GEOG 222.3 Midterm: GEOG reveiw
by Dayle Meyers
Course CodeGEOG 222.3
This preview shows half of the first page. to view the full 2 pages of the document.
Midterm review !
Lecture 1 - 6, 50 multiple choice !
Geometric - the integration of data, measurement, storage, no analysis!
GIS - computer based data storage, you need to have software, hardware, geo data (spatially
Spatial data - !
Earth based or spatial based !
-Latitude is parallels, start from 0 at the equator and go to the northern or southern
hemisphere (90). Parallel to one another they never cross !
-Longitude is meridians. Prime meridian is only at one location, they go east and west, 180
degrees. They are not parallel to one another they all converge !
-Degree, minute, second or unit is in degrees !
-1 degree = 111km !
The shortest distance on earth always goes through the greater circle, all meridians are great
The seasons are caused by the tilt and revolution of the earth !
-Each hour 15 degrees have passed !
-The rotation causes the equator bulge, this is why the equator is bigger then the poles!
Datum - the reference point or surface which measurements are made !
Geoid - hypothetical surface of the earth !
What is the datum that google earth uses - WS84 !
Projection - to convert or project the 3 dimensional earth to the ﬂat map !
3 major types of projection: or you can do it mathematically !
you will distort the features no matter what projection you use, no projection can preserve all
the object correctly !
UTM - cylindrical projection, each zone is 6 degrees starting from 180 degrees west, every
degrees you move is 6 degrees !
central meridian - is to deﬁne where the central line is for each UTM zone !
#- unit is meter !
Reprojection - if you have the same projection but datum diﬀerent you have to do the
#- location: accurately assigned to the same places on the projection!
#- control point: same location to both properties with the accurate coordinates, you
have to link them together. Control points have to be easy to identify !
1st order - 3 points!
2nd order - 6 points !
3rd order - 10 points!
You're Reading a Preview
Unlock to view full version