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Time and maps Menno-Jan Kraak Time and maps Why interested in time? What is time and How is time perceived? How is time represented? Use case: movement data Why interested in time? GIScience perspective: Better understanding of human influence on the environment at all scales (local and global change) - analysis of changes over time - analysis of patterns of change over time Development of methods / techniques / tools to be able to support problem solving - geospatial data handling - visualization Context: GIScience perspective: For many (global) challenges reference to location - and time - is the glue that connects disparate, often incomplete data sources of continually changing information about time-critical, evolving real world situations source: new york times Earthquake & Tsunami Chili 27 Feb 2010 source: New York Times What is time? What is time? Everyone knows what it is, and few can define it what, then, is time? - if no one asks me, i know - if i wish to explain it to one that asketh, i know not [st. augustine 400] Time is about change

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Page 1: OGiC - Menno-Jan Kraak - Maps and time

Time and mapsMenno-Jan Kraak

Time and maps

• Why interested in time?

• What is time and

• How is time perceived?

• How is time represented?

• Use case: movement data

Why interested in time?

GIScience perspective:

• Better understanding of human influence on the environment at all scales (local and global change)- analysis of changes over time - analysis of patterns of change over time

• Development of methods / techniques / tools to be able to support problem solving- geospatial data handling- visualization

Context: GIScience perspective:

• For many (global) challenges reference to location - and time - is the glue that connects disparate, often incomplete data sources of continually changing information about time-critical, evolving real world situations

source: new york times

Earthquake & Tsunami Chili 27 Feb 2010source: New York Times

What is time?

What is time?

• Everyone knows what it is, and few can define it

• what, then, is time? -

• if no one asks me, i know -

• if i wish to explain it to one that asketh, i know not

[st. augustine 400]

• Time is about change

Page 2: OGiC - Menno-Jan Kraak - Maps and time

128 entries found in The New Oxford Dictionary of English

• time noun

• [mass noun] the indefinite continued progress of existence and events in the past, present, and future regarded as a whole

• a point of time as measured in hours and minutes past midnight or noon

• [mass noun] time as allotted, available, or used

• an instance of something happening or being done; an occasion

• ......

Past, present, future

• How, then, can these two kinds of time, the past and the future be, when the past no longer is and the future as yet does not be?

[Saint Augustine, 400]

• Time as static (the now) versus time as dynamic (as flow)[Scientific American - A matter of Time, 2006]

Schools of thought

• absolute timeInfluenced by Newton they see time and space as a kind of container in which objects exist and move, guided by the laws of physics. Space and time function as a kind of reference frame. In other words, time is independent of any physical object, but it describes the ‘location’ of objects and events during their existence

• relative time Influenced by Aristotle, who said that time is measure of change, which in turn implies that time does not exist when there is no change. Leibniz and Kant were followers of this viewpoint. Space and time describe relations among objects

Perception of time

45 minutes

9 0 m i n u t e s

(this lecture)

Perception and structure of time

• Time has an inherent semantic structure, which is one source of increased complexity.

• By convention, time has a hierarchical system of granularities

- seconds, minutes, hours, days, weeks... (but different calender systems)

• Time contains natural cycles and re-occurrences.

- regular and relatively predictable: seasons,

- less regular: social cycles like holidays or school breaks or economic cycles, hurricane season

Sense of time

• Timetables and rhythmsinter-relation between time and space such as seasons, tides, body, (island-boat)

• Social discipline monastery, factory, office, home

• Instruments and devicessun dial, vcr, satellite broadcast

• Texts

(from May, J. and N. Thrift, 2001. Timespace : geographies of temporality. Routledge, London)

Page 3: OGiC - Menno-Jan Kraak - Maps and time

Social time

• Time talks with an accent

- every culture has its own unique set of temporal finger prints

- to know a people is to know the time values they live by

Levine, R. (1997). A geography of time the temporal misadventures of a social psychologist, or how every culture keeps time just a little bit differently. Basic Books, New York

Time

• Time is about change > event

Water Resources, Vol. 32, No. 2, 2005, pp. 200–203. Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 223–226. Original Russian Text Copyright © 2005 by Semenchenko, Moroz.

Atlas to Alison's History of Europe, 1850; Plaste 78 - Passage of the Beresina, 26, 27 & 28 November 1812.

2011 sabbatical trip Berezina River, Belarus

track process battle

Events Change

Temporal dimension

• Temporal primitives

- Time point is an instant in time

- Time interval is a temporal primitive with an extent

• The choice of appropriate primitives must depend on the properties of the data and the problem at hand.

• Temporal structures exist

- Ordered time: linear and cyclic time

- Branching time

- Multiple perspectives.

Temporal scale

Page 4: OGiC - Menno-Jan Kraak - Maps and time

Calendars Types of time I

Structure of the temporal dimension (multiple perspectives)

• Time with multiple perspectives allows more than one point of view at observed facts (people’s observations about hazard events)

A > B > C> DDD > A > C > B

Types of time II

Different types of times

tekst

[Frank, A. U., 1998]

total order partial order branching multiple perspective

linear ordinal single experience

multiple experience

brancing time time with multiple prespectives

linear

continious continious timecontinious time

brancing time time with multiple prespectives

cyclic ordinal cyclic timecyclic time

brancing time time with multiple prespectives

cyclic

continious

cyclic timecyclic time

brancing time time with multiple prespectives

Types of time?

• Valid time

• Transaction time

• World time

• Database time

• Observation time

• Display time

• Historical time

• Excavation time

• Mechanical time

• Biological time

• Body time

• Social time

• Life time

• Sense of time

• Web time

• .......

