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“India
is locked in wrong and outdated datum” |
Instead
of copying WGS 84, India should explore the opportunity
of being a leader in realizing better geodetic
system, Dr
Muneendra Kumar emphasizes in a tête-à-tête
with Coordinates |
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| What are your views about
New Indian Map Policy? |
To
have two map series is a bold and ambitious approach
to satisfy both the defense and civilian users. But,
based on my experience of working with countries round
the world, I have four observations:
1. Selection and use of datum and mapping system are
linked with future development and thus should not be
“frozen” into any policy. Here, I will point
out an example where a particular datum was “protected”
under a national constitution. This provision created
many roadblocks for the timely development of Geospatial
information of that country. In the present case, Government
of India has been advised to “lock-in” the
wrong and outdated datums, projections, and grid systems.
This would create additional hindrances to jeopardize
improvement(s) in India’s future modernization.
2. Multiple datums, projections, and grid systems in
the two series will create operational problems.
3. Selection and depiction of Geospatial information
in any DSMs should be decided one map at a time. I have
a very educative experience, which I got in 1967 during
my service with Directorate of Military Survey. A feature,
otherwise completely “innocent” had to be
deleted in one map.
4. It would be practically not possible for India to
maintain two map series for its large area. Extent coverage
of DSMs should be only over special areas; this would
be cost saving also. Finally, considering the geodetic
aspect, the most serious problem is that the “Everest/WGS
84” is NOT a valid datum. |
| In your opinion Indian Datum
is inadequate. Please elaborate. |
During my service with NGA, I studied and worked
with over 250 datums of the world and there I came
to know all about the Indian Datum. Not only it is
more than a century old, for today’s accuracy
requirements, it is extremely “weak” in
definition. It has also got distorted. I can elaborate
other geodetic inadequacies and accuracy deficiencies,
but this interview would not be the right place.
Here, I would add a straightforward factual observation:
The 19th century Indian Datum cannot provide “Good
Coordinates”, which are critical to satisfy
the 21st century high accuracy requirements.
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What
about the security issues regarding this? |
The Survey of
India (SOI) has over emphasized the security issue for
use of the 19th century Indian Datum. All the pertinent
details about it are well known like an open book.
I have certain details, which are very important for
protecting India’s national interest. SOI does
not know about them. My offer to share and explain the
intricacies is still on. |
If
Indian datum is to be replaced, then why not WGS 84
or a new one like NAD 83? |
WGS
84 is a global system developed by U.S. Defense Department
for its own requirements. In the absence of any other
“global” geodetic system, IHO in 1983 and
ICAO in 1989 recommended the use of WGS 84 for sea and
air navigation. Other small countries also adopted it
as a matter of convenience. Many large countries and/or
two continents have realized their own geodetic systems.
And, one continent with 50+ countries is still trying
to accomplish the same.
However, in recent years, WGS 84 has been realized with
incorrect definition. Additionally, there have been
new geodetic researches since the 1980ss. Thus, India
should not copy the WGS 84, but now has the opportunity
to be the leader in realizing a better geodetic system.
As for copying the NAD 83, I had explained to Indian
geodesists and also at INCA 2003 that this datum was
established as a special effort to replace the NAD 27.
It was the most practical solution at that time. I would
point out that there was no GPS; otherwise NGS geodesists
might have adopted a different approach. I was very
much involved in the development of both the NAD 83
and WGS 84 and thus know all about their strengths and
limitations.
When India can define and realize a 21st century geodetic
system, more so when it is launching new map series,
there cannot be any geodetic reasons to copy the 1984
geodetic system or 1983 datum. |
What
will be the advantages by realizing a new Indian Geodetic
Reference System? |
The new Indian
Geodetic Reference System, if defined correctly with
the latest fundamental constants and temporal modeling,
and the IAG Resolution No. 16 of 1983, will be the best
possible realization, which others would like to copy.
It will also become the most accurate foundation for
the two map series, nautical and aeronautical charts,
height and ocean depth systems, national cadastre and
urban mapping, and other Geospatial information. |
What
are the “logistics” involved? |
Based on the
experience acquired from the South American project,
I would say that a network of about 20-25 fundamental
GPS stations would be needed. If the need of principal
control stations for airport conversion under ICAO mandate
is still there, during actual design process this GPS
network can be appropriately expanded by another 10-15
stations. Including safety factor, data collection time
at each station will be a maximum of 7 days. Another
important point is that the logistic, size, and time
for the project for new geodetic system is not to be
“tied” to the requirements for dense geodetic
control for India’s other projects.
This project is realizable and affordable, if properly
designed and executed under good management. The South
American SIRGAS 1995 and 2000 projects are good examples.
