GIS for Environmental GIS for Environmental ScienceScience

ENSC 3603ENSC 3603

Class 10Class 102/12/092/12/09

Today's ObjectivesToday's Objectives

• GPS review, Garmin GPS, Trimble Planning software

• Review questions for Exam 1

GPSGPS

•Global Positioning System

Consists of 24 satellites orbiting about 12,000 miles above the Earth

GPSGPS

P Consists of 24 satellites orbiting about 12,000 miles above the Earth, and five ground stations to monitor and manage the satellite constellation.P Cost: 12 billion Dollars

GPSGPS

Based on ground based navigation systems developed in the early 1940’s.

Inspiration came for GPS as U.S. scientists notice the Doppler effect on the Soviet Sputinik in 1957.

Reagan announced that the GPS system would be made available to the public when complete after the Soviets shot down airline KAL 007 with 267 people on board in 1983.

1994, complete constellation of 24 satellites was in orbit.2000, “selective availability discontinued.

GPS and Landsat GPS and Landsat satellitessatellites

Earth Diameter7,926 mi

LS570 mi

GPS12,000 mi

www.jesseshunting.com/site/gps.html

GPSGPS1- The basis of GPS is “triangulation” from satellites.

2- To “triangulate”, a GPS receiver measures distance using the travel time of radio signals

3- To measure travel time, GPS needs very accurate timing which it achieves with some technology tricks.

4- Along with distance, you need to know exactly where the satellites are in space. High orbits and careful monitoring are essential.

5- Any delays the signal experiences as it travels through the atmosphere must be corrected.

(www.trimble.com)

GPSGPSPeter H. Dana, Ph.D.

http://wwwhost.cc.utexas.edu/ftp/pub/grg/gcraft/notes/gps/gps.html

GPSGPS

Peter H. Dana, Ph.D. http://wwwhost.cc.utexas.edu/ftp/pub/grg/gcraft/notes/gps/gif/difnav.gif

GPS ErrorsGPS ErrorsPeter H. Dana, Ph.D.

http://wwwhost.cc.utexas.edu/ftp/pub/grg/gcraft/notes/gps/gif/gpserror.gif

Sources of Real-Time DGPSSources of Real-Time DGPS

U. S. Coast Guard BeaconLocal FM SignalsSatellite-Based Differential CorrectionsPurchase a Base Station

Coast Guard Maritime Differential Coast Guard Maritime Differential GPS Site Coverage for ArkansasGPS Site Coverage for Arkansas

U.S. CoastGuardhttp://www.navcen.uscg.mil/dgps/coverage/ark.htm

OmniSTAR Satellite Regional OmniSTAR Satellite Regional CoverageCoverage

http://www.omnistar.com/namerica.html

GPS Accuracies and CostsGPS Accuracies and CostsPeter H. Dana, Ph.D.

http://www.utexas.edu/depts/grg/gcraft/notes/gps/gif/gpsapps.gif

PGeneral Navigation $100 to 1000 100mPDGPS $2500 to 5000 1mPL1 Carrier Phase Survey $10,000 0.1mPL1L2 Carrier Phase Survey $15,000 0.01m1cm accuracy systems $30,000 0.001m

GPSGPS

• Slide show at:• http://www.colorado.edu/geography/gcraft/notes/gps/gps

_f.html

• http://www.trimble.com/gps/ this requires Shockwave and may not work on the lab computers at this time

• Lo, 2002 p. 52

GPSGPS

P http://www.garmin.com/manuals/972_OwnersManual.pdf

Garmin eTrex Legend CxOwners manual PDF

P. 3

P. 3

P. 3

Quit

Menu

P. 3

Graphs, PDOPSky PlotSatellites on 2/14/07Satellite SelectionVisibility GPS G04, 5, 6, 10,14, 24,30,World map

http://www.trimble.com/planningsoftware.shtml

Trimble Office, Planning

MapsMaps• A map's function is to communicate

geographic information – Types

• General - show locational or positional data.e.g. Atlas

• Thematic – shows the structure and distribution of phenomena

– Qualitative -depict different features with different symbols according to some attribute. e.g. Soil series maps

– Quantitative - show differences in features' numeric attributes. e.g. Population density for each county in a state

ReviewReview1. What is a GIS?

2. Data is one of the four components of a GIS as an information System. Name the other three.

3. What kind of analysis would be best to create a land suitability map for agricultural development if you had information about soil, topography and land cover? a. Overlay analysis, b. Query, c. Network analysis, d. Proximity analysis

4. Conic is one of the three main types (categories) of projections. Name the other two.

5. A small scale map is best to represent the University of Arkansas main campus. a. True, b. False

6. The last phase of GIS development is Management. What are the other two phases?

7 ‘Surface’ is a type of GIS data. Name the other two types.

8. What is the purpose of a map projection?

9. What is a Coordinate system?

ReviewReview10. Why is the Universal Trasnsverse Mercator (UTM) a good coordinate

system to use for Arkansas?

11. A ______________ data model treats geographic space as populated by discrete and identifiable objects.

12. A__________________ data model treats geographic space as populated by one or more spatial phenomena, which are real-world features that vary continuously over space with not specific extent.

13. A description of our view of the real world is a ________ __________.

14. Of the two common types of maps, a ___________ map shows locational or positional data while a_____________ map shows structure and distribution of phenomena.

15. What is a map’s function?

16. a) A _________________ is a spatial object with specific properties

b) A _________________ is a description of 16a above.

c) A _________________ is spatial association among the answer of 16a.

ReviewReview17. In Topological Overlay Operators for polygon on polygon:

_________________ keeps all features in both layers

_________________ Keeps only parts of the first layer falling within the second layer

_________________ Cuts out a piece of the first layer based on the second, Cookie Cutter.

18. Points are one of the three vector data graphical elements (basic geometry types), name the other two?

19. The vector data graphical elements are also known as _______ _______

20. In GIS spatial relationships,

When neighboring polygons share a boundary it is called ___________________

The inclusion of one spatial object within another is called __________________

Linkages among spatial objects is called ____________________

ReviewReview21. A pixel or _________is the smallest unit of information available in an

image or raster map.

22. One image compression technique is called quad tree, name another technique.

23. Raster data model is best for

a) Topology

b) Precision if graphics

c) Continuous space

d) a and c

24. Vector data model is best for

a) Traditional cartography

b) Topology

c) Continuous space

d) a and b

ReviewReview25. Of the ArcGIS component applications: ArcCatalog, ArcMap and

ArcToolbox, which application is best used to display, edit and query geographic data on maps ( Circle one) ?

26. A ______________ system includes a spheroid, datum, projection and units.

27.While working with feature attribute tables, when fields from one table are appended to another table it is called a ____________(choose one: join, relate)?

28.Selecting features based on their location is called a ___________(choose one: spatial query, attribute query).

29. What kind of analysis would you perform if you where looking for locations with a beautiful view?

30.The geodatabase data model of ArcGIS 9.3 is and example of a __________-___________ data model.

31. Network, Object-Relational and Hierarchical data models are examples of a ___________ data model (choose one: Conceptual, or Logical ).

ReviewReview32. A collection of persistent data stored in a DBMS so it can be shared and

used by different users in an organization is a__________________________?

33. A geometric distortion of remote sensing involving the rotation of an aircraft that causes a wing-up or wing-down attitude is a ___________________?

34. Name two things you can learn from a classification histogram.

35. What are the two most important factors to consider when choosing a map projection?

36. The rate of change on a topographic surface (rise over run) is _________.

37. In surveying, an_____________ uses two distances and right angle.

38. A ___________is an abstract representation of some real thing.

39. What is Geographic Data?

40. When would you use the vector data model versus the raster data model?

41. To “triangulate, a GPS receiver measures distance using laser light between Satellites and your GPS receiver.

Exam Next Tuesday the 17thExam Next Tuesday the 17th

• Look at class notes, first quiz, chapters in Lo, ESRI tutorial review for each lesson through module 4.

• Module 5 is due February 19th.

“Facts can be ignored but we cannot escape there consequences. If the facts don’t matter, this means that the people who are going to have to pay those consequences don’t matter.” Thomas Sowell