Back to the basic – by
popular demand
Mapping is
any activity carried out with the intent of collecting credible and accurate
data on an object e.g. Building, roads, human genome
or phenomenon e.g. buying patterns, smuggling and
illegal immigration. To go a step further, spatial mapping is when the
geographical coordinates of the object or phenomenon is also taken. In other
words, the GPS coordinates!!!!
So what
are geographic coordinates ooh!!
Geographic coordinates are the X
and Y of any object position on the face of the earth pronto!! X stands for the
longitude, Y for the Latitude. The X and Y tells us the unique position of an
object on the face of the earth.
How do we
now get the X and Y coordinates when mapping? Namely
on the field and in the laboratory or on the Workstation even your mobile
device!!First
Choice? Lets take field mapping first
We deploy a technology called Global Positioning System
Technology, GPS for short. The technology works through what we know as GPS
Enabled devices. These are common now as almost all telecommunication devices,
cars, trains even wristwatches are now GPS Enabled!!!
How
do we use these devices?
When we use these devices to map a road for example, we use
certain functions that exist in the devices. These functions assist us to get a
real life representation of how the road looks. Really, a road doesn’t look
like a lamp post, neither does it look like a building!!!
Note: not all GPS Enabled devices
have Mapping capability but
all have the ability to register the basic X and Y of a location. Devices
designed with the objective of mapping are usually labelled as so. For example-
Handheld GPS devices, Rugged GPS Enabled Notebooks amongst others.
So what does the GPS technology map? The GPS Enabled devices
map what we call features. Features are of three main kinds- Points, Area and Lines.
Second
Choice: How do we now get the X and Y coordinates when mapping? When one cannot
go out? Mapping can also be an indoor activity lol One cannot map human genome
in the garden anyway!!! Lol
Today, we
are all familiar with dynamic or internet based maps, satellite imagery and
aerial photographs. In a GIS Laboratory or Workstation and with the right tools
for analysis and interpretation, certain X and Y coordinates of recognizable
locations on the earth surface can be extracted. Note that these remotely
sensed datasets must be themselves georeferenced.
Even simpler
is your handy google maps engine. Here by simply clicking geocoded locations on
the face of the earth, their X and Y coordinates can be extracted For example
putting in a search for lagos will generate a marker on the google map engine
that contains the X and Y coordinates of Lagos!!!!!!
Go to presentation page on menu bar and click links on presentations titled 'GPS Data' and 'Coordinates&Projections'for greater details