These projects also show the importance of consultation
and international cooperation. A few neighbors are waiting
for this Indian project. |
| Whether India needs a new
vertical datum of the type like NAVD 88. |
Here, I will
first point a few specific features and geodetic issues
pertaining to NAVD 88. This datum was established as
a practical solution to replace the NGVD 29, which had
become non-usable due to poor “zero”
definition and excessive distortions. Though Canada
participated in the project, it later on did not implement
it due to a possible slope of about three meter from
East to West. The Helmert’s height system is also
geodetically not the best. There are many other zero
definition issues, which have full scope for improvement.
Thus, NAVD 88, which was established 18 years back,
is not the right type to be copied by India.
Since the 1980s there has been new research, which shows
that GPS surveyed ellipsoidal heights can replace the
orthometric heights and thus India does not need a completely
readjusted another BIG vertical datum with orthometric
heights.
However, India should maintain the present datum by
redefining with geoid as the zero reference. |
| Does India need a big spiritleveling
project towards updating the existing datum? |
To maintain the
existing datum, new leveling on a big scale is NOT needed.
But, re-leveling of week sections and of lines, mostly
in areas of crustal movement, should be carried out
to replace the existing lines. This releveling effort,
if carefully planed and executed, would save lot of
time, money, and resources. The updated network is to
be adjusted using weighted constraint technique with
geoid as zero reference. |
For
using ellipsoidal heights, what type of a vertical datum
is needed? |
The 3-D geodetic
system is the “datum”, which defines the
three position coordinates, viz., latitude, longitude,
and ellipsoidal height, of any surveyed point. Here,
the reference ellipsoid, as defined within the 3-D geodetic
system, is then considered as the “zero”
reference for the heights.
This 3-D composite approach thus enables us to replace
the centuries old practice defining two separate datums,
horizontal and vertical, using two separate ellipsoids. |
If
ellipsoidal heights can do the job, why they have not
been used earlier? |
Firstly, the
ellipsoidal heights were not used earlier, because they
were not available. Secondly, when we started getting
them with necessary and sufficient accuracy from GPS
surveying, nobody showed any new enterprise to research
whether they can be used or not.
My two research papers in COORDINATES show that ellipsoidal
heights not only do the jobs, but they do them better,
especially in mountainous and remote areas. The “zero”
definition is globally consistent and there will be
NO conflicts.
For India, the using ellipsoidal heights will have many
advantages. Indian users have just to check and test
them. After this there should not be any “bar”
for not using the new GPS surveyed product.
Here, I would like to point two important issues pertaining
to the use of orthometric heights in India. It needs
(1) gravity “g” observed at close intervals,
and (2) average “g” computed along the plumb
line from the ground to the geoid. First requirement
is extremely costly and practically very difficult for
areas along the Himalayas. The second can never be met.
As India did not participate in the NIMA- NASA project
of 1996, it still does not have a geoid over its territory
with good absolute accuracy. As it now seems that India
might not release its gravity data for a global solution,
I am sure that Indian geodesists are aware of that theoretical
modeling is a very poor option to improve geoid. Furthermore,
India only has normal orthometric heights. This means
that it requires the quasi-geoid and not the geoid.
Thus, considering the above limitations and fact that
India only has normal
heights system, the change over to ellipsoidal heights
should be a very practical and money saving option.
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| Is there any security risk? |
There is no security
risk in using ellipsoidal heights and/or depths. I do
not think that there is anyone who can prove it other
way. |
Why
there should be a new “format” for Indian
maps and charts? |
First, I would
bring out the serious limitations of the currently used
projection mapping. In this centuries old traditional
approach, the distortions are inevitable. In Universal
Transverse Mercator (UTM) projection, which has been
accepted for the first time under India’s new
map policy, a 10 km EW distance could distort enormously
as map coverage moves towards the N- or S-Pole from
the Equator. At 80- degree latitude, the distortion
is about 600%. The associated grid system has “breaks”
at zone boundaries and each zone has its own grid North.
In addition, the most serious disadvantage for military
operations, discontinuity in grid coordinates is inevitable
and occurs frequently at zone junctions within the area
covered by any ellipsoid and also at the junctions between
two adjoining ellipsoids. Incidentally, in many problems
in this global grid system, one major breakdown occurs
pertaining to the area covered under the Everest ellipsoid.
And, India would have to bear it, just for copying the
UTM.
From all this, we had no “escape” before
my research of the KMAP System. In this “no-projection”
system, maps and charts are seamless with practically
zero distortion. They also will have true orientation,
no discontinuity in coordinates, and contours drawn
with ellipsoidal heights. This new approach is the biggest
breakthrough in all making large-scale topographic maps
and nautical and aeronautical charts.
