Describing change using geographical objects

1. GEOBIA 2012, Rio de Janeiro Describing change using geographical objects Gilberto Camara INPE – National Institute for Space Research

2. The fundamental question of our time How is the Earth’s environment changing, and what are the consequences for human civilization? source: IGBP

3. Global Change Where are changestakingplace? Howmuchchangeis happening? Who isbeingimpactedbythechange?

4. Geoinformatics enables crucial links between nature and society Nature: Physical equations Describe processes Society: Decisions on how to Use Earth´s resources

5. Earth observation satellites and geosensor webs provide key information about global change… …but that information needs to be modelled and extracted

6. Communicating change is hard When did the Aral Sea reach the tipping point?

7. Describing events and processes is very hard When did the flood occur?

8. What types of change can be described using geo-objects? What is the role of GEOBIA in describing change?

9. Geo-objects in animage LandsatImage 13/Ago/2003

10. Geo-objects in animage Deforestation 13/Ago/2003 until 07/Mai/2004 Deforestation in 13/Aug/2003 (yellow) + deforestation from 13/Aug/2003 until 07/mai/2004 (red)

11. Geo-objects in animage Deforestation on21/May/2004 Deforestation in 13/Aug/2003 (yellow) + deforestation from 13/Aug/2003 until 07/May/2004 (red)+ deforestation on 21/May/2004 (orange)

12. Land change objects LAND CHANGE OBJECTS Boundaries determined by agreement about land categories (geometry, topology and properties change)

13. Images as a source for geo-objects G Câmara, M Egenhofer, F Fonseca, A Monteiro. "What´s in An Image?“COSIT 2001. “Images have an observer-independent ontological status”

14. What’s in an image? Images = actsofmeasurement Segments=mathematicalconstructs

15. Structur. Ontology Applicat. Ontology Semantic Mediator Method Ontology Physical Ontology Task Ontology Ontology-Based Image Analysis Segments (mathematical constructs) Objects (conceptual constructs)

16. Extractingpatternsfromsequencesofimages M. Silva, G.Câmara, M.I. Escada, R.C.M. Souza, “Remote Sensing Image Mining: Detecting Agents of Land Use Change in Tropical Forest Areas”. International Journal of Remote Sensing, vol 29 (16): 4803 – 4822, 2008.

17. Linkinghumanactionstolandchange

18. Remote sensing image mining M. Silva, G.Câmara, M.I. Escada, R.C.M. Souza, “Remote Sensing Image Mining: Detecting Agents of Land Use Change in Tropical Forest Areas”. International Journal of Remote Sensing, vol 29 (16): 4803 – 4822, 2008.

19. Patterns of tropical deforestation

20. Spatial patterns in the Vale do Anari irregular, linear, regular

21. Decision tree for Vale do Anari

22. Vale do Anari – 1982 -1985 REG Patterns/Typology IRR: Irregular – Colonist parcels LIN: Linear – roadside parcels REG: Regular agregation parcels Pereira et al, 2005 Escada, 2003

23. Vale do Anari – 1985 - 1988 REG Pereira et al, 2005 Escada, 2003

24. Vale do Anari – 1988 - 1991 REG Pereira et al, 2005 Escada, 2003

25. Vale do Anari – 1991 - 1994 REG Pereira et al, 2005 Escada, 2003

26. Vale do Anari – 1994 - 1997 REG Pereira et al, 2005 Escada, 2003

27. Vale do Anari – 1997 - 2000 REG Pereira et al, 2005 Escada, 2003

28. Confirmed by field work Vale do Anari – 1985 - 2000 REG Pereira et al, 2005 Escada, 2003

29. Land change patterns: Anari (1985-2000) Marked land concentration Government plan for settling many colonists in the area has failed. Large farmers have bought the parcels in an illicit way

30. Discovering the history of land change objects "Case-Based Reasoning for Eliciting the Evolution of Geospatial Objects".  Joice Mota, Gilberto Câmara et al,  COSIT 2009. Reconstructing the history of a landscape using topological information of geo-objects

31. When was this area converted from food to biofuel production? Coverage set (remote sensing images)  Time Series (vegetation index)

32. Geographic Data Mining Analyst (GeoDMA)

33. Visualizing time series in polar coordinates

35. Objects and events The coast of Japan is an object The 2011 Tohoku tsunami was an event

36. Processes and events Flying is a process - Virgin flight VX 112 (LAX-IAD) on 26 Apr 2012 is an event

37. Aral Sea (an object) – disaster (an event) When did the Aral Sea shrank to 10% of its original size?

38. objectsexist, eventsoccur Mount Etna is an object Etna’s 2002 eruption was an event

39. A view on processes and events (Worboys & Galton) Space Time Count Mass football or game? water or lake?

40. A pragmatic view on objects and events Space Time Observable Abstract football or game? water or lake?

41. Object (GPS buoy) + event (tsunami)

42. source: USGS Events are categories (Frank, Galton) identity : id · a = a composition : ∀a, ∀b, ∃c, c = a.b associativity : a · (b · c) = (a · b) · c

43. Building blocks: Basic Types type BASE = {Int, Real, String, Boolean} operations: // lots of them…

44. Building blocks: Geometry (OGC) type GEOM = {Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon} operations: equals, touches, disjoint, crosses, within, overlaps, contains, intersects: GEOM x GEOM → Bool

45. Building blocks: Time (ISO 19108) type TIME = {Instant, Period} operations: equals, before, after, begins, ends, during, contains, overlaps, meets, overlappedBy, metBy, begunBy, endedBy: TIME x TIME → Boolean

46. What do ST objects have in common? type STobj [T: TIME, G: GEOM, B: BASE] operations: getObs: ST → {Obs} begins, ends: ST → T where: ST x T → G after, before: ST x T → ST during: ST x Period → ST value: ST x T → B

47. Moving objects MOVING OBJECTS Objects whose position and extent change continuously

48. Land change objects LAND CHANGE OBJECTS Boundaries determined by agreement about land categories (geometry, topology and properties change)

49. HowmanywalrusesreachedBaffinisland?

50. When did the Aral Sea shrank to 10% of its original size? areaAral: STObject → Time areaAral obj: { area0 = area (obj1.begin()); for t = obj.begin(); t <= obj.end(); t.next() if area (obj1.begin()) < 0.10*area0) return t; }