USA, Australia and China are chosen
for case studies, being large countries.
USA
In 1807 President Jefferson established
the ‘Survey of Coast’ that was renamed
in 1836 as ‘US Coast Survey’ and 1878
‘US Coast and Geodetic Survey’. This
organization surveyed the area near the
coast line till 1878. In the meantime
the mapping of interior of county
was done by several organizations
including ‘Army Corps of Topographical
Engineers’. First maps were generally
drawn by hands. Different groups
were working in uncoordinated way.
Therefore US Geological Survey was
established in 1879. USGS started with
topographic survey on various scales
from 1:24,000 to 1:250,000. But the
object of complete coverage could not
be achieved by target year of 1925.
Thereafter the National Topographical
Program was introduced in 1939. This
legislation laid down the specifications
for the National Topographical Map
Series and appropriate standards of map
accuracy. Based on this programme
1:24,000 scale (except deserts), 1:62,500
scale (in Alaska 1:63,360) and 1:250,000
scale surveys were adopted. USGS
began using aerial photographs to
produce and update maps since 1930s.
By 1947 maps at the scale of
1:24,000/1:62,500 covered only 25% of
USA but by 1968 this had been increased
to 78%. In 1976, national coverage
at 1:24,000 was 68% complete and
about 80% of the Alaska (at 1:63,360)
had been covered. By that time many
countries including India had almost
complete coverage on 1:50,000 scale.
In order to speed up the revision of
existing map sheets, an interim revision
was introduced in 1967. Extensive and
important topographical changes were
overprinted in purple on exiting maps by
using aerial photography but without field
check.. In 1975, it was decided that for
all areas not yet covered by traditional
1:24,000 scale sheets, orthophotoquads
(rectified photographs with important
details, names grid/graticule and marginal
items etc) should be produced especially
for deserts and less developed areas.
As it became evident that complete
coverage by traditional maps at 1:24,000
scale could not be achieved before
the end of century, manuscript maps
without cartographic fair drawing
have been printed since 1982.
Based on the Metric Conversion Act of
1975 a modification of official topographic
maps of the USA was made to confirm
to the metric system. In the 1980s, the
use of computer to scan, redraw and
publish the maps significantly reduced
the time required to update maps in
areas of rapid growth. A new series on
1:100,000 scale was published which
was compiled from 1:24,000 scale
maps. Some states adopted 1:25,000
scale after adoption of metric system.
Now the complete country except Alaska
is covered by more than 55,000 sheets
produced on 1:24,000/1:25,000 scale
and Alaska is covered by 2,700 sheets
on 1:50,000 scale. In addition complete
topographic coverage of USA is also
available at 1:100,000 scale and 1:250,000
scale. Most of the data is now available in
digital form. Maps or data can be obtained
by anyone without any restriction.
USGS provides topographical maps,
orthophoto maps and aerial photographs
in the entire USA online for nominal
charges. This data is also available
from various websites e.g. topozone.
There is demand for complete and up
to date topographical information. For
a country of the size of USA , it is huge
task even with the latest technology.
Therefore to meet this requirement, USGS
has started ‘The National Maps Corps
Volunteer Programme’. Any citizen having
a GPS receiver can become the volunteer
for a selected part of the country. He
will provide GPS data and information
about new details. After validating the
information, the USGS staff will update
the topographical database. Now USGS is
expecting that the changes in topographical
data will be captured and integrated with
the existing data in a process of continuous
update, rather than through cyclical
revision of 10 to 20 years. They expect that
currentness of the data will be measured
in months and not in years and decades.
China
China also underestimated the efforts
needed to produce the topographical
maps and in 1903 they originally targeted
to produce a map series at 1:25,000
scale. But this proved impossible due
to the insufficiently advanced state of
available technology and the enormous
geographical extent of the country. In
1914 it was decided to generate mapping
at 1:50,000 and 1:100,000 scale as an
alternative. Preparation of these series
was interrupted due to outbreak of World
War I. Moreover sheets produced prior to
that, were strongly criticized because of
their general inaccuracy. In 1928 a revised
programme was introduced by the newly
created Central Bureau of Land Survey
(CBLS). Triangulations commenced in
1930 and from 1932 photogrammetric
techniques were used for topographical
survey. Tremendous efforts were made
but the progress suffered because of civil
conflicts and the war between China and
Japan. Till then, the scales employed
were 1:25,000, 1:50,000, 1:100,000 and
1:2,50,000. When People’s Republic of
China was established in 1949, a new
survey of China was undertaken because
original base materials were transported
to Taiwan by the previous government.
