GEOG 351 Quiz 1

Cartography

graphic communication of spatial relationships and distributions, including spatial analysis and manipulation of geographic data to enhance representation

art science and tech of producing, using and studying maps

Maps

primary tool for cartographic representation, defined as static model of spatial aspects of real world

Science: remote sensing and GIS

record, store and display data

Science: spatial analysis

analyze location data and patterns

Art: geovisualization and GIS

present info and communicate results

remote sensing and GIS focus on

scale, projection, abstraction, generalization

spatial analysis focuses on

spatial and cartographic analysis

GIS and geovisualization focus on

color, shape, symbology, text and graphics

Cartographic communication: an effective map includes

has a clear motive or goal

directed towards audience

uses appropriate design elements to clearly convey its message

A good map must

be aesthetically pleasing and communicative

must be provocative to tackle reader’s curiosity

use variety of design elements to display real-world data on images

maps have characteristic properties including

location, attribute, relationships, scale, projections, referencing systems, abstractions

Location

position

attribute

quality or quantity

relationships

variations and dependencies

scale

links map to real world in measurable ways

projections

conversion from round earth to flat paper

referencing systems

allows user to locate a position

abstractions

symbols that represent real world entities

GIS

collection of hardware, software, trained personnel and procedures designed to capture, manipulate, analyze, model and display spatially referenced data for solving complex planning and management problems

Model of GIS

vector, raster, real world

GIS for cartography

real world → input→ cartographic models transposed into GIS → output → real world → decision making → map

visualization

collection of scientific techniques and methods developed to explore large multivariate data sets

geovisualization

set of different methods that emphasize spatial context of geographic problems by using representations (paper, computer, media)

1960s

1970s

1980s

1990s

2000s

quantitative revolution - portray geo info correctly

cognitive psychologists - human mental processing of maps

semiology - study of signs and symbols for maps

social construction - power that maps confer

distributed mapping - mapping tools available to masses

How can enhancements to the digital map be of benefit to the individual and to society?

Democratization of (geospatial) data and information

Improving public assess to data and information services

Promoting education and awareness

Enhancing our understanding of real-world processes

Media

format and tech used to communicate info as well as objects on which data can be stored

Multimedia

combine different multiple types of media to present the info in an interactive way

Multimedia cartography

represents, communicates and analyzes geospatial and GIS data in engaging, dynamic and interactive ways

Cybercartography

holistic and dynamic concept dealing with organization, presentation, analysis and communication of spatially referenced information in an interactive, dynamic, multimedia, and multisensory format using various interfaces

Uniqueness of cybercartography comes from fact that it is

holistic and attempts to link cartography, GIS and geography
focuses on community involvement and team-work
not a technology but a concept to achieve a solution to a problem

Multimedia cartography technology

ArcGIS, Google earth, digital maps and atlases, GIS data etc.

Map

primary output of GIS analysis, representation or model of geographic reality portrayed with select features on select flat medium

What and how is represented depends on

goals of map user and who it is represented

Common maps as models

reference and thematic maps

Reference map

measures distance, area, direction, height and other geometric properties

Thematic map

spatial distribution of a single attribute with s supporting data

Type of data chosen for maps determines how they are

used or analyzed

Map scale definition

defines ratio between distance on map and corresponding distance on ground

Fractional scale

numerical expression

Verbal scale

written description

eg. 1 cm to 1 km

graphic scale

calibrated bar on line

scales of relevance

choosing which features to show on map and how they will be represented is generalization or cartographic abstraction

Goal of choosing features

eliminate visual complexity

generalization component: classification

expressing key characteristics of a distribution

generalization component: simplification

determine import characteristics of feature attributes and elimination of non-important ones

generalization component: exaggeration

enlarging or altering features in order to capture real-world importance

generalization component: symbolization

assign graphic marks on maps to features from real world

generalization components: induction

make inferences on relationships among features on map

generalization impacts

why? philosophical objective

when? cartometric evaluation

how? geometric and attribute transformations

• graphic generalization concepts

• conceptual generalization concepts

map communication

target audience

map use cube

map design

increasing level of detail

map components and arranging features

golden section rules

visual field and graphic symbols

map use cube looks at

 

the level of interaction with the map

 the extent of the data relationships to be shown

 the target audience

map design process question

how do i say what to whom and is it effective?