In view of the above “real” advantages,
I would propose to SOI and all other Indian cartographers
to check and test the KMap System for the two new DSMs
and OSMs.They will find it a cartographic miracle. Then,
adopting the KMap System, India would lead the world
in producing the best possible quality DSMs and OSMs. |
If
the “problems” were there, why they have
been and are still in use? |
There was NO
other alternative mapping system(s). Everyone accepted
the projection mapping as the inevitable solution. In
case of the U.S. Military Grid Reference System (MGRS),
which is now) used with UTM, the
problems have kept mounting since its invention in 1949.
But, no consensus and improved solution could be found.
With no other option available, users still have to
use the same system. Starting its new map series, India
has the opportunity to avoid the MGRS, the problematic
grid system, which comes with use of WGS 84 and UTM. |
Why
KMap System? |
The KMap System,
a 21st century cartographic miracle, provides at least
thousands of times better solution compared to any projection(s).
It will produce the best quality DSMs and OSMs, including
all charts. |
What
about using Absolute Gravimeter in India. Any comments. |
The absolute
gravimeter is like a “white elephant”. After
buying and surveying a few absolute gravity stations,
a country hardly has any substantial use for this extremely
costly meter.
However, there are a few friendly countries, which might
help India. This would be the most practical approach
to get the absolute gravity value established in India.
If India has already committed its funds, there is another
alternative to consider building a newly researched
“small” absolute gravity meter. This meter
can replace the relative gravity surveys and has some
potential for selling. |
| Does India need a big gravity
survey campaign? |
Under NASA’s
gravity mission program, two special satellites have
already been successful in collecting gravity data globally.
Third satellite is planned for launching in the near
future and that will provide, if successful,
very dense coverage. All this data will be available
to everyone.
In view of the above, Indian gravity survey plans should
be drawn accordingly. |
| Why India should not be
“copying”? |
Of course, no
one should be “reinventing the wheel”. But,
copying a solution for geodetic system or datum from
USA, UK, Europe, or any other country might not the
best. Instead, with “Good” consultation,
countries should come up with better solutions to specifically
meet or suit their own needs. |
| What are the implications
of your proposal on Indian security? |
I am an independent
scientist with my own innovative research ideas and
concepts and have experience and expertise to generate
“Good” geodetic solutions. I have no ties
and hidden motives and am working as a consultant with
clean slate with no intention of getting involved with
any type of security issues. My proposed solutions are
geodetic and scientific with everything crystal clear. |
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Dr
Muneendra Kumar earned MS, in Mathematics
with three gold medals and PhD, in Geodetic Sciences.
He is Fellow of the International Association
of Geodesy and Marine Technology Society. He served
in Survey of India, Indian Military Survey, US
National Geodetic Survey, and National Geospatial-
Intelligence Agency, from where he retired as
Chief Geodesist. Dr Kumar has occupied the Research
Professor Chair at the |
U.S. Naval University, has been Special Consultant
to 100+ countries, and Geodesy Advisor to UN Food
and Agriculture Organization. He is an authority
on marine positioning and geodesy, and GPS surveying.
He is known as Dr. or Senor "WGS84".
Dr Kumar has numerous presentations, publications,
special geodetic and GPS seminars, and workshops
to his credit. His pioneering and innovative concepts
and researches include Projection and Distortion
Free and Seamless Kumar Mapping (KMap) System,
GPS Surveyed Time-Invariant Seafloor Depths, and
use of ellipsoidal heights in place of orthometric.
The list of projects where he has been consulted
is too long. We can put them in five broad categories
(1) 55+ countries “ADOS” project for
IAG, “AFRICOVER” for UN Food Agriculture
Organization, and “AFREF” for IAG
Commission for Africa; (2) 25+ countries “SIRGAS”
for IAG and PAIGH;
(3) 12+ countries “WHS” for the East
European countries; (4) 100+ projects for countries,
individually and/or in groups, around the world
to update and modernize their geodetic infra-structure,
mapping, and height systems; (5) IHO’s adoption
of WGS 84 for nautical charts and ICAO’s
conversion of Airports.
He is probably the only person who has all the
pertinent detailed information about the Indian
datum and its various updates used by neighboring
countries and also a very critical issues for
DSMs. He is also the only expert who participated
in the development, defining, and realization
of the WGS 84, NAD 83, SIRGAS, NAVD 88, KGS 95,
PRS 92, and geodetic systems, vertical datums,
and mapping projects of many countries. He is
a Guru of marine positioning and boundaries and
knows all about the geodetic aspects for the Law
of the Sea. He has also researched the best mapping
system, survey technique for ocean bottom, and
use of ellipsoidal heights. He has the unique
combination of highest level of theoretical knowledge
and expertise in geodetic systems and mapping
with worldwide practical experience. |
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| August
2006 |
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