High Resolution 1:10,000 scale Mapping Strategy of Multi ... - NDMA

3 Scale
4 Resolution
on anticipated uses and on the scale and resolution of the
source data. A volcano, for example, may be represented
as a point at 1:250,000 scales, but it could well be a
polygon at 1:20,000.
Similarly, flood-prone areas may be represented as lines
bordering rivers at scales smaller than 1:50,000, but as
polygons on 1:10,000 scale maps.
Planners must keep in mind that point and line
representations may well be used for depicting variable
locations, but they are seldom used for GIS operations
involving cell measurement.
Regarding scale, planners or GIS users can take
advantage of the flexibility some GIS offer by entering
data at various scales and later requesting the system to
adjust the scale to fit the particular purpose or stage of
planning.
Small to medium scales for resource inventory and project
identification; medium scales for project profiles and pre
feasibility studies;
Large scales for feasibility studies, hazard zone mapping,
and urban hazard mitigation studies.
Resolution or spatial accuracy of the database will be
reflected in the number of cells (columns and rows or Xs
and Ys) making up the database. The greater the number
of cells used to cover a given area, the higher the
App 7