropriate symbol to represent the phenomena
- Choice of appropriate scale to represent the magnitude of the attribute (geographic variable)

Choropleth mapping method

Method used to visualize attributes (tabular) data using various statistics and compare spatial variability of the magnitudes of different attributes.
The quality of a choropleth map depends on:
- Size and shape of unit areas
- Number of classes
- Choice of class limits
- Classification methods
Choropleth maps depend on the cartographic classification method for determining class type and size.
Class number and size can be derived in many ways to classify the data:
- Increasing or decreasing rates
- Equal intervals
- Using parameters of normal distribution
- Using quantities

Dasymetric mapping method

Method used to depict quantitative area using boundaries that divide the mapped area into zones of relative homogeneity with the purpose of best portraying the underlying statistical surface.
This type of map represents a hybrid map obtained as an overlay of in-between stepped (choropleth) and smooth (isopleth) maps.

Cartogram

A type of graphic that depicts attributes of geographic objects as the object's area.
- Because a cartogram does not depict geographic space, but rather changes the size of objects depending on a certain attribute, a cartogram is not a true map.

Satirical maps

Bringing maps to life

More definitions of maps

- Medium to depict the human perception of the world
- Evidence of the human cultural activity
- Mathematical conceptualizations of Earth and the Earth's surface
- Conventional image, mostly on a plane, of concrete or abstract phenomena which can be located in space.
- Spatial models of geographic reality
- Geospatial data storage
- Spatial exploratory and analytical tool
- Medium for visual communication of geospatial information and relationships
- Spatial decision-making tool
- Interface of spatial information

Atlas

An intentional combination of maps, structured in such a way that given thematic objectives are achieved.
A combination of maps, text, photographs, tables, graphs and stories about a particular theme. It is a collection of systematically selected maps, arranged on uniform size medium using standard cartographic principles and map layouts and uniform consistent design, generally in bound book format.
The structure of the atlas is expressed by the map scale, the sequence of maps, and the end/target user.

Classifications of atlases

- Format and volume (desk atlas, pocket atlas)
- Spatial coverage (world atlas, city atlas)
- Thematic content (geological atlas, economic atlas)
- Information level (scientific atlas, national atlas)
- Intended use (road atlas, school atlas)
- Producer (commercial atlas, official/governmental atlas)
- Technical quality and price (multi-color atlas, etc.)
- Publication medium (paper, digital or web atlas)

History of atlases

- Atlas is the name of a giant in Greek mythology who held the sky on his shoulders.
- Ortelius' Theatrum Orbis Terrarum ("Theatre of the world") was published in 1570 and is recognized as the first atlas.
- German cartographer Gerardus Mercator used the term atlas for a collection of maps for the first time in 1595.

Primary use of atlases

To locate geographic phenomena such as places, regions, or to understand and display geo-spatial patterns related to physical or socio-economic environment.

Underlying atlas concepts

- Spatial data used to create atlas maps is processed to achieve coherence by using standardized scales, degrees of generalization, common legends and symbolization.
- As a result, the representation of maps in an atlas is standardized. Geographic reality is represented in a consistent manner.
- Sequence: present relevant maps sequentially and so produce a narrative or a story that will explain the geographical phenomena and spatial patterns.
- Comparisons can be achieved as:
- Topical: between themes at the same location (vertical)
- Contemporary: between time periods (vertical)
- Geographic: between locations at the same time period (horizontal)

Tools for comparison and analysis of atlases

- Scale: more important areas are in larger scale.
- Geographic sequence: present most important areas first.
- Topical sequence: present data in a specific sequence to depict relationships between topics.
- Chronological sequence: time machine.
- Color coding and graphical emphasis tool: graphic information hierarchy applies.
- Highlighting tool: enhances figure for subject of interest.

Electronic Atlas of Arkansas

First web atlas, developed by the department of geography, University of Arkansas, appeared for the first time in 1989. It was a collection of static maps accessible online.

Democratization of geospatial data

Appeared in the late 1990s - meant that anyone can be a map user and map creator.

Types of atlases

1. Traditional (e.g. paper)
2. Standalone (e.g. file to download)
3. Web-based (available online)

Multimedia atlas

An information system (MAIS) with a systematic, targeted collection of spatially related knowledge in electronic form, set up for an interactive consultation of a collection of digital maps with multimedia components and databases concerning a certain geographic area or theme allowing a user-oriented communication for information and decision-making purposes.
They dispose of special interactive functions for geographic and thematic navigation, querying, analysis and visualization in 2D and 3D.

Characteristics of multimedia maps and atlases

- Flexibility to choose different spatial data and context by browsing, and using a variety of tools of exploration.
- Interaction with map objects.
- Dynamics can be represented by animations to depict the change context.
- Mediality due to the use of different media to enhance the presentation (sound, speech, music, video clips, etc.)
- Actuality and extendibility make maps and atlases easy to keep updated and enlarged by new datasets.
- Accessibility to a large number of users.
- Individual map design by users allowing for customizing the choice of layers and layouts.
- Continuous scaling by the means of zooming option.
- Metric operations are available by direct calculation of distances or areas.
- GIS functionality can be added for attribute query, overlays, buffering or different modelling scenario building.
- Portability of memory devices (e.g. USB) but still need computers or smartphones to be viewed.
- Accuracy of the maps and content delivered.

Advantages and disadvantages of traditional maps and atlases

Advantages:
- Easy to use.
- Very good graphic resolution.
Disadvantages:
- The physical constraint of the paper format limits the structure and content of the Atlas.
- The paper atlas is time consuming to produce, expensive and not easily accessible to a wide range of users.

Advantages and disadvantages of multimedia maps and atlases

Advantages:
- Available to all.
- Anyone can make multimedia maps and atlases.
Disadvantages:
- The use of multimedia maps and atlases needs a computer, smartphone or tablet and internet to access map and atlas content.
- Important cartographic principles (e.g. correct cartographic projections, generalization, color, scale, etc.) can be easily omitted.

Data interoperability

Allows us to convert data formats to perform spatial analysis and create maps. Deals with the seamless interconnections between people, data and systems. The main goal is to share, preserve, and manage data, information and knowledge.

Considerations about spatial data before use

- What is the age of the data?
- Where did it come from?
- In what medium was it originally produced?
- What is the aerial coverage of the data?
- To what map scale was the data digitized/obtained?
- What projection, coordinate system, and datum were used in the maps?
- What was the density of observations used for its compilation?
- How accurate are positional and attribute gestures?
- Does the data seem logical and consistent?
- Do cartographic representations look "clean"?
- Is the data relevant to the project at hand?
- In what format is the data kept?
- Why was the data compiled?
- What is the reliability of the provider?

Types of spatial data formats

- .pdf
- JSON
- KML
- etc. (shapefile, KMZ,...)

.pdf

Portable Document Format, a proprietary format that allows formatted documents to be transferred over the internet, so they look the same on any computer.
- Very good to contain embedded maps, images, graphs and also to some extent can include animated images, sound and video files.
- Multimedia elements demand a fee.

JSON (JavaScript Object Notation)

Data is embedded in "tags"

KML (Keyhole Markup Language)

Data is embedded in "tags"

Metadata

Data about data - it describes a specific data set.

Uses of metadata

- Identify geospatial resources
- Exchange geospatial resources
- Manipulate geospatial resources
- Catalogue geospatial resources

Stylesheets

Documents that are used to format the metadata as they determine the layout and other style information about the data.