Page 5: OGiC - Menno-Jan Kraak - Maps and time

Different types of time Different types of time

Observe / measure time / change

• Change can happen suddenly or gradually

• Change of some sort is always happening

• Change can be observed after the fact

• Change can go unrecorded

Spatio-temporal data and questions

Temporal questions

• When was the last forest fire in the neighborhood?

• Which areas were affected by mudflows in the week after the storm?

• In which neighbourhoods did the unemployment rise after closing the factories?

Temporal questions

Page 6: OGiC - Menno-Jan Kraak - Maps and time

Issues of representation

• State (static)What was / is / will be the spatial distribution of a given phenomena at a given time?

• Change (dynamic)Which elements changed / are changing / will change during a given time span?

spatio-temporal data

Working environment for visual exploration

Time space

Location space Attribute space

M A P D I A G R A M

T I M E G R A P H

Working environment for visual exploration

Evaluation: time graph in its environment

!

!

When and where?

When and what?

!

When?

!

What to do?

D A T A

- Linear and cyclic

- Instant and interval

- Absolute and relative

- Continuous and discrete

- .....

U S E R T A S K

• When

• How long

• How often

• What order

• .....

V I S U A L I Z A T I O N

• Time line

• Time wheel

• Diagrams

• Maps

• .....

Page 7: OGiC - Menno-Jan Kraak - Maps and time

How is time represented?

How to map events

Map AppearanceInformation retrieval

graphical variables

memory deduction

spatial deduction

memory deduction

graphical variables

graphical variables

graphical variables

plane

plane

plane

time location attributesingle map

animation

small multiple (series of maps)

I

III

II

Single map Series of maps

Animation Interactive animation

Page 8: OGiC - Menno-Jan Kraak - Maps and time

Dynamic linked views Map reading and time

Animation Historical geography

! study through time of human relationships to physical environment and human organization of an area

! time as a line / dating an event: moments

when did the conference take place?

! duration: how long and event takes place

how long does it take for an event to occur in how much space?

(sample: epidemic)

Historical situations Reconstructing history

Page 9: OGiC - Menno-Jan Kraak - Maps and time

Mapping uncertainty Compiling change

Cultural geography

! impact of human culture on natural environment and how space is organized

! internal processes: perceiving time

! external processes: structured time

time table

time zone

Experiencing time

45 minutes 9 0 m i n u t e s

Time zonesWhere is my package? dhl from schiphol to….

morning, afternoon, evening

Page 10: OGiC - Menno-Jan Kraak - Maps and time

Time geography

! time as measurement of human activity

what did people do and how long did it take?

! time as a measure of distance

isochrones (lines of equal temporal distance)

chrono-geographic representation (space time cube)

Time travel

Travelling from enschede (cartogram) France and the tgv in 2015

Distance time relief in france

[L’Hostis]

Space-time-cube

Page 11: OGiC - Menno-Jan Kraak - Maps and time

London travel time Tornado’s in the US

Traffic intensity

Crime over time

http://projects.nytimes.com/crime/homicides/map?hp

Map background

Page 12: OGiC - Menno-Jan Kraak - Maps and time

What, where and whenTroia – valley of scamander coastline changes trough time

Spatial Analysis & Cartography Laboratory (ErGAX)FOUNDATION OF THE HELLENIC WORLD

Troia – prehistoric period

Troia

Troia – homeric period

Spatial Analysis & Cartography Laboratory (ErGAX)FOUNDATION OF THE HELLENIC WORLD

Troia Troia

Troia – roman period

Spatial Analysis & Cartography Laboratory (ErGAX)FOUNDATION OF THE HELLENIC WORLD

Troia

Spatial Analysis & Cartography Laboratory (ErGAX)FOUNDATION OF THE HELLENIC WORLD

Troia – present day situation

Troia

Movement data

Page 13: OGiC - Menno-Jan Kraak - Maps and time

GIScientist and the domain specialist

User

Problems

Data

Visualization environment

Problem domain

User tasks

Questions

Visualization solutions

Visualization strategies

Urban Geographer

Get insight in urban space consumption by suburban dwellers

Examples of temporal questions:- Is there a difference in distribution of activities between weekdays and weekends- Are there differences during the day

(See Figure5)

Planning in Tallinn, Estonia

The network or the objects Aspects of the networks

what?

where? when?

Traffic congestion at 8.00am on Monday in Tallinn

Traffic Congestion Level

Heavy congestion

Light congestion

Free flow

Network characteristics

• nodes & segments

qualitative

quantitative

multivariate

ChallengesDensity

(Ahas et al., 2010)

Geographical counts

(Ahas et al., 2010)

Temporal rhythm

Software HiDE (http://gicentre.org/hide/)

Counts by land-use

Individual overview

Software HiDE (http://gicentre.org/hide/) Courtesy of Irma Kveladze

ST overview

Page 14: OGiC - Menno-Jan Kraak - Maps and time

Location

T1T2

T3

T6T5

T4

T7T8

D D D

D

D D

O

T1T2

T3

T6T5

T4

T7T8

D D D

D

D D

O

NetworksMovements Combination

Trajectories

Origin - DestinationI

d)

e)b)

c)

a)

Road network

Attribute

Time

07:0009:00

05:00

11:00

07:00 09:00

Tallinn: Space and time

Explore Explore

Page 15: OGiC - Menno-Jan Kraak - Maps and time

Explore

d)

Time?

• There is no time

• Time is relative

• Time is absolute

• Its all in your head

• What is time?

[Irena Vasiliev, (Cartographica vol 34 no 2 1997]