Approximately 8000 sheets of 1:50,000
series had been produced which covered
about a third of the country. However these
were of somewhat inconsistent quality.
In 1956 a new National Bureau of
Surveying and Mapping (NBSM) was
set up. This employed the Bejing coordinate
system of 1954. The control
work was finished by end of 1978.
The sheetline, numbering methods and
symbolization of topographic maps were
standardized which were similar to former
USSR. Following series were used.
- 1:25,000 For large towns and
industrial zones.
- 1:50,000 For other populated areas
- 1:100,000 For desert and high mountains.
The NBSM expanded & became fully
operational in 1973. It implemented
an extensive revision programme for medium scales. In 1982 three large
Bureaus together with numerous provincial
Bureaus were setup and passed to Ministry
of Urban & Rural Construction and
Environment Protection. At that time about
80,000 personal were involved in various
aspects of mapping. Priority was given to
the large-scale surveys which resulted in
the production of sheets at 1:10,000 and
also photomaps. Even larger scales had
been adopted for major towns in certain
cases. By 1990 approximately 1,65,000
sheets on large scales covering built up
areas had been completed. It also finished
the topographical mapping of the entire
country on 1:50,000/1:100,000 scales.
China has adopted digital technology
since 1990 for converting the maps in
digital form. National Topographical Data
Base on 1:50,000 scale was created in
2005. This task involved 10,000 people
from 100 different organizations. It was
coordinated by NBSM and was completed
in eight years. Besides vector data, this
dataset includes raster maps, imageries
(including 1m resolution imageies for
cities), terrain, landcover and meta-data.
Chinese topographical maps except
general-purpose geographical maps
and tourists maps are generally not
available to general public. The
government is providing geo-spatial
data to the industry on need base.
Australia
In Australia topographic mapping
was undertaken by Commonwealth
and State government mapping
organizations. In 1945 National
Mapping Council was created by
agreement between the Commonwealth
and State governments. Its function
was to co-ordinate Commonwealth
and State mapping activities. In 1966,
metric scales were introduced.
By 1967 the whole of Australia was
covered by aerial photography for the
first time. The medium scale contoured
mapping covered a reasonable area. In
year 1968, 1:250,000 scale planimetric
map series was completed. Relief on
this sereies was generally shown by spot heights and hill shading. However
20% sheets were contoured.
In 1967, compilation of 1:100,000
scale National Topographical Map
Series (NTMS) commenced. Relief was
generally depicted by 20 meter contours.
It was published by Commonwealth
Government with some assistance
provided by the States. There are 3065
sheets in this series. Compilation of this
series was completed by 1988. Initially
the publication programme had been
restricted to 1646 sheets along with the
coastal margins of the continent and
island state of Tasmania. The interior of
the continent was compiled at 1:100,000
scale but published at 2,50,000 scale.
This was completed by 1986.
In 1975 the publication of the 1:2,50,000
scale National Topographic Map
Series commenced. Sheets in this
series depict contours at 50 meters
interval. The 1:2,50,000 scale NTMS
is published to civilian specifications
and a parallel 1:2,50,000 scale Joint
Operations Graphic series is produced
for defence requirements. All of the
541 sheets required at this scale were
completed by 1989 in both the series.
Now topographic maps at scales of
1:50,000 and 1:25,000 are produced by
Commonwealth and State government
mapping organizations. Coverage at
these scales is generally confined to
the closer settled areas and other places
of specific interest. The State mapping
organizations also undertake mapping
at scales of 1:10,000 and larger for
cities and other fast developing areas.
Now Geoscience Australia is responsible
for producing topographic map products
with a national coverage. The NATMAP
product brand refers to Geoscience
Australia’s new 1:100,000 and 1:2,50,000
scale paper map products. The GEODATA
product brand refers to its structured digital
GIS and mapping data product at scales
between 1:2,50,000 and 1:1 million. Now
1:2,50,000 is the largest scale at which
National Digital Topographic Data Base
exists for entire continent. It is available
in different themes and contains a number of feature classes. Large-scale digital
data is available for developed areas.
Most of the digital products are priced
and are licensed for use and available to
users without any further restriction.
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