How can you find your place in space?
Every home has a special address. In fact, your school, your library, and your doctor's office all have unique addresses. Each of these addresses identifies your "location on Earth" or your "geospatial" home.
"Geo" means "earth." Spatial suggests "location" or an address. By definition then, geospatial refers to addresses of places on Earth.
To locate places on Earth, the first tool that comes to mind is a map or a globe. Maps and globes are simply small models of the Earth. Models can be round (a globe) or flat (a paper map).
Maps are all about location. They help us visualize, or picture places and spaces with the help of a set of imaginary lines.
The Earth is divided into halves, or hemispheres. The hemispheres can be north and south or east and west. The equator is the imaginary line dividing the Northern and Southern Hemispheres. The Eastern and Western Hemispheres are divided by the prime meridian (0°) and, opposite it on the globe, the 180° meridian.
Circling the world, the equator is a latitude line. Latitude is measured in degrees north or south of the equator. The equator has a latitude of 0°. The North Pole's latitude is 90°north, the South Pole's 90° south.
Wrapping around the world from north to south, the prime meridian is a longitude line. Longitude is measured in degrees east or west of the prime meridian. With a value of 0?, the prime meridian passes through Greenwich, England. Longitude lines can be numbered from 0° to 180° east or west.
These lines divide the planet and intersect, giving each location a unique "address."
Geospatial technology takes map reading and map making to a new level. Using geospatial technology, every feature on the Earth's surface is assigned a unique address. These addresses are expressed as coordinates, using latitude and longitude.
Beginning with that unique location, geospatial tools and technology add layers of descriptive information to that spot. Geospatial tools pool data from many sources and display that information in pictures and graphs.
Geospatial tools include the use of :
GPS easily determines the coordinate address of any feature on the Earth's surface. A GPS allows easy navigation from one point to another. Car navigation systems use GPS!
GIS is a computerized map. Using GIS, layers of descriptive information can be meshed for a particular address. GIS often pulls data from many different sources and displays that information in pictures and graphs. GIS can even use imagery of the Earth that has been captured from satellites!
Remote sensing gathers information about the Earth from a distance. Some things are too big for direct study and some places are just too far away. Using satellites and aerial photography, these places can be studied through remote sensing.
Maps help to answer the question, what is there? NASA leads the way using geospatial tools to go further and answer "what else is there", "why is it there", "what is nearby", "what is en route", and "why do I care?"
|
