MAP PROJECTIONS - Exploration of Google Earth Gmat 2700 Geometry of Coordinate Reference Systems

Exploration of Google Earth (GMAT 2700) Donny Darmawan Introduction to Google Earth Google Earth is a geographic information program that have been put together by Google inc. to give the public a greater exploration of the world. Google Earth combines satellite imagery, maps and the power of Google search (database system) to put the world’s geographic information into a simple easy to use program. Updated and pre- paid Google Earth also involve GPS as one of their input and allow csv. Files to be inserted into the geographic information system.

Exploration of Google Earth (GMAT 2700) Donny Darmawan Relating Google Earth and Map projection Map projection is basically: (picture taken from

Exploration of Google Earth (GMAT 2700) Donny Darmawan Relating Google Earth and Map projection When building whole-earth databases, a single global projection is the most convenient to use. Google Earth uses Simple Cylindrical projection for its imagery base because this is a simple map projection where the meridians and parallels are equidistance, straight lines, with the two sets crossing at right angles. Google Earth uses Simple Cylindrical projection for its imagery base because this is a simple map projection where the meridians and parallels are equidistance, straight lines, with the two sets crossing at right angles. This projection is also known as WGS84 which is identical to MGA94

Exploration of Google Earth (GMAT 2700) Donny Darmawan Simple Cylindrical Projection The aim of the simple cylindrical projection is to minimise the distortion of the curved earth to make a better approximation, if not accurate, of the Google Earth image. The projection used in Google Earth is The Universal Transverse Mercator (UTM) projection

Exploration of Google Earth (GMAT 2700) Donny Darmawan UTM Projection This projection is based on a cylinder and the tangent of that cylinder is the meridian of longitude. The UTM divides the world into zones. These 6º zones are useful to eliminate distortions. The scale factor is therefore which is close to 1, the true value of northing and easting

Exploration of Google Earth (GMAT 2700) Donny Darmawan Using Google Earth Google Earth is very user friendly because it provide with many different function in a click of a mouse. Google Earth is very user friendly because it provide with many different function in a click of a mouse. These functions include: zooming, rotating, tilting, moving around, locating grid north. These functions include: zooming, rotating, tilting, moving around, locating grid north.

Exploration of Google Earth (GMAT 2700) Donny Darmawan Functions of Google Earth Define accurate latitude and longitude. Define accurate latitude and longitude. Define building terrain like 3D objects and other layers such as population. Define building terrain like 3D objects and other layers such as population. Locate and save places. Locate and save places.

Exploration of Google Earth (GMAT 2700) Donny Darmawan Other useful function of Google Earth (extra) World Cup Stadium for Germany 2006 World Cup Stadium for Germany 2006 Flu outbreaks and important information Flu outbreaks and important information Interesting sites such as wonders of the world and strip clubs Interesting sites such as wonders of the world and strip clubs Traffic control Traffic control Weather forecast Weather forecast Driving navigation Driving navigation etc etc

Exploration of Google Earth (GMAT 2700) Donny Darmawan Useful Example of Google Earth The Indonesian volcano in Mount Merapi is expected to erupt slowly. Google Earth helps in identifying the extend of the volcano if it is to erupt and give warnings for people’s evacuation.

Exploration of Google Earth (GMAT 2700) Donny Darmawan Conclusion Because of Google Earth, many people have become aware at the importance of Geographic Information System (GIS) and learn to appreciate map projections. Suddenly, it is easy to

Exploration of Google Earth (GMAT 2700) Donny Darmawan References Rechardus.P, 1972, “Map Projections”, North-Holland Pusblishing Company, London Rechardus.P, 1972, “Map Projections”, North-Holland Pusblishing Company, London Iliffe.J.C, 2000, “datums and map projections”,Whittle Publishing, UK Iliffe.J.C, 2000, “datums and map projections”,Whittle Publishing, UK /GoogleEarth.htm /GoogleEarth.htm /GoogleEarth.htm /GoogleEarth.htm t/notes/mapproj/gif/cylinder.gif t/notes/mapproj/gif/cylinder.gif t/notes/mapproj/gif/cylinder.gif t/notes/mapproj/gif/cylinder.gif