Topic 13.2: Web mapping Flashcards
Describe some issues with mapping spatio-temporal themes
- Resolution of different times can lead to miscommunication
Identify some strengths and weaknesses of animated maps
Strengths:
- can show gradual changes over time
-
Weaknesses:
- Room for miscommunication
What is the importance of time with regards to mapping?
- Time exists in all maps (when was the data captured? when was it published?)0
- Change in attribute or location (continuous or discrete)
- linear or cyclic (huge implications for symbology)
- which are you mapping (world time - based on time familiar with, database time, display time- animation over time, make sure it is linking with database and world time)
Treating time as discrete and linear?
Doesn’t change gradually - are discrete and they are moving forward in time
treating time as cyclic and continuous?
- eg., showing mean temperature over part of the year
- if it was over multiple decades it would be linear
Minard’s 1869: Napoleon’s Russia campaign
- showing the basis of space, time, attribute of the number of people
- Approach used a lot in spatio-temporal mapping
What is a cartogram?
A map that substitutes a attribute for space
eg., travel time, population - rather than having the area be related to spatial, it is related to population
Temporal and Non-temporal animations
Temporal:
- Display, database, and ‘world time’
- Resolution of different ‘times’ can lead to miscommunication
- Easy to create videos - interactivity minimal - limited value
Non-temporal:
- Display time not linked to ‘world time’
- time is static
Display time
time at which display change is initiated - can be inked to chronological time
Duration
Length of time nothing changes in the display - link to ‘world time’ important
Order
Sequence of frames
Frequency
Linked to duration