geovisualization

way how map designed depends on purpose of map and who are map users

translating geospatial data into maps, applying cartographic methods and techniques

cartography

information transferred centered about spatial database which can be considered in itself a multifaceted model of geographic reality

serves as core of an entire sequence of cartographic processes, receives various data - outputs various types of info production

map design as an integrated process

geovisualization, spatial analysis, cartography, GIS

map design as an integrated process: golden section rule

• proportion of smaller to larger unit has to equal the same as that of the larger unit to the entirety BC/AB = AB/AC

  equal to = 0.618

map design as an integrated process: choosing proper layout what is important?

position of titles, legends, insets, scale and orientation important for achieving visual balance

map design as an integrated process: lettering the map

process of selecting a typeface design, preparing the names, placing it at right position on map

visual field

map user eye follows path through visual field, look passes through optical center so map elements should be arranged to correspond to natural eye movement

graphic arrangement affects perception: figure-ground relationships

most important feature is in foreground of reader’s attention

arrange supporting map details to be displayed in abckground

guidelines for map content and element arrangement

establish visual hierarchy and commensurate graphical solutions

render important map elements to be visually dominant

graphic variables consist of

shape, color, size, texture

visual variables consist of

size, distance, order, quality

symbology is

process of rendering graphic variables

primary variables

orientation, size, shape, lightness or value, color hue, color chroma

secondary variables

texture, orientation, arrangement

measurement scales

quantitative, qualitative, ordinal

perceptual grouping by similar size

group similar size symbols to allow for recognition of patterns and clusters

perceptual grouping by proximity

elements closer together perceived as single grouping allow for recognition of patterns and clusters

color

perceptual phenomenon and a product of our mental processing of electromagnetic radiation detected by our eyes

presence of color requires

light source, object, observer

primary colours

color belonging to any of two groups each of which is regarded as generating all colours

additive primary colours

physiological, or light primaries red, green, and blue lights of red, green, and blue wavelengths may be mixed to produce all colors

subtractive primary colours

magenta, yellow, and cyan

substances that reflect light of one of these wavelengths and absorb other wavelengths may be mixed to produce all colors

RGB

for digital display of colours (red, green, blue)

CMYK

for color printing and press (cyan, magenta, yellow, key)

traditional color variables

hue, brightness and saturation

additional color variables

transparency: proportional opaqueness of map layers

shading: enhancement of the contrast between objects (figure-ground relationship)

why an understanding of color

communicates emotions and behaviours

good map layout elements

Map title – gives the essence of the map
Neat line – uses borders and boxes to organize the map content
Map body – principal map on the layout
Legend – explains what the symbols on the map mean
Directional indicator/North arrow – gives the orientation of the map
Scale – outlines the level of detail of the map
Additional images, visual variables – visually communicates the map’s message Labels and text – describes the important aspects of the map features
Inset map –additional map at smaller scale to provide larger geographic context Graticule – shows a grid of spatial coordinates for orientation
Other information/Metadata – data source, data, date of data, projection, ancillary text

user experience design is a process focusing on

understanding who are the end users

develop experiences and ideas to solve the end user needs

assess whether the developed solutions work

first step to map creation/layout

wireframe design

geodesy

science of measuring the earth’s size and shape as well as distribution of gravitational field

georeferencing process

set of methods that allow transforming of spatial data and features from curved Earth’s surface into geographic or projection system determining their position on flat surface of a map

georeferencing process 1

define shape and size of earth

shape and size of earth

key in determining the relationship between digital maps and what they represent in the real world

1. autalic sphere

3D surface where all points are equidistant from centre of sphere

why are globes highly accurate?

they preserve size, shape and relationships

why are globes problematic and how are issues overcome?

hard to move around, time consuming to make

but map projections move 3D to 2D

2. ellipsoid

when sphere parameters a is not equal to b

3. geoid

based on equipotential surface of Earth’s gravity field at global mean sea level

accurately represents earth’s shape and size

sphere used for

small scale maps

ellipsoid used for

large scale maps of topography

geoid used for

reference for horizontal and vertical sound surveying

2 factors of ellipsoid

choice of ellipsoid

fit of geoid shape to the ellipsoid and Earth’s center

Datum

set of parameters defining reference system specifying position on Earth’s surface with use of control points whose geometric relationships are known

determined by chosen ellipsoid which approximates shape of earth and fit of geoid to ellipsoid in respect to centre of earth

Horizontal datum and example

reference system that measures locations

identifies origin and orientation

NAD 1983

Vertical datum and example

reference system that specifies elevation of specific points on Earth’s surface

NVD83

project the spherical earth to a flat plane: cartographic projections

mapping: take locations of features on Earth’s curved surface and transform onto flat surface