Task Attend the lecture and identify the components of a metadata file and the role of metadata in sourcing geospatial data.
Metadata
[ ppt ]
Source: Trodd N, 2006. Finding data using metadata.
Metadata
[ pdf ]
Source: Longley PA, Goodchild MF, Maguire DJ and Rhind DW, 2001. Ch 7.5 in Geographic Information Systems and Science. John Wiley & Sons, Ltd. p. 154 - 160.
Go Geo!
[ URL ]
Source: Go Geo. Metadata Teaching and Learning resources will be made available on Go-Geo! portal at the end of November 2006. These modules serve as a resource and reference for academics introducing metadata concepts and data management techniques to students.
Task What are we doing? The world we live in is a round globe but we have spent several centuries drawing maps on flat paper. It was back in the C16th when Gerardus Mercator developed a cylindrical projection. Since then each and every time we map a sphere to a flat surface we distort the geography of the things we are trying to describe. This raises two questions - What are the problems caused by these distortions? How can we transform data between different projection and coordinate systems so that all data are spatially aligned? Your primary task is to answer these questions.

You might also like to consider two issues. Firstly, to what extent can modern applications in GI abandon the 'ancient' methods of mapping position? Over several centuries a global location referencing system developed organized around meridians of longitude and parallels of latitude. It works for mariners, cruise missiles and atlas publishers, and doesn't seem to have any serious bugs (unless you consider the fact that the earth isn't a perfect sphere as a bug). As modern GIS handle 3D coordinate geometry there is simply no need to figure the Earth mapped to the plane paper or to any other plane. To put it simply, let us deal with data that originates in a 3D real world by recording it in a global 3D virtual environment. We can always degrade it to a 2D projection on request!

So far you have focused on the representation of physical space. Can you identify examples when an alternative (non-geodetic) representation of space is perfectly adequate e.g. topology?

From Map Projections to Virtual Geography
[ URL ]
Use this applet to experiment with different map projections. It is suggested that you first experiment by entering the easting and northing (longitude, latitude) coordinates of where you live and observe the effect of changing the projection.

Source: Bottomley H, 2002. Java world map projections. <http://www.btinternet.com/%7Ese16/js/mapproj.htm> URL last accessed 14-11-2006.

Transverse Mercator Calculator
[ URL ]

The online Transverse Mercator Calculator is available via the DMAP website. It is a facility for converting latitude/longitude coordinates into coordinates in metres on a Transverse Mercator projection. Just give it a try!

Source: DMAP Transverse Mercator Calculator. <http://www.dmap.co.uk/ll2tm.htm> URL last validated 2004-03-09.

The Shape of the Earth
[ URL ]
A well-written introduction to geodesy - the study of the Earth's shape. With an emphasis on cartography it is not surprising that the graphics are of a good quality.

Source: Furuti C, 1997. The shape of the Earth, in Cartographical Map Projections. <http://www.progonos.com/furuti/MapProj/Normal/TOC/cartTOC.html> URL last validated 14-11-2006.

Map Projection Overview
[ URL ]
A traditional tutorial on map projections with additional material on datums and coordinate systems.

Source: Dana P, 1999. Map projection overview, in The Geographer's Craft. <http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj_f.html> URL last validated 14-11-2006.

Projections and Coordinates
[ pdf ]
Source: Longley PA, Goodchild MF, Maguire DJ and Rhind DW, 2001. Ch 4.7 in Geographic Information Systems and Science. John Wiley & Sons, Ltd. p. 89 - 94.
Coordinate Systems and Map Projections
[ URL ] [ pdf ]

In Chapter 10 of the the first edition of the 'Big Book', Maling treats the subject of coordinate systems and map projections under three major headings. First, he emphasizes the need for economical methods of handling GIS data and describes some of the ways in which economies may be introduced to the transformation process. Secondly, there is a short account of some of the methods of transformation, which may be used in GIS. Thirdly, there is a description of a method of choosing suitable projections for particular GIS applications.

Source: Maling DH, 1991. Coordinate Systems and Map Projections for GIS. Chapter 31 in Maguire DJ, Goodchild MF and Rhind DW, (eds.) Geographical Information Systems: Principles and Applications. John Wiley & Sons, Ltd. , p. 135 - 146. <http://www.wiley.com/legacy/wileychi/gis/Volume1/BB1v1_ch10.pdf> URL last accessed 2004-03-09.

Task
Supplement
Once you understand the importance of map projections and coordinate systems then you should explore how they are handled in a GIS application. Your task is to find out how ESRI ArcGIS does it. You should listen to the free seminar on geographic and projected coordinate systems and then examine the effects of using different spheroids in ArcGIS in the first module of the Virtual Campus course.
Working with Map Projections and Coordinate Systems in ArcGIS
[ URL ]
Source: ESRI (unknown). Working with Map Projections and Coordinate Systems in ArcGIS. ESRI Training Seminar. <http://training.esri.com/acb2000/showdetl.cfm?DID=6&Product_ID=826> URL last accessed 14-10-2006.
Sizing Up the Earth
[ URL ]
Source: ESRI (unknown). Sizing up the Earth, Module 1 in Understanding Map Projections and Coordinate Systems. ESRI Virtual Campus course. <http://training.esri.com/acb2000/showdetl.cfm?DID=6&Product_ID=697> URL last accessed 14-11-2006.
ESRI Projection Engine
[ pdf ]

The ESRI Projection Engine is a developer's library that provides map projection and datum transformation support. The Projection Engine was first incorporated into ArcSDE 3. It has since been used in MapObjects 2, the ArcView Projection Utility, ArcPad, and ArcGIS 8. The data model is derived from a modified version of the European Petroleum Survey Group's (EPSG) coordinate system model. EPSG publishes a database of coordinate system information plus some very good related documents on map projections and datums. The document provided in this section contains information about the coordinate systems and geographic (datum) transformations supported in ArcGIS. The tables include supported units of measure, spheroids, datums, and prime meridians. The supported map projections and their parameters are listed in one table. The geographic and projected coordinate system areas of interest are available. The geographic transformation tables include the method and parameters as well as the areas of interest. Please browse through this rather long and technical paper and try to find some information on supported coordinate systems and geographic transformations of an area of your interest.

Source: ESRI, 2002. The ESRI Projection Engine: supported coordinate systems and geographic transformations. <http://www.esricanada.com/files/pdf/p_57_projection_engine.pdf> URL last accessed 2004-03-